Table of Contents
- Package Contents
- Chapter 1 About This Guide
- Chapter 2 Introduction
- Chapter 3 Login to the Switch
- Chapter 4 System
- Chapter 5 Stack
- Chapter 6 Switching
- Chapter 7 VLAN
- Chapter 8 Spanning Tree
- Chapter 9 Multicast
- Chapter 10 Routing
- Chapter 11 Multicast Routing
- Chapter 12 QoS
- Chapter 13 ACL
- Chapter 14 Network Security
- Chapter 15 SNMP
- Chapter 16 LLDP
- Chapter 17 Maintenance
- Appendix A: Glossary
TP-Link T3700G-28TQ User Manual
Displayed below is the user manual for T3700G-28TQ by TP-Link which is a product in the Network Switches category. This manual has pages.
User Guide
T3700G-28TQ/ T3700G-52TQ
1910012358 REV3.0.0
November 2018
CONTENTS
Package Contents ..................................................................................................................................... 1
Chapter 1 About This Guide ....................................................................... 2
1.1 Intended Readers .......................................................................................................... 2
1.2 Conventions .................................................................................................................. 2
1.3 Overview of This Guide.................................................................................................. 3
Chapter 2 Introduction ............................................................................. 8
2.1 Overview of the Switch .................................................................................................. 8
2.2 Appearance Description ............................................................................................... 8
2.2.1 Front Panel .......................................................................................................... 8
2.2.2 Rear Panel ......................................................................................................... 10
Chapter 3 Login to the Switch ................................................................... 12
3.1 Login ............................................................................................................................ 12
3.2 Configuration ............................................................................................................... 12
Chapter 4 System .............................................................................................................................. 14
4.1 System Info .................................................................................................................. 14
4.1.1 System Summary ............................................................................................. 14
4.1.2 Device Description ........................................................................................... 16
4.1.3 System Time ..................................................................................................... 17
4.1.4 Daylight Saving Time ........................................................................................ 18
4.1.5 System IPv6 ...................................................................................................... 19
4.1.6 Management Port IPv4 ..................................................................................... 22
4.1.7 Management Port IPv6 ..................................................................................... 23
4.2 User Management ....................................................................................................... 25
4.2.1 User Table ......................................................................................................... 25
4.2.2 User Config ....................................................................................................... 25
4.3 System Tools ............................................................................................................... 26
4.3.1 Boot Config ....................................................................................................... 27
4.3.2 Config Restore .................................................................................................. 28
4.3.3 Config Backup .................................................................................................. 28
4.3.4 Firmware Upgrade ............................................................................................ 29
4.3.5 System Reboot ................................................................................................. 29
4.3.6 System Reset .................................................................................................... 30
II
4.4 Access Security ........................................................................................................... 30
4.4.1 Access Control ................................................................................................. 30
4.4.2 HTTP Config ...................................................................................................... 31
4.4.3 HTTPS Config ................................................................................................... 32
4.4.4 SSH Config ........................................................................................................ 35
4.4.5 Telnet Config .................................................................................................... 39
4.5 SDM Template ............................................................................................................. 39
4.5.1 SDM Template Config ...................................................................................... 39
Chapter 5 Stack.................................................................................................................................. 41
5.1 Stack Management ..................................................................................................... 47
5.1.1 Stack Info .......................................................................................................... 48
5.1.2 Stack Config ..................................................................................................... 49
5.1.3 Auto Copy Software ......................................................................................... 51
5.2 Application Example for Stack .................................................................................... 52
Chapter 6 Switching .......................................................................................................................... 53
6.1 Port ............................................................................................................................... 53
6.1.1 Port Config ........................................................................................................ 53
6.1.2 Port Mirror ......................................................................................................... 54
6.1.3 Port Security ..................................................................................................... 57
6.1.4 Protected Ports ................................................................................................ 58
6.1.5 Loopback Detection ......................................................................................... 59
6.1.6 Default Settings ................................................................................................ 62
6.2 LAG............................................................................................................................... 62
6.2.1 LAG Table .......................................................................................................... 63
6.2.2 Static LAG ......................................................................................................... 65
6.2.3 LACP Config ..................................................................................................... 66
6.2.4 Default Settings ................................................................................................ 68
6.3 Traffic Monitor ............................................................................................................. 68
6.3.1 Traffic Summary ............................................................................................... 68
6.3.2 Traffic Statistics ................................................................................................ 69
6.4 MAC Address ............................................................................................................... 71
6.4.1 Address Table ................................................................................................... 72
6.4.2 Static Address .................................................................................................. 74
III
6.4.3 Dynamic Address ............................................................................................. 76
6.4.4 Filtering Address .............................................................................................. 77
Chapter 7 VLAN .................................................................................................................................. 79
7.1 802.1Q VLAN ............................................................................................................... 80
7.1.1 VLAN Config ..................................................................................................... 82
7.1.2 Port Config ........................................................................................................ 84
7.2 Application Example for 802.1Q VLAN ....................................................................... 86
7.3 MAC VLAN ................................................................................................................... 87
7.4 Application Example for MAC VLAN ........................................................................... 88
7.5 Protocol VLAN ............................................................................................................. 90
7.5.1 Protocol Group Table ....................................................................................... 91
7.5.2 Protocol Group ................................................................................................. 91
7.5.3 Protocol Template ............................................................................................ 92
7.6 Application Example for Protocol VLAN ..................................................................... 93
7.7 VLAN VPN .................................................................................................................... 94
7.7.1 VLAN-VPN Config ............................................................................................. 95
7.7.2 Default Settings ................................................................................................ 96
7.8 GVRP ............................................................................................................................ 96
7.8.1 GVRP Config ..................................................................................................... 98
7.8.2 Default Settings ................................................................................................ 99
7.9 Private VLAN ................................................................................................................ 99
7.9.1 PVLAN Config ................................................................................................. 101
7.9.2 Port Config ...................................................................................................... 102
7.10 Application Example for Private VLAN...................................................................... 103
Chapter 8 Spanning Tree ....................................................................... 106
8.1 STP Config .................................................................................................................. 112
8.1.1 STP Config ...................................................................................................... 112
8.1.2 STP Summary ................................................................................................. 114
8.2 Port Config .................................................................................................................. 114
8.3 MSTP Instance ............................................................................................................ 117
8.3.1 Region Config ................................................................................................. 118
8.3.2 Instance Config............................................................................................... 118
8.3.3 Instance Port Config ....................................................................................... 119
8.4 STP Security .............................................................................................................. 122
IV
8.4.1 Port Protect .................................................................................................... 122
8.5 Application Example for MSTP Function .................................................................. 125
Chapter 9 Multicast ........................................................................................................................
130
9.1 IGMP Snooping .......................................................................................................... 132
9.1.1 Snooping Config ............................................................................................. 134
9.1.2 Port Config ...................................................................................................... 135
9.1.3 VLAN Config ................................................................................................... 136
9.1.4 Querier Config ................................................................................................ 138
9.1.5 Profile Config .................................................................................................. 140
9.2 MLD Snooping ........................................................................................................... 142
9.2.1 Snooping Config ............................................................................................ 143
9.2.2 Port Config ..................................................................................................... 145
9.2.3 VLAN Config ................................................................................................... 146
9.2.4 Querier Config ................................................................................................ 147
9.2.5 Profile Config .................................................................................................. 149
9.3 MVR ............................................................................................................................ 151
9.3.1 MVR Config ..................................................................................................... 151
9.3.2 Port Config ...................................................................................................... 152
9.3.3 Member Config ............................................................................................... 154
9.3.4 Traffic .............................................................................................................. 155
9.4 Multicast Table .......................................................................................................... 156
9.4.1 Summary ......................................................................................................... 156
9.4.2 Static Config ................................................................................................... 157
9.4.3 IGMP Snooping ............................................................................................... 159
9.4.4 MLD Snooping ................................................................................................ 159
9.4.5 SSM Groups .................................................................................................... 160
9.4.6 SSM Entries .................................................................................................... 161
9.4.7 SSM Status ..................................................................................................... 162
Chapter 10 Routing ............................................................................... 164
10.1 Interface ..................................................................................................................... 164
10.2 Routing Table ............................................................................................................. 167
10.3 Static Routing ............................................................................................................ 168
10.3.1 Static Routing ................................................................................................. 168
10.3.2 Application Example for Static Routing ......................................................... 169
V
10.4 DHCP Server .............................................................................................................. 170
10.4.1 DHCP Server ................................................................................................... 176
10.4.2 Pool Setting .................................................................................................... 178
10.4.3 DHCP Options Set .......................................................................................... 180
10.4.4 Binding Table .................................................................................................. 181
10.4.5 Packet Statistics ............................................................................................. 182
10.4.6 Application Example for DHCP Server and Relay .......................................... 183
10.5 DHCP Relay ................................................................................................................ 185
10.5.1 Global Config .................................................................................................. 187
10.5.2 DHCP Server ................................................................................................... 189
10.6 Proxy ARP .................................................................................................................. 190
10.6.1 Proxy ARP ....................................................................................................... 190
10.6.2 Local Proxy ARP ............................................................................................. 191
10.6.3 Application Example for Proxy ARP ............................................................... 192
10.7 ARP ............................................................................................................................. 192
10.7.1 ARP Table ........................................................................................................ 192
10.7.2 Static ARP ....................................................................................................... 193
10.8 RIP .............................................................................................................................. 194
10.8.1 Basic Config .................................................................................................... 198
10.8.2 Interface Config .............................................................................................. 200
10.8.3 Application Example for RIP ........................................................................... 201
10.9 OSPF .......................................................................................................................... 202
10.9.1 Process ........................................................................................................... 220
10.9.2 Basic ................................................................................................................ 221
10.9.3 Network ........................................................................................................... 223
10.9.4 Interface .......................................................................................................... 224
10.9.5 Area ................................................................................................................. 229
10.9.6 Area Aggregation ........................................................................................... 231
10.9.7 Virtual Link ...................................................................................................... 232
10.9.8 Route Redistribution ....................................................................................... 234
10.9.9 Neighbor Table ............................................................................................... 235
10.9.10 Link State Database ....................................................................................... 237
10.9.11 Application Example for OSPF ....................................................................... 238
10.10 VRRP .......................................................................................................................... 239
VI
10.10.1 Basic Config .................................................................................................... 243
10.10.2 Advanced Config ............................................................................................ 246
10.10.3 Virtual IP Config .............................................................................................. 247
10.10.4 Track Config ................................................................................................... 249
10.10.5 Virtual Router Statistics .................................................................................. 250
10.10.6 Application Example for VRRP ....................................................................... 252
Chapter 11 Multicast Routing ................................................................... 254
11.1 Global Config ............................................................................................................. 255
11.1.1 Global Config .................................................................................................. 255
11.1.2 Mroute Table ................................................................................................... 256
11.2 IGMP ........................................................................................................................... 257
11.2.1 Global Config .................................................................................................. 261
11.2.2 Interface Config .............................................................................................. 262
11.2.3 Interface State ................................................................................................ 263
11.2.4 Multicast Group Table .................................................................................... 264
11.2.5 Application Example for IGMP ........................................................................ 265
11.3 PIM DM ....................................................................................................................... 267
11.3.1 PIM DM Interface ............................................................................................ 272
11.3.2 PIM DM Neighbor ............................................................................................ 272
11.3.3 Application Example for PIM DM .................................................................... 274
11.4 PIM SM ....................................................................................................................... 275
11.4.1 PIM SM Interface ............................................................................................ 281
11.4.2 PIM SM Neighbor ............................................................................................ 282
11.4.3 BSR .................................................................................................................. 282
11.4.4 RP .................................................................................................................... 284
11.4.5 RP Mapping ..................................................................................................... 286
11.4.6 RP Info ............................................................................................................. 286
11.4.7 PIM SSM .......................................................................................................... 287
11.4.8 Packet Statistics ............................................................................................. 288
11.4.9 Application Example for PIM SM .................................................................... 289
11.5 Static Mroute ............................................................................................................. 291
11.5.1 Static Mroute Config ...................................................................................... 292
11.5.2 Application Example for Static Mroute .......................................................... 293
Chapter 12 QoS .................................................................................................................................
296
VII
12.1 Class of Service ......................................................................................................... 299
12.1.1 Trust Mode ...................................................................................................... 299
12.1.2 Port Priority ..................................................................................................... 299
12.1.3 802.1P/CoS to Queue Mapping ..................................................................... 301
12.1.4 DSCP to Queue Mapping................................................................................ 302
12.1.5 Schedule Mode ............................................................................................... 304
12.2 DiffServ ...................................................................................................................... 305
12.2.1 Global .............................................................................................................. 305
12.2.2 Class Summary ............................................................................................... 307
12.2.3 Class Config .................................................................................................... 308
12.2.4 Policy Summary .............................................................................................. 310
12.2.5 Policy Config ................................................................................................... 311
12.2.6 Service Config ................................................................................................ 313
12.3 Bandwidth Control ..................................................................................................... 314
12.3.1 Rate Limit ........................................................................................................ 314
12.3.2 Storm Control ................................................................................................. 315
12.4 Voice VLAN ................................................................................................................ 316
12.4.1 Global Config .................................................................................................. 317
12.4.2 Port Config ...................................................................................................... 318
12.4.3 OUI Config ....................................................................................................... 318
12.5 Auto VoIP ................................................................................................................... 319
12.5.1 Auto VoIP Config ............................................................................................ 319
Chapter 13 ACL ................................................................................... 322
13.1 Time-Range ............................................................................................................... 322
13.1.1 Time-Range Summary .................................................................................... 322
13.2 ACL Config ................................................................................................................. 324
13.2.1 ACL Summary ................................................................................................. 324
13.2.2 ACL Create...................................................................................................... 325
13.2.3 MAC ACL ......................................................................................................... 325
13.2.4 Standard-IP ACL ............................................................................................. 327
13.2.5 Extend-IP ACL ................................................................................................. 328
13.3 ACL Binding ............................................................................................................... 330
13.3.1 Binding Table .................................................................................................. 331
13.3.2 Port Binding .................................................................................................... 332
VIII
13.3.3 VLAN Binding .................................................................................................. 333
Chapter 14 Network Security ................................................................... 335
14.1 IP-MAC Binding .......................................................................................................... 335
14.1.1 Binding Table .................................................................................................. 335
14.1.2 Manual Binding................................................................................................ 336
14.2 DHCP Snooping ......................................................................................................... 337
14.2.1 Global Config .................................................................................................. 341
14.2.2 Port Config ...................................................................................................... 342
14.3 ARP Inspection .......................................................................................................... 343
14.3.1 ARP Detect ...................................................................................................... 346
14.3.2 ARP Defend ..................................................................................................... 348
14.3.3 ARP Statistics ................................................................................................. 349
14.4 IP Source Guard ......................................................................................................... 349
14.5 DoS Defend ............................................................................................................... 351
14.5.1 DoS Defend ..................................................................................................... 352
14.6 802.1X ........................................................................................................................ 352
14.6.1 Global Config .................................................................................................. 357
14.6.2 Port Config ...................................................................................................... 357
14.7 AAA ............................................................................................................................ 359
14.7.1 RADIUS Server Config .................................................................................... 360
14.7.2 TACACS+ Server Config ................................................................................ 361
14.7.3 Authentication Method List Config ................................................................ 362
14.7.4 Application Authentication List Config .......................................................... 363
14.7.5 802.1X Authentication Server Config ............................................................ 364
14.7.6 Default Settings .............................................................................................. 365
Chapter 15 SNMP ................................................................................. 366
15.1 SNMP Config ............................................................................................................. 368
15.1.1 Global Config .................................................................................................. 368
15.1.2 SNMP View ...................................................................................................... 369
15.1.3 SNMP Group ................................................................................................... 370
15.1.4 SNMP User ...................................................................................................... 372
15.1.5 SNMP Community .......................................................................................... 373
15.2 Notification ................................................................................................................ 376
15.2.1 Notification Config .......................................................................................... 376
IX
15.2.2 Traps Config ................................................................................................... 379
15.3 RMON ......................................................................................................................... 381
15.3.1 History ............................................................................................................. 382
15.3.2 Event ............................................................................................................... 383
15.3.3 Alarm ............................................................................................................... 384
Chapter 16 LLDP .................................................................................. 386
16.1 Basic Config ............................................................................................................... 389
16.1.1 Global Config .................................................................................................. 389
16.1.2 Port Config ...................................................................................................... 390
16.2 Device Info ................................................................................................................. 392
16.2.1 Local Info ........................................................................................................ 392
16.2.2 Neighbor Info .................................................................................................. 393
16.3 Device Statistics ........................................................................................................ 394
16.4 LLDP-MED ................................................................................................................. 396
16.4.1 Global Config .................................................................................................. 397
16.4.2 Port Config ...................................................................................................... 398
16.4.3 Local Info ........................................................................................................ 399
16.4.4 Neighbor Info .................................................................................................. 401
Chapter 17 Maintenance ......................................................................... 402
17.1 System Monitor ......................................................................................................... 402
17.1.1 CPU Monitor .................................................................................................... 402
17.1.2 Memory Monitor ............................................................................................. 403
17.2 Log ............................................................................................................................. 403
17.2.1 Log Table ........................................................................................................ 404
17.2.2 Local Log ........................................................................................................ 405
17.2.3 Remote Log .................................................................................................... 406
17.2.4 Backup Log ..................................................................................................... 407
17.3 Device Diagnose........................................................................................................ 408
17.3.1 Cable Test ....................................................................................................... 408
17.4 Network Diagnose ..................................................................................................... 409
17.4.1 Ping ................................................................................................................. 409
17.4.2 Tracert............................................................................................................. 410
Appendix A: Glossary .............................................................................. 412
X
XI
Package Contents
The following items should be found in your box:
One switch
One Power Cord
One Console Cable
One USB Cable
One Power Supply Module Slot Cover
Two mounting brackets and other fittings
Installation Guide
Resource CD for the switch, including:
• This User Guide
• The Command Line Interface Guide
• SNMP MIBs
• 802.1X Client Software and its User Guide
• Other Helpful Information
Note:
Make sure that the package contains the above items. If any of the listed items are damaged or
missing, please contact your distributor.
1
Chapter 1 About This Guide
This User Guide contains information for setup and management of T3700G-28TQ/
T3700G-52TQ switch. Please read this guide carefully before operation.
1.1 Intended Readers
This Guide is intended for network managers familiar with IT concepts and network
terminologies.
1.2 Conventions
When using this guide, please notice that features of the switch may vary slightly depending on
the model and software version you have, and on your location, language, and Internet service
provider. All screenshots, images, parameters and descriptions documented in this guide are
used for demonstration only.
The information in this document is subject to change without notice. Every effort has been
made in the preparation of this document to ensure accuracy of the contents, but all
statements, information, and recommendations in this document do not constitute the
warranty of any kind, express or implied. Users must take full responsibility for their application
of any products.
In this Guide the following conventions are used:
The switch mentioned in this Guide stands for T3700G-28TQ/T3700G-52TQ JetStream
Gigabit Stackable L3 Managed Switch without any explanation.
Menu Name→Submenu Name→Tab page indicates the menu structure. System→System
Info→System Summary means the System Summary page under the System Info menu
option that is located under the System menu.
Bold font indicates a button, a toolbar icon, menu or menu item.
Symbols in this Guide：
Symbol
Description
Note:
Ignoring this type of note might result in a malfunction or damage to the
device.
Tips:
This format indicates important information that helps you make better use
of your device.
More Info:
The latest software, management app and utility can be found at Download Center at
http://www.tp-link.com/support.
2
The Installation Guide (IG) can be found where you find this guide or inside the package of
the switch.
Specifications can be found on the product page at
http://www.tp-link.com.
A Technical Support Forum is provided for you to discuss our products at
https://community.tp-link.com/en/business/
.
Our Technical Support contact information can be found at the Contact Technical Support
page at
http://www.tp-link.com/support
.
1.3 Overview of This Guide
Chapter
Introduction
Chapter 1 About This Guide
Introduces the guide structure and conventions.
Chapter 2 Introduction Introduces the features, application and appearance of the
switch.
Chapter 3 Login to the Switch
Introduces how to log on to the Web management page.
Chapter 4 System
This module is used to configure system properties of the
switch. Here mainly introduces:
System Info: Configure the description, system time and
network parameters of the switch.
User Management
: Configure the user name and password
for users to manage the switch with a certain access level.
System Tools: Manage the configuration file of the switch.
Access Security: Provide different security measures for the
user to enhance the configuration management security.
SDM Template: Manage the hardware TCAM resources.
Chapter 5 Stack This module is used to configure the stack properties of the
switch. Here mainly introduces:
Stack Info: View the detailed information of the stack.
Stack Config: Configure the current stack.
Auto Copy Software: Configure
the Auto Copy Software
function.
Chapter 6 Switching This module is used to configure basic functions of the switch.
Here mainly introduces:
Port: Configure the basic features for the port.
LAG: Configure Link Aggregation Group. LAG is to combine a
number of ports together to make a single high-bandwidth
data path.
Traffic Monitor: Monitor the traffic of each port.
MAC Address: Configure the address table of the switch.
3
Chapter
Introduction
Chapter 7 VLAN
This module is used to configure VLANs to control broadcast in
LANs. Here mainly introduces:
802.1Q VLAN: Configure port-based VLAN.
MAC VLAN: Configure MAC-based VLAN without changing
the 802.1Q VLAN configuration.
Protocol VLAN: Create VLANs in application layer to make
some special data transmitted in the specified VLAN.
VLAN VPN: VLAN VPN allows the packets with VLAN tags of
private netw
orks to be encapsulated with VLAN tags of
public networks at the network access terminal of the
Internet Service Provider.
GVRP: GVRP
allows the switch to automatically add or
remove the VLANs via the dynamic VLAN registration
information and propagate the
local VLAN registration
information to other switches, without having to individually
configure each VLAN.
Private VLAN:
Designed to save VLAN resources of uplink
devices and decrease broadcast. Private VLAN mainly used
in campus or enterprise networks to achieve user layer-2-
separation and to save VLAN resources of uplink devices.
Chapter 8 Spanning Tree This module is used to configure spanning tree function of the
switch. Here mainly introduces:
STP Config: Configur
e and view the global settings of
spanning tree function.
Port Config: Configure CIST parameters of ports.
MSTP Instance: Configure MSTP instances.
STP Security: Configure protection function to prevent
devices from any malicious attack against STP features.
Chapter 9 Multicast
This module is used to configure multicast function of the
switch. Here mainly introduces:
IGMP Snooping: Configure global parameters of IGMP
Snooping function, port properties, VLAN and multicast
VLAN.
MLD Snooping: Configure global parameters of MLD
Snooping function, port properties, VLAN and multicast
VLAN.
MVR:
Configure the Multicast VLAN Registration (MVR)
feature.
Multicast Table: View different types of multicast table.
4
Chapter
Introduction
Chapter 10 Routing The module is used to configure several IPv4 unicast routing
protocols. Here mainly introduces:
Interface:
Configure and view different types of interfaces:
VLAN, loopback and routed port.
Routing table: Displays the routing information summary.
Static Routing: Configure and view static routes.
DHCP Server: Configure the DHCP feature
to assign IP
parameters to specified devices.
DHCP Relay: Configure the DHCP relay feature.
Proxy ARP: Configure the Proxy ARP feature to enable hosts
on the same network but isolated at layer 2 to communicate
with each other.
ARP: Displays the ARP information.
RIP: Configure the RIP feature.
RIP is an interior gateway
protocol using UDP data packets to exchange routing
information.
OSPF: Configure the Open Shortest Path protocol.
VRRP: Configure the Virtual Router Redundant Protocol.
Chapter 11 Multicast Routing This module is used to configure several
multicast routing
protocols for multicast data forwarding. Here mainly introduces:
Global Config:
IGMP: Configure the IGMP features.
PIM DM: Configure the PIM DM features.
PIM SM: Configure the PIM SM features.
Static Mroute: Configure the static multicast routing
features.
Chapter 12 QoS
This module is used to configure QoS function to provide
different quality of service for various network applications and
requirements. Here mainly introduces:
Class of Service: Configure
priorities, port priority, 802.1P
priority and DSCP priority.
DiffServ: Configure classes, policies and services to allow
traffic to be classified into streams and given certain QoS
treatment.
Bandwidth Control: Configure rate limit feature to control the
traffic rate on each port; configure storm control feature to
filter broadcast, multicast and UL frame in the network.
Voice VLAN: Configure voice VLAN to transmit voice data
stream within the specified VLAN.
Auto VoIP: Configure the Auto VoIP feature to prioritize the
transmission of voice traffic.
5
Chapter
Introduction
Chapter 13 ACL
This module is used to configure match rules and process
policies of packets to filter packets in order to control the
access of the illegal users to the network. Here mainly
introduces:
Time-Range: Configure the effective time for ACL rules.
ACL Config: Configure the ACL rules.
ACL Binding: Bind the ACL
to a port/VLAN to take its effect
on a specific port/VLAN.
Chapter 14 Network Security This module is used to configure the multiple protection
measures for the network security. Here mainly introduces:
IP-MAC Binding: Bind the IP address, MAC address, VLAN ID
and the connected Port number of the Host together.
DHCP Snooping: DHCP Snooping functions to monitor the
process of the Host obtaining the IP address from DHCP
server, and record the IP address, MAC address, VLAN and
the connected Port number of the Host for automatic
binding.
ARP Inspection: Configure ARP inspection feature to prevent
the network from ARP attacks.
IP Source Guard: Configure IP source guard feature to filter
IP packets in the LAN.
DoS Defend: Configure DoS defend feature to prevent DoS
attack.
802.1X: Configure common access control mechanism for
LAN ports to solve mainly authentication and security
problems.
AAA: Configure
the authentication, authorization and
accounting features.
Chapter 15 SNMP This module is used to configure SNMP function to provide a
management frame to monitor and maintain the network
devices. Here mainly introduces:
SNMP Config: Configure global settings of SNMP function.
Notification: Configure notification function for the
management station to monitor and process the events.
RMON: Configure RMON function to monitor network more
efficiently.
Chapter 16 LLDP
This module is used to configure LLDP function to provide
information for SNMP applications to simplify troubleshooting.
Here mainly introduces:
Basic Config: Configure the LLDP parameters of the device.
Device Info: View the LLDP information of the local device
and its neighbors.
Device Statistics: View the LLDP statistics of the local device
6
Chapter
Introduction
Chapter 17 Maintenance
This module is used to assemble the commonly used system
tools to manage the switch. Here mainly introduces:
System Monitor: Monitor the memory and CPU of the switch.
Log: View and configure the system log function.
Device Diagnose: Including Cable Test and Loopback. Cable
Test tests the connection status of the cable connected to
the switch; and Loopback tests if the port of the switch and
the connected device are available.
Network Diagnose: Test if the destination is reachable and
the account of router hops from the switch to the
destination.
Appendix A Glossary
Lists the glossary used in this manual.
Return to CONTENTS
7
Chapter 2 Introduction
2.1 Overview of the Switch
T3700G-28TQ/T3700G-52TQ is an L3 managed switch that features advanced L3 routing,
10Gbps wire-speed, physical stacking and removable power supply module and fan module,
designed to meet the needs of convergence layer. T3700G-28TQ/T3700G-52TQ is ideal for
large businesses, campuses or SMB networks requiring an outstanding, reliable and affordable
10 Gigabit solution.
T3700G-28TQ/T3700G-52TQ supports stacking of up to 8 units, thus providing flexible
scalability and protective redundancy for your networks. Moreover, aiming to better protect
your network, T3700G-28TQ/T3700G-52TQ supports 2 power supply modules.
T3700G-28TQ/T3700G-52TQ can fully implement resilient scalable networks due to its
advanced features such as OSPF, VRRP, IGMP and PIM DM/SM.
2.2 Appearance Description
2.2.1 Front Panel
The front panel of T3700G-28TQ is shown as the following figure.
Figure 2-1 Front Panel of T3700G-28TQ
The front panel of T3700G-52TQ is shown as the following figure.
Figure 2-2 Front Panel of T3700G-52TQ
LEDs
LED
Indication
PWR1
PWR2
Green On: The power supply module connected to the corresponding power
slot works properly.
Yellow On: The power supply module connected to the corresponding power
slot works improperly.
Off: The corresponding power slot is not connected to any power supply
module.
8
LED
Indication
SYS
Flashing: The switch works properly.
On or Off: The switch works improperly.
FAN
Green On: All the fans work properly.
Yellow On: Not all the fans work properly.
Off: No fan module is connected to the switch.
Master
On: The switch works as master in the stack system, or does not join any stack
system.
Off: The switch works as member in the stack system.
Module
Green On: An Interface Card is connected to the switch and works properly.
Yellow On: An Interface Card is connected to the switch, but works improperly.
Off: No Interface Card is connected to the switch.
Console
On: Data is being transmitted or received.
Off: No data being transmitted or received for more than 6 minutes.
For T3700G-28TQ:
Link/Act (Port 1-24, MGMT)
For T3700G-52TQ:
Link/Act (Port 1-48, MGMT)
Green On: Running at 1000Mbps, but no activity.
Green Flashing: Running at 1000Mbps and is transmitting or receiving data.
Yellow On: Running at 10/100Mbps, but no activity.
Yellow Flashing: Running at 10/100Mbps and is transmitting or receiving data.
Off: No device is linked to the corresponding port.
For T3700G-28TQ:
25, 26
For T3700G-52TQ:
49, 50
On
:
An SFP+ transceiver/cable is connected to the corresponding port, and it is
connected to a 10Gbps device, but no activity.
Flashing
:
A 10Gbps device is connected to the corresponding port and
transmitting data.
Off
:
An SFP+ transceiver/cable is connected to the corresponding port, but it is
not connected to a device, or no SFP+ transceiver/cable is connected.
M1,M2
On: An SFP+ transceiver/cable is connected to the corresponding port of the
Interface Card, and it is connected to a 10Gbps device, but no activity.
Flashing: A 10Gbps device is connected to the corresponding port of the
Interface Card and transmitting data.
Off: No Interface Card is connected, or no SFP+ transceiver/cable is connected
to the installed Interface Card, or an SFP+ transceiver/cable is connected to the
corresponding port of the Interface Card, but it is not connected to a device.
9
2.2.2 Rear Panel
The rear panel of T3700G-28TQ is shown as the following figure.
Figure 2-3 Rear Panel (1) of T3700G-28TQ
The rear panel of T3700G-52TQ is shown as the following figure.
Figure 2-4 Rear Panel (1) of T3700G-52TQ
Note:
The Interface Card Slot and Power Supply Module2 are shipped with protective covers.
10/100/1000Mbps RJ45 Ports: Designed to connect to the device with a bandwidth of
10Mbps, 100Mbps or 1000Mbps. Each has a corresponding Link/Act LED.
SFP Port: Designed to install the SFP transceiver. These four SFP transceiver slots are
shared with the associated RJ45 ports. The associated two ports are referred as a “Combo”
port, which means they cannot be used simultaneously, otherwise only RJ45 port works.
The SFP ports support 1000M SFP module connection only.
SFP+ Port: Designed to install the 10Gbps SFP+ transceiver or SFP+ cables. T3700G-52TQ
also provides an interface card slot on the rear panel to install the expansion card (TX432 of
TP-Link for example). If TX432 is installed, you get another two 10Gbps SFP+ ports.
Console Port (USB/RJ-45): Designed to connect with the USB port of a computer for
monitoring and configuring the switch. The switch has an RJ-45 console port and a
micro-USB console port available. Console input is active on only one console port at a time.
By default, the micro-USB connector takes precedence over the RJ-45 connector.
Unit ID LED: Designed to display the stack Unit ID of the switch. For the switch that does
not join any stack system, it displays its default Unit ID. To modify the default unit number,
please logon to the GUI of the switch and go to Stack→Stack Management→Stack Config
page.
Interface Card Slot: Designed to extend the interfaces. You can select an Interface Card
(TX432 of TP-Link for example) for your switch if needed.
Grounding Terminal: The switch already comes with Lightning Protection Mechanism. You
can also ground the switch through the PE (Protecting Earth) cable of AC cord or with
Ground Cable. For detailed information, please refer to the Installation Guide.
10
USB 2.0 Interface: USB 2.0 interface is used to connecting peripheral equipment.
Management Port: Designed to connect to the device with a bandwidth of 10Mbps,
100Mbps or 1000Mbps. It has a corresponding MGMT LED on the front panel. You need
assign an IP address for the port to manage the switch.
RJ-45 Console Port: Designed to connect with the serial port of a computer or terminal for
monitoring and configuring the switch. The switch has an RJ-45 console port and a
micro-USB console port available. Console input is active on only one console port at a time.
By default, the micro-USB connector takes precedence over the RJ-45 connector.
Power Supply Module 1/2: One AC Power Supply Module PSM150-AC has been installed in
the switch. The malfunctioned PSM150-AC can be replaced with a TP-Link power supply
module of the same model. Its input voltage is 100-240V~ 50/60Hz.
The AC Power Supply Module is fully hot swappable, helping to ensure no system
interruption during installation or replacement. For how to install/remove the Power Supply
Module, please refer to Installation Guide.
With all the protective covers removed, and the Interface Card (TX432) & Power Supply Module
(PSM150-AC) inserted, the rear panel of T3700G-28TQ/T3700G-52TQ is shown as the
following figure.
Power
PS OK
Fault
PSM150-AC
100-240V~ 50/60Hz 2.5A
Power
PS OK
Fault
PSM150-AC
100-240V~ 50/60Hz 2.5A
M1
SFP+
M2
SFP+
CLASS 1LASER PRODUCT
TX432
Figure 2-5 Rear Panel (2) of T3700G-28TQ
Figure 2-6 Rear Panel (2) of T3700G-52TQ
Return to CONTENTS
11
Chapter 3 Login to the Switch
3.1 Login
1) To access the configuration utility, open a web-browser and type in the default address
http://192.168.0.1 in the address field of the browser, then press the Enter key.
Figure 3-1 Web-browser
Tips:
To log in to the switch, the IP address of your PC should be set in the same subnet addresses
of the switch. The IP address is 192.168.0.x ("x" is any number from 2 to 254), Subnet Mask is
255.255.255.0.
2) After a moment, a login window will appear, as shown in Figure 3-2. Enter admin for the User
Name and Password, both in lower case letters. Then click the Login button or press the
Enter key.
Figure 3-2 Login
3.2 Configuration
After a successful login, the main page will appear as Figure 3-3, and you can configure the
function by clicking the setup menu on the left side of the screen.
12
Figure 3-3 Main Setup-Menu
Note:
Clicking Apply can only make the new configurations effective before the switch is rebooted. If
you want to keep the configurations effective even the switch is rebooted, please click Save
Config. You are suggested to click Save Config before cutting off the power or rebooting the
switch to avoid losing the new configurations.
Return to CONTENTS
13
Chapter 4 System
The System module is mainly for system configuration of the switch, including five submenus:
System Info, User Management, System Tools, Access Security and SDM Template.
4.1 System Info
The System Info, mainly for basic properties configuration, can be implemented on System
Summary, Device Description, System Time, Daylight Saving Time, System IPv6,
Management Port IPv4 and Management Port IPv6 pages.
4.1.1 System Summary
On this page you can view the port connection status and the system information.
The port status diagram shows the working status of 44 10/100/1000Mbps RJ45 ports, 4
1000Mbps SFP ports and 4 10000Mbps SFP+ ports of the switch. Ports 45, 46, 47 and 48 are
Combo ports with SFP ports labeled 45F, 46F, 47F and 48F.
14
Choose the menu System → System Info → System Summary to load the following page.
Figure 4-1 System Summary
Port Status
UNIT： Select the unit ID of the desired member in the stack.
Indicates the 1000Mbps port is not connected to a device.
Indicates the 1000Mbps port is at the speed of 1000Mbps.
Indicates the 1000Mbps port is at the speed of 10Mbps or 100Mbps.
Indicates the SFP port is not connected to a device.
Indicates the SFP port is at the speed of 1000Mbps.
Indicates the SFP+ port is not connected to a device.
Indicates the SFP+ port is at the speed of 10000Mbps.
15
When the cursor moves on the port, the detailed information of the port will be displayed.
Figure 4-2 Port Information
Port Info
Port:
Displays the port number of the switch.
Type:
Displays the type of the port.
Rate:
Displays the maximum transmission rate of the port.
Status:
Displays the connection status of the port.
Click a port to display the bandwidth utilization on this port. The actual rate divided by
theoretical maximum rate is the bandwidth utilization. Figure 4-3 displays the bandwidth
utilization monitored every four seconds. Monitoring the bandwidth utilization on each port
facilitates you to monitor the network traffic and analyze the network abnormities.
Figure 4-3 Bandwidth Utilization
Bandwidth Utilization
Rx: Select Rx to display the band
width utilization of receiving
packets on this port.
Tx:
Select Tx to display the bandwidth utilization of sending packets
on this port.
4.1.2 Device Description
On this page you can configure the description of the switch, including device name, device
location and system contact.
Choose the menu System→ System Info→ Device Description to load the following page.
16
Figure 4-4 Device Description
The following entries are displayed on this screen:
Device Description
Device Name:
Enter the name of the switch.
Device Location:
Enter the location of the switch.
System Contact:
Enter your contact information.
4.1.3 System Time
System Time is the time displayed while the switch is running. On this page you can configure the
system time and the settings here will be used for other time-based functions like ACL.
You can manually set the system time, get UTC automatically if it has connected to an NTP
server or synchronize with PC’s clock as the system time.
Choose the menu System → System Info →System Time to load the following page.
Figure 4-5 System Time
The following entries are displayed on this screen:
Time Info
Current System Time:
Displays the current date and time of the switch.
17
Current Time Source:
Displays the current time source of the switch.
Time Config
Manual:
When this option is selected, you can set the date and time
manually.
Get Time from NTP
Server:
When this option is selected, you can configure the time zone
and the IP Address for the NTP Server. The switch will get
UTC automatically if it has connected to an NTP Server.
Time Zone: Select your local time.
Primary/Secondary NTP Server: Enter the IP a
ddress for
the NTP Server.
Update Rate: Specify the rate fe
tching time from NTP
server.
Synchronize with
PC’S Clock:
When this option is selected, the administrator PC’s
clock is
utilized.
Note:
1. The system time will be restored to the default when the switch is restarted and you need to
reconfigure the system time of the switch.
2. When Get Time from NTP Server is selected and no time server is configured, the switch will
get time from the time server of the Internet if it has connected to the Internet.
4.1.4 Daylight Saving Time
Here you can configure the Daylight Saving Time of the switch.
Choose the menu System → System Info → Daylight Saving Time to load the following page.
Figure 4-6 Daylight Saving Time
18
The following entries are displayed on this screen:
DST Config
DST Status:
Enable or disable DST.
Predefined Mode: Select a predefined DST configuration:
USA: Second Sunday in March, 02:00 ~ First Sunday in
November, 02:00.
Europe: Last Sunday in March, 01:00 ~ Last Sunday in
October, 01:00.
Recurring Mode: Specify t
he DST configuration in recurring mode. This
configuration is recurring in use:
Offset: Specify the time adding in minutes when Daylight
Saving Time comes.
Start/End Time: Select starting time and ending time of
Daylight Saving Time.
Date Mode: Specify th
e DST configuration in Date mode. This
configuration is one-off in use:
Offset: Specify the time adding in minutes when Daylight
Saving Time comes.
Start/End Time: Select starting time and ending time of
Daylight Saving Time.
Note:
When the DST is disabled, the predefined mode, recurring mode and date mode cannot be
configured.
4.1.5 System IPv6
On this page you can configure IPv6 address on the switch and login the switch through the
address to access the IPv6 applications. Internet Protocol Version 6 (IPv6), also called IP next
generation (IPng), is designed by the Internet Engineering Task Force (IETF) as the successor to
Internet Protocol Version 4 (IPv4). The significant difference between IPv6 and IPv4 is that IPv6
increases the IP address size from 32 bits to 128 bits.
19
Choose the menu System → System Info → System IPv6 to load the following page.
Figure 4-7 System IPv6
The following entries are displayed on this screen:
Gobal Config
IPv6:
Enable or disable IPv6 function globally on the switch.
Interface:
Choose the interface ID to set IPv6 function. You can set
interface type as VLAN Port or Routed Port.
20
Link-local Address Config
Config Mode: Select the link-local address configuration mode.
Manual: When this option is selected, you should assign
a link-local address manually.
Auto:
When this option is selected, the switch will
generate a link-local address automatically.
Link-local Address:
Enter a link-local address.
Status: Displays the status of the link-local address.
Normal: Indicates that the link-local address is normal.
Try: Indicates that the link-
local address may be newly
configured.
Repeat: Indicates that the link-
local address is duplicate.
It is illegal to access the switch using the IPv6 address
(including link-local and global address).
Global Address Autoconfig via RA Message
Enable global address
auto configuration via
RA message:
When this option is enabled, the switch automatically
configures a global address and other information according
to the address prefix and other
configuration parameters
from the received RA (Router Advertisement) message.
Global Address Autoconfig via DHCPv6 Server
Enable global address
auto configuration via
DHCPv6 Server:
When this option is enabled, the system will try to obtain the
global address from the DHCPv6 Server.
Add a Global Address Manually
Address Format:
You can select the global address format according to your
requirements.
EUI-
64: Indicates that you only need to specify an
address prefix, and then the system will create a global
address automatically.
Not EUI-
64: Indicates that you have to specify an intact
global address.
Global Address: When selecting the mode of EUI-
64, please input the address
prefix here, otherwise, please input an intact IPv6 address
here.
IPv6 Gateway Configuration
IPv6 Gateway:
Choose whether to set the IPv6 gateway address.
IPv6 Gateway
Address:
Enter the IPv6 gateway address.
21
Global Address Table
Select:
Select the desired entry to delete or modify the
corresponding global address.
Global Address:
Modify the global address.
Prefix Length:
Modify the prefix length of the global address.
Type
：
Displays the configuration mode of the global address.
Manual:
Indicates that the corresponding address is
configured manually.
Auto: Indicates that the corres
ponding address is
created automatically using the RA message or obtained
from the DHCPv6 Server.
Preferred Lifetime：
Displays the preferred time of the global address.
Valid Lifetime：
Displays the valid time of the global address.
Status
：
Displays the status of the global address.
Normal: Indicates that the global address is normal.
Try:
Indicates that the global address may be newly
configured.
Repeat:
Indicates that the corresponding address is
duplicate. It is illegal to access the switch using this
address.
4.1.6 Management Port IPv4
The Management Port is a dedicated Ethernet port for out-of-band management of the device.
Traffic on this port is segregated from operational network traffic on the switch ports and
cannot be switched or routed to the operational network. Use this page to configure network
information on the management port.
Choose the menu System → System Info → Management Port IPv4 to load the following page.
Figure 4-8 Management Port IPv4
22
The following entries are displayed on this screen:
IPv4 Protocol Configuration
IPv4 Protocol:
Specify IPv4 Address allocate mode of the management port.
None: Setup manually.
DHCP: Allocated through DHCP.
DHCP Client-ID: The DHCP Client-ID (Option 61) i
s used by DHCP clients to
specify their unique identifier. This value is expected to be
unique for all clients in an administrative domain.
IP Address:
Specify the IP address of the interface when the
Management Port Configuration Protocol is None.
Subnet Mask:
Specify the Subnet Mask of the interface when the
Management Port Configuration Protocol is None.
Gateway:
Specify the Gateway of the interface when the Management
Port Configuration Protocol is None.
IPv4 Address List
Select:
Select the interfaces to modify or delete.
IPv4 Protocol:
Specify IPv4 Address allocate mode of the management port.
None: Setup manually.
DHCP: Allocated through DHCP.
IP Address:
Specify the IP address of the interface when the
Management Port Configuration Protocol is None.
Subnet Mask:
Specify the Subnet Mask of the interface when the
Management Port Configuration Protocol is None.
Gateway:
Specify the Gateway of the interface when the Management
Port Configuration Protocol is None.
Status:
Displays interface current working status: up or down.
4.1.7 Management Port IPv6
The Management Port is a dedicated Ethernet port for out-of-band management of the device.
Traffic on this port is segregated from operational network traffic on the switch ports and
cannot be switched or routed to the operational network. Use this page to configure IPv6
network information on the management port.
Choose the menu System → System Info → Management Port IPv6 to load the following page.
23
Figure 4-9 Management Port IPv6
The following entries are displayed on this screen:
IPv6 Configuration
IPv6:
Enable or disable IPv6 function globally on the management
port.
IPv6 Protocol:
Specify IPv6 network information allocate mode of the
management port.
None: Setup manually.
DHCP: Allocated through DHCP.
DHCPv6 Client DUID: The client identifier used by the DHCPv6 client
(if enabled)
when sending messages to the DHCPv6 server.
AutoConfig:
Choose whether to allow to enable the IPv6 stateless
address autoc
onfiguration mode via the RA message on the
management port.
Add a IPv6 Address
Address Format:
You can select the IPv6 address format according to your
requirements.
EUI-
64: Indicates that you only need to specify an
address prefix, and then the system will create a IPv6
address automatically.
Not EUI-
64: Indicates that you have to specify an intact
IPv6 address.
24
IPV6 Address: When selecting the mode of EUI-
64, please input the address
prefix here, otherwise, please input an intact IPv6 address
here.
IPv6 Gateway Configuration
IPv6 Gateway:
Choose whether to set the IPv6 Gateway Address.
IPv6 Gateway
Address:
Please input the IPv6 gateway address here.
IPv6 Address List
Select:
Select the interfaces to modify or delete.
IPv6 Address Type:
Displays IPv6 Address type: Link Local, Global or Router.
IPv6 Prefix:
Displays the IPv6 prefix.
Prefix Length:
Displays the prefix length of IPv6 Address.
4.2 User Management
User Management functions to configure the user name and password for users to log on to
the Web management page with a certain access level so as to protect the settings of the
switch from being randomly changed.
The User Management function can be implemented on User Table and User Config pages.
4.2.1 User Table
On this page you can view the information about the current users of the switch.
Choose the menu System → User Management → User Table to load the following page.
Figure 4-10 User Table
4.2.2 User Config
On this page you can configure the access level of the user to log on to the Web management
page. The switch provides two access levels: Guest and Admin. The guest only can view the
settings without the right to configure the switch; the admin can configure all the functions of
the switch. The Web management pages contained in this guide are subject to the admin’s login
without any explanation.
25
Choose the menu System → User Management → User Config to load the following page.
Figure 4-11 User Config
The following entries are displayed on this screen:
User Info
User Name:
Create a name for users’ login.
Access Level: Select the access level to login.
Guest:
Guest only can view the settings without the right to
edit and modify.
Admin:
Admin can edit, modify and view all the settings of
different functions.
Password:
Type a password for users’ login.
Confirm Password:
Retype the password.
User Table
Select:
Select the desired entry to delete the corresponding user
information. It is multi-optional.
The current user information
cannot be deleted.
User ID,
User Name
and Access Level:
Displays the current user ID, user name and access level.
Operation: Click the Edit
button of the desired entry, and you can edit the
corresponding user information. After modifying the settings,
please click the Apply
button to make the modification
effective.
4.3 System Tools
The System Tools function, allowing you to manage the configuration file of the switch, can be
implemented on Boot Config, Config Restore, Config Backup, Firmware Upgrade, System
Reboot and System Reset pages.
26
4.3.1 Boot Config
On this page you can configure the boot file and the configuration file of the switch. When the
switch is powered on, it will start up with the startup image. If the startup fails, the switch will try
to start up with the backup image. If this startup fails too, the switch will changes to bootutil
state, in which circumstance the switch’s Web interface is unavailable and you can enter into
the bootutil menu of the switch through the console connection.
When the startup process is finished, the switch will read the startup-config file. If it fails, the
switch will try to read the backup-config file. If it fails too, the switch will be restored to factory
settings.
Choose the menu System → System Tools → Boot Config to load the following page.
Figure 4-12 Boot Config
The following entries are displayed on this screen:
Boot Table
Select:
Select the unit(s).
Unit:
Displays the unit ID.
Current Startup
Image:
Displays the current startup image.
Next Startup Image:
Select the next startup image.
Backup Image:
Select the backup boot image.
Image Table
Image Name:
The name of the image.
Flash Version:
The flash version of the image.
27
Software Version:
The software version of the image.
4.3.2 Config Restore
On this page you can upload a backup configuration file to restore your switch to this previous
configuration.
Choose the menu System → System Tools → Config Restore to load the following page.
Figure 4-13 Config Restore
The following entries are displayed on this screen:
Config Restore
Import: Click the Import button to restore the backup configuration file.
It will take effect after the switch automatically reboots.
Note:
1. It will take a few minutes to restore the configuration. Please wait without any operation.
2. To avoid any damage, please don’t power down the switch while being restored.
3. After the configuration file is restored successfully, the device will reboot to make the
configuration change effective.
4. Wrong uploaded configuration file may cause the switch unmanaged.
4.3.3 Config Backup
On this page you can download the current configuration of the specified unit in the stack and
save it as a file to your computer for your future configuration restore.
Choose the menu System → System Tools → Config Backup to load the following page.
Figure 4-14 Config Backup
28
The following entries are displayed on this screen:
Config Backup
Export: Click the Export
button to save the current configuration as a
file to your computer.
You are suggested to take this measure
before upgrading.
Note:
1. It will take a few minutes to backup the configuration. Please wait without any operation.
2. Check the checkbox to copy running-config to startup-config before exporting the
startup-config.
4.3.4 Firmware Upgrade
The switch system can be upgraded via the Web management page. To upgrade the system is
to get more functions and better performance. Go to http://www.tp-link.com to download the
updated firmware.
Choose the menu System → System Tools → Firmware Upgrade to load the following page.
Figure 4-15 Firmware Upgrade
Note:
1. Don’t interrupt the upgrade.
2. Upgrading the firmware will only upgrade the backup image.
3. You are suggested to back up the configuration before upgrading.
4. Please select the proper software version matching with your hardware to upgrade.
5. To avoid damage, please don't turn off the device while upgrading.
6. After upgrading, the device will reboot automatically.
4.3.5 System Reboot
On this page you can reboot the specified unit switch in the stack and return to the login page.
Please save the current configuration before rebooting to avoid losing the configuration
unsaved.
29
Choose the menu System → System Tools → System Reboot to load the following page.
Figure 4-16 System Reboot
Note:
To avoid damage, please don't turn off the device while rebooting.
4.3.6 System Reset
On this page you can reset the specified unit in the stack to the default. All the settings will be
cleared after the switch is reset.
Choose the menu System → System Tools → System Reset to load the following page.
Figure 4-17 System Reset
Note:
The System Reset option will restore the configuration to default and your current settings will
be lost.
4.4 Access Security
Access Security provides different security measures for the remote login so as to enhance
the configuration management security. It can be implemented on Access Control, HTTP
Config, HTTPS Config, SSH Config and Telnet Config pages.
4.4.1 Access Control
On this page you can control the users logging on to the Web management page to enhance
the configuration management security. The definitions of Admin and Guest refer to 4.2 User
Management. This function only applies to Web, SNMP, Telnet, SSL and SSH.
30
Choose the menu System → Access Security → Access Control to load the following page.
Figure 4-18 Access Control
The following entries are displayed on this screen:
Access Control Config
Control Mode:
Select the control mode for users to log on to the Web
management page.
Disable: Select to disable Access Control function.
IP-based: Select this option to limit the IP-
range of the users
for managing the switch.
MAC-based:
Select this option to limit the MAC Address of
the users for managing the switch.
Port-based: Select this option to limit the ports for
managing the switch.
Access Interface:
Select the interface for Access Control to apply.
IP Address& Mask
：
These fields can be available for configuration only when
IP-based mode is selected. Only the users within the IP-
range
you set here are allowed for managing the switch.
MAC Address:
The field can be available for configuration only when
MAC-
based mode is selected. Only the user with this MAC
Address you set here is allowed for managing the switch.
Port: The field can be available for configurat
ion only when
Port-
based mode is selected. Only the users connected to
these ports you set here are allowed for managing the switch.
4.4.2 HTTP Config
With the help of HTTP (Hyper Text Transfer Protocol), you can manage the switch through a
standard browser. The standards development of HTTP was coordinated by the Internet
Engineering Task Force and the World Wide Web Consortium.
On this page you can configure the HTTP function.
31
Choose the menu System → Access Security → HTTP Config to load the following page.
Figure 4-19 HTTP Config
The following entries are displayed on this screen:
Global Config
HTTP:
Enable or disable the HTTP function on the switch.
Session Config
Hard Timeout:
Configure hard timeout of HTTP sessions.
Soft Timeout:
Configure soft timeout of HTTP sessions.
Maximum Sessions:
Configure maximum allowable number of HTTP sessions.
4.4.3 HTTPS Config
SSL (Secure Sockets Layer), a security protocol, is to provide a secure connection for the
application layer protocol (e.g. HTTP) communication based on TCP. SSL is widely used to
secure the data transmission between the Web browser and servers. It is mainly applied
through ecommerce and online banking.
SSL mainly provides the following services:
1. Authenticate the users and the servers based on the certificates to ensure the data are
transmitted to the correct users and servers;
2. Encrypt the data transmission to prevent the data being intercepted;
3. Maintain the integrality of the data to prevent the data being altered in the transmission.
Adopting asymmetrical encryption technology, SSL uses key pair to encrypt/decrypt
information. A key pair refers to a public key (contained in the certificate) and its corresponding
private key. By default the switch has a certificate (self-signed certificate) and a corresponding
private key. The Certificate/Key Download function enables the user to replace the default key
pair.
After SSL is effective, you can log on to the Web management page via https://192.168.0.1. For
the first time you use HTTPS connection to log into the switch with the default certificate, you
will be prompted that “The security certificate presented by this website was not issued by a
32
trusted certificate authority” or “Certificate Errors”. Please add this certificate to trusted
certificates or continue to this website.
The switch also supports HTTPS connection for IPv6. After configuring an IPv6 address (for
example, 3001::1) for the switch, you can log on to the switch’s Web management page via
https://[3001::1].
On this page you can configure the HTTPS function.
Choose the menu System → Access Security → HTTPS Config to load the following page.
Figure 4-20 HTTPS Config
The following entries are displayed on this screen:
Global Config
HTTPS:
Enable or disable the HTTPS function on the switch.
33
SSL Version 3: Enable or d
isable Secure Sockets Layer Version 3.0. By default,
it’s enabled.
TLS Version 1: Enable or disable
Transport Layer Security Version 1.0. By
default, it’s enabled.
CipherSuite Config
RSA_WITH_RC4_128_MD5: Key exchange with RC4 128-
bit encryption and
MD5 for message digest. By default, it’s enabled.
RSA_WITH_RC4_128_SHA: Key exchange with RC4 128-bit
encryption and
SHA for message digest. By default, it’s enabled.
RSA_WITH_DES_CBC_SHA: Key exchange with DES-
CBC for message
encryption and SHA for message digest. By
default, it’s enabled.
RSA_WITH_3DES_EDE_CBC_SHA: Key exchange with 3DES and DES-EDE3-C
BC
for message encryption and SHA for message
digest. By default, it’s enabled.
Session Config
Hard Timeout:
Configure hard timeout of HTTP sessions.
Soft Timeout:
Configure soft timeout of HTTP sessions.
Maximum Sessions:
Configure maximum allowable number of HTTP sessions.
Certificate and Key Management
You can get the status of the DSA and RSA keys, which can also be generated or deleted
here with the Generate and Delete buttons.
Certificate and Key:
The status of SSL certificate and key file (PEM
Encoded) on the
device, which might be Present or Absent.
Certificate Download
Certificate File:
Select the desired certificate to download to the switch. The
certificate must be BASE64 encoded.
Key Download
Key File: Select the desired key to download
to the switch. The key must
be BASE64 encoded.
Note:
1. HTTPS function cannot be enabled until the SSL certificate and key are present.
2. The SSL certificate and key downloaded must match each other; otherwise the HTTPS
connection will not work.
34
3. To establish a secured connection using https, please enter https:// into the URL field of
the browser.
4. It may take more time for https connection than that for http connection, because https
connection involves authentication, encryption and decryption etc.
4.4.4 SSH Config
As stipulated by IETF (Internet Engineering Task Force), SSH (Secure Shell) is a security
protocol established on application and transport layers. SSH-encrypted-connection is similar
to a telnet connection, but essentially the old telnet remote management method is not safe,
because the password and data transmitted with plain-text can be easily intercepted. SSH can
provide information security and powerful authentication when you log on to the switch
remotely through an insecure network environment. It can encrypt all the transmission data and
prevent the information in a remote management being leaked.
Comprising server and client, SSH has two versions, V1 and V2 which are not compatible with
each other. In the communication, SSH server and client can auto-negotiate the SSH version
and the encryption algorithm. After getting a successful negotiation, the client sends
authentication request to the server for login, and then the two can communicate with each
other after successful authentication. This switch supports SSH server and you can log on to
the switch via SSH connection using SSH client software.
SSH key can be downloaded into the switch. If the key is successfully downloaded, the
certificate authentication will be preferred for SSH access to the switch.
35
Choose the menu System → Access Security → SSH Config to load the following page.
Figure 4-21 SSH Config
The following entries are displayed on this screen:
Global Config
SSH:
Enable or disable SSH function.
Protocol V1:
Enable or disable SSH V1 to be the supported protocol.
Protocol V2:
Enable or disable SSH V2 to be the supported protocol.
Idle Timeout:
Specify the idle timeout time. The system will automatically
release the connection when the time is up. The default time is
120 seconds.
Max Connect:
Specify the maximum number of the connections to the SSH
server. No new connection will be established when the number
of the connections reaches the maximum number you set. The
default value is 5.
36
Encryption Algorithm
Configure SSH encryption algorithms.
AES128-CBC: Select the checkbox to enable the AES128-
CBC algorithm of
SSH.
AES192-CBC: Select the checkbox to enable the AES192-
CBC algorithm of
SSH.
AES256-CBC: Select the checkbox to enable the AES256-
CBC algorithm of
SSH.
Blowfish-CBC: Select the checkbox to enable the Blowfish-
CBC algorithm of
SSH.
Cast128-CBC: Select the checkbox to enable the Cast128-
CBC algorithm of
SSH.
3DES-CBC:
Select the checkbox to enable the 3DES-CBC algorithm of SSH.
Data Integrity Algorithm
Configure SSH data integrity algorithms.
HMAC-SHA1: Select the checkbox to enable the HMAC-
SHA1 algorithm of
SSH.
HMAC-MD5: Select the checkbox to enable the HMAC-
MD5 algorithm of
SSH.
Key Management
You can get the status of the DSA and RSA keys, which can also be generated or deleted
here with the Generate and Delete buttons.
DSA: The status of SSH-2 DSA key file (PEM Encoded) on the device,
which might be Present or Absent.
RSA: The status of SSH-1 RSA or SSH-
2 RSA key file (PEM Encoded)
on the device, which might be Present or Absent.
Download: Click the Download
button to download the desired key file to
the switch.
Key Download
Key Type:
Select the type of SSH Key to download. The switch supports
two types: SSH-2 RSA/DSA and SSH-1 RSA.
Key File:
Please ensure the key length of the downloaded file is in the
range of 512 to 3072 bits.
Download: Click the Download
button to download the desired key file to
the switch.
37
Note:
1. It will take a long time to download the key file. Please wait without any operation.
2. After the Key File is downloaded, the user's original key of the same type will be replaced.
Application Example for SSH:
Network Requirements
1. Log on to the switch via password authentication using SSH and the SSH function is
enabled on the switch.
2. PuTTY client software is recommended.
Configuration Procedure
1. Open the software to log on to the interface of PuTTY. Enter the IP address of the switch
into Host Name field; keep the default value 22 in the Port field; select SSH as the
Connection type.
38
2. Click the Open button in the above figure to log on to the switch. Enter the login user name
and password, and then you can continue to configure the switch.
4.4.5 Telnet Config
On this page you can enable or disable Telnet function globally on the switch.
Choose the menu System → Access Security → Telnet Config to load the following page.
Figure 4-22 Access Control
The following entries are displayed on this screen:
Global Config
Telnet:
Enable or disable Telnet function globally on the switch.
4.5 SDM Template
SDM (Switch Database Management) provides different templates for users to efficiently
manage the hardware TCAM resources. Users can select the appropriate template according
to the application environment.
4.5.1 SDM Template Config
On this page you can configure and view the SDM templates on the switch.
39
Choose the menu System → SDM Template → SDM Template Config to load the following
page.
Figure 4-23 SDM Template Config
Select Options
Current Template
ID:
Displays the SDM template currently in use.
Next Template ID: Displays t
he SDM template that will become active after a
reboot.
Select Next
Template:
Configure the SDM template that will become active after the
next reboot.
Template Table
SDM Template:
Displays the template name.
ARP Entries: The maximum number of entries i
n the IPv4 Address Resolution
Protocol (ARP) cache for routing interfaces.
IPv4 Unicast Routes:
The maximum number of IPv4 unicast forwarding table entries.
IPv6 NDP Entries: The maximum number of
IPv6 Neighbor Discovery Protocol
(NDP) cache entries.
ECMP Next Hops:
The maximum number of next hops that can be installed in the
IPv4 and IPv6 unicast forwarding tables.
IPv4 Multicast
Routes:
The maximum number of IPv4 multicast forwarding table
entries.
IPv6 Multicast
Routes:
The maximum number of IPv6 mu
lticast forwarding table
entries.
Return to CONTENTS
40
Chapter 5 Stack
The stack technology is to connect multiple stackable devices through their stack ports,
forming a stack which works as a unified system and presents as a single entity to the network
in Layer 2 and Layer 3 protocols. It enables multiple devices to collaborate and be managed as
a whole, which improves the performance and simplifies the management of the devices
efficiently.
Advantages
The stack delivers the following benefits:
1. Simplified management. After stack establishment, the user can log in the stack system
through any stack ports of stackable devices, and manage it as a single device. You only
need to configure the stack system once instead of operating repetitive configuration on
multiple devices. Various ways such as CONSOLE, SNMP, TELNET and WEB are available
for users to manage the stack.
2. High reliability. The stack is highly reliable in following aspects:
1） The stack system is comprised of multiple devices among which one member device
works as the stack master to take charge of the operation, management and
maintenance of the stack, while the other stack members process services and keep a
copy configuration file in accordance with the master for providing backup
simultaneously. Once the stack master becomes unavailable, the remaining stack
members elect a new master among themselves instantly and automatically, which can
ensure uninterrupted services and furthermore making 1:N backup feasible. Due to the
real-time configuration and data synchronization being strictly executed, the new
master can take over the previous master to manage and maintain the stack system
smoothly without affecting its normal operation.
2） Distributed LACP (Link Aggregation Control Protocol) supports link aggregation across
devices. Since the whole stack system presents as a single device on the network,
external devices can implement LACP with the stack system by connecting to several
stack member devices simultaneously. Among the links between the stack system and
external devices, load distribution and backup can be realized to increase the reliability
of the stack system and to simplify dramatically the network topology as Figure 5-1
shows.
41
Figure 5-1 Distributed LACP
In a ring connected stack, it can still operate normally by transforming into a daisy
chained stack when link failure occurs, which further ensures the normal operation of
load distribution and backup across devices and links as Figure 5-2 shows.
Figure 5-2 Load Distribution and Backup across Devices
3. Network scalability. Each member device in the stack system is able to process protocol
packets and forward data individually, which enables you to increase the port number and
bandwidth of the stack system by adding new member devices. The users are free to add
or remove stack members without affecting the normal running of the stack, which enables
them to protect the existed resources furthest during network upgrades.
42
Application Diagram
Figure 5-3 Application Diagram
Stack Introduction
1. Stack Elements
1） Stack Role
Each device in the stack system is called stack member. Each stack member processes
services packets and plays a role which is either master or member in the stack system.
The differences between master and member are described as below:
• Master: Indicates the device is responsible for managing the entire stack system.
• Member: Indicates the device provides backup for the master. If the master fails, the
stack will elect a new master from the remaining members to succeed the previous
master.
2） Stack Event
Stack event indicates the global events which might happen during stack operation
process, with two options:
• Merge: It occurs when two independent stacks merge into one stack because of stack
link establishment, as shown in the following figure:
Figure 5-4 Stack Merge
43
When stack merge occurs, the previous masters compete to be the new master. The
stack members of the defeated stack will join the winner stack as a member to form a
new stack. Master will assign Unit Number to the newly joined members and compare
their configuration files. The members with different configurations files with the master
will download the configuration files of the master and re-configure.
• Split: It occurs when stack splits into two or more stacks because of stack link failures,
as shown in the following figure:
Figure 5-5 Stack Split
After stack partition occurs, each newly established stack elects their own new master
and use the MAC address of the master as its stack MAC address. However, stack
partition probably brings about routing and forwarding problems on the network since
the partitioned stacks keep operating with the previous IP address by default, which
results in same IP address being reused in the same LAN.
2. Operation Procedure
Stack management involves these four stages: Connecting the stack members, Topology
collection, Master election, and Stack management and maintenance.
1） Connecting the stack members
To establish a stack, please physically connect the stack ports of the member devices with
cables. The stack ports of T3700G-52TQ can be used for stack connection or as normal
Ethernet Gigabit port. When you want to establish a stack, the stack mode of the related
ports should be configured as "Enable". If the stack mode of the port is "Disable", then the
port will work as a normal Ethernet port.
Stack typically adopts a daisy chain topology or ring topology as shown in Figure 5-6:
Figure 5-6 Stack Connect Topology
44
• The daisy chain topology is mainly used in a network where member devices are
distributively located.
• The ring topology is more reliable than the daisy chain topology. In a daisy chained
stack, link failure can cause stack split. While in a ring connected stack, the system is
able to operate normally with a new daisy chained topology.
Note:
Establish a stack of ring or daisy chain topology with eight T3700G-28TQ/T3700G-52TQ
switches at most.
2） Topology Collection
Each member in the stack collects the topology of the whole stack by exchanging stack
discovery packets with its neighbors. Discovery packet carries topology information
including stack port connection status, unit number, priorities, MAC addresses, etc.
Each member keeps a local record of the known topology information. When the device
initializes, it only possesses the record of its own topology information. Periodically the
stack members send out their known topology information through the stack ports to its
neighbors. When the neighbors receive the information, they will update their local
topology information. After a period of time of broadcasting and updating information, all
the stack members can collect the complete topology information (known as topology
convergence).
Then the switch enters the master election stage.
3） Master Election
After all members have obtained topology information (known as topology convergence),
the stack enters the master election stage. A stack always has one stack master, while the
other stack members are members. Master election determines the stack role of the stack
members.
Master election is held each time the topology changes, for example, when stack merge or
split occurs, or the stack or the current master is reset.
The master is elected based on the following rules and in the order listed:
1. The switch that is currently the stack master.
2. The switch with the highest stack member priority value.
3. The switch with the lowest MAC address.
After master election, the stack forms and enters into stack management and
maintenance stage.
Note:
1. The priority value ranges from 1 to 15. The higher the value is, the more likely the
member will be elected as the master. By default, the member priority of the switch is 5.
We recommend you manually assign the highest priority value to the switch that you
prefer to be the stack master before stack establishment.
45
2. The switch is non-preemptible when it joins the stack in cold-start mode, and the
process is illustrated as bellow: the switch has no stack role at its start, and it sends out
discovery messages to collect the topology of the current stack system. After the
topology collection, the switch obtains its role according to the rules above. The switch
will become stack member if there is already a master in the stack. The master will
resume its role even if the newly joined switch has a higher priority.
4） Stack Management and Maintenance
After the stack is established, all the stack members are integrated into a virtual device in
the network and managed by the master. The following section briefly introduces the
concepts and rules involved in stack management stage.
• Unit Number: When the stack is running, unit number is used to identify and manage
member devices. Unit number is unique in a stack system. The factory default unit
number of switch is 1. In order to keep its uniqueness, before establishing stack you are
kindly recommended to prepare a unit number assignment scheme and then manually
configure it on each member device.
During unit number assignment process, the master prioritizes the member devices
already carrying manually assigned unit number. If the unit number has not been used
by other stack members the member device will keep it. Otherwise, the unit number is
configured based on the following rules and in the order listed:
1. The device which was managed by the current master before the configuration will
resume its unit number.
2. The device with manually assigned unit number is prior to the device whose unit
number assignment mode is “Auto”.
3. The device with the highest stack member priority value.
4. The device with the lowest MAC address.
Note:
1. You can get the current unit number of the switch from the unit number LED on the
front panel of the switch.
2. When the stack is running, if you want to change the unit number manually, only the
unit numbers which have not been occupied by the other member devices are
available for you to choose from.
• Port Number Format:
The format of port number should be Unit Number/Slot Number/Port Number. Among
them:
(1) Unit Number: The default unit number of the switch is 1. If a device has joined
stack system, the unit number which the device possesses in the stack system
will be kept using as its unit number after the device leaves the stack system.
(2) Slot Number: Indicates the number of the slot the interface card is in. For
T3700G-52TQ, the front panel ports belong to slot 0. Slot number starting from 1
each represents an interface card slot.
46
(3) Physical Port Number: The physical port number on the switch which can be
obtained through the front panel of the switch.
For instance: Port number 2/0/3 indicates the physical port3 on the switch whose unit
number is 2.
• Configuration Files Application Rules: It includes global configuration and interface
configuration two parts.
(1) The global configurations of all stack members are the same. Besides, each
member device keeps pace with the global configuration of the master device
which enables the stack system to work just like a single entity in the network. The
stack system adopts the following methods to ensure the synchronization of
global configuration files:
When the stack initializes, the master device will compare the configuration files
of each stack member and reconfigure the device whose global configuration is
different from its own, so as to ensure the global configuration of the stack
members are exactly the same.
When the stack is work normally, any global configuration of users will be
recorded to the current configuration files of master and then be synchronized to
the other members in the stack.
(2) Each stack member only saves the configuration of its own ports. Even when user
sets the configuration for all ports, the configuration will also be saved and
implemented only on the related stack member which the ports belong to.
• Stack Maintenance
Stack maintenance mainly functions to monitor the join and leave of member devices,
collect the new topology at any times and maintain the current topology.
When the stack is operating normally, packets are transmitted constantly between
stack members. The switch can quickly judge the link status of the stack port via
monitoring the response of the packets. When the switch detects the link status
changes, it will recollect system topology and update topology database to ensure the
normal operation of the stack.
The events that will change the link status of the stack port which thus affecting the
system topology include: stack member failure or leave, new member's coming, link
failure or failure recovery, etc.
When the master switch fails, the stack system elects a new master from the remaining
members to succeed the previous master.
5.1 Stack Management
Before configuring the stack, we highly recommend you to prepare the configuration planning
with a clear set of the role and function of each member device. Some configuration needs
device reboot to take effect, so you are kindly recommended to configure the stack at first,
next connect the devices physically after powering off them, then you can power them on and
the devices will join the stack automatically. After stack is established, users can log in the
stack system through any member devices to configure and manage it.
47
The stack management can be implemented on Stack Info, Stack Config and Auto Copy
Software pages.
5.1.1 Stack Info
On this page you can view the basic parameters of the stack function. Choose the menu Stack
→ Stack Management → Stack Info to load the following page.
Figure 5-7 Stack Info
Configuration Procedure:
View the basic parameters of the stack function.
Entry Description:
Auto Copy Software
Synchronization:
Displays the status of the Auto Copy Software function.
48
SNMP Trap status: Displays the SNMP trap
status of the Auto Copy Software
function.
Allow Downgrade: Displays t
he status of allowing downgrade of the new members
in the Auto Copy Software function.
Stack Member Info
UNIT:
Displays the unit number of the switch.
Role: Displays
the stack role of the switch in the stack. There are two
options: Master and Member.
Priority:
Displays the member priority of the switch. The higher the value
is, the more likely the member will be elected as the master.
State:
Displays the state of the switch.
MAC Address
Displays the unique identification of the switch.
Preconfigured
Device Type:
Displays the device type of the pre-configured switch.
Plugged-in Device
Type:
Displays the device type of the plugged-in switch.
Switch Description:
Displays the description of the switch.
Version:
Displays the current software version of the switch.
SFS Last Attempt
Status:
Displays the status of the last stack firmware synchronization.
Up Time:
Displays the system up time of the switch.
Stack Port Info:
Stack Port:
Displays the stack port number.
Type:
Displays the transceiver type of the stack port
Product Name:
Displays the transceiver product name of the stack port.
Configured Stack
Mode：
Displays the configured mode of the stack port.
Running Stack
Mode：
Displays the running mode of the stack port.
Link Status：
Displays the link status of the stack port.
Link Speed:
Displays the link speed of the stack port.
Neighbor: Displays the unit id of the switch directly linked
on the stack
port.
5.1.2 Stack Config
On this page you can configure the basic parameters of the stack function.
49
Choose the menu Stack → Stack Management → Stack Config to load the following page.
Figure 5-8 Stack Config
Configuration Procedure:
1) Set the role of a specified switch in the stack.
2) Configure the provisioned member switch.
3) Configure the Unit ID and Priority for the Stack Member.
4) Configure the SFP+ port’s stacking feature.
Entry Description:
Role Config
Master：
Set the switch as master.
Standby Member：
Set the switch as standby member.
Provision Info
Unit ID：
Configure the switch number of the provisioned switch.
Device Type：
Configure the switch type of the provisioned switch.
Stack Member Config
Unit ID：
Displays the switch number of the provisioned switch.
Role：
Displays the role of the switch in the stack: master or member.
50
Standby Status:
Displays the standby status of the switch.
New Unit ID:
Configure a new unit number of the switch.
Priority: Con
figure the priority used in master election. Large first. The
priority change will not take effect until next election.
Preconfigured
Device Type:
Displays the switch type of the provisioned switch.
Plugged-
in Device
Type:
Displays the device type of the plugged-in switch.
State:
Displays the state of the switch.
Version:
Displays the software version of the switch.
Stack Port Config
Select：
Select the SFP+ port.
Stack Port：
Displays the ports that can be configured as stack ports.
Configured Stack
Mode :
Configure the SFP+ port to be an Ethernet port or a stack port.
Running Stack
Mode:
Displays whether the port is an Ethernet port or a
stack port at
the moment.
Link Status:
Displays the link status of the stack port.
Link Speed (Gb/s):
Displays the link speed of the stack port.
Neighbor:
The unit id of the switch directly links on the stack port.
5.1.3 Auto Copy Software
To resolve the code mismatch in stack attaching, the new members will copy software from the
master.
Choose the menu Stack → Stack Management → Auto Copy Software to load the following
page.
Figure 5-9 Auto Copy Software
Configuration Procedure:
View and configure the Auto Copy Software function.
Entry Description:
Synchronization:
Enable or disable the Auto Copy Software function.
51
SNMP Trap status: Enable or dis
able SNMP trap of the Auto Copy Software
function.
Allow Downgrade: Enable or dis
able downgrade of the new members in the Auto
Copy Software function. If you choose en
able, the member’s
software version is allowed to downgrade when copying
software from the master.
5.2 Application Example for Stack
Network Requirements
Establish a stack of ring topology with four T3700G-52TQ switches.
Network Diagram
Configuration Procedure
Configure switch A, B, C and D before physically connecting them:
Step
Operation
Description
1
Configure stack mode. Required. On Stack Management → Stack Config page,
configure the port’s stack mode as "Stack" in Stack Port
Config section.
2
Configure unit ID. Optional. On Stack Management → Stack Config page,
configure the unit ID of switch A, B, C and D as 1, 2, 3 and 4
respectively in Stack Member Config section.
3
Configure the role of
the switch in the stack.
Optional. On Stack Management → Stack Config page,
configure the role of switch A as Master, the role of switch B,
C, D as Member in Role Config section.
4
Configure the Auto
Copy Software
function.
Optional. On Stack Management → Auto Copy Software
page, enable Auto Copy Software function.
Connect the switches:
Connect switch A, B, C and D as the network diagram shows, and then power the switches on
to establish a stack.
Return to CONTENTS
52
Chapter 6 Switching
Switching module is used to configure the basic functions of the switch, including four
submenus: Port, LAG, Traffic Monitor and MAC Address.
6.1 Port
The Port function, allowing you to configure the basic features for the port, is implemented on
the Port Config, Port Mirror, Port Security, Protected Ports and Loopback Detection pages.
6.1.1 Port Config
On this page, you can configure port status, speed mode, duplex mode, flow control and jumbo
frames for ports.
Choose the menu Switching→Port→Port Config to load the following page.
Figure 6-1 Port Config
Configuration Procedure:
Select and configure your desired ports or LAGs. Then click Apply to make the settings
effective.
Entry Description:
UNIT:
Click 1 to configure physical ports. Click LAGS
to configure
LAGs.
Type:
Displays the port type. Copper
indicates an Ethernet port,
and Sfp indicates a fiber port.
53
Description:
Give a port description for identification.
Status:
With this option enabled, the port forwards packets normally.
Otherwise, the port discards all the receive
d packets. By
default, it is enabled.
Speed:
Select the appropriate speed mode for the port. When
Auto
is selected, the port autonegotiates speed mode with the
connected device. The default setting is Auto
. This value is
recommended if both ends of the li
ne support
autonegotiation.
Duplex:
Select the appropriate duplex mode for the port. There are
three options: Half, Full and Auto
. When Auto is selected, the
port autonegotiates duplex mode with the connected device.
The default setting is Auto.
Flow Con
trol:
With this option enabled, the switch synchronizes the data
transmission speed with the peer device, thus avoiding the
packet loss caused by congestion. By default, it is disabled.
Jumbo
With this option properly configured, the port can send jumbo
f
rames. The default MTU (Maximum Transmission Unit) size
for frames received and sent on all ports is 1518 bytes. You
can specify the MTU size up to 13312
bytes, thus allowing the
port to send jumbo frames.
LAG:
Displays the LAG which the port belongs to.
Note:
1. The switch cannot be managed through the disabled port. Please enable the port which is
used to manage the switch.
2. The parameters of the port members in a LAG should be set as the same.
3. We recommend that you set the ports on both ends of a link as the same speed and
duplex mode.
6.1.2 Port Mirror
This function allows the switch to forward packet copies of the monitored ports to a specific
monitoring port. Then you can analyze the copied packets to monitor network traffic and
troubleshoot network problems.
54
Choose the menu Switching→Port→Port Mirror to load the following page.
Figure 6-2 Mirror Session List
The above page displays a mirror session, and no more session can be created. Click Edit to
configure the mirror session on the following page.
55
Figure 6-3 Port Mirror Config
Configuration Procedure:
1) In the Destination Port section, specify a monitoring port for the mirror session, and click
Apply.
2) In the Source Port section, select one or multiple monitored ports for configuration. The
set the parameters and click Apply to make the settings effective.
Entry Description:
Session:
Displays session number.
Destination Port:
Input or select a physical port fro
m the port panel as the
mirroring port.
Ingress:
With this option enabled, the packets received by the monitored
port will be copied to the monitoring port. By default, it is
disabled.
Egress:
With this option enabled, the packets sent by the monitored p
ort
will be copied to the monitoring port. By default, it is disabled.
56
LAG:
Displays the LAG number which the port belongs to.
Note:
1. The member port of a LAG cannot be set as a monitoring port or monitored port.
2. A port cannot be set as the monitoring port and monitored port at the same time.
6.1.3 Port Security
You can use this feature to limit the number of MAC addresses that can be learned on each
port, thus preventing the MAC address table from being exhausted by the attack packets.
Choose the menu Switching→Port→Port Security to load the following page.
Figure 6-4 Port Security
Configuration Procedure:
1) Select one or multiple ports for security configuration.
2) Specify the maximum number of the MAC addresses that can be learned on the port, and
then select the learn mode of the MAC addresses.
3) Select the status of the port security feature.
4) Click Apply to make the settings effective.
57
Entry Description:
Max Learned MAC:
Specify the maximum number of MAC addresses that can be
learned on the port. When the learned MAC address number
reaches the limit, the port will stop learning.
Learned Num:
Displays the number of MAC addresses that have been
learned on the port.
Learn Mode:
Select the Learn Mode for the port.
• Dynamic: The switch will delete the MAC addresses that
are not used or updated within the aging time. It is the
default setting.
• Static:
The learned MAC addresses are out of the
influence of the aging time and can only be deleted
manually. The learned entries will be cleared after the
switch is rebooted.
Status:
Enable or disable the port security feature on the port. By
default, it is disabled.
Note:
1. Port Security cannot be enabled on the member port of a LAG, and the port with Port
Security enabled cannot be added to a LAG.
2. On one port, Port Security and 802.1X cannot be enabled at the same time.ort Security
function is disabled when the 802.1X function is enabled.
6.1.4 Protected Ports
This feature is used to restrict the communication between the specific ports. A port that is a
member of a protected ports group is a protected port. Protected ports in the same protected
ports group cannot forward traffic to each other, even if they are in the same VLAN. But the
protected ports can forward traffic to the unprotected ports and the ports that are in a different
group.
Choose the menu Switching→Port→Port Isolation to load the following page.
Figure 6-5 Port Isolation Config
The above page displays the information of protected ports groups. Click Edit to configure the
group on the following page.
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Configuration Procedure:
Select and configure your desired ports or LAGs. Then click Apply to make the settings
effective.
Entry Description:
Group:
Displays the ID of the group for configuration.
Group Name:
Give a group name for identification.
Protected Ports: Select member ports in this group.
Protected ports in the same group cannot forward traffic to
each other, even if they are in the same VLAN. But the protected
por
ts can forward traffic to the unprotected ports and the ports
that are in a different group.
6.1.5 Loopback Detection
Loopback Detection allows the switch to detect loops in the network. When a loop is detected
on a port, the switch will display an alert on the management interface and further block the
corresponding port according to your configurations.
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Choose the menu Switching → Port → Loopback Detection to load the following page.
Figure 6-6 Loopback Detection Config
Configuration Procedure:
1) In the Global Config section, enable loopback detection and configure the global
parameters. Then click Apply to make the settings effective.
2) In the Port Config section, select one or multiple ports for configuration. Then set the
parameters and click Apply to make the settings effective.
3) View the loopback detection information on this page.
Entry Description:
Global Config
LoopbackDetection
Status:
Enable loopback detection globally.
Detection Interval: Set the interval of sending loopback detection packets.
The value ranges from 1 to 1000 seconds and the default value
is 30 seconds.
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Automatic
Recovery Time:
Set the recovery time globally, after which the blocked port in
Auto Recovery mode can automatically recover to normal
status.
It should be integral times of detection interval. The value
ranges from 1-100 and is 3 by default
Web Refresh
Status:
With this option enabled, the switch refreshes the web timely. By
default, it is disabled.
Web Refresh
Interval:
If you enabled web refresh, set the refresh interval between 3
and 100 seconds. The default value is 6 seconds.
Port Config
Status:
Enable loopback detection for the port.
Operation Mode:
Select the operation mode when a loopback is detected on the
port:
Alert: The switch will display alerts. It is the default setting.
Port based:
In addition to displaying alerts, the switch will
block the port on which the loop is detected.
Recovery Mode: If you select Port Based
as the operation mode, you also need
to configure the recovery mode for the blocked port:
Auto:
The blocked port will automatically recover to normal
status after the autom
atic recovery time. It is the default
setting.
Manual:
You need to manually release the blocked port.
Click the Recovery button to release the selected port.
Loop Status:
Displays whether a loop is detected on the port.
Block Status:
Displays whether the port is blocked.
LAG:
Displays the LAG number the port belongs to.
Note:
1. Recovery Mode is not selectable when Alert is chosen in Operation Mode.
2. To avoid broadcast storm, we recommend that you enable storm control before loopback
detection is enabled.
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6.1.6 Default Settings
Feature Default Settings
Port Config Type: Copper
Status: Enable
Speed: Auto
Duplex: Auto
Flow Control: Disable
Jumbo: 1518
Port Mirror Ingress: Disable
Egress: Disable
Port Security Max Learned MAC: 1024
Learned Num: 0
Learned Mode: Dynamic
Status: Disable
Loopback Detection Loopback Detection Status: Disable
Detection Interval: 30 seconds
Automatic Recovery Time: 3 detection times
Web Refresh Status: Disable
Web Refresh Interval: 6 seconds
Port Status: Disable
Operation mode: Alert
Recovery mode: Auto
6.2 LAG
With the LAG (Link Aggregation Group) function, you can aggregate multiple physical ports into
a logical interface to increase link bandwidth and configure the backup ports to enhance the
connection reliability. You can configure LAG in two ways:
• Static LAG: The member ports are manually added to the LAG.
• LACP (Link Aggregation Control Protocol): The switch uses LACP to implement dynamic
link aggregation and disaggregation by exchanging LACP packets with its partner. LACP
extends the flexibility of the LAG configuration.
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For the functions like IGMP Snooping, 802.1Q VLAN, MAC VLAN, Protocol VLAN, VLAN-VPN,
GVRP, Voice VLAN, STP, QoS, DHCP Snooping and Flow-Control, the member pot of a LAG
follows the configuration of the LAG but not its own. The configurations of the port can take
effect only after it leaves the LAG.
The port which is enabled with Port Security, Port Mirror, MAC Address Filtering or 802.1X
cannot be added to LAG, and the member port of a LAG cannot be enabled with these
functions.
The configuration guidelines are as follows:
• Ensure that both ends of the aggregation link work in the same LAG mode. For example, if
the local end works in LACP mode, the peer end should be set as LACP mode.
• Ensure that devices on both ends of the aggregation link use the same number of physical
ports with the same speed, duplex, jumbo and flow control mode.
• A port cannot be added to more than one LAG at the same time.
• LACP does not support half-duplex links.
• One static LAG supports up to eight member ports. All the member ports share the traffic
evenly. If an active link fails, the other active links share the traffic evenly.
• One LACP LAG supports more than eight member ports, but at most eight of them can be
active. Using LACP protocol, the switches negotiate parameters and determine the active
ports. When an active link fails, the link with the highest priority among the inactive links will
replace the faulty link and start to forward data.
• LAG (Link Aggregation Group) is to combine a number of ports together to make a single
high-bandwidth data path, so as to implement the traffic load sharing among the member
ports in the group and to enhance the connection reliability.
Tips:
1. Calculate the bandwidth for a LAG: If a LAG consists of the four ports in the speed of
1000Mbps Full Duplex, the whole bandwidth of the LAG is up to 8000Mbps (2000Mbps * 4)
because the bandwidth of each member port is 2000Mbps counting the up-linked speed
of 1000Mbps and the down-linked speed of 1000Mbps.
2. The traffic load of the LAG will be balanced among the ports according to the Aggregate
Arithmetic. If the connections of one or several ports are broken, the traffic of these ports
will be transmitted on the normal ports, so as to guarantee the connection reliability.
6.2.1 LAG Table
On this page, you can view the information of the current LAG of the switch and configure the
Load-balancing Algorithm.
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Choose the menu Switching→LAG→LAG Table to load the following page.
Figure 6-7 LAG Table
Configuration Procedure:
In the Global Config section, select the load-balancing algorithm. Click Apply to make the
settings effective.
In LAG Table, view the information of the current LAG.
Entry Description:
Hash Algorithm:
Select the Hash Algorithm, based on which the switch
can choose the port to send the received packets. In
this way, different data flows are forwarded on different
physical links to implement load balancing. There are six
options:
• SRC MAC: The computation is based on the source
MAC addresses of the packets.
• DST MAC
: The computation is based on the
destination MAC addresses of the packets.
• SRC MAC+DST MAC: The computation is based on
the source and destination MAC addresses of the
packets.
• SRC IP: The computation is based on the source IP
addresses of the packets.
• DST IP: The computation is based on the
destination IP addresses of the packets.
• SRC IP+DST IP: The computation is based on the
source and destination IP addresses of the packets.
LAG Table
Select:
Select the desired LAG. It is multi-optional.
Group Number:
Displays the LAG number.
Description:
Displays the description of LAG.
Member:
Displays the LAG member.
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Ope
ration: Click Edit to modify the settings of the LAG.
Click Detail to get the detailed information of the LAG.
Click the Detail button for the detailed information of your selected LAG.
Figure 6-8 Detail Information
6.2.2 Static LAG
On this page, you can manually configure the LAG. The LACP feature is disabled for the
member ports of the manually added Static LAG.
Choose the menu Switching→LAG→Static LAG to load the following page.
Figure 6-9 Static LAG Config
Configuration Procedure:
Select and configure your desired ports or LAGs. Then click Apply.
Entry Description:
Group Number:
Select a Group Number for the LAG.
Description:
Displays the description of the LAG for identification.
65
Member Port
UNIT:
Select the unit ID of the desired member in the stack.
Member Port:
Select the port as the LAG member. Clearing all the ports
of the LAG will delete this LAG.
Tips:
1. Load-balancing algorithm is effective only for outgoing traffic. If the data stream is not well
shared by each link, you can change the algorithm of the outgoing interface.
2. Please properly choose the load-balancing algorithm to avoid data stream transferring
only on one physical link. For example, if the destination device of the packets is a server
with the fixed MAC address and IP address, you can set the algorithm as “SRC MAC+SRC
IP” to allow the switch to determine the forwarding port based on the source MAC
addresses and source IP addresses of the received packets.
6.2.3 LACP Config
On this page, you can configure the LACP feature of the switch.
Choose the menu Switching→LAG→LACP Config to load the following page.
Figure 6-10 LACP Config
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Configuration Procedure:
1) In the LAG Config section, select a LAG for configuration.
2) In the Member Port section, select the member ports for the LAG. It is multi-optional.
3) Click Apply.
Entry Description:
System Priority:
Specify the system priority for the switch. A smaller value means a
higher priority.
To keep active ports consistent at both ends, you can set the
priority of one device to
be higher than that of the other device.
The device with higher priority will determine its active ports, and
the other device can select its active ports according to the
selection result of the device with higher priority. If the two ends
have the same s
ystem priority value, the end with a smaller MAC
address has the higher priority.
Admin Key:
Specify the Admin Key which you can regard as the group number
of the LAG.
Note that the group number of other static LAGs cannot be set as
an Admin Key. The valid value ranges from 1 to 64.
Port Priority:
Specify the Port Priority. A smaller value means a higher port
priority.
The port with higher priority in an LAG will be selected as the
active port to forward data. If two ports have the same priority
value, the port with a smaller port number has the higher priority.
Mode:
Select the LACP mode for the port.
In LACP, the switch uses LACPDU (Link Aggregation Control
Protocol Data Unit) to negotiate the parameters with the peer end.
In this way, the two ends sele
ct active ports and form the
aggregation link. The LACP mode determines whether the port
will take the initiative to send the LACPDU. There are two modes:
Passive
: The port will not send LACPDU before receiving the
LACPDU from the peer end.
Active: The port will take the initiative to send LACPDU.
Status:
Enable the LACP function of the port. By default, it is disabled.
LAG:
Displays the LAG number which the port belongs to.
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6.2.4 Default Settings
Feature Default Settings
Global Config Hash Algorithm: SRC MAC + DST MAC
LACP System Priority: 32768
Admin Key: 0
Port Priority: 0
Mode: Passive
Status: Disable
6.3 Traffic Monitor
The Traffic Monitor function, monitoring the traffic of each port, is implemented on the Traffic
Summary and Traffic Statistics pages.
6.3.1 Traffic Summary
Traffic Summary screen displays the traffic information of each port, which facilitates you to
monitor the traffic and analyze the network abnormity.
Choose the menu Switching→Traffic Monitor→Traffic Summary to load the following page.
Figure 6-11 Traffic Summary
Configuration Procedure:
1) To get the real-time traffic summary, enable auto refresh in the Auto Refresh section, or
click Refresh at the bottom of the page.
2) In the Traffic Summary section, click 1 to show the information of the physical ports, and
click LAGS to show the information of the LAGs.
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Entry Description:
Auto Refresh
Auto Refresh:
With this potion enabled, the switch refreshes the web timely.
Refresh Rate:
Specify the refresh interval in seconds.
Traffic Summary
Port:
Displays the port number.
Packets Rx:
Displays the number of packets received on the port. Error
packets are not counted in.
Packets Tx:
Displays the number of packets transmitted on the port.
Octets Rx:
Displ
ays the number of octets received on the port. Error octets
are counted in.
Octets Tx:
Displays the number of octets transmitted on the port.
Statistics:
Click the Statistics
button to view the detailed traffic statistics of
the port.
6.3.2 Traffic Statistics
Traffic Statistics screen displays the detailed traffic information of each port, which facilitates
you to monitor the traffic and locate faults promptly.
69
Choose the menu Switching→Traffic Monitor→Traffic Statistics to load the following page.
Figure 6-12 Traffic Statistics
Configuration Procedure:
1) To get the real-time traffic summary, enable auto refresh in the Auto Refresh section, or
click Refresh at the bottom of the page.
2) In the Traffic Summary section, click 1 to show the information of the physical ports, and
click LAGS to show the information of the LAGs.
Entry Description:
Auto Refresh
Auto Refresh:
Allows you to Enable/Disable refreshing the Traffic Summary
automatically.
Refresh Rate:
Enter a value in seconds to specify the refresh interval.
Statistics
Received:
Displays the details of the packets received on the port.
Sent:
Displays the details of the packets transmitted on the port.
Broadcast:
Displays the number of good broadcast packets
received or
sent on the port. Error frames are not counted in.
Multicast:
Displays the number of good multicast packets received or
sent on the port. Error frames are not counted in.
70
Unicast:
Displays the number of good unicast packets received or
sent on the port. Error frames are not counted in.
Jumbo
Displays the number of jumbo frames received or sent on the
port.
Alignment Errors:
Displays the number of the received packets that have a bad
Frame Check Sequence (FCS) with a non-
integral octet
(Align
ment Error) and have a bad FCS with an integral octet
(CRC Error). The length of the packet is between 64 bytes
and 1518 bytes.
UndersizePkts:
Displays the number of the received packets (excluding error
packets) that are less than 64 bytes long.
Pkts64O
ctets:
Displays the number of the received packets (including error
packets) that are 64 bytes long.
Pkts65to127Octets:
Displays the number of the received packets (including error
packets) that are between 65 and 127 bytes long.
Pkts128to255Octets:
Disp
lays the number of the received packets (including error
packets) that are between 128 and 255 bytes long.
Pkts256to511Octets:
Displays the number of the received packets (including error
packets) that are between 256 and 511 bytes long.
Pkts512to1023Oct
ets:
Displays the number of the received packets (including error
packets) that are between 512 and 1023 bytes long.
PktsOver1023Octets:
Displays the number of the received packets (including error
packets) that are more than 1023 bytes long.
Collisions:
Displays the number of collisions experienced by a port
during packet transmissions.
6.4 MAC Address
The main function of the switch is forwarding the packets to the correct ports based on the
destination MAC address of the packets. Address Table contains the port-based MAC address
information, which is the base for the switch to forward packets quickly. The entries in the
Address Table can be updated by auto-learning or configured manually. Most entries are
generated and updated by auto-learning. In the stable networks, the static MAC address
entries can facilitate the switch to reduce broadcast packets and enhance the efficiency of
packets forwarding remarkably. The address filtering feature allows the switch to filter the
undesired packets and forbid its forwarding so as to improve the network security.
71
The types and the features of the MAC Address Table are listed as the following:
Type Configuration
Way
Aging
out
Being kept after reboot
(if the configuration is
saved)
Relationship between the
bound MAC address and
the port
Static
Address
Table
Manually
configuring No Yes
The bound MAC address
cannot be learned by the
other ports in the same
VLAN.
Dynamic
Address
Table
Automatically
learning Yes No
The bound MAC address
can be learned by the
other ports in the same
VLAN.
Filtering
Address
Table
Manually
configuring No Yes -
Table 6-1 Types and features of Address Table
This function includes four submenus: Address Table, Static Address, Dynamic Address and
Filtering Address.
6.4.1 Address Table
On this page, you can view all the information of the Address Table.
72
Choose the menu Switching→MAC Address→Address Table to load the following page.
Figure 6-13 Address Table
The following entries are displayed on this screen:
Search Option
MAC Address:
Enter the MAC address of your desired entry.
VLAN ID:
Enter the VLAN ID of your desired entry.
Port:
Select the corresponding port number or link-
aggregation number
of your desired entry.
Type:
Select the type of your desired entry.
All:
This option allows the address table to display all the
address entries.
Static:
This option allows the address table to display the
static address entries only.
Dynamic: This option allows the a
ddress table to display the
dynamic address entries only.
Filtering:
This option allows the address table to display the
filtering address entries only.
UNIT:
Select the unit ID of the desired member in the stack.
73
Address Table
UNIT:
Select the unit ID of the desired member in the stack.
MAC Address:
Displays the MAC address learned by the switch.
VLAN ID:
Displays the corresponding VLAN ID of the MAC address.
Port:
Displays the corresponding port number or link-
aggregation
number of the MAC address.
Type:
Displays the Type of the MAC address.
Aging Status:
Displays the Aging status of the MAC address.
6.4.2 Static Address
The static address table maintains the static address entries which can be added or removed
manually, independent of the aging time. In the stable networks, the static MAC address entries
can facilitate the switch to reduce broadcast packets and remarkably enhance the efficiency of
packets forwarding without learning the address. The static MAC address learned by the port
with Port Security enabled in the static learning mode will be displayed in the Static Address
Table.
Choose the menu Switching→MAC Address→Static Address to load the following page.
Figure 6-14 Static Address
The following entries are displayed on this screen:
Create Static Address
MAC Address:
Enter the static MAC Address to be bound.
74
VLAN ID:
Enter the corresponding VLAN ID of the MAC address.
UNIT:
Select the unit ID of the desired member in the stack.
Port:
Select a port to be bound.
Search Option
Search Option:
Select a Search Option from the pull-
down list and click the
Search
button to find your desired entry in the Static Address
Table.
• All:
This option allows the Static Address Table to display all
the static address entries.
• MAC: Enter the MAC address of your desired entry.
• VLAN ID: Enter the VLAN ID number of your desired entry.
•
Port: Enter the Port number of your desired entry.
Static Address Table
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the entry to delete or modify the corresponding port
number. It is multi-optional.
MAC Address:
Displays the static MAC Address.
VLAN ID:
Displays the corresponding VLAN ID of the MAC address.
Port:
Displays the corresponding Port num
ber of the MAC address. Here
you can modify the port number to which the MAC address is
bound. The new port should be in the same VLAN.
Type:
Displays the Type of the MAC address.
Aging Status:
Displays the Aging Status of the MAC address.
Note:
1. If the corresponding port number of the MAC address is not correct, or the connected port
(or the device) has been changed, the switch cannot forward the packets correctly. Please
reset the static address entry appropriately.
2. If the MAC address of a device has been added to the Static Address Table, connecting
the device to another port will cause its address not to be recognized dynamically by the
switch. Therefore, please ensure the entries in the Static Address Table are correct and
valid.
3. The MAC address in the Static Address Table cannot be added to the Filtering Address
Table or bound to a port dynamically.
75
6.4.3 Dynamic Address
The dynamic address can be generated by the auto-learning mechanism of the switch. The
Dynamic Address Table can update automatically by auto-learning or the MAC address aging
out mechanism.
To fully utilize the MAC address table, which has a limited capacity, the switch adopts an aging
mechanism for updating the table. That is, the switch removes the MAC address entries related
to a network device if no packet is received from the device within the aging time.
On this page, you can configure the dynamic MAC address entry.
Choose the menu Switching→MAC Address→Dynamic Address to load the following page.
Figure 6-15 Dynamic Address
The following entries are displayed on this screen:
Aging Config
Auto Aging:
Allows you to Enable/Disable the Auto Aging feature.
Aging Time:
Enter the Aging Time for the dynamic address.
76
Search Option
Search Option:
Select a Search Option from the pull-down list and click the
Search
button to find your desired entry in the Dynamic Address Table.
• All: This option allows the Dynamic
Address Table to display all
the dynamic address entries.
• MAC: Enter the MAC address of your desired entry.
• VLAN ID: Enter the VLAN ID number of your desired entry.
• Port: Enter the Port number or link-aggregation number
of your
desired entry.
Dynamic Address Table
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the entry to delete the dynamic address or to bind the MAC
address to the corresponding port statically. It is multi-optional.
MAC Address:
Displays the dynamic MAC Address.
VLAN ID:
Displays the corresponding VLAN ID of the MAC address.
Port:
Displays the corresponding port number or link-
aggregation
number of the MAC address.
Type:
Displays the Type of the MAC address.
Aging Status:
Displays the Aging Status of the MAC address.
Bind:
Click the Bind
button to bind the MAC address of your selected
entry to the corresponding port statically.
Tips:
Setting aging time properly helps implement effective MAC address aging. The aging time that
is too long or too short results in a decrease of the switch performance. If the aging time is too
long, excessive invalid MAC address entries maintained by the switch may fill up the MAC
address table. This prevents the MAC address table from updating with network changes in
time. If the aging time is too short, the switch may remove valid MAC address entries. This
decreases the forwarding performance of the switch. It is recommended to keep the default
value.
6.4.4 Filtering Address
The filtering address is to forbid the undesired packets to be forwarded. The filtering address
can be added or removed manually, independent of the aging time. The filtering MAC address
allows the switch to filter the packets which includes this MAC address as the source address
or destination address, so as to guarantee the network security. The filtering MAC address
entries act on all the ports in the corresponding VLAN.
77
Choose the menu Switching→MAC Address→Filtering Address to load the following page.
Figure 6-16 Filtering Address
The following entries are displayed on this screen:
Create Filtering Address
MAC Address:
Enter the MAC Address to be filtered.
VLAN ID:
Enter the corresponding VLAN ID of the MAC address.
Search Option
Search O
ption: Select a Search Option from the pull-down list and click the
Search
button to find your desired entry in the Filtering Address Table.
• All: This option allows the Filtering
Address Table to display all
the filtering address entries.
• MAC Address: Enter the MAC address of your desired entry.
•
VLAN ID: Enter the VLAN ID number of your desired entry.
Filtering Address Table
Select:
Select the entry to delete the corresponding filtering address. It is
multi-optional.
MAC Address:
Displays the filtering MAC Address.
VLAN ID:
Displays the corresponding VLAN ID.
Type:
Displays the Type of the MAC address.
Aging Status:
Displays the Aging Status of the MAC address.
Note:
1. The MAC address in the Filtering Address Table cannot be added to the Static Address
Table or bound to a port dynamically.
2. This MAC address filtering function is not available if the 802.1X feature is enabled.
Return to CONTENTS
78
Chapter 7 VLAN
The traditional Ethernet is a data network communication technology basing on CSMA/CD
(Carrier Sense Multiple Access/Collision Detect) via shared communication medium. Through
the traditional Ethernet, the overfull hosts in LAN will result in serious collision, flooding
broadcasts, poor performance or even breakdown of the Internet. Though connecting the
LANs through switches can avoid the serious collision, the flooding broadcasts cannot be
prevented, which will occupy plenty of bandwidth resources, causing potential serious security
problems.
A Virtual Local Area Network (VLAN) is a network topology configured according to a logical
scheme rather than the physical layout. The VLAN technology is developed for switches to
control broadcast in LANs. By creating VLANs in a physical LAN, you can divide the LAN into
multiple logical LANs, each of which has a broadcast domain of its own. Hosts in the same
VLAN communicate with one another as if they are in a LAN. However, hosts in different VLANs
cannot communicate with one another directly. Therefore, broadcast packets are limited in a
VLAN. Hosts in the same VLAN communicate with one another via Ethernet whereas hosts in
different VLANs communicate with one another through the Internet devices such as Router,
the Layer3 switch, etc. The following figure illustrates a VLAN implementation.
Figure 7-1 VLAN implementation
Compared with the traditional Ethernet, VLAN enjoys the following advantages.
1. Broadcasts are confined to VLANs. This decreases bandwidth utilization and improves
network performance.
2. Network security is improved. VLANs cannot communicate with one another directly.
That is, a host in a VLAN cannot access resources in another VLAN directly, unless
routers or Layer 3 switches are used.
3. Network configuration workload for the host is reduced. VLAN can be used to group
specific hosts. When the physical position of a host changes within the range of the
VLAN, you need not to change its network configuration.
79
A VLAN can span across multiple switches, or even routers. This enables hosts in a VLAN to be
dispersed in a looser way. That is, hosts in a VLAN can belong to different physical network
segment. This switch supports three ways, namely, 802.1Q VLAN, MAC VLAN and Protocol
VLAN, to classify VLANs. VLAN tags in the packets are necessary for the switch to identify
packets of different VLANs. The switch can analyze the received untagged packets on the port
and match the packets with the MAC VLAN, Protocol VLAN and 802.1Q VLAN in turn. If a
packet is matched, the switch will add a corresponding VLAN tag to it and forward it in the
corresponding VLAN.
7.1 802.1Q VLAN
VLAN tags in the packets are necessary for the switch to identify packets of different VLANs.
The switch works at the data link layer in OSI model and it can identify the data link layer
encapsulation of the packet only, so you can add the VLAN tag field into the data link layer
encapsulation for identification.
In 1999, IEEE issues the IEEE 802.1Q protocol to standardize VLAN implementation, defining
the structure of VLAN-tagged packets. IEEE 802.1Q protocol defines that a 4-byte VLAN tag is
encapsulated after the destination MAC address and source MAC address to show the
information about VLAN.
As shown in the following figure, a VLAN tag contains four fields, including TPID (Tag Protocol
Identifier), Priority, CFI (Canonical Format Indicator), and VLAN ID.
Figure 7-2 Format of VLAN Tag
1. TPID: TPID is a 16-bit field, indicating that this data frame is VLAN-tagged. By default, it
is 0x8100.
2. Priority: Priority is a 3-bit field, referring to 802.1p priority. Refer to section “QoS & QoS
profile” for details.
3. CFI: CFI is a 1-bit field, indicating whether the MAC address is encapsulated in the
standard format in different transmission media. This field is not described in detail in
this chapter.
4. VLAN ID: VLAN ID is a 12-bit field, indicating the ID of the VLAN to which this packet
belongs. It is in the range of 0 to 4,095. Generally, 0 and 4,095 is not used, so the field is
in the range of 1 to 4,094.
VLAN ID identifies the VLAN to which a packet belongs. When the switch receives an
un-VLAN-tagged packet, it will encapsulate a VLAN tag with the default VLAN ID of the inbound
port for the packet, and the packet will be assigned to the default VLAN of the inbound port for
transmission.
In this User Guide, the tagged packet refers to the packet with VLAN tag whereas the untagged
packet refers to the packet without VLAN tag, and the priority-tagged packet refers to the
packet with VLAN tag whose VLAN ID is 0.
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Link Types of ports
When creating the 802.1Q VLAN, you should set the link type for the port according to its
connected device. The link types of port including the following three types:
1. ACCESS: The ACCESS port can be added in a single VLAN, and the egress rule of the
port is UNTAG. The PVID is same as the current VLAN ID. If the ACCESS port is added to
another VLAN, it will be removed from the current VLAN automatically.
2. TRUNK: The TRUNK port can be added in multiple VLANs. The egress rule of the port is
UNTAG if the arriving packet’s VLAN tag is the same as the port’s PVID, otherwise the
egress rule is TAG. The TRUNK port is generally used to connect the cascaded network
devices for it can receive and forward the packets of multiple VLANs.
3. GENERAL: The GENERAL port can be added in multiple VLANs and set various egress
rules according to the different VLANs. The default egress rule is UNTAG. The PVID can
be set as the VID number of any valid VLAN.
PVID
PVID (Port VLAN ID) is the default VID of the port. When the switch receives an
un-VLAN-tagged packet, it will add a VLAN tag to the packet according to the PVID of its
received port and forward the packets.
When creating VLANs, the PVID of each port, indicating the default VLAN to which the port
belongs, is an important parameter with the following two purposes:
1. When the switch receives an un-VLAN-tagged packet, it will add a VLAN tag to the
packet according to the PVID of its received port
2. PVID determines the default broadcast domain of the port, i.e. when the port receives
UL packets or broadcast packets, the port will broadcast the packets in its default
VLAN.
Different packets, tagged or untagged, will be processed in different ways, after being received
by ports of different link types, which is illustrated in the following table.
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Port Type
Receiving Packets
Forwarding Packets
Untagged Packets
Tagged Packets
Access
When untagged
packets are
received, the port
will add the default
VLAN tag, i.e. the
PVID of the ingress
port, to the packets.
If the VID of packet is the
same as the PVID of the port,
the packet will be received.
If the VID of packet is not the
same as the PVID of the port,
the packet will be dropped.
The packet will be forwarded
after removing its VLAN tag.
Trunk
If the VID of packet is allowed
by the port, the packet will be
received.
If the VID of packet is
forbidden by the port, the
packet will be dropped.
If the arriving packet’s VLAN
tag is the same as the port’s
PVID, the packet will be
forwarded after remo
ving its
VLAN tag, otherwise the
packet will be forwarded
with its current VLAN tag.
General
If the egress rule of port is
TAG, the packet will be
forwarded with its current
VLAN tag.
If the egress rule of port is
UNTAG, the packet will be
forwarded
after removing its
VLAN tag.
Table 7-1 Relationship between Port Types and VLAN Packets Processing
IEEE 802.1Q VLAN function is implemented on the VLAN Config and Port Config pages.
7.1.1 VLAN Config
On this page, you can view the current created 802.1Q VLAN.
Choose the menu VLAN→802.1Q VLAN→VLAN Config to load the following page.
Figure 7-3 VLAN Table
To ensure the normal communication of the factory switch, the default VLAN of all ports is set
to VLAN1.
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The following entries are displayed on this screen:
VLAN Table
Select
：
Select the desired entry to delete the corresponding VLAN. It is
multi-optional.
VLAN ID：
Displays the ID number of VLAN.
Name：
Displays the user-defined name of VLAN.
Members：
Displays the port members in the VLAN.
Operation
：
Allows you to view or modify the information for each entry.
• Edit: Click to modify the settings of VLAN.
•
Detail: Click to get the information of VLAN.
Click Edit button to modify the settings of the corresponding VLAN. Click Create button to
create a new VLAN.
Figure 7-4 Create or Modify 802.1Q VLAN
The following entries are displayed on this screen:
VLAN Info
VLAN ID:
Enter the ID number of VLAN.
Name:
Displays the user-defined name of VLAN.
Untagged port: Displays the untagged port which is ACCESS, TRUNK
or
GENERAL.
UNIT:
Select the unit ID of the desired member in the stack.
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Tagged port:
Displays the tagged port which is TRUNK or GENERAL.
7.1.2 Port Config
Before creating the 802.1Q VLAN, please acquaint yourself with all the devices connected to
the switch in order to configure the ports properly.
Choose the menu VLAN→802.1Q VLAN→Port Config to load the following page.
Figure 7-5 802.1Q VLAN – Port Config
The following entries are displayed on this screen:
VLAN Port Config
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired port for configuration. It is multi-optional.
Port:
Displays the port number.
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Link Type: Select the Link Type from the pull-down list for the port.
• ACCESS:
The ACCESS port can be added in a single VLAN,
and the egress rule of the port is UNTAG. The PVID is same
as the current VLAN ID. If the current VLAN is deleted, the
PVID will be set to 1 by default.
• TRUNK: The TRUNK port can be added in multiple VLANs.
The egress rule of the port is UNTAG if the arriving packet’s
VLAN tag is the same as the port’s PVID, otherwise the
egress rule is TAG.
The PVID can be set as the VID number
of any valid VLAN.
• GENERAL:
The GENERAL port can be added in multiple
VLANs and set various egress rules according to the
different VLANs. The default egress rule is UNTAG. The
PVID can be set as the VID number of any valid VLAN.
PVID:
Enter the PVID number of the port.
LAG:
Displays the LAG to which the port belongs.
VLAN: Click the Detail
button to view the information of the VLAN to
which the port belongs.
Click the Detail button to view the information of the corresponding VLAN.
Figure 7-6 View the Current VLAN of Port
The following entries are displayed on this screen:
VLAN of Port
VLAN ID
：
Displays the ID number of VLAN.
VLAN Name:
Displays the user-defined description of VLAN.
Operation:
Allows you to remove the port from the current VLAN.
Configuration Procedure:
Step
Operation
Description
1
Set the link type for
port.
Required. On the VLAN→802.1Q VLAN→Port Config page, set
the link type for the port basing on its connected device.
2
Create VLAN. Required. On the VLAN→802.1Q VLAN→VLAN Config page,
click the Create button to create a VLAN. Enter the VLAN ID
and the description for the V
LAN. Meanwhile, specify its
member ports.
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Step
Operation
Description
3
Modify/View VLAN. Optional. On the VLAN→802.1Q VLAN→VLAN Config page,
click the Edit/Detail
button to modify/view the information of
the corresponding VLAN.
4
Delete VLAN Optional. On the VLAN→802.1Q VLAN→VLAN Config page,
select the desired entry to delete the corresponding VLAN by
clicking the Delete button.
7.2 Application Example for 802.1Q VLAN
Network Requirements
Switch A is connecting to PC A and Server B;
Switch B is connecting to PC B and Server A;
PC A and Server A is in the same VLAN;
PC B and Server B is in the same VLAN;
PCs in the two VLANs cannot communicate with each other.
Network Diagram
Configuration Procedure
Configure switch A
Step
Operation
Description
1
Configure the
Link Type of the
ports
Required. On VLAN→802.1Q VLAN→Port Config page, configure
the link type of Port 2, Port 3 and Port 4 as ACCESS, TRUNK and
ACCESS respectively.
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Step
Operation
Description
2
Create VLAN10 Required. On VLAN→802.1Q VLAN→VLAN Config page, create a
VLAN with its VLAN ID as 10, owning Port 2 and Port 3.
3
Create VLAN20 Required. On VLAN→802.1Q VLAN→VLAN Config page, create a
VLAN with its VLAN ID as 20, owning Port 3 and Port 4.
Configure switch B
Step
Operation
Description
1
Configure the
Link Type of the
ports
Required. On VLAN→802.1Q VLAN→Port Config page, configure
the link type of Port 7, Port 6 and Port 8 as ACCESS, TRUNK and
ACCESS respectively.
2
Create VLAN10 Required. On VLAN→802.1Q VLAN→VLAN Config page, create a
VLAN with its VLAN ID as 10, owning Port 6 and Port 8.
3
Create VLAN20 Required. On VLAN→802.1Q VLAN→VLAN Config page, create a
VLAN with its VLAN ID as 20, owning Port 6 and Port 7.
7.3 MAC VLAN
MAC VLAN technology is the way to classify VLANs according to the MAC addresses of Hosts.
A MAC address corresponds to a single VLAN ID. For the device in a MAC VLAN, if its MAC
address is bound to VLAN, the device can be connected to another member port in this VLAN
and still takes its member role effect without changing the configuration of VLAN members.
The packet in MAC VLAN is processed in the following way:
1. When receiving an untagged packet, the switch matches the packet with the current MAC
VLAN. If the packet is matched, the switch will add a corresponding MAC VLAN tag to it. If
no MAC VLAN is matched, the switch will add a tag to the packet according to the PVID of
the received port. Thus, the packet is assigned automatically to the corresponding VLAN
for transmission.
2. When receiving tagged packet, the switch will process it basing on the 802.1Q VLAN. If the
received port is the member of the VLAN to which the tagged packet belongs, the packet
will be forwarded normally. Otherwise, the packet will be discarded.
3. If the MAC address of a Host is classified into 802.1Q VLAN, please set its connected port
of switch to be a member of this 802.1Q VLAN so as to ensure the packets forwarded
normally.
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Choose the menu VLAN→MAC VLAN to load the following page.
Figure 7-7 Create and View MAC VLAN
Configuration Procedure:
Specify a MAC address and a VLAN ID. Then click Create to make the settings effective.
Entry Description:
MAC Address:
Enter the MAC address.
VLAN ID: Enter the ID number of the MAC VLAN. This VLAN should be one
of the 802.1Q VLANs the ingress port belongs to.
7.4 Application Example for MAC VLAN
Network Requirements
Switch A and switch B are connected to meeting room A and meeting room B respectively,
and the two rooms are for all departments;
Notebook A and Notebook B, special for meeting room, are of two different departments;
The two departments are in VLAN10 and VLAN20 respectively. The two notebooks can
just access the server of their own departments, that is, Server A and Server B, in the two
meeting rooms;
The MAC address of Notebook A is 00-19-56-8A-4C-71, Notebook B’s MAC address is
00-19-56-82-3B-70.
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Network Diagram
Configuration Procedure
Configure switch A
Step
Operation
Description
1
Configure the
Link Type of the
ports
Required. On VLAN→802.1Q VLAN→Port Config page, configure the
link type of Port 11 and Port 12 as GENERAL and TRUNK
respectively.
2
Create VLAN10 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 11 and Port 12, and
configure the egress rule of Port 11 as Untag.
3
Create VLAN20 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 20, owning Port 11 and Port 12, and
configure the egress rule of Port 11 as Untag.
4
Configure MAC
VLAN 10
On VLAN→MAC VLAN→MAC VLAN page, create MAC VLAN10 with
the MAC address as 00-19-56-8A-4C-71.
5
Configure MAC
VLAN 20
On VLAN→MAC VLAN→MAC VLAN page, create MAC VLAN10 with
the MAC address as 00-19-56-82-3B-70.
Configure switch B
Step
Operation
Description
1
C
onfigure the
Link Type of the
ports
Required. On VLAN→802.1Q VLAN→Port Config page, configure the
link type of Port 21 and Port 22 as GENERAL and TRUNK
respectively.
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Step
Operation
Description
2
Create VLAN10 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VL
AN ID as 10, owning Port 21 and Port 22, and
configure the egress rule of Port 21 as Untag.
3
Create VLAN20 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 20, owning Port 21 and Port 22, and
configure the egress rule of Port 21 as Untag.
4
Configure MAC
VLAN 10
On VLAN→MAC VLAN→MAC VLAN page, create MAC VLAN10 with
the MAC address as 00-19-56-8A-4C-71.
5
Configure MAC
VLAN 20
On VLAN→MAC VLAN→MAC VLAN page, create MAC VLAN10 with
the MAC address as 00-19-56-82-3B-70.
Configure switch C
Step
Operation
Description
1
Configure the
Link Type of the
ports
Required. On VLAN→802.1Q VLAN→Port Config page, configure the
link type of Port 2 and Port 3 as GENERAL, and configure the link type
of Port 4 and Port 5 as ACCESS.
2
Create VLAN10 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 2, Port 3 and Port 5,
3
Create VLAN20 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 20, owning Port 2, Port 3 and Port 4,
7.5 Protocol VLAN
Protocol VLAN is another way to classify VLANs basing on network protocol. Protocol VLANs
can be sorted by IP, IPX, DECnet, AppleTalk, Banyan and so on. Through the Protocol VLANs,
the broadcast domain can span over multiple switches and the Host can change its physical
position in the network with its VLAN member role always effective. By creating Protocol
VLANs, the network administrator can manage the network clients basing on their actual
applications and services effectively.
This switch can classify VLANs basing on the common protocol types listed in the following
table. Please create the Protocol VLAN to your actual need.
Protocol Type
Type value
ARP
0x0806
IP
0x0800
MPLS
0x8847/0x8848
IPX
0x8137
IS-IS
0x8000
LACP
0x8809
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Protocol Type
Type value
802.1X
0x888E
Table 7-2 Protocol types in common use
The packet in Protocol VLAN is processed in the following way:
1. When receiving an untagged packet, the switch matches the packet with the current
Protocol VLAN. If the packet is matched, the switch will add a corresponding Protocol
VLAN tag to it. If no Protocol VLAN is matched, the switch will add a tag to the packet
according to the PVID of the received port. Thus, the packet is assigned automatically to
the corresponding VLAN for transmission.
2. When receiving tagged packet, the switch will process it basing on the 802.1Q VLAN. If the
received port is the member of the VLAN to which the tagged packet belongs, the packet
will be forwarded normally. Otherwise, the packet will be discarded.
3. If the Protocol VLAN is created, please set its enabled port to be the member of
corresponding 802.1Q VLAN so as to ensure the packets forwarded normally.
7.5.1 Protocol Group Table
On this page, you can create Protocol VLAN and view the information of the current defined
Protocol VLANs.
Choose the menu VLAN→Protocol VLAN→Protocol Group Table to load the following page.
Figure 7-8 Protocol Group Table
Entry Description:
Select:
Select the desired entry. It is multi-optional.
Template Id
Displays the template ID of the protocol group.
Protocol Name:
Displays the protocol of the protocol group.
VLAN ID:
Displays the corresponding VLAN ID of the protocol.
Member:
Displays the member of the protocol group.
Operate:
Click the Edit button to modify the settings of the entry.
7.5.2 Protocol Group
On this page, you can configure the Protocol Group.
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Choose the menu VLAN→Protocol VLAN→Protocol Group to load the following page.
Figure 7-9 Configure Protocol Group
Configuration Procedure:
1) Specify a Template ID and a VLAN ID.
2) Add your desired ports into this protocol group.
3) Click Apply to make the settings effective.
Entry Description:
Template Id:
Specify a template ID for this group.
VLAN ID:
Enter the ID number of the Protocol VLAN. This VLAN should be
one of the 802.1Q VLANs the ingress port belongs to.
7.5.3 Protocol Template
The Protocol Template should be created before configuring the Protocol VLAN. You can add
your desired Protocol Template on this page.
Choose the menu VLAN→Protocol VLAN→Protocol Template to load the following page.
Figure 7-10 Create and View Protocol Template
Configuration Procedure:
1) Specify a template ID and a name for the protocol template.
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2) Enter the ethernet type filed of your desired protocol.
3) Click Create to make the settings effective.
Entry Description:
Template Id:
Give a template ID for the protocol template.
Protocol Name:
Give a name for the protocol template.
Ether Type:
Enter the Ethernet protocol type field in the protocol template.
Note:
The Protocol Template bound to VLAN cannot be deleted.
7.6 Application Example for Protocol VLAN
Network Requirements
Department A is connected to the company LAN via Port12 of switch A;
Department A has IP host and AppleTalk host;
IP host, in VLAN10, is served by IP server while AppleTalk host is served by AppleTalk
server;
Switch B is connected to IP server and AppleTalk server.
Network Diagram
93
Configuration Procedure
Configure switch A
Step
Operation
Description
1
Configure the
Link Type of the
ports
Required. On VLAN→802.1Q VLAN→Port Config page, configure the
link type of Port 11 and Port 13 as ACCESS, and configure the link
type of Port 12 as GENERAL.
2
Create VLAN10 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Por
t 12 and Port 13, and
configure the egress rule of Port 12 as Tagged.
3
Create VLAN20 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 20, owning Port 11 and Port 12, and
configure the egress rule of Port 12 as Tagged.
Configure switch B
Step
Operation
Description
1
Configure the
Link Type of the
ports
Required. On VLAN→802.1Q VLAN→Port Config page, configure the
link type of Port 4 and Port 5 as ACCESS, and configure the link type
of Port 3 as GENERAL.
2
Create VLAN10 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 3 and Port 4, and configure
the egress rule of Port 3 as Tagged.
3
Create VLAN20 Required. On VLAN→802.1Q VLAN→VLAN Config
page, create a
VLAN with its VLAN ID as 20, owning Port 3 and Port 5, and configure
the egress rule of Port 3 as Tagged.
4
Create Protocol
Template
Required. On VLAN→Protocol VLAN→Protocol Template page,
configure the protocol templates practically. The Ether Type of IP
network packets is 0800 and that of AppleTalk network packets is
809B.
5
Create Protocol
VLAN10
On VLAN→Protocol VLAN→Protocol Group page, create protocol
VLAN 10 with Protocol as IP. Select and enable Port 3, Port 4 and
Port 5 for Protocol VLAN feature.
6
Create Protocol
VLAN20
On VLAN→Protocol VLAN→Protocol Group page, create protocol
VLAN 20 with Protocol as AppleTalk. Select and enable Port 3, Port 4
and Port 5 for Protocol VLAN feature.
7.7 VLAN VPN
With the increasing application of the Internet, the VPN (Virtual Private Network) technology is
developed and used to establish the private network through the operators’ backbone
networks. VLAN-VPN (Virtual Private Network) function, the implement of a simple and flexible
Layer 2 VPN technology, allows the packets with VLAN tags of private networks to be
encapsulated with VLAN tags of public networks at the network access terminal of the Internet
94
Service Provider. And these packets will be transmitted with double-tag across the public
networks.
The VLAN-VPN function provides you with the following benefits:
1. Provides simple Layer 2 VPN solutions for small-sized LANs or intranets.
2. Saves public network VLAN ID resource.
3. You can have VLAN IDs of your own, which is independent of public network VLAN IDs.
4. When the network of the Internet Service Provider is upgraded, the user’s network with a
relative independence can still work normally without changing the current configurations.
In addition, the switch supports the feature to adjust the TPID Values of VLAN VPN Packets.
TPID (Tag Protocol Identifier) is a field of the VLAN tag. IEEE 802.1Q specifies the value of TPID
to be 0x8100. This switch adopts the default value of TPID (0x8100) defined by the protocol.
Other manufacturers use other TPID values (such as 0x9100 or 0x9200) in the outer tags of
VLAN-VPN packets. To be compatible with devices coming from other manufacturers, this
switch can adjust the TPID values of VLAN-VPN packets globally. You can configure TPID
values by yourself. When a port receives a packet, this port will replace the TPID value in the
outer VLAN tag of this packet with the user-defined value and then send the packet again. Thus,
the VLAN-VPN packets sent to the public network can be recognized by devices of other
manufacturers.
The position of the TPID field in an Ethernet packet is the same as the position of the protocol
type field in the packet without VLAN Tag. Thus, to avoid confusion happening when the switch
forwards or receives a packet, you must not configure the following protocol type values listed
in the following table as the TPID value.
Protocol type
Value
ARP
0x0806
IP
0x0800
MPLS
0x8847/0x8848
IPX
0x8137
IS-IS
0x8000
LACP
0x8809
802.1X
0x888E
Table 7-3 Values of Ethernet frame protocol type in common use
This VLAN VPN function is implemented on the VPN Config, VLAN Mapping and Port Enable
pages.
7.7.1 VLAN-VPN Config
On this page, you can configure the VLAN-VPN feature.
95
Choose the menu VLAN→VLAN VPN→VPN Config to load the following page.
Figure 7-11 VPN Global Config
Configuration Procedure:
1) In the Global Config section, configure the global TPID according to your need.
2) In the VPN Up-Link Ports section, select your desired ports as the VPN up-link ports.
3) Click Apply to make the settings effectivce.
Entry Description:
Global TPID:
Enter the global TPID (Tag Protocol Identifier). The default
setting is 8100.
VPN Up-link ports:
Select the desired port as the VPN Up-link port.
7.7.2 Default Settings
Feature Default Settings
Global TPID 8100
7.8 GVRP
GVRP (GARP VLAN Registration Protocol) is an implementation of GARP (generic attribute
registration protocol). GVRP allows the switch to automatically add or remove the VLANs via
the dynamic VLAN registration information and propagate the local VLAN registration
information to other switches, without having to individually configure each VLAN.
GARP
GARP provides the mechanism to assist the switch members in LAN to deliver, propagate and
register the information among the members. GARP itself does not work as the entity among
the devices. The application complied with GARP is called GARP implementation, and GVRP is
the implementation of GARP. When GARP is implemented on a port of device, the port is called
GARP entity.
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The information exchange between GARP entities is completed by messages. GARP defines
the messages into three types: Join, Leave and LeaveAll.
• Join Message: When a GARP entity expects other switches to register certain attribute
information of its own, it sends out a Join message. And when receiving the Join message
from the other entity or configuring some attributes statically, the device also sends out a
Join message in order to be registered by the other GARP entities.
• Leave Message: When a GARP entity expects other switches to deregister certain attribute
information of its own, it sends out a Leave message. And when receiving the Leave
message from the other entity or deregistering some attributes statically, the device also
sends out a Leave message.
• LeaveAll Message: Once a GARP entity starts up, it starts the LeaveAll timer. After the timer
times out, the GARP entity sends out a LeaveAll message. LeaveAll message is to
deregister all the attribute information so as to enable the other GARP entities to re-register
attribute information of their own.
Through message exchange, all the attribute information to be registered can be propagated
to all the switches in the same switched network.
The interval of GARP messages is controlled by timers. GARP defines the following timers:
• Hold Timer: When a GARP entity receives a piece of registration information, it does not
send out a Join message immediately. Instead, to save the bandwidth resources, it starts
the Hold timer, puts all registration information it receives before the timer times out into
one Join message and sends out the message after the timer times out.
• Join Timer: To transmit the Join messages reliably to other entities, a GARP entity sends
each Join message two times. The Join timer is used to define the interval between the two
sending operations of each Join message.
• Leave Timer: When a GARP entity expects to deregister a piece of attribute information, it
sends out a Leave message. Any GARP entity receiving this message starts its Leave timer,
and deregisters the attribute information if it does not receives a Join message again
before the timer times out.
• LeaveAll Timer: Once a GARP entity starts up, it starts the LeaveAll timer, and sends out a
LeaveAll message after the timer times out, so that other GARP entities can re-register all
the attribute information on this entity. After that, the entity restarts the LeaveAll timer to
begin a new cycle.
GVRP
GVRP, as an implementation of GARP, maintains dynamic VLAN registration information and
propagates the information to other switches by adopting the same mechanism of GARP.
After the GVRP feature is enabled on a switch, the switch receives the VLAN registration
information from other switches to dynamically update the local VLAN registration information,
including VLAN members, ports through which the VLAN members can be reached, and so on.
The switch also propagates the local VLAN registration information to other switches so that all
the switching devices in the same switched network can have the same VLAN information. The
VLAN registration information includes not only the static registration information configured
locally, but also the dynamic registration information, which is received from other switches.
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7.8.1 GVRP Config
On this page, you can configure the GVRP feature.
Choose the menu VLAN→GVRP→GVRP Config to load the following page.
Figure 7-12 GVRP Config
Configuration Procedure:
Specify a MAC address and a VLAN ID. Then click Create to make the settings effective.
1) Globally enable the GVRP feautre.
2) Configure the parameters for ports.
3) Click Apply to make the settings effective.
Entry Description:
Global Config
GVRP:
Enable the GVRP function. By default, it is disabled.
Port Config
Select:
Select the desired port for configuration. It is multi-optional.
Port:
Displays the port number.
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Status:
Enable/Disable the GVRP feature for the port. The port type
should be set to TRUNK before enabling the GVRP feature.
LeaveAll Timer:
Once the LeaveAll Timer is set, the port with GVRP enabled can
send
a LeaveAll message after the timer times out, so that other
GARP ports can re-register all the attribute information. After that,
the LeaveAll timer will start to begin a new cycle. T
he LeaveAll
Timer ranges from 200 to 6000 centiseconds.
Join Timer:
To
guarantee the transmission of the Join messages, a GARP port
sends each Join message two times. The Join Timer is used to
define the interval between the two sending operations of each
Join message. The Join Timer ranges from 10 to 100
centiseconds.
Leave
Timer: Once the Leave Timer is set, the GARP port receiving a Leave
message will start its Leave timer, and deregister the attribute
information if it does not receive a Join message again before the
timer times out. The Leave Timer ranges from 20 to 600
centiseconds.
LAG:
Displays the LAG to which the port belongs.
Note:
LeaveAll Timer >= 10* Leave Timer, Leave Timer >= 2*Join Timer.
7.8.2 Default Settings
Feature Default Settings
Global GVRP: Disable
Port Conifg Status: Disable
LeaveAll Timer (centisecond): 1000
Join Timer (centisecond): 20
Leave Timer (centisecond): 60
7.9 Private VLAN
Private VLANs, designed to save VLAN resources of uplink devices and decrease broadcast,
are sets of VLAN pairs that share a common primary identifier. To guarantee user information
security, the ease with which to manage and account traffic for service providers, in campus
network, service providers usually require that each individual user is Layer-2 separated. VLAN
feature can solve this problem. However, as stipulated by IEEE 802.1Q protocol, a device can
only support up to 4094 VLANs. If a service provider assigns one VLAN per user, the VLANs will
be far from enough; as a result, the number of users this service provider can support is limited.
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Private VLAN adopts Layer 2 VLAN structure. A Private VLAN consists of a Primary VLAN and a
Secondary VLAN, providing a mechanism for achieving layer-2-separation between ports. For
uplink devices, all the packets received from the downstream are without VLAN tags. Uplink
devices need to identify Primary VLANs but not Secondary VLANs. Therefore, they can save
VLAN resources without considering the VLAN configuration in the lower layer. Meanwhile, the
service provider can assign each user an individual Secondary VLAN, so that users are
separated at the Layer 2 level.
Private VLAN technology is mainly used in campus or enterprise networks to achieve user
Layer-2-separation and to save VLAN resources of uplink devices.
The Elements of a Private VLAN
Promiscuous port: A promiscuous port connects to and communicates with the uplink device.
The PVID of the promiscuous port is the same with the Primary VLAN ID. One promiscuous port
can only join to one Primary VLAN.
Host port: A host port connects to and communicates with terminal device. The PVID of the
host port is the same as the Secondary VLAN ID. One host port can only belong to one Private
VLAN.
Primary VLAN: A Private VLAN has one Primary VLAN and one Secondary VLAN. Primary VLAN
is the user VLAN uplink device can identify, but it is not the actual VLAN the end user is in. Every
port in a private VLAN is a member of the primary VLAN. The primary VLAN carries
unidirectional traffic downstream from the promiscuous ports to the host ports and to other
promiscuous ports.
Secondary VLAN: Secondary VLAN is the actual VLAN the end user is in. Secondary VLANs
are associated with a primary VLAN, and are used to carry traffic from hosts to uplink devices.
There are two types of secondary VLANS:
Isolated VLAN－Members in an isolated VLAN are isolated with each other. Each isolated
VLAN must bind to a primary VLAN.
Community VLAN－Members in a community VLAN can communicate with each other
directly. Each community VLAN must bind to a primary VLAN.
Features of Private VLAN
1. A Private VLAN contains one Primary VLAN and one Secondary VLAN.
2. A VLAN cannot be set as the Primary VLAN and Secondary VLAN simultaneously.
3. A Secondary VLAN can only join one private VLAN.
4. A Primary VLAN can be associated with multi-Secondary VLANs to create
multi-Private VLANs.
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Private VLAN Implementation
To hide Secondary VLANs from uplink devices and save VLAN resources, Private VLAN
containing one Primary VLAN and one Secondary VLAN requires the following characteristics:
Packets from different Secondary VLANs can be forwarded to the uplink device via
promiscuous port and carry no corresponding Secondary VLAN information.
Packets from Primary VLANs can be sent to end users via host port and carry no Primary
VLAN information.
Private VLAN functions are implemented on the PVLAN Config and Port Config pages.
7.9.1 PVLAN Config
On this page, you can create Private VLAN and view the information of the current defined
Private VLANs.
Choose the menu VLAN→Private VLAN→PVLAN Config to load the following page.
Figure 7-13 Create Private VLAN
The following entries are displayed on this screen:
Create Private VLAN
Primary VLAN:
Enter the ID number of the Primary VLAN.
Secondary VLAN:
Enter the ID number of the Secondary VLAN.
Search Option
Search Option:
Select a Search Option from the pull-down list and click the Search
button to find your desired entry in Private VLAN.
All: Enter the Primary VLAN ID number or Secondary VLAN ID
of the desired Private VLAN.
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Primary VLAN ID: Enter the Primary VLAN ID number of the
desired Private VLAN.
Secondary VLAN ID: Enter the Secondary VLAN ID number of
the desired Private VLAN.
Private VLAN Table
Select:
Select the entry to delete. It is multi-optional.
Primary VLAN:
Displays the Primary VLAN ID number of the Private VLAN.
Secondary VLAN:
Displays the Secondary VLAN ID number of the Private VLAN.
Port:
Displays the Port number of the Private VLAN.
7.9.2 Port Config
The Private VLAN provides two Port Types for the ports, Promiscuous and Host. Usually, the
Promiscuous port is used to connect to uplink devices while the Host port is used to connect
to the terminal hosts, such as PC and Server.
Choose the menu VLAN→Private VLAN→Port Config to load the following page.
Figure 7-14 Create and View Protocol Template
The following entries are displayed on this screen:
Port Config
Port selected:
Select the desired port for
configuration. You can input one or
select from the port table down the blank.
Port Type:
Select the Port Type from the pull-down list for the port.
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Primary VLAN:
Specify the Primary VLAN the port belongs to.
Secondary VLAN:
Specify the Secondary VLAN the port belongs to.
UNIT:
Select the unit ID of the desired member in the stack.
Private VLAN Port Table
UNIT:
Select the unit ID of the desired member in the stack.
Port ID:
Displays the port number.
Port Type:
Displays the corresponding Port Type.
Note:
1. A Host Port can only join to one Private VLAN.
2. A Promiscuous Port can only join to one Primary VLAN.
3. If you want to add a Promiscuous port to different Private VLANs with the same Primary
VLAN, you need to add the Promiscuous port to any one of these Private VLANs.
Configuration Procedure:
Step
Operation
Description
1
Create Private VLAN. Required. On the VLAN→Private VLAN→P
VLAN Config
page, e
nter the Primary VLAN and Secondary VLAN,
select one type of secondary VLAN and then click the
Create button.
2
Add ports to Private VLAN Required. On the VLAN→Private VLAN→Port Config
page, select the desired ports and co
nfigure the port
types and click the Apply button.
3
Delete VLAN. Optional. On the VLAN→Private VLAN→PVLAN Config
page, select the desired entry to delete the
corresponding VLAN by clicking the Delete button.
7.10 Application Example for Private VLAN
Network Requirements
Switch C is connecting to switch A, switch A is connecting to switch B;
Switch A is connecting to VLAN4 and VLAN5;
Switch B is connecting to VLAN5 and VLAN8;
For switch C, packets from switch A and switch B have no VLAN tags. Switch C needs not to
consider the VLANs of switch A and switch B;
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Network Diagram
Configuration Procedure
Configure Switch C
Step
Operation
Description
1
Create VLAN6 Required. On VLAN→802.1Q VLAN→VLAN Config page, create a
VLAN with its VLAN ID as 6, owning Port 1/0/1.
Configure switch A
Step
Operation
Description
1
Create Private
VLANs.
Required. On the VLAN→Private VLAN→PVLAN Config page,
Enter the Primary VLAN 6 and Secondary VLAN 4-
5, select one
type of secondary VLAN and then click the Create button.
2
Add
Promiscuous
port to Private
VLANs
Required. On the VLAN→Private VLAN→Port Config page,
configure the port type of Port 1/0/2 and Port 1/0/4 as
Promiscuous, enter Primary VLAN 6 and Secondary VLAN 4, and
click the Apply button.
3
Add Host port
to Private
VLANs
Required. On the VLAN→Private VLAN→Port Config page,
configure the port type of Port 1/0/10 as Host, enter Primary VLAN
6 and Secondary VLAN 4, and click the Apply button. Configure the
port type of Port 1/0/11 as Host
, enter Primary VLAN 6 and
Secondary VLAN 5, and click the Apply button
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Configure switch B
Step
Operation
Description
1
Create Private
VLANs.
Required. On the VLAN→Private VLAN→PVLAN Config page,
enter the Primary VLAN 6 and Secondary VLAN 5 and 8, select one
type of secondary VLAN and then click the Create button.
2
Add
Promiscuous
port to Private
VLANs
Required. On the VLAN→Private VLAN→Port Config page,
configure the port type of Port 1/0/3 as Promiscuous, enter
Primary VLAN 6 and Secondary VLAN 5, and click the Apply button.
3
Add Host port
to Private
VLANs
Required. On the VLAN→Private VLAN→Port Config page,
configure the port type of 1/0/12 as Host, enter Primary VLAN 6
and Secondary VLAN 5, and click the Apply button. Configure the
port type of Port 1/0/13 as Host
, enter Primary VLAN 6 and
Secondary VLAN 8, and click the Apply button.
Return to CONTENTS
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Chapter 8 Spanning Tree
STP (Spanning Tree Protocol), subject to IEEE 802.1D standard, is to disbranch a ring network in
the Data Link layer in a local network. Devices running STP discover loops in the network and
block ports by exchanging information, in that way, a ring network can be disbranched to form a
tree-topological ring-free network to prevent packets from being duplicated and forwarded
endlessly in the network.
BPDU (Bridge Protocol Data Unit) is the protocol data that STP and RSTP use. Enough
information is carried in BPDU to ensure the spanning tree generation. STP is to determine the
topology of the network via transferring BPDUs between devices.
To implement spanning tree function, the switches in the network transfer BPDUs between
each other to exchange information and all the switches supporting STP receive and process
the received BPDUs. BPDUs carry the information that is needed for switches to figure out the
spanning tree.
STP Elements
Bridge ID (Bridge Identifier): The value of the priority and MAC address of the switch. It is used
to select the root bridge. The bridge ID is composed of a 2-byte priority and a 6-byte MAC
address. The priority is allowed to be configured manually on the switch, and the switch with
the lowest priority value will be elected as the root bridge. If the priority of all the switches are
the same, the switch with the lowest MAC address is selected as the root bridge.
Root Bridge: The root of a spanning tree. There is only one root bridge in each spanning tree,
and the root bridge has the lowest bridge ID. Configure the switch with the best performance in
the ring network as the root bridge to ensure best network performance and reliability.
Designated Bridge: Indicates the switch has the lowest path cost from the switch to the root
bridge in each LAN segment. BPDUs are forwarded to the network segment through the
designated bridge.
Path Cost: The path cost reflects the link speed of the port. The smaller the value, the higher
link speed the port has.
The path cost can be manually configured on each port. If not, the path cost value is
automatically calculated according to the link speed as shown below:
Link Speed
Path Cost Value
10Mb/s
2,000,000
100Mb/s
200,000
1Gb/s
2,0000
10Gb/s
2000
Table 8-1 Default path cost value
Root Path Cost: The root path cost is the accumulated path costs from the root bridge to the
other switches. When the root bridge sends its BPDU, the root path cost value is 0. When a
connected switch receives this BPDU, it increments the path cost of its local incoming port.
Then it forwards this BPDU to the downstream switch, with the updated root path cost. The
value of the accumulated root path cost increases as the BPDU propagates further.
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Root Port: The port selected on non-root bridges to provide the lowest root path cost. There is
only one root port in each non-root bridge.
Designated Port: The port selected for each LAN segment to provide the lowest root path cost
from that LAN segment to the root bridge.
Port Priority: The port priority can be set to an integral multiple of 16 in the range of 0~240.
The lower value priority has the higher priority. The port with the higher priority has more
chance to be chosen as the root port.
The following network diagram shows the sketch map of spanning tree. Switch A, B and C are
connected together in order. After STP generation, switch A is chosen as the root bridge, the
path from port 2 to port 6 is blocked.
Bridge: Switch A is the root bridge in the whole network; switch B is the designated bridge of
switch C.
Port: Port 3 is the root port of switch B and port 5 is the root port of switch C; port 1 and 2
are the designated ports of switch A and port 4 is the designated port of switch B; port 6 is
the blocked port of switch C.
Figure 8-1 Basic STP diagram
STP Timers
Hello Time:
Hello Time is 2 seconds. It specifies the interval to send BPDU packets. It is used to test the
links.
Max Age:
Max Age ranges from 6 to 40 seconds. It specifies the maximum time the switch can wait
without receiving a BPDU before attempting to reconfigure.
Forward Delay:
Forward Delay ranges from 4 to 30 seconds. It specifies the time for the port to transit its state
after the network topology is changed.
When the STP regeneration caused by network malfunction occurs, the STP structure will get
some corresponding change. However, as the new configuration BPDUs cannot be spread in
the whole network at once, the temporal loop will occur if the port transits its state immediately.
Therefore, STP adopts a state transit mechanism, that is, the new root port and the designated
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port begins to forward data after twice forward delay, which ensures the new configuration
BPDUs are spread in the whole network.
BPDU Comparing Principle in STP mode
Assuming two BPDUs: BPDU X and BPDU Y
If the root bridge ID of X is smaller than that of Y, X is superior to Y.
If the root bridge ID of X equals that of Y, but the root path cost of X is smaller than that of Y, X
is superior to Y.
If the root bridge ID and the root path cost of X equal those of Y, but the bridge ID of X is
smaller than that of Y, X is superior to Y.
If the root bridge ID, the root path cost and bridge ID of X equal those of Y, but the port ID of X
is smaller than that of Y, X is superior to Y.
STP Generation
In the beginning
In the beginning, each switch regards itself as the root, and generates a configuration BPDU for
each port on it as a root, with the root path cost being 0, the ID of the designated bridge being
that of the switch, and the designated port being itself.
Comparing BPDUs
Each switch sends out configuration BPDUs and receives a configuration BPDU on one of its
ports from another switch. The following table shows the comparing operations.
Step
Operation
1 If the priority of the BPDU received on the port is lower than that of the BPDU of
the port itself, the switch discards the BPDU and does not change the BPDU of
the port itself. If the priority of the BPDU is hig
her than that of the BPDU of the
port itself, the switch replaces the BPDU of the port with the received one.
2
The switch compares the BPDUs of all the ports, and selects the BPDU with the
highest priority as the switch’s BPDU.
Table 8-2 Comparing BPDUs
Selecting the root bridge
The root bridge is selected by BPDU comparing. The switch with the smallest bridge ID is
chosen as the root bridge.
Selecting the root port
The non-root switch will go through the following steps when selecting a root port:
1) Choose the port that provides the lowest root path cost as the root port.
2) If multiple ports provide the same root path cost, the port which is connected to the
neighboring switch (the switch will go through to reach the root bridge) with the smallest
bridge ID will be selected as the root port.
3) If multiple ports go through the same neighboring switch, the port with the highest priority
will be selected as the root port.
4) If the priorities are the same between the ports, the port with the smallest port number will
be selected as the root port.
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Selecting the designated bridge and designated port
Here are the steps taken by switches in selecting the designated bridge and designated port
for each LAN segment:
1) Choose the switch with the lowest root path cost from the LAN segment to the root bridge
as the designated bridge. The port through which the designated bridge is attached to the
LAN segment is the designated port.
2) If multiple switches have the same root path cost, the one with the smallest bridge ID will
be chosen as the designated bridge. The port through which the designated bridge is
attached to the LAN segment is the designated port.
3) If it happens that there are more than one port through which the designated bridge is
attached to the LAN segment, the port with the highest priority will be selected as the
designated port.
4) If the priorities of the ports on the same designated bridge are still the same, the port with
the smallest port number will be selected as the designated port.
Tips
：
In a stable STP topology, only the root port and designated port can forward data, and the
other ports are blocked. The blocked ports only can receive BPDUs.
RSTP (Rapid Spanning Tree Protocol), evolved from the 802.1D STP standard, enable Ethernet
ports to transit their states rapidly.
The alternate port can rapidly transit to the new root port once the old root port failed.
The backup port can rapidly transit to the new designated port once the old designated
port failed.
The condition for the designated port to transit its port state rapidly: The designated
port is an edge port or connecting to a point-to-point link. If the designated port is an
edge port, it can directly transit to forwarding state; if the designated port is connecting
to a point-to-point link, it can transit to forwarding state after getting response from the
downstream switch through handshake.
RSTP Elements
Edge Port: Indicates the port connected directly to terminals.
P2P Link: Indicates the link between two switches directly connected.
MSTP (Multiple Spanning Tree Protocol), compatible with both STP and RSTP and subject to
IEEE 802.1s standard, not only enables spanning trees to converge rapidly, but also enables
packets of different VLANs to be forwarded along their respective paths so as to provide
redundant links with a better load-balancing mechanism.
Features of MSTP:
MSTP combines VLANs and spanning tree together via VLAN-Instance mapping table. It
binds several VLANs to an instance to save communication cost and network
resources.
MSTP divides a spanning tree network into several regions. Each region has several
internal spanning trees, which are independent of each other.
MSTP provides a load-balancing mechanism for the packets transmission in the VLAN.
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MSTP is compatible with both STP and RSTP.
MSTP Elements
MST Region (Multiple Spanning Tree Region): An MST region consists of multiple
interconnected switches. These switches have the same region name, the same revision level
and the same VLAN-Instance mapping table.
MSTI (Multiple Spanning Tree Instance): The MST instance is a spanning tree running in the
MST region. Multiple MST instances can be established in one MST region and they are
independent of each other. Each spanning tree is referred to as a multiple spanning tree
instance.
VLAN-Instance Mapping: VLAN-Instance Mapping describes the mapping relationship
between VLANs and instances. Multiple VLANs can be mapped to a same instance, but one
VLAN can be mapped to only one instance.
IST (Internal Spanning Tree): A special MST instance with an instance ID of 0. By default, all the
VLANs are mapped to IST.
CST (Common Spanning Tree): A CST is the spanning tree in a switched network that connects
all MST regions in the network.
CIST (Common and Internal Spanning Tree): A CIST, comprising IST and CST, is the spanning
tree in a switched network that connects all switches in the network.
The following figure shows the network diagram in MSTP.
Figure 8-2 Basic MSTP diagram
MSTP
MSTP divides a network into several MST regions. The CST is generated between these MST
regions, and multiple spanning trees can be generated in each MST region. Each spanning
trees is called an instance. As well as STP, MSTP uses BPDUs to generate spanning tree. The
only difference is that the BPDU for MSTP carries the MSTP configuration information on the
switches.
Port States
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In an MSTP, ports can be in the following four states:
Forwarding: In this status the port can receive/forward data, receive/send BPDU packets
as well as learn MAC address.
Learning: In this status the port can receive/send BPDU packets and learn MAC address.
Blocking: In this status the port can only receive BPDU packets.
Disconnected: In this status the port is not participating in the STP.
Port Roles
In an MSTP, the following roles exist:
Root Port: The port selected on non-root bridges to provide the lowest root path cost.
There is only one root port in each non-root bridge.
Designated Port: The port selected for each LAN segment to provide the lowest root path
cost from that LAN segment to the root bridge
Master Port: Indicates the port that connects a MST region to the common root. The path
from the master port to the common root is the shortest path between this MST region
and the common root.
Alternate Port: If a port is not selected as the designated port for it receives better BPDUs
from another switch, it will become an alternate port.
In RSTP/MSTP, the alternate port is the backup for the root port. It is blocked when the root
port works normally. Once the root port fails, the alternate port will become the new root
port.
In STP, the alternate port is always blocked.
Backup Port: If a port is not selected as the designated port for it receives better BPDUs
from the switch it belongs to, it will become a backup port.
In RSTP/MSTP, the designated port is the backup for the designated port. It is blocked
when the designated port works normally. Once the root port fails, the backup port will
become the new designated port.
In STP, the backup port is always blocked.
Disabled: Indicates the port that is not participating in the STP.
The following diagram shows the different port roles.
Figure 8-3 Port roles
The Spanning Tree module is mainly for spanning tree configuration of the switch, including
four submenus: STP Config, Port Config, MSTP Instance and STP Security.
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8.1 STP Config
The STP Config function, for global configuration of spanning trees on the switch, can be
implemented on STP Config and STP Summary pages.
8.1.1 STP Config
Before configuring spanning trees, you should make clear the roles each switch plays in each
spanning tree instance. Only one switch can be the root bridge in each spanning tree. On this
page you can globally configure the spanning tree function and related parameters.
Choose the menu Spanning Tree→STP Config→STP Config to load the following page.
Figure 8-4 STP Config
Configuration Procedure:
1) Enable spanning tree function, select the STP mode, and click Apply.
2) Configure the related parameters and click Apply.
Entry Description:
Global Config
Spanning Tree:
Enable or disable STP function globally on the switch.
Mode: Select the desired STP mode on the switch.
STP:
Specify the spanning tree mode as STP (Spanning Tree
Protocol).
RSTP: Specify the spanning tree mode as RSTP (Rapid Spanning
Tree Protocol).
MSTP: Specify the spanning tree mode as MSTP (Multiple
Spanning Tree Protocol).
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Parameters Config
CIST Priority: Specify the CIST priority of the switch. The valid values are from 0 to
61440, which are divisible by 4096.By default, it is 32768. The switch
with the lower value has the higher priority.
CIST priority is usually a parameter configured in MSTP, which
means the priority of a switch in CIST. The switch with the highest
priority will be elected as the root bridge in CIST.
In STP/RSTP, CIST priority means the priority of a switch in the
spanning tree. The switch with the highest priority is elected as the
root bridge.
Hello Time
Hello Time is 2 seconds, it’s the interval to send BPDUs.
Max Age: Specify the maximum time the switch can wait without receiving a
BPDU before attempting to regenerate a spanning tree. The valid
values are from 6 to 40 in seconds, and the default value is 20.
Forward Delay: Specify the time for the port to transit its
state after the network
topology is changed. The valid values are from 4 to 30 in seconds,
and the default value is 15.
TxHoldCount: Specify the maximum BPDU transmission rate of a port. The valid
values are from 1 to 20, and the default value is 5.
Max Hops: Specify the maximum number of hops that occur in a specific region
before the BPDU is discarded. The valid values are from 1 to 40, and
the default value is 20.
Max Hops is a parameter configured in MSTP. You need not
configure it if the spanning tree mode is STP/RSTP.
Note:
1. To prevent frequent network flapping, make sure that Hello Time, Forward Delay, and Max
Age conform to the formulas: 2*(Hello Time + 1) <= Max Age, 2*(Forward Delay - 1) >= Max
Age.
2. The forward delay parameter and the network diameter are correlated. A too small forward
delay parameter may result in temporary loops. A too large forward delay may cause a
network unable to resume the normal state in time. The default value is recommended.
3. A too small max age parameter may result in the switches regenerating spanning trees
frequently and cause network congestions to be falsely regarded as link problems. A too
large max age parameter result in the switches unable to find the link problems in time,
which in turn handicaps spanning trees being regenerated in time and makes the network
less adaptive. The default value is recommended.
4. If the TxHold Count parameter is too large, the number of MSTP packets being sent in each
hello time may be increased with occupying too much network resources. The default
value is recommended.
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8.1.2 STP Summary
On this page you can view the related parameters for Spanning Tree function.
Choose the menu Spanning Tree→STP Config→STP Summary to load the following page.
Figure 8-5 STP Summary
8.2 Port Config
On this page you can configure the parameters of the ports for CIST.
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Choose the menu Spanning Tree→Port Config→Port Config to load the following page.
Figure 8-6 Port Config
Configuration Procedure:
Configure the parameters of the ports for CIST.
Entry Description:
Port Config
UNIT:
Select the desired unit or LAGs.
Select:
Select the desired port for STP configuration. It is multi-optional.
Port:
Displays the port number of the switch.
Status:
Enable or disable spanning tree function on the desired port.
Priority: Enter the value of port priority from 0 to 240 divisible by 16, and the
default value is 128.
The port with the lower value has the higher priority. In the same
condition, the port with the highest priority will be elected as the root
port in CIST.
Ext-Path Cost: Enter the value of the external path cost. The default setting is Auto,
which means the port calculates the path cost automatically
according to the port’s link speed.
In MSTP, External path cost is the path cost of the port in CST. The
port with the lowest external root path cost will be elected as the
root port in CIST.
In STP/RSTP, external path cost indicates the path cost of the port in
the spanning tree. The port with the lowest external root path cost
will be elected as the root port.
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Int-Path Cost: Enter the value of the internal path cost. The default setting is Auto,
which means the port calculates the path cost automatically
according to the port’s link speed.
Internal path cost is the path cost of the port in IST. The port with the
lowest internal root path cost will be elected as the root port in IST.
Note: Internal path cost is a parameter configured in MSTP. You
need not configure it if the spanning tree mode is STP/RSTP.
Edge Port: Enable or disable Edge Port. By default, it is disabled.
The edge port can transit its state from blocking t
o forwarding
directly. If the port is connected to an end device, like a PC, it is
recommended to set the port as an edge port.
P2P Link:
Select the P2P link status. If the two ports in the P2P link are a root
port and a designated port, they can transit
their states to
forwarding directly.
Three options are supported: Auto, Open(Force) and Close(Force).
By default, it is Auto.
Auto: The switch automatically detects if the port is connected to a
P2P link, then determines the status is Open or Close.
Open(Force): The port is manually identified as connected to a P2P
link.
Close(Force): The port is manually identified as not connected to a
P2P link
MCheck:
Select whether to do MCheck operation on the port. Unchange
means no MCheck operation.
If a port on an MSTP-
enabled device is connected to a
STP/RSTP-
enabled device, the port switches to the STP/RSTP
compatible mode. If the STP/RSTP-enabled device is powered off or
disconnected from the MSTP-
enabled device, the port cannot
switch back to MSTP mode. In this case, you can switch the port to
MSTP mode by enabling MCheck operation.
Note: MCheck is configured in MSTP. You need not configure it if the
spanning tree mode is STP/RSTP.
Port Mode:
Display the spanning tree mode of the port.
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Port Role: Displays the role of the port played in the STP Instance.
Root Port: Indicates the port that has the lowest root path cost
from this bridge to the Root Bridge and forwards packets to the
root.
Designated Port: Indicates the port that forwards packets to a
downstream network segment or switch.
Master Port: Indicates the port that connects a MST region to
the common root. The path from the master port to the
common root is the shortest path between this MST region and
the common root.
Alternate Port: Indicates the port that can be a backup port of a
root or master port.
Backup Port:
Indicates the port that is the backup port of a
designated port.
Disabled: Indicates the port that is not participating in the STP.
Port Status: Displays the working status of the port.
Forwarding: The port receives and sends BPDUs, and forwards
user data.
Learning: The port receives and sends BPDUs, and drops the
other packets.
Blocking: The port only receives BPDUs and drops the other
packets.
Disconnected: The port is enabled with spanning tree function
but not connected to any device.
LAG:
Displays the LAG number which the port belongs to.
Note:
1. Configure the ports connected directly to terminals as edge ports and enable the BPDU
protection function as well. This not only enables these ports to transit to forwarding state
rapidly but also secures your network.
2. When the link of a port is configured as a point-to-point link, the spanning tree instances
owning this port are configured as point-to-point links. If the physical link of a port is not a
point-to-point link and you forcibly configure the link as a point-to-point link, temporary
loops may be incurred.
8.3 MSTP Instance
MSTP combines VLANs and spanning tree together via VLAN-instance mapping table
(VLAN-spanning-tree mapping). By adding MSTP instances, it binds several VLANs to an
instance to realize the load balance based on instances.
Only when the switches have the same MST region name, MST region revision and
VLAN-Instance mapping table, the switches can be regarded as in the same MST region.
The MSTP Instance function can be implemented on Region Config, Instance Config and
Instance Port Config pages.
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8.3.1 Region Config
On this page you can configure the name and revision of the MST region.
Choose the menu Spanning Tree→MSTP Instance→Region Config to load the following page.
Figure 8-7 Region Config
Configuration Procedure:
Set the name and revision level to specify an MSTP region.
Entry Description:
Region Config
Region Name: Configure the name for an MST region using up to 32 characters. By
default, it is the MAC address of the switch.
Revision:
Enter the revision from 0 to 65535 for MST region identification. By
default, it is 0.
8.3.2 Instance Config
Instance Configuration, a property of MST region, is used to describe the VLAN to Instance
mapping configuration. You can assign VLAN to different instances appropriate to your needs.
Every instance is a VLAN group independent of other instances and CIST.
Choose the menu Spanning Tree→MSTP Instance→Instance Config to load the following
page.
Figure 8-8 Instance Config
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Configuration Procedure:
1) Enter the instance ID and the corresponding VLAN ID, and click Add.
2) Configure the priority of the switch in the desired instance, and click Apply.
Entry Description:
VLAN-Instance Mapping
Instance ID:
Enter the corresponding instance ID.
VLAN ID: Enter the desired VLAN ID. Click 'Add' button, the new VLAN ID will
be added to the corresponding instance and
the previous VLAN
won't be replaced. Click 'Delete' button, the VLAN will be delete from
the corresponding instance.
Instance Config
Select:
Select the desired Instance ID for configuration. It is multi-optional.
Instance ID:
Displays Instance ID of the switch.
Status:
Displays status of the instance.
Priority: Enter a value from 0 to 61440 to specify the priority of the switch,
which is divisible by 4096, and the default value is 32768. The switch
with the lower value has the higher priority, and the switch with the
highest priority will be elected as the root bridge in the desired
instance.
VLAN ID: Enter the VLAN ID mapped to the corresponding instance ID. After
the modification, the previous VLAN will be cleared and mapped to
the CIST.
Show All: Click the Show All
button to show all VLAN IDs mapped to the
instance.
Clear All: Click the Clear All button to clear up all VLAN from the instance. The
cleared VLAN will be automatically mapped to the CIST.
Note:
In a network with both GVRP and MSTP enabled, GVRP packets are forwarded along the CIST. If
you want to announce a specific VLAN through GVRP, please be sure to map the VLAN to the
CIST when configuring the MSTP VLAN-instance mapping table. For detailed introduction of
GVRP, please refer to GVRP function page.
8.3.3 Instance Port Config
A port can play different roles in different spanning tree instance. On this page you can
configure the parameters of the ports in different instances as well as view status of the ports
in the specified instance.
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Choose the menu Spanning Tree→MSTP Instance→Instance Port Config to load the
following page.
Figure 8-9 Instance Port Config
Configuration Procedure:
1) Select the desired instance ID for its port configuration.
2) Configure port parameters in the desired instance.
Instance ID Select
Instance ID:
Select the desired instance ID for its port configuration.
Instance Port Config
UNIT:
Select the desired unit or LAGs.
Select:
Select the desired port to specify its priority and path cost. It is
multi-optional.
Port:
Displays the port number of the switch.
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Priority: Enter the value of port priority from 0 to 240, which is divisible by 16,
and the default value is 128.
The port with the lower value has the higher priority. In the same
condition, the port with the highest priority will be elected as the root
port in the desired instance.
Path Cost:
Enter the value of the path cost. The default setting is Auto, which
means the port calculates the path cost automatically according to
the port’s link speed.
It is the path cost of the port in the desired instance. The port with
the lowest path cost will be elected as the root of the desired
instance.
Port Role: Displays the role that the port plays in the desired instance.
Root Port: Indicates the port is the root port.
Designated Port: Indicates the port is the designated port.
Alternate Port: Indicates the port is a backup of a root port.
Backup Port: Indicates the port is a backup of a designated port.
Disabled: Indicates the port is not participating in the spanning tree.
Port Status: Displays the port status.
Forwarding: The port receives and sends BPDUs, and forwards user
data.
Learning: The port receives and sends BPDUs, and drops the other
packets.
Blocking: The port only receives BPDUs and dro
ps the other
packets.
Disconnected: The port is enabled with spanning tree function but
not connected to any device.
LAG:
Displays the LAG which the port belongs to.
Note:
The port status of one port in different spanning tree instances can be different.
Global configuration Procedure for Spanning Tree function:
Step
Operation
Description
1 Make clear roles the switches
play in spanning tree
instances: root bridge or
designated bridge
Preparation.
2 Globally configure Spanning
Tree parameters.
Required. Enable Spanning Tree function on the switch
and configure MSTP parameters on Spanning
Tree→STP Config→STP Config page.
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3 Configure CIST parameters
for ports
Required. Configure CIST
parameters for ports on
Spanning Tree→Port Config→Port Config page.
4 Configure the MST region Required. Create the MST region, VLAN-Instance
mapping and the priority of the switch
in the
corresponding region on Spanning Tree→MSTP
Instance→Region Config and Instance Config page.
5
Configure MSTP parameters
for instance ports
Optional. Configure different instances in the MST
region and configure MSTP parameters for instance
ports on Spanning Tree→MSTP Instance→Instance
Port Config page.
8.4 STP Security
Configuring protection function for devices can prevent devices from any malicious attack
against STP features. The STP Security function can be implemented on Port Protect page.
Port Protect function is to prevent the devices from any malicious attack against STP features.
8.4.1 Port Protect
STP Security prevents the loops caused by wrong configurations or BPDU attacks. It contains
Loop Protect, Root Protect, BPDU Protect, BPDU Filter, TC Protect and BPDU flood functions.
Loop Protect
Loop Protect function is used to prevent loops caused by link congestions or link failures. It is
recommended to enable this function on root ports and alternate ports.
If the switch cannot receive BPDUs because of link congestions or link failures, the root port
will become a designated port and the alternate port will transit to forwarding status, so loops
will occur.
With Loop Protect function enabled, the port will temporarily transit to blocking state when the
port does not receive BPDUs. After the link restores to normal, the port will transit to its normal
state, so loops can be prevented.
Root Protect
Root Protect function is used to ensure that the desired root bridge will not lose its position. It
is recommended to enable this function on the designated ports of the root bridge.
Generally, the root bridge will lose its position once receiving higher-priority BPDUs caused by
wrong configurations or malicious attacks. In this case, the spanning tree will be regenerated,
and traffic needed to be forwarded along high-speed links may be lead to low-speed links.
With root protect function enabled, when the port receives higher-priority BDPUs, it will
temporarily transit to blocking state. After two times of forward delay, if the port does not
receive any higher-priority BDPUs, it will transit to its normal state.
TC Protect
TC Protect function is used to prevent the switch from frequently removing MAC address
entries and TC-BPDU flooding.
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A switch removes MAC address entries upon receiving TC-BPDUs (the packets used to
announce changes in the network topology). If a user maliciously sends a large number of
TC-BPDUs to a switch in a short period, the switch will be busy with removing MAC address
entries, which may decrease the performance and stability of the network.
With TC Protect function enabled, the port will drop the received TC-BPDUs and will not
forward them.
BPDU Protect
BPDU Protect function is used to prevent the port from receiving BPUDs. It is recommended to
enable this function on edge ports.
Normally edge ports do not receive BPDUs, but if a user maliciously attacks the switch by
sending BPDUs, the system automatically configures these ports as non-edge ports and
regenerates the spanning tree.
With BPDU protect function enabled, the edge port will be shut down when it receives BPDUs,
and reports these cases to the administrator. Only the administrator can restore it.
BPDU Filter
BPDU filter function is to prevent BPDU flooding in the network. It is recommended to enable
this function on edge ports.
If a switch receives malicious BPDUs, it forwards these BPDUs to the other switches in the
network, and the spanning tree will be continuously regenerated. In this case, the switch
occupies too much CPU or the protocol status of BPDUs is wrong.
With BPDU filter function enabled, the port does not receive or forward BPDUs, but it sends out
its own BPDUs, preventing the switch from being attacked by BPDUs.
BPDU Flood
BPDU flood function is to control BPDUs forwarding when spanning tree function is globally
disabled.
Generally, if a port receives BPDUs, it will forward them to all the other ports. With BPDU flood
function enabled, the port can only forward BPDUs to other BPDU-flood-enabled ports.
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Choose the menu Spanning Tree→STP Security→Port Protect to load the following page.
Figure 8-10 Port Protect
Configuration Procedure:
Configure the Port Protect features for the selected ports, and click Apply.
Entry Description:
Port Protect
UNIT:
Select the desired unit or LAGs.
Select:
Select the desired port for port protect configuration. It is
multi-optional.
Port:
Displays the port number of the switch.
Loop Protect: Enable or disable the Loop Protect function. It is recommended to
enable this function on root ports and alternate ports.
Loop Protect function is used to prevent loops caused by link
congestions or link failures. With Loop Protect function enabled, the
port will temporarily transit to blocking state when it does not
receive BPDUs. After the link restores to normal, the port will transit
to its normal state, so loops can be prevented.
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Root Protect:
Enable or disable the Root Protect function. It is recommended to
enable this function on the designated ports of the root bridge.
Root Protect function is used to ensure that the desired root bridge
will not lose its position. With root protect function enabled, the port
will temporarily transit to blocking state when it receives
higher-priority BDPUs. After two times of forward delay, if the port
does not receive any higher-priority BDPUs, it will transit to its
normal state.
TC Protect: Enable or disable the TC Protect function. It is It is recommended to
enable this function on the ports of non-root switches.
TC Protect function is used to prevent the switch from frequently
removing MAC address entries. With TC protect function enabled,
the switch will drop TC-BPDUs.
BPDU Protect: Enable or disable the BPDU Protect function. It is It is recommended
to enable this function on edge ports.
BPDU Protect function is used to prevent the edge port from
receiving BPUDs. With BPDU protect function enable
d, the edge
port will be shut down when it receives BPDUs, and reports these
cases to the administrator. Only the administrator can restore it.
BPDU Filter: Enable or disable the BPDU Filter function. It is It is recommended to
enable this function on edge ports.
BPDU filter function is to prevent BPDU flooding in the network. With
BPDU filter function enabled, the port does not receive or forward
BPDUs, but it sends out its own BPDUs, preventing the switch from
being attacked by BPDUs.
BPDU Flood Enable or disable the BPDU Flood function.
With BPDU flood function enabled, the port can only forward BPDUs
to other BPDU-flood-enabled ports.
LAG:
Displays the LAG which the port belongs to.
8.5 Application Example for MSTP Function
Network Requirements
Switch A, B, C, D and E all support MSTP function.
A is the central switch.
B and C are switches in the convergence layer. D, E and F are switches in the access layer.
There are 6 VLANs labeled as VLAN101-VLAN106 in the network.
All switches run MSTP and belong to the same MST region.
The data in VLAN101, 103 and 105 are transmitted in Instance 1 with B as the root bridge.
The data in VLAN102, 104 and 106 are transmitted in Instance 2 with C as the root bridge.
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Network Diagram
Configuration Procedure
Configure Switch A:
Step
Operation
Description
1 Configure ports On VLAN→802.1Q VLAN page, configure the link type of the
related ports as Trunk, and add the ports to
VLAN101-
VLAN106. The detailed instructions can be found
in the section 802.1Q VLAN.
2 Enable MSTP function On Spanning Tree→STP Config→STP Config page, enable
STP function and select MSTP version.
On Spanning Tree→Port Config→Port Config page, enable
MSTP function for the port.
3
Configure the region
name and the revision of
MST region
On Spanning Tree→MSTP Instance→Region Config page,
configure the region as TP-Link and keep the default revision
setting.
4 Configure
VLAN-Instance mapping
table of the MST region
On Spanning Tree→MSTP Instance→Instance Config page,
configure VLAN-
Instance mapping table. Map VLAN 101,
103 and 105 to Instance 1; map VLAN 102, 104 and 106 to
Instance 2.
Configure Switch B:
Step
Operation
Description
1 Configure ports On VLAN→802.1Q VLAN page, configure the link type of the
related port
s as Trunk, and add the ports to
VLAN101-
VLAN106. The detailed instructions can be found
in the section 802.1Q VLAN.
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Step
Operation
Description
2 Enable MSTP function On Spanning Tree→STP Config→STP Config page, enable
STP function and select MSTP version.
On Spanning Tree→Port Config→Port Config page, enable
MSTP function for the port.
3
Configure the region
name and the revision of
MST region
On Spanning Tree→MSTP Instance→Region Config page,
configure the region as TP-Link and keep the default revision
setting.
4 Configure
VLAN-Instance mapping
table of the MST region
On Spanning Tree→MSTP Instance→Instance Config page,
configure VLAN-
Instance mapping table. Map VLAN 101,
103 and 105 to Instance 1; map VLAN 102, 104 and 106 to
Instance 2.
5 Conf
igure switch B as
the root bridge of
Instance 1
On Spanning Tree→MSTP Instance→Instance Config page,
configure the priority of Switch B in Instance 1 as 0.
6
Configure switch B as
the designated bridge of
Instance 2
On Spanning Tree→MSTP Instance→Instance Config page,
configure the priority of Instance 2 to be 4096.
Configure Switch C:
Step
Operation
Description
1 Configure ports On VLAN→802.1Q VLAN page, configure the link type of the
related ports as Trunk, and add the ports to
VLAN101-VLAN106. The detailed instructions can be found
in the section 802.1Q VLAN.
2 Enable STP function On Spanning Tree→STP Config→STP Config page, enable
STP function and select MSTP version.
On Spanning Tree→Port Config→Port Config page, enable
MSTP function for the port.
3
Configure the region
name and the revision of
MST region
On Spanning Tree→MSTP Instance→Region Config page,
configure the region as TP-Link and keep the default revision
setting.
4 Configure
VLAN-Instance mapping
table of the MST region
On Spanning Tree→MSTP Instance→Instance Config page,
configure VLAN-
Instance mapping table. Map VLAN 101,
103 and 105 to Instance 1; map VLAN 102, 104 and 106 to
Instance 2.
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Step
Operation
Description
5
Configure switch C as
the designated bridge of
Instance 1
On Spanning Tree→MSTP Instance→Instance Config page,
configure the priority of Instance 1 to be 4096.
6
Configure switch C as
the root bridge of
Instance 2
On Spanning Tree→MSTP Instance→Instance Config page,
configure the priority of Switch C in Instance 2 as 0.
Configure switch D:
Step
Operation
Description
1 Configure ports On VLAN→802.1Q VLAN page, configure the link type of the
related ports as Trunk, and add the ports to
VLAN101-
VLAN106. The detailed instructions can be found
in the section 802.1Q VLAN.
2 Enable STP function On Spanning Tree→STP Config→STP Config page, enable
STP function and select MSTP version.
On Spanning Tree→Port Config→Port Config page, enable
MSTP function for the port.
3
Configure the region
name and the revision of
MST region
On Spanning Tree→MSTP Instance→Region Config page,
configure the region as TP-Link and keep the default revision
setting.
4 Configure
VLAN-Instance mapping
table of the MST region
On Spanning Tree→MSTP Instance→Instance Config page,
configure VLAN-
Instance mapping table. Map VLAN 101,
103 and 105 to Instance 1; map VLAN 102, 104 and 106 to
Instance 2.
The configuration procedure for switch E and F is the same with that for switch D.
The topology diagram of the two instances after the topology is stable
For Instance 1 (VLAN 101, 103 and 105), the red paths in the following figure are connected
links; the gray paths are the blocked links.
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For Instance 2 (VLAN 102, 104 and 106), the blue paths in the following figure are connected
links; the gray paths are the blocked links.
Suggestion for Configuration
Enable TC Protect function for all the ports of switches.
Enable Root Protect function for all the ports of root bridges.
Enable Loop Protect function for the non-edge ports.
Enable BPDU Protect function or BPDU Filter function for the edge ports which are connected
to the PC and server.
Return to CONTENTS
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Chapter 9 Multicast
Multicast Overview
In the network, packets are sent in three modes: unicast, broadcast and multicast. In unicast,
the source server sends separate copy information to each receiver. When a large number of
users require this information, the server must send many pieces of information with the same
content to the users. Therefore, large bandwidth will be occupied. In broadcast, the system
transmits information to all users in a network. Any user in the network can receive the
information, no matter the information is needed or not.
Point-to-multipoint multimedia business, such as video conferences and VoD
(video-on-demand), plays an important part in the information transmission field. Suppose a
point to multi-point service is required, unicast is suitable for networks with sparsely users,
whereas broadcast is suitable for networks with densely distributed users. When the number of
users requiring this information is not certain, unicast and broadcast deliver a low efficiency.
Multicast solves this problem. It can deliver a high efficiency to send data in the point to
multi-point service, which can save large bandwidth and reduce the network load. In multicast,
the packets are transmitted in the following way as shown in the following figure.
Figure 9-1 Information transmission in the multicast mode
Features of multicast:
1. The number of receivers is not certain. Usually point-to-multipoint transmission is
needed;
2. Multiple users receiving the same information form a multicast group. The multicast
information sender just need to send the information to the network device once;
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3. Each user can join and leave the multicast group at any time;
4. Real time is highly demanded and certain packets drop is allowed.
Multicast Address
1. Multicast IP Address:
As specified by IANA (Internet Assigned Numbers Authority), Class D IP addresses are used as
destination addresses of multicast packets. The multicast IP addresses range from
224.0.0.0~239.255.255.255. The following table displays the range and description of several
special multicast IP addresses.
Multicast IP address range
Description
224.0.0.0～224.0.0.255 Reserved multicast addresses for routing protocols
and other network protocols
224.0.1.0
～
224.0.1.255
Addresses for video conferencing
239.0.0.0 ～
239.255.255.255
Local management multicast addresses, which are
used in the local network only
Table 9-1 Range of the special multicast IP
2. Multicast MAC Address:
When a unicast packet is transmitted in an Ethernet network, the destination MAC address is
the MAC address of the receiver. When a multicast packet is transmitted in an Ethernet
network, the destination is not a receiver but a group with uncertain number of members, so a
multicast MAC address, a logical MAC address, is needed to be used as the destination
address.
As stipulated by IANA, the high-order 24 bits of a multicast MAC address begins with 01-00-5E
while the low-order 23 bits of a multicast MAC address are the low-order 23 bits of the
multicast IP address. The mapping relationship is described as the following figure.
Figure 9-2 Mapping relationship between multicast IP address and multicast MAC address
The high-order 4 bits of the IP multicast address are 1110, identifying the multicast group. Only
23 bits of the remaining low-order 28 bits are mapped to a multicast MAC address. In that way,
5 bits of the IP multicast address is not utilized. As a result, 32 IP multicast addresses are
mapped to the same MAC address.
Multicast Address Table
The switch is forwarding multicast packets based on the multicast address table. As the
transmission of multicast packets cannot span the VLAN, the first part of the multicast address
table is VLAN ID, based on which the received multicast packets are forwarded in the VLAN
owning the receiving port. The multicast address table is not mapped to an egress port but a
group port list. When forwarding a multicast packet, the switch looks up the multicast address
table based on the destination multicast address of the multicast packet. If the corresponding
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entry cannot be found in the table, the switch will broadcast the packet in the VLAN owning the
receiving port. If the corresponding entry can be found in the table, it indicates that the
destination address should be a group port list, so the switch will duplicate this multicast data
and deliver each port one copy. The general format of the multicast address table is described
as Figure 9-3 below.
VLAN ID
Multicast IP
Port
Figure 9-3 Multicast Address Table
IGMP Snooping
In the network, the hosts apply to the near Router for joining (leaving) a multicast group by
sending IGMP (Internet Group Management Protocol) messages. When the up-stream device
forwards down the multicast data, the switch is responsible for sending them to the hosts.
IGMP Snooping is a multicast control mechanism, which can be used on the switch for dynamic
registration of the multicast group. The switch, running IGMP Snooping, manages and controls
the multicast group via listening to and processing the IGMP messages transmitted between the
hosts and the multicast router, thereby effectively prevents multicast groups being broadcasted
in the network.
The Multicast module is mainly for multicast management configuration of the switch, including
four submenus: IGMP Snooping, Multicast IP, Multicast Filter, Packet Statistics.
9.1 IGMP Snooping
IGMP Snooping Process
The switch, running IGMP Snooping, listens to the IGMP messages transmitted between the
host and the router, and tracks the IGMP messages and the registered port. When receiving
IGMP report message, the switch adds the port to the multicast address table; when the switch
listens to IGMP leave message from the host, the router sends the Group-Specific Query
message of the port to check if other hosts need this multicast, if yes, the router will receive
IGMP report message; if no, the router will receive no response from the hosts and the switch
will remove the port from the multicast address table. The router regularly sends IGMP query
messages. After receiving the IGMP query messages, the switch will remove the port from the
multicast address table if the switch receives no IGMP report message from the host within a
period of time.
IGMP Messages
The switch, running IGMP Snooping, processes the IGMP messages of different types as
follows.
1. IGMP Query Message
IGMP query message, sent by the router, falls into two types, IGMP general query message and
IGMP group-specific-query message. The router regularly sends IGMP general message to
query if the multicast groups contain any member. When receiving IGMP leave message, the
receiving port of the router will send IGMP group-specific-query message to the multicast
group and the switch will forward IGMP group-specific-query message to check if other
members in the multicast group of the port need this multicast.
When receiving IGMP general query message, the switch will forward them to all other ports in
the VLAN owning the receiving port. The receiving port will be processed: if the receiving port
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is not a router port yet, it will be added to the router port list with its router port time specified; if
the receiving port is already a router port, its router port time will be directly reset.
When receiving IGMP group-specific-query message, the switch will send the group-specific
query message to the members of the multicast group being queried.
2. IGMP Report Message
IGMP report message is sent by the host when it applies for joining a multicast group or
responses to the IGMP query message from the router.
When receiving IGMP report message, the switch will send the report message via the router
port in the VLAN as well as analyze the message to get the address of the multicast group the
host applies for joining. The receiving port will be processed: if the receiving port is a new
member port, it will be added to the multicast address table with its member port time specified;
if the receiving port is already a member port, its member port time will be directly reset.
3. IGMP Leave Message
The host, running IGMPv1, does not send IGMP leave message when leaving a multicast group,
as a result, the switch cannot get the leave information of the host momentarily. However, after
leaving the multicast group, the host does not send IGMP report message any more, so the
switch will remove the port from the corresponding multicast address table when its member
port time times out. The host, running IGMPv2 or IGMPv3, sends IGMP leave message when
leaving a multicast group to inform the multicast router of its leaving.
When receiving IGMP leave message, the querier will forward IGMP group-specific-query
message to check if other members in the multicast group of the port need this multicast and
reset the member port time to the leave time. When the leave time times out, the switch will
remove the port from the corresponding multicast group. If no other member is in the group
after the port is removed, the switch will send IGMP leave message to the router and remove
the whole multicast group.
IGMP Snooping Fundamentals
1. Ports
Router Port: Indicates the switch port directly connected to the multicast router.
Member Port: Indicates a switch port connected to a multicast group member.
2. Timers
Router Port Time: Within the time, if the switch does not receive IGMP query message from the
router port, it will consider this port is not a router port any more. The default value is 300
seconds.
Member Port Time: Within the time, if the switch does not receive IGMP report message from
the member port, it will consider this port is not a member port any more. The default value is
260 seconds.
Leave Time: Indicates the interval between the switch receiving a leave message from a host
and the switch removing the host from the multicast groups. The default value is 1 second.
The IGMP Snooping function can be implemented on Snooping Config, Port Config, VLAN
Config and Multicast VLAN pages.
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9.1.1 Snooping Config
To configure the IGMP Snooping on the switch, please firstly configure IGMP global
configuration and related parameters on this page.
If the multicast address of the received multicast data is not in the multicast address table, the
switch will broadcast the data in the VLAN. When Unknown Multicast Discard feature is enabled,
the switch drops the received unknown multicast so as to save the bandwidth and enhance the
process efficiency of the system. Please configure this feature appropriate to your needs.
Choose the menu Multicast→IGMP Snooping→Snooping Config to load the following page.
Figure 9-4 Basic Config
The following entries are displayed on this screen:
Global Config
IGMP Snooping: Enable or disable IGMP Snooping function g
lobally on the
switch.
Unknown Multicast:
Configure the way how the switch processes the multicast data
sent to unknown multicast groups as Forward or Discard.
Unknown multicast groups are multicast groups whose
destination multicast address is not in the multicast forwarding
table of the switch.
Header Validation:
Select Enable/Disable the validation of 2 IGMP header fields ToS
(Type of Service) and Router Alert options. The fields validated
depend on the IGMP version being used. Regardless of whether
open the validation, TTL(Time To Live) must be 1.
•IGMPv2 - Router Alert fields are validated.
•IGMPv3 - ToS and Router Alert fields are validated
IGMP Snooping Status
Description:
Displays IGMP Snooping status.
Member:
Displays the member of the corresponding status.
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9.1.2 Port Config
On this page you can configure the IGMP feature for ports of the switch.
Choose the menu Multicast→IGMP Snooping→Port Config to load the following page.
Figure 9-5 Port Config
The following entries are displayed on this screen:
Port Config
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired port for IGMP Snooping feature
configuration. It is multi-optional.
Port:
Displays the port of the switch.
IGMP Snooping:
Enable or disable IGMP Snooping for the desired port.
Fast Leave: Enable or disable Fast Leave feature for the desired port. If
Fast Leave is enabled for a port, the switch will immediately
remove this port from the multicast group upon receiving IGMP
leave messages.
Member Port Time:
Member ports are ports connected to multicast group
members on the switch. A port is considered to be a member
port when it is added to a multicast group. The member port
ages if the switch does not receive IGMP membership report
message from the member port within the member port time.
The switch will no longer consider this port as a member port
and delete it from the multicast forwarding table. The valid
values are from 60 to 600 seconds.
Router Port Time: Router ports are ports connected to Layer 3 devices on the
switch. The router port ages if the switch does not receive
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IGMP query message from the router port within the router
port time. The switch will no longer consider this port as a
router port and delete it from the router port table. The valid
values are from 60 to 600 seconds.
Max Response
Time:
Enter the host’s maximum response time to general query
messages in a range of 1 to 25 seconds.
Profile ID: Enter the profile ID you create to bind the profile to the port.
One port can only be bound to one profile.
LAG:
Displays the LAG number which the port belongs to.
Note:
1. Fast Leave on the port is effective only when the host supports IGMPv2 or IGMPv3.
2. When both Fast Leave feature and Unknown Multicast Discard feature are enabled, the
leaving of a user connected to a port owning multi-user will result in the other users
intermitting the multicast business.
9.1.3 VLAN Config
Multicast groups established by IGMP Snooping are based on VLANs. On this page you can
configure different IGMP parameters for different VLANs.
Choose the menu Multicast→IGMP Snooping→VLAN Config to load the following page.
Figure 9-6 VLAN Config
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The following entries are displayed on this screen:
VLAN Config
VLAN ID: Enter the VLAN ID to enable IGMP Snooping for the desired
VLAN.
Fast Leave: Enable or disable Fast Leave feature in this VLAN. If Fast Leave
is enabled, the switch will immediately remove this port from
the multicast group upon receiving IGMP leave messages.
Report
Suppression:
If this function is enabled, the switch will only forward the first
IGMP report message to Layer 3 devices and suppress
subsequent IGMP report messages from the same multicast
group during one query interval, which reduces the number of
IGMP packets.
Member Port Time: Specify the aging time of the member port. Within this time, if
the switch doesn’t receive IGMP report message from the
member port, it will consider this port is not a member port any
more.
Router Port Time: Specify the aging time of the router port. Within this time, if the
switch doesn’t receive IGMP query message from the router
port, it will consider this port is not a router port any more.
Max Response
Time:
Enter the host’s maximum response time to general query
messages in a range of 1 to 25 seconds.
Router Ports: Enter the static router port which is mainly used in the network
with stable topology.
UNIT:
Select the unit ID of the desired member in the stack.
VLAN Table
Select:
Select the desired VLAN ID for configuration. It is multi-optional.
VLAN ID:
Displays the VLAN ID.
Fast Leave:
Displays the fast leave feature of the VLAN.
Report
Suppression:
Displays the report suppression feature of the VLAN.
Member Port Time:
Displays the member port time of the VLAN.
Router Port Time:
Displays the router port time of the VLAN.
Max Response
Time:
Displays the max response time of the VLAN.
Static Router Ports:
Displays the static router ports of the VLAN.
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Dynamic Router
Ports:
Displays the dynamic router ports of the VLAN.
Configuration procedure:
Step
Operation
Description
1
Enable IGMP Snooping
function
Required. Enable IGMP Snooping globally on the switch
on Multicast→IGMP Snooping→
Snooping Config
page.
2
Configure the multicast
parameters for VLANs
Optional. Configure the multicast parameters for VLANs
on Multicast→IGMP Snooping→VLAN Config page.
If a VLAN has no multicast parameters configuration, it
indicates the
IGMP Snooping is not enabled in the
VLAN, thus the multicast data in the VLAN will be
broadcasted.
9.1.4 Querier Config
In an IP multicast network that runs IGMP, a Layer 3 multicast device works as an IGMP querier
to send IGMP queries and manage the multicast table. But IGMP is not supported by the
devices in Layer 2 network. IGMP Snooping Querier can act as an IGMP Router in Layer 2
network. It can help to create and maintain multicast forwarding table on the switch with the
Query messages it generates.
Choose the menu Multicast→IGMP Snooping→Querier Config to load the following page.
Figure 9-7 Querier Config
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The following entries are displayed on this screen:
IGMP Snooping Querier Config
Querier Mode: Enter t
he Query mode which for the IGMP snooping querier on
the device. When enabled, the IGMP snooping querier sends out
periodic IGMP queries that trigger IGMP report messages from
the switches that want to receive IP multicast traffic. The IGMP
snooping featur
e listens to these IGMP reports to establish
appropriate forwarding.
Query VLAN
Address:
Enter the General Query Message source IP address.
IGMP Version:
Enter the IGMP version used in periodic IGMP queries.
Query Interval: Enter the time interval of
sending a general query frame by IGMP
Snooping Querier.
Expiry Interval:
Enter the Expiry Interval which is amount of time the device
remains in non-
querier mode after it has discovered that there is
a multicast querier in the network.
IGMP Snooping Querier Table
Select:
Select the desired entry. It is multi-optional.
VLAN ID:
Displays the ID of the VLAN that enables IGMP Snooping
Querier.
Query Mode:
Displays the Querier Mode of VLAN.
Election Participate:
Displays the Election Participate of VLAN.
Querier VLAN
Address:
Displays the General Query Message source IP address.
Operational State:
Displays the Operational State.
Last Querier
Address:
Displays the Last Querier Address.
Operational
Version:
Displays the Operational Version.
Operational Max
Response Time:
Displays the value of Operational Max Response Time.
Last Querier Address Table
VLAN ID:
Displays the VLAN ID.
Last Querier
Address:
Displays the Last Querier Address.
IGMP Version:
Displays the Last Querier Version.
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9.1.5 Profile Config
On this page you can configure an IGMP profile.
Choose the menu Multicast→Multicast Filter→Profile Config to load the following page.
Figure 9-8 Profile Create
The following entries are displayed on this screen:
Profile Creation
Profile ID:
Specify the Profile ID you want to create, and it should be a
number between 1 and 999.
Mode: The attributes of the profile.
Permit: Only permit the IP address within the IP range and
deny others.
Deny: Only deny the IP add
ress within the IP range and
permit others.
Search Option
Profile ID:
Enter the profile ID the desired entry must carry.
IGMP Profile Info
Select:
Select the desired entry for configuration.
Profile ID:
Displays the profile ID.
Mode:
Displays the attribute of the profile.
Permit: Only permit the IP address within the IP range and
deny others.
Deny: Only deny the IP address within the IP range and
permit others.
Bind Ports:
Displays the ports that the Profile bound to.
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Operation: Click the Edit button to configure the mode or IP-
range of the
Profile.
Figure 9-9 Profile Config
Profile Mode
Profile ID:
Displays the Profile ID.
Mode: Configure the filtering mode of the profile.
Permit: Only permit the
IP address within the IP range and
deny others.
Deny: Only deny the IP address within the IP range and
permit others.
Add IP-range
Start IP:
Enter the start IP address of the IP range.
End IP:
Enter the end IP address of the IP range.
IP-range Table
Select:
Select to delete the IP range entry.
Index:
Displays the index of the IP range.
Start IP:
Displays the start IP address of the IP range.
End IP:
Displays the end IP address of the IP range.
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9.2 MLD Snooping
MLD Snooping
Multicast Listener Discovery (MLD) snooping is applied for efficient distribution of IPv6
multicast data to clients and routers in a Layer 2 network. With MLD snooping, IPv6 multicast
data is selectively forwarded to a list of ports that want to receive the data, instead of being
flooded to all ports in a VLAN. The list is constructed and maintained by snooping IPv6
multicast control packets. MLD snooping performs a similar function in IPv6 as IGMP snooping
in IPv4.
The switch, running MLD Snooping, listens to the MLD messages transmitted between the host
and the router, and tracks the MLD messages and the registered port. When receiving MLD
report message, the switch adds the port to the multicast address table; when the switch
listens to MLD Done message from the host, the router sends the Multicast-Address-Specific
Query message of the port to check if other hosts need this multicast, if yes, the switch will
receive MLD report message; if no, the switch will receive no response from the hosts and the
switch will remove the port from the multicast address table. The router regularly sends MLD
query messages. After receiving the MLD query messages, the switch will remove the port
from the multicast address table if the switch receives no MLD report message from the host
within a period of time.
MLD Snooping Fundamentals
1. MLD Messages
MLD Queries
：
MLD Queries include General Queries and Multicast-Address-Specific Queries
(MASQs) and are sent out from the MLD router.
MLD Reports
：
When a host wants to join a multicast group or responds to the MLD queries, it
will send out an MLD report.
MLD Done Messages
：
When a host wants to leave a multicast group, it will send out an MLD
Done message to inform the IPv6 multicast routers of its leave.
2. Relevant Ports of the Switch
Router Port: Indicates the switch port that links toward the MLD router.
Member Port: Indicates the switch port that links toward the multicast members.
3. Timers
Router Port Aging Time: Within this time, if the switch does not receive MLD queries from the
router port, it will delete this port from the router port list. The default value is 300 seconds.
Member Port Aging Time: Within this time, if the switch does not receive MLD reports from the
member port, it will delete this port from the MLD multicast group. The default value is 260
seconds.
General Query Interval: The interval between the multicast router sends out general queries.
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MLD Snooping Process
1. General Query
The MLD router regularly sends MLD general queries to query if the multicast groups contain
any members. When receiving MLD general queries, the switch will forward them to all other
ports in the VLAN. The receiving port will be processed: if the receiving port is not a router port
yet, it will be added to the router port list with its router port aging time specified; if the
receiving port is already a router port, its router port aging time will be directly reset.
2. Membership Report
The host will send MLD report messages when it applies for joining a multicast group or
responds to the MLD query message from the router.
When receiving MLD report message, the switch will forward the report message via the router
port in the VLAN, and analyze the message to get the address of the multicast group the host
applies for joining. If the multicast group does not exist, it will create the group entry. The
receiving port will be processed: if the receiving port is a new member port, it will be added to
the forward list of the multicast group with its member port aging time specified; if the receiving
port is already a member port, its member port aging time will be directly reset.
3. Member Leave
The host will send MLD Done message when leaving a multicast group to inform the router of
its leaving.
When Immediate Leave is not enabled in a VLAN and a Done message is received on a port of
this VLAN, the switch will generate MASQs on this port to check if there are other members in
this multicast group. The user can control when a port membership is removed for an exiting
address in terms of the number and interval of MASQs. If there is no Report message received
from this port during the switch maximum response time, the port on which the MASQ was sent
is deleted from the multicast group. If the deleted port is the last member of the multicast
group, the multicast group is also deleted. The switch will send Done message to the router
ports of the VLAN.
In IPv6，Layer 2 switches can use Multicast Listener Discovery (MLD) Snooping to limit the
flooding of multicast traffic by dynamically configuring Layer 2 interfaces so that IPv6 multicast
data is selectively forwarded to a list of ports that want to receive the data. This list is
constructed by snooping IPv6 multicast control packets.
The MLD Snooping function can be implemented on Snooping Config, Port Config, VLAN
Config, Querier Config and Profile Config pages.
9.2.1 Snooping Config
To configure the MLD Snooping on the switch, please firstly configure MLD global
configuration and related parameters on this page.
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Chose the menu Multicast→MLD Snooping→Snooping Config to load the following page.
Figure 9-10 MLD Snooping Config
The following entries are displayed on this screen:
Global Config
MLD Snooping:
Enable or disable MLD Snooping function globally.
Unknown Multicast: Choose to forward or drop unknown multicast data.
Unknown IPv6 multicast packets refer to those packets without
corresponding forwarding entries in the IPv6 multicast table:
When unknown multicast filter is enabled, the sw
itch will
discard all received unknown IPv6 multicast packets;
When unknown multicast filer is disabled, all unknown IPv6
multicast packets are flooded in the ingress VLAN.
MLD Snooping Status
Description:
Displays MLD Snooping status.
Member:
Displays the member of the corresponding status.
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9.2.2 Port Config
On this page you can configure MLD Snooping function with each single port.
Choose the menu Multicast→MLD Snooping→Port Config to load the following page.
Figure 9-11 Port Config
The following entries are displayed on this screen:
Port Config
UNIT:1/LAGS Click 1 to configure the physical ports. Click LAGS to
configure the link aggregation groups.
Select:
Select the port you want to configure.
Port:
Displays the port number.
MLD Snooping:
Select Enable/Disable MLD Snooping for the desired port.
Fast Leave: Select Enable/Disable Fast Leave feature for the desired port.
If Fast Leave is enabled for a port, the switch will immediately
remove this port from t
he multicast group upon receiving
MLD done messages.
Member Port Time:
Member ports are ports connected to multicast group
members on the switch. A port is considered to be a member
port when it is added to a multicast group. The member port
ages if the switch does not receive MLD membership report
message from the member port within the member port time.
The switch will no longer consider this port as a member port
and delete it from the multicast forwarding table. The valid
values are from 60 to 600 seconds.
Router Port Time: Router ports are ports connected to Layer 3 devices on the
switch. The router port ages if the switch does not receive
IGMP query message from the router port within the router
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port time. The switch will no longer consider this port as a
router port and delete it from the router port table. The valid
values are from 60 to 600 seconds.
Max Response Time: Enter the host’s maximum response time to general query
messages in a range of 1 to 25 seconds.
Profile ID: Enter the profile ID you create to bind the profile to the port.
One port can only be bound to one profile.
LAG:
Displays the LAG number.
9.2.3 VLAN Config
Multicast groups established by MLD Snooping are based on VLANs. On this page you can
configure different MLD parameters for different VLANs.
Choose the menu Multicast→MLD Snooping→VLAN Config to load the following page.
Figure 9-12 VLAN Config
The following entries are displayed on this screen:
VLAN Config
VLAN ID: Enter the VLAN ID to enable MLD Snooping for the desired
VLAN.
Fast Leave: Enable or disable Fast Leave feature in this VLAN. If Fast Leave
is enabled, the switch will immediately remove this port from
the multicast group upon receiving MLD leave messages.
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Member Port Time: Specify the aging time of the member port. Within this time, if
the switch doesn’t receive MLD report message from the
member port, it will consider this port is not a member port any
more.
Router Port Time: Specify the aging time of the router port. Within this time, if the
switch doesn’t receive MLD query message from the router
port, it will consider this port is not a router port any more.
Max Response
Time:
Enter the host’s maximum response time to general query
messages in a range of 1 to 25 seconds.
Router Ports: Enter the static router port which is mainly used in the network
with stable topology.
UNIT:
Select the unit ID of the desired member in the stack.
VLAN Table
Select:
Select the desired VLAN ID for configuration. It is multi-optional.
VLAN ID:
Displays the VLAN ID.
Fast Leave:
Displays the fast leave feature of the VLAN.
Member Port Time:
Displays the member port time of the VLAN.
Router Port Time:
Displays the router port time of the VLAN.
Max Response
Time:
Displays the max response time of the VLAN.
Static Router Ports:
Displays the static router ports of the VLAN.
Dynamic Router
Ports:
Displays the dynamic router ports of the VLAN.
Configuration procedure:
Step
Operation
Description
1
Enable MLD Snooping
function
Required. Enable MLD Snooping globally on the switch on
Multicast→MLD Snooping→Snooping Config page.
2
Configure the multicast
parameters for VLANs
Optional. Configure the multicast parameters for VLANs
on Multicast→MLD Snooping→VLAN Config page.
If a VLAN has no multicast parameters configuration, it
indicates the MLD Snooping is not enabled in the VLAN,
thus the multicast data in the VLAN will be broadcasted.
9.2.4 Querier Config
In an IP multicast network that runs MLD, a Layer 3 multicast device works as an MLD querier to
send MLD queries and manage the multicast table. But MLD is not supported by the devices in
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Layer 2 network. MLD Snooping Querier can act as an MLD Router in Layer 2 network. It can
help to create and maintain multicast forwarding table on the switch with the Query messages
it generates.
Choose the menu Multicast→MLD Snooping→Querier Config to load the following page.
Figure 9-13 Packet Statistics
The following entries are displayed on this screen:
MLD Snooping Querier Config
Querier Mode:
Enter the Query mode which for the MLD snooping querier on
the device. When enabled, the MLD snooping querier sends out
periodic MLD queries that trigger MLD report messages from
the switches that want to receive IP multicast traffic. The MLD
snooping
feature listens to these MLD reports to establish
appropriate forwarding.
Query VLAN
Address:
Enter the General Query Message source IP address.
MLD Version:
Enter the MLD version used in periodic MLD queries.
Query Interval: Enter the time interval of
sending a general query frame by MLD
Snooping Querier.
Expiry Interval:
Enter the Expiry Interval which is amount of time the device
remains in non-
querier mode after it has discovered that there is
a multicast querier in the network.
MLD Snooping Querier Table
Select:
Select the desired entry. It is multi-optional.
VLAN ID:
Displays the ID of the VLAN that enables MLD Snooping Querier.
Query Mode:
Displays the Querier Mode of VLAN.
Election Participate:
Displays the Election Participate of VLAN.
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Querier VLAN
Address:
Displays the General Query Message source IP address.
Operational State:
Displays the Operational State.
Last Querier
Address:
Displays the Last Querier Address.
Operational
Version:
Displays the Operational Version.
Operational Max
Response Time:
Displays the value of Operational Max Response Time.
Last Querier Address Table
VLAN ID:
Displays the VLAN ID.
Last Querier
Address:
Displays the Last Querier Address.
MLD Version:
Displays the Last Querier Version.
9.2.5 Profile Config
On this page you can configure an MLD profile.
Choose the menu Multicast→Multicast Filter→Profile Config to load the following page.
Figure 9-14 Profile Create
The following entries are displayed on this screen:
Profile Creation
Profile ID:
Specify the Profile ID you want to create, and it should be a
number between 1 and 999.
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Mode: The attributes of the profile.
Permit: Only permit the IP address within the IP range and
deny others.
Deny: Only deny the IP address
within the IP range and
permit others.
Search Option
Profile ID:
Enter the profile ID the desired entry must carry.
MLD Profile Info
Select:
Select the desired entry for configuration.
Profile ID:
Displays the profile ID.
Mode:
Displays the attribute of the profile.
Permit: Only permit the IP address within the IP range and
deny others.
Deny: Only deny the IP address within the IP range and
permit others.
Bind Ports:
Displays the ports that the Profile bound to.
Operation: Click the Edit button to configure the mode or IP-
range of the
Profile.
Figure 9-15 Profile Config
Profile Mode
Profile ID:
Displays the Profile ID.
Mode: Configure the filtering mode of the profile.
Permit: Only permit the IP a
ddress within the IP range and
deny others.
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Deny: Only deny the IP address within the IP range and
permit others.
Add IP-range
Start IP:
Enter the start IP address of the IP range.
End IP:
Enter the end IP address of the IP range.
IP-range Table
Select:
Select to delete the IP range entry.
Index:
Displays the index of the IP range.
Start IP:
Displays the start IP address of the IP range.
End IP:
Displays the end IP address of the IP range.
9.3 MVR
Multicast VLAN Registration (MVR) allows a single multicast VLAN to be shared for multicast
member ports in different VLANs. In IGMP snooping, if member ports are in different VLANs, a
copy of the multicast streams is sent to each VLAN that has member ports. While MVR
provides a dedicated multicast VLAN to forward multicast traffic over the layer 2 network, to
avoid duplication of multicast streams for clients in different VLANs. Clients can dynamically
join or leave the multicast VLAN without interfering with their relationships in other VLANs.
Only one MVR multicast VLAN per switch or per stack is supported.
9.3.1 MVR Config
Use this page to view and configure the global settings for Multicast VLAN Registration (MVR).
Choose the menu Multicast→MVR→MVR Config to load the following page.
Figure 9-16 MVR Global Config
151
The following entries are displayed on this screen:
MVR Config
MVR:
Before configuring functions related to MVR, click Enable to
enable MVR function globally.
MVR Mode: Select the MVR mode.
Compatible: T
he switch working in Compatible mode does not
learn multicast groups, which means the MVR switch does not
forward IGMP reports from the hosts to the IGMP router. So the
IGMP router has to be statically configured to transmit all the
required multicast streams to the MVR switch.
Dynamic
: The MVR switch learns existing multicast groups by
snooping the IGMP queries from the IGMP router and forwarding
the IGMP reports from the hosts to the IGMP router on the
Multicast VLAN.
Multicast VLAN:
Specify the VLAN on which the multicast data will be received.
Query Response
Time:
Set the maximum time wait for the IGMP membership report on
a receiver port. When an IGMP query is sent from a receiver
port, the switch waits for the default or configured MVR
response time
for an IGMP group membership report before
removing the port from the multicast group. The value ranges
from 1 to 100 tenths of seconds.
Max Multicast
Groups:
Displays the max number of multicast groups that MVR
supports.
Current Multicast
Groups:
Displays the current number of the MVR groups.
9.3.2 Port Config
Use this page to configure MVR settings on specific ports. To configure the settings for one or
more ports, select each entry to modify and click Edit. The same MVR settings are applied to all
selected ports.
152
Choose the menu Multicast→MVR→Port Config to load the following page.
Figure9-17 MVR Port Config
The following entries are displayed on this screen:
Interface Config
UNIT:
Select the unit ID of the desired member in the stack.
Select: Select the desired port to configure MVR settings on the
specific interface. It is multi-optional.
Port:
Displays the port number of the switch.
Mode:
Enable or disable MVR on this port.
Type: Configure an port as one of the following type:
None: Non-MVR port.
Source: Configure the uplink ports that receive and send
multicast data as source ports. All source ports belong to the
multicast VLAN.
Receiver: The port where a listening port is connected to the
switch. Receiver ports cannot belong to the multicast VLAN.
153
Status: Displays the port’s status.
INACTIVE/InVLAN: The port is part of a VLAN but inactive.
INACTIVE/NotInVLAN: The port is not part of any VLAN and
inactive.
ACTIVE/InVLAN: The port is part of a VLAN and active.
Immediate Leave:
Enable or disable the immediate leave function on this port.
When immediate leave is enabled, the receiver port will be
removed for the multicast group when an IGMP leave message
is received on this port, without sending an IGMP qu
ery
message and waiting for the IGMP group membership report.
This function should only be enabled on receiver ports to which
a single receiver device is connected.
9.3.3 Member Config
Use this page to view or configure MVR groups. MVR maintains two types of group entries in its
database, Static and Dynamic. Static entries are configured by the administrator and Dynamic
entries are learned by MVR on the source ports.
Choose the menu Multicast→MVR→Member Config to load the following page.
Figure9-18 MVR Member Config
154
The following entries are displayed on this screen:
Create MVR Group
MVR Group IP: Configure an IP multicast address on the switch
or use the MVR
Group Count parameter to create a contiguous series of MVR
group addresses. Any multicast data sent to this address is sent
to all source ports on the switch and all receiver ports that have
required to receive data on that multicast address.
MVR Group Count:
Specify the number of the contiguous multicast IP group
addresses.
Members:
Statically configure the ports to receive multicast traffic sent to
the multicast VLAN and the IP multicast address specified
above.
Multicast VLAN Registration Group Table
MVR Group IP:
Displays the IP multicast address.
Status:
Displays the status of the multicast group.
Members:
Displays the multicast members in this group.
Operation:
Click Edit to modify this multicast group’s parameters.
9.3.4 Traffic
This page shows statistical information about IGMP packets intercepted by MVR.
Choose the menu Multicast→MVR→Traffic to load the following page.
Figure9-19 MVR Traffic
The following entries are displayed on this screen:
Multicast VLAN Registration Traffic
IGMP Query:
Displays the port number of the switch.
IGMP Report V1:
Displays the number of packets of IGMP Report V1.
IGMP Report V2:
Displays the number of packets of IGMP Report V2.
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IGMP Leave:
Displays the number of packets of IGMP Leave.
IGMP Packet
Failure:
Displays the number of packets of IGMP Packet Failure.
9.4 Multicast Table
You can view different types of multicast table in the follow pages.
9.4.1 Summary
On this page you can view the summary of the multicast table and multicast entries.
Choose the menu Multicast→Multicast Table→Summary to load the following page.
Figure 9-20 Multicast Table
The following entries are displayed on this screen:
Multicast MAC Address Stats
Max MFDB Table
Entries:
Displays the Max MFDB Table Entries.
Most MFDB Entries
Since Last Reset:
Displays the Most MFDB Entries.
Current MFDB
Entries:
Displays the Current MFDB Entries.
Search Option
Select the rules for displaying multicast MAC table to find the desired entries quickly.
All:
Displays all multicast MAC entries.
VLAN ID:
Enter the VLAN ID the desired entry must carry.
MAC Address: Enter the multicast MAC address the desired entry must carry.
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Source:
Enter the source the desired entry must carry.
Type:
Enter the type the desired entry must carry.
Forward Port:
Enter the forward port number the desired entry must carry.
Multicast MAC Address Table
VLAN ID:
Displays the VLAN ID of the multicast MAC entries.
MAC Address:
Displays the MAC address of the multicast MAC entries.
Source:
Displays the source of the multicast MAC entries.
Type:
Displays the type of the multicast MAC entries.
Forward Port:
Displays the forward port of the multicast MAC entries.
9.4.2 Static Config
On this page you can configure the static multicast table. The multicast groups configured here
are not learned by IGMP Snooping and independent of multicast filter.
Choose the menu Multicast→Multicast Table→Static Config to load the following page.
Figure 9-21 Static Multicast Table
157
The following entries are displayed on this screen:
Create Static Multicast
MAC Address:
Enter the multicast MAC address to create multicast MAC entry.
VLAN ID:
Enter the VLAN ID to add multicast MAC entry for the desired
VLAN.
Forward Port:
Select the forward port of multicast MAC entry.
Source Port:
Select the source port of multicast MAC entry.
Search Option
Search Option:
Select the rules for displaying multicast MAC table to find the
desired entries quickly.
• All: Displays all multicast MAC entries.
• VLAN ID: Enter the VLAN ID the desired entry must carry.
• MAC Address: Enter the multicast MAC address the desired
entry must carry.
• Forward Port: Enter the forward port number the desired entry
must carry.
• Source Port: Ent
er the source port number the desired entry
must carry.
Static Multicast MAC Address Table
VLAN ID:
Displays the VLAN ID of the multicast MAC entries.
MAC Address:
Displays the MAC address of the multicast MAC entries.
Type:
Displays the type of the multicast MAC entries.
Forward Port:
Displays the forward port of the multicast MAC entries.
Source Port:
Displays the source port of the multicast MAC entries.
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9.4.3 IGMP Snooping
In an MAC multicast environment, all receivers can join a multicast group. On this page you can
view the information of the multicast groups for IGMP Snooping already on the switch.
Choose the menu Multicast→Multicast Table→IGMP Snooping to load the following page.
Figure 9-22 IGMP Multicast Table
The following entries are displayed on this screen:
Search Option
Search Option: Select the rules for displaying m
ulticast MAC table to find the
desired entries quickly.
• All: Displays all multicast MAC entries.
• VLAN ID: Enter the VLAN ID the desired entry must carry.
• MAC Address: Enter the multicast MAC address the desired
entry must carry.
• Forward Port: En
ter the forward port number the desired entry
must carry.
IGMP Multicast MAC Address Table
VLAN ID:
Displays the VLAN ID of the multicast MAC entries.
MAC Address:
Displays the MAC address of the multicast MAC entries.
Type:
Displays the type of the multicast MAC entries.
Forward Port:
Displays the forward port of the multicast MAC entries.
9.4.4 MLD Snooping
On this page you can view the summary of the multicast table and multicast entries.
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Choose the menu Multicast→Multicast Table→Summary to load the following page.
Figure 9-23 MLD Multicast Table
The following entries are displayed on this screen:
Search Option
Search Option:
Select the rules for displaying multicast MAC table to find the
desired entries quickly.
All: Displays all multicast MAC entries.
• VLAN ID: Enter the VLAN ID the desired entry must carry.
• MAC Address: Enter the multicast MAC address the desired
entry must carry.
• Forward Port: Enter the forward port number the desired entry
must carry.
MLD Multicast MAC Address Table
VLAN ID:
Displays the VLAN ID of the multicast MAC entries.
MAC Address:
Displays the MAC address of the multicast MAC entries.
Type:
Displays the type of the multicast MAC entries.
Forward Port:
Displays the forward port of the multicast MAC entries.
9.4.5 SSM Groups
This page displays information about IGMP snooping and MLD snooping for source specific
multicast.
Choose the menu Multicast→Multicast Table→SSM Groups to load the following page.
Figure 9-24 SSM Group
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The following entries are displayed on this screen:
Search Option
Search Option: Select the rules for displaying source specific
multicast table to
find the desired entries quickly.
All: Displays all source specific multicast entries.
• VLAN ID: Enter the VLAN ID the desired entry must carry.
• Group: Enter the group the desired entry must carry.
• Interface: Enter the interface the desired entry must carry.
• Reporter: Enter the reporter the desired entry must carry.
• Type: Enter the type the desired entry must carry.
• Source Filter Mode: Enter the source filter mode the desired
entry must carry.
• Source Address List: En
ter the source address list the desired
entry must carry.
Source Specific Multicast Groups Table
VLAN ID:
Displays the VLAN ID of the entries.
Group:
Displays the Group of the entries.
Interface:
Displays the Interface of the entries.
Reporter:
Displays the Reporter of the entries.
Type:
Displays the type of the entries.
Source Filter Mode:
Displays the Source Filter Mode of the entries.
Source Address
List:
Displays the Source Address List of the entries.
9.4.6 SSM Entries
This page displays the entries in the multicast forwarding database (MFDB) for source specific
multicast, that were added because they were discovered by the IGMP Snooping or MLD
Snooping feature.
Choose the menu Multicast→Multicast Table→SSM Entries to load the following page.
Figure 9-25 SSM Group Table
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The following entries are displayed on this screen:
Search Option
Search Option:
Select the rules for displaying source specific multicast table to
find the desired entries quickly.
• All: Displays all source specific multicast entries.
• VLAN ID: Enter the VLAN ID the desired entry must carry.
• Group: Enter the group the desired entry must carry.
• Source Ip: Enter the source ip the desired entry must carry.
• Type: Enter the type the desired entry must carry.
• Source Filter Mode: Enter the source filter mode the desired
entry must carry.
• Interface: Enter the interface the desired entry must carry.
Source Specific Multicast Groups Table
VLAN ID:
Displays the VLAN ID of the entries.
Group:
Displays the Group of the entries.
Source IP
Displays the Source IP of the entries.
Type:
Displays the type of the entries.
Source Filter Mode:
Displays the Source Filter Mode of the entries.
Interface:
Displays the Interface of the entries.
9.4.7 SSM Status
This page displays statistics about the source specific multicast forwarding database
(SSMFDB).
Choose the menu Multicast→Multicast Table→SSM Status to load the following page.
Figure 9-26 SSM Status
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The following entries are displayed on this screen:
IGMP Snooping
Total Entries:
Displays the Max MFDB Table Entries.
Most SSM FDB
Entries Ever Used:
Displays the Most SSM FDB Entries Ever Used of source
specific multicast.
Current Entries:
Displays the Current Entries of source specific multicast.
MLD Snooping
Total Entries:
Displays the Max MFDB Table Entries.
Most SSM FDB
Entries Ever Used:
Displays the Most SSM FDB Entries Ever Used of source
specific multicast.
Current Entries:
Displays the Current Entries of source specific multicast.
Return to CONTENTS
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Chapter 10 Routing
Routing is the method by which the host or gateway decides where to send the datagram.
Routing is the task of finding a path from a sender to a desired destination. It may be able to
send the datagram directly to the destination, if that destination is on one of the networks that
are directly connected to the host or gateway. However, what if the destination is not directly
reachable? The host or gateway will attempt to send the datagram to a gateway that is nearer
to the destination. The goal of a routing protocol is very simple: It is to supply the information
that is needed to do routing. This chapter describes how to configure the IPv4 unicast routing
on the T3700G-52TQ.
10.1 Interface
Interface is a virtual interface in Layer 3 mode and mainly used for realizing the Layer 3
connectivity between VLANs or routed ports. Each VLAN interface is corresponding to one
VLAN. Each routed port is corresponding to one port. Loopback Interface is purely software
implemented. Interface has its own IP address and subnet mask to identify the subnet it
belongs to, and it works as the gateway of the subnet to forward Layer 3 IP packets.
Choose the menu Routing → Interface → Interface Config to load the following page.
Figure 10-1 Interface Config
Configuration Procedure:
1) In the Creating Interface section, specify an interface ID and configure relevant parameters
for the interface according to your actual needs. Then click Create.
2) In the Interface List section, you can view the corresponding interface entry you create.
Entry Description:
Create Interface
Interface ID: Enter the ID of the interface corresponding to
VLAN ID,
loopback ID, or routed port.
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IP Address Mode: Specify the IP address assignment mode of the interface.
None: without ip.
Static: setup manually.
DHCP: allocated through DHCP.
IP Address:
Specify the IP address of the interface.
Subnet Mask:
Specify the subnet mask of the interface's IP address.
Admin Status: Enable or disable the interface’s Layer 3 capabilities.
Interface List
Select :
Select the interfaces to modify or delete.
ID:
Displays the ID of the interface.
Mode: Displays IP address allocation mode.
None: without ip.
Static: setup manually.
DHCP: allocated through DHCP.
IP Address:
Displays the IP address of the interface.
Subnet Mask:
Displays the subnet mask of the interface.
Status: Displays interface current working status.
Working status is up
when admin status is enable, line protocol is up and IP Address
is set.
Operation: You can configure the interface by clicking the "Edit
", or check
Detail information by clicking "Detail".
In the Figure 10-1 Interface Config, click Edit to display the following figure:
Figure 10-2 Interface Modify
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Configuration Procedure:
1) In the Modify Interface section, specify an interface ID and configure relevant parameters
for the interface according to your actual needs. Then click Apply.
2) In the Secondary IP Create section, configure the secondary IP for the specified interface
which allows you to have two logical subnets using one physical subnet. Then click Create.
3) In the Secondary IP List section, you can view the corresponding secondary IP entry you
create.
Entry Description:
Interface ID: Displays ID of the interface, including VLAN ID
, loopback
interface and routed port.
IP Address Mode: View and modify the IP address allocation mode.
None: Without IP address.
Static: Setup manually.
DHCP: Allocated through DHCP.
IP Address:
View and modify the IP address of the interface.
Subnet Mask:
View and modify the subnet mask of the interface.
Admin Status: View and modify the Admin status. Choose 'Disable
' to disable
the interface's Layer 3 capabilities.
In the Figure 10-1 Interface Config, click Detail to display the following figure:
Figure 10-3 Detail Information
Detail Information
Interface ID:
Displays ID of the interface, including VLAN ID, loopback
interface and routed port.
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IP Address Mode: Displays the IP address allocation mode.
None: Without IP address.
Static: Setup manually.
DHCP: Allocated through DHCP.
IP Address:
Displays the IP address and subnet mask of the interface.
Secondary IP: Displays the secondary IP address and subnet mask
of the
interface.
Interface Status: Displays the interface curre
nt working status, which is up when
Admin Status is enable, line protocol is up and IP address is set.
Admin Status: Displays the Admin status. Choose 'Disable
' to disable the
interface's Layer 3 capabilities.
Interface Setting Detail Information
Displays the detailed setting information of the interface.
10.2 Routing Table
This page displays the routing information summary generated by different routing protocols.
Choose the menu Routing → Routing Table → Routing Table to load the following page.
Figure 10-4 Routing Table
Routing Information Summary
Protocol
Displays the protocol of the route.
Destination Network:
Displays the destination and subnet of the route.
Next Hop:
Displays the IP address to which the packet should be sent next.
Distance:
Displays the administrative distance which is a rating of the
trustworthiness of a routing information. A higher value means a
lower trust ratin
g. When more than one routing protocols have
routes to the same destination, only the route which has the
smallest distance will be recorded in the IP routing table.
Metric: Displays the metric of the route.
Interface name: Displays the description of the egress interface.
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10.3 Static Routing
Static routes are special routes manually configured by the administrator and cannot change
automatically with the network topology accordingly. Hence, static routes are commonly used
in a relative simple and stable network. Proper configuration of static routes can greatly
improve network performance.
10.3.1 Static Routing
Choose the menu Routing → Static Routing → Static Routing Config to load the following
page.
Figure 10-5 Static Routing Config
Configuration Procedure:
1) In the Static Routing Config section, configure corresponding parameters to add a static
route. Then click Create.
2) In the Static Route Table section, you can view the corresponding interface entry you
create.
Entry Description:
Static Routing Config
Static Route Table
Destination:
Specify the destination IP address of the packets.
Subnet Mask:
Specify the subnet mask of the destination IP address.
Next Hop:
Enter the IP address to which the packet should be sent next.
Distance:
Specify the administrative distance which is a rating of the
trustworthiness of a routing information. A higher value means
a lower trust rating. When more than one routing protocols
have routes to the same destination, only the route which has
the smallest distance will be recorded in the IP routing table.
Select:
Specify the static route entries to modify.
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10.3.2 Application Example for Static Routing
Network Requirements
A small enterprise network is divided into three VLANs: VLAN10, VLAN20 and VLAN30. Their
VLAN IDs are 10, 20 and 30 respectively.
PC1 is in VLAN10 and PC2 is in VLAN30. PC1 and PC2 are reachable for each other.
Network Diagram
Configuration Procedure
Configure Switch A
Steps Operation Note
1
Add interface
VLAN 10
Required. On page Routing→Interface→Interface Config, add
interface VLAN 10 with the mode as static, the IP address as
192.168.0.1, the mask as 255.255.255.0 and the interface name
as VLAN10.
Destination
Address:
Displays the destination IP address of the packets.
Subnet Mask:
Displays the subnet mask of the destination IP address.
Next Hop:
Displays the IP address to which the packet should be sent
next.
Distance: Specify the administrat
ive distance which is a rating of the
trustworthiness of a routing information. A higher value means
a lower trust rating. When more than one routing protocols
have routes to the same destination, only the route which has
the smallest distance will be recorded in the IP routing table.
Metric:
Displays the metric of the route.
Interface Name:
Displays the name of the VLAN interface.
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Steps Operation Note
2
Add interface
VLAN 20
Required. On page Routing→Interface→Interface Config
, add
interfa
ce VLAN 20 with the mode as static, the IP address as
192.168.1.1, the mask as 255.255.255.0 and the interface name
as VLAN20.
3
Add static route
entry
Required. On page Routing→Static Routing→
Static Routing
Config, add a static route entry with the destin
ation as
192.168.2.0, the subnet mask as 255.255.255.0 and the next hop
as 192.168.1.2.
Configure Switch B
Steps Operation Note
1
Add interface
VLAN 20
Required. On page Routing→Interface→Interface Config
, add
interface VLAN 20 with the mode as static, th
e IP address as
192.168.1.2, the mask as 255.255.255.0 and the interface name
as VLAN20.
2
Add interface
VLAN 30
Required. On page Routing→Interface→Interface Config
, add
interface VLAN 30 with the mode as static, the IP address as
192.168.2.1, the mask as 255.255.255.0 and the interface name
as VLAN30.
3
Add static route
entry
Required. On page Routing→Static Routing→
Static Routing
Config
, add a static route entry with the destination as
192.168.0
.0, the subnet mask as 255.255.255.0 and the next hop
as 192.168.1.1.
Configure the PCs
Configure the default gateway of PC1 as 192.168.0.1 and the default gateway of PC2 as
192.168.2.1.
10.4 DHCP Server
DHCP module is used to configure the DHCP functions of the switch, including two submenus,
DHCP Server and DHCP Relay.
Overview
DHCP (Dynamic Host Configuration Protocol) is a network configuration protocol for hosts on
TCP/IP networks, and it provides a framework for distributing configuration information to
hosts. DHCP is adding the capability of automatic allocation of reusable network addresses
and additional configuration options. DHCP captures the behavior of DHCP participants so the
administrator can manage the parameters of the host in the network.
As workstations and personal computers proliferate on the Internet, the administrative
complexity of maintaining a network is increased by an order of magnitude. The assignment of
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local network resources to each client represents one such difficulty. In most environments,
delegating such responsibility to the user is not plausible and, indeed, the solution is to define
the resources in uniform terms, and to automate their assignment.
The DHCP dealt with the issue of assigning an internet address to a client, as well as some
other resources.
DHCP Elements
DHCP is built on a client-server model, where designated DHCP server hosts allocate network
addresses and deliver configuration parameters to DHCP clients. Generally a DHCP server can
allocate configuration parameters to more than one client. Figure 10-6 shows you the model.
Figure 10-6 DHCP model
To meet the different requirements of DHCP clients, DHCP server is always designed to supply
hosts with the configuration parameters in three policies.
1) Manual Assignment: For the specific DHCP clients (e.g., web server), the configuration
parameters are manually specified by the administrator and are assigned to these clients
via a DHCP server.
2) Automatic Assignment: The DHCP server must supplies the configuration parameters to
DHCP client with the lease time continued for ever.
3) Dynamic Assignment: A network administrator assigns a range of IP addresses to DHCP
server, and each client computer on the LAN is configured to request an IP address from
the DHCP server with a fixed period of time (e.g., 2 hours), allowing the DHCP server to
reclaim (and then reallocate) IP addresses that are not renewed.
The Process of DHCP
DHCP uses UDP as its transport protocol. DHCP messages from a client to a server are sent to
the 'DHCP server' port (67), and DHCP messages from a server to a client are sent to the 'DHCP
client' port (68). DHCP clients and servers both construct DHCP messages by filling in fields in
the fixed format section of the message and appending tagged data items in the variable length
option area. The process is shown as follows.
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Figure 10-7 The Process of DHCP
1) DHCP discover: the client broadcasts messages on the physical subnet to discover
available DHCP servers in the LAN. Network administrators can configure a local router (e.g.
a relay agent) to forward DHCP-DISCOVER messages to a DHCP server in a different
subnet.
2) DHCP offer: Each server who received the DHCP-DISCOVER message may respond a
DHCP-OFFER message that includes configuration parameters (in the example below, IP
address) to the client. The server unicast the DHCP-OFFER message to the client (using
the DHCP/BOOTP relay agent if necessary) if possible, or may broadcast the message to a
broadcast address on the client's subnet.
3) DHCP request: A client can receive DHCP offers from multiple servers, but it will accept
only one DHCP-OFFER and broadcast a DHCP-REQUEST message which includes the
server’s identifier and the IP address offered by the server. Based on the server’s identifier,
servers are informed whose offer the client has accepted.
4) DHCP acknowledgement: The server selected in the DHCP-REQUEST message commits
the binding for the client to persistent storage and responds with a DHCP-ACK message
containing the configuration parameters for the requesting client. If the selected server is
unable to satisfy the DHCP-REQUEST message (e.g., the requested IP address has been
allocated), the server should respond with a DHCP-NAK message.
5) In Dynamic assignment policy, the DHCP client is assigned an IP address with a lease time
(e.g. 2 hours) from the DHCP server. This IP address will be reclaimed by the DHCP server
when its lease time expires. If the client wants to use the IP address continually, it should
unicast a DHCP-REQUEST message to the server to extend its lease.
After obtaining parameters via DHCP, a host should be able to exchange packets with any
other host in the networks.
The Format of DHCP Message
Figure 10-6 DHCP model gives the process of DHCP and Figure 10-8 describes each field in
the DHCP message. The numbers in parentheses indicate the size of each field in octets. The
names for the fields given in the figure will be used throughout this document to refer to the
fields in DHCP messages.
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Figure 10-8 The Format of DHCP Message
1) op：Message type, ‘1’ = BOOT-REQUEST, ‘2’ = BOOT-REPLY.
2) htype：Hardware address type, '1' for ethernet.
3) hlen：Hardware address length, '6' for ethernet.
4) hops：Clients set this field to zero and broadcast the DHCP-REQUEST message , optionally
used by relay-agents when booting via a relay-agent.
5) xid：Transaction ID, a random number chosen by the client, used by the client and server to
associate messages.
6) secs：Filled in by client, seconds elapsed since client started trying to boot.
7) flags：A client that cannot receive unicast IP datagrams until its protocol software has been
configured with an IP address should set the first bit in the 'flags' field to 1 in any
DHCP-DISCOVER or DHCP-REQUEST message that client sends. A client that can receive
unicast IP datagrams before its protocol software has been configured should clear the
first bit to 0. A server or relay agent sending or relaying a DHCP message directly to a
DHCP client should examine the first bit in the 'flags' field. If this bit is set to 1, the DHCP
message should be sent as an IP broadcast and if the bit is cleared to 0, the message
should be sent as an IP unicast. The remaining bits of the flags field are reserved for future
use and must be set to zero by clients and ignored by servers and relay agents.
8) ciaddr：Client IP address, filled in by client in DHCPREQUEST when verifying previously
allocated configuration parameters.
9) yiaddr：'your' (client) IP address, configuration parameters allocated to the client by DHCP
server.
10) siaddr：IP address of next server to use in bootstrap, returned in DHCPOFFER, DHCPACK
and DHCPNAK by server.
11) giaddr：Relay agent IP address, used in booting via a relay-agent.
12) chaddr：Client hardware address.
13) sname：Optional server host name, null terminated string.
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14) file：Boot file name, null terminated string, "generic" name or null in DHCPDISCOVER, fully
qualified directory-path name in DHCPOFFER.
15) options：Optional parameters field. See the options documents (RFC 2132) for a list of
defined options. We will introduce some familiar options in the next section.
DHCP Option
This section defines a generalized use of the 'options' field for giving information useful to a
wide class of machines, operating systems and configurations. Sites with a single DHCP server
that is shared among heterogeneous clients may choose to define other, site-specific formats
for the use of the 'options' field. Figure 10-9 gives the format of options field.
Figure 10-9 DHCP Option
All options begin with a Code octet, which uniquely identifies the option followed by the length
octet. The value of the length octet does not include the Code and Length octets. The common
options are illustrated as below.
1) option 1：Subnet Mask option. The subnet mask option is option1 which identifies the
assigned IP address with network, and its length is 4 octets.
2) option 3：Router option. The router option is option 3 which specifies an IP address for
routers on the client's subnet.
3) option 6：DNS option. The DNS option is option 6, and it assigns the IP address of domain
name server to the client which allows the client can use the web service in the internet.
4) option 12：Host Name option. The option12 is used to specify the name of the client, which
may be requested by the DHCP server for authentication.
5) option 50：Requested IP Address option. The option 50 is used in a DHCP-REQUEST
message to allow the client to request the particular IP address.
6) option 51：Lease Time option. In DHCP-OFFER and DHCP-ACK message, the DHCP server
uses this option to specify the lease time in which the clients can use the IP address
legally.
7) option 53：Message Type option. This option is used to convey the type of the DHCP
message. Legal values for this option show in Table 10-1:
Value
Message Type
1
DHCP-DISCOVER
2
DHCP-OFFER
3
DHCP-REQUEST
4
DHCP-DECLINE
5
DHCP-ACK
6
DHCP-NAK
7
DHCP-RELEASE
8
DHCP-INFORM
Table 10-1 Option 53
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8) option 54：Server Identifier option. DHCP servers include option 54 in the DHCP-OFFER
message in order to allow the client to distinguish between lease offers. DHCP clients use
the option in a DHCP-REQUEST message to indicate which lease offers is being accepted.
9) option 55：Parameter Request List option. This option is used by a DHCP client to request
values for specified configuration parameters.
10) option 61：Client hardware address.
11) option 66：TFTP server name option. This option is used to identify a TFTP server.
12) option 67：Boot-file name option. This option is used to identify a boot-file.
13) option 150：TFTP server address option. This option is used to specify the address of the
TFTP server which assigns the boot-file to the client.
For particulars of DHCP option, please refer to RFC 2132. In the next section, DHCP Server and
DHCP Relay function on this switch will be introduced in detail.
Application Environment of DHCP Server
DHCP Server assigns IP address to the client efficiently in the following environment.
1) More and more device proliferates in the network, and it is a hard work to configure the IP
parameter for every device manually.
2) There are not enough network resources to assign to every device exclusively.
3) Only a little device need static IP address to connect the network.
Details of DHCP Server on T3700G-52TQ
A typical application of T3700G-52TQ working at DHCP Server function is shown below. It can
be altered to meet the network requirement.
Figure 10-10 DHCP Server Application
To guarantee the process of assigning IP address fluency and in safety, and to keep the
network run steadily, the DHCP Server function on T3700G-52TQ performs the following tasks.
175
Create different IP pool for every VLAN. The device in different VLAN can get the IP
address in different subnet.
When receiving a DHCP-DISCOVER packet from the client, the switch judges the VLAN
which the ingress port belong to, and chooses the IP in the same subnet with the VLAN
interface to assign to the client.
With a DHCP Relay running between the client and the server, when receiving a
DHCP-DISCOVER packet transmitting from the Relay, the switch will choose the IP from the
IP pool in the same subnet with the Relay’s IP to assign to the client. If the IP pool is not
configured on the switch or the configured IP pool doesn’t match the Relay’s network
segment, the client may not get network parameters successfully.
The switch can detect the IP address automatically before assigning it to avoid conflict.
IP Detection
To avoid IP conflict, the switch will detect the IP address to be assigned in LAN through Ping
test.
The DHCP server will send the Ping test packet with the destination IP being the IP address to
be assigned. If the server receives the Reply packet from the destination host in the ping time,
it means that the IP address has been used, and the server will choose another IP as
destination IP to test again. The server will assign the IP address if the server not receives the
Reply packet in the Ping time.
Policy of IP Assignment
The switch chooses the IP assigned to clients based on the rules shown as follows.
1) First, the server will choose the IP which has been bound to the client manually.
2) Then, the server will assign the IP which has been assigned to the client once.
3) For the next, the server will assign the IP which is specified in the DHCP-DISCOVER packet
from the client.
4) At last, the server will choose the first IP from the IP pool which has not been assigned.
Tips for Configure DHCP Server Function on T3700G-52TQ
1) Configure the Excluded IP address which cannot be assigned by the switch, e.g. web
server’s IP, broadcast IP of subnet and gateway’s IP.
2) Specify IP address for specific clients, and then the switch will supply these IP address to
them only for ever.
3) Configure the IP pool in which the IP address can be assigned to the clients.
The DHCP Server, allowing the clients in all VLANs to get the IP address from the server
automatically, is implemented on the DHCP Server, Pool Setting, DHCP Options Set, Binding
Table and Packet Statistics pages.
10.4.1 DHCP Server
This page allows you to enable the DHCP Server function, configure the Excluded IP Address
which cannot be assigned by the switch in every network.
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Choose the menu Routing→DHCP Server→DHCP Server to load the following page.
Figure10-11 DHCP Server
Configuration Procedure:
1) In the Global Config section, enable or disable DHCP Server and DHCP Conflict-logging.
Then click Apply.
2) In the Ping Time Config section, configure Ping Packets for ping tests. Click Apply.
3) In the Excluded IP Address section, enter the Start IP Address and End IP Address to
specify the range of reserved IP addresses. Click Create.
4) In the Conflict IP Address Table section, you can view the list of the IP addresses that
should not be assigned to DHCP clients for ping conflict checked.
5) In the Excluded IP Address Table section, you can view the list of the IP addresses that
should not be assigned to DHCP clients.
Entry Description:
Global Config
DHCP Server: Enable or disable DHCP Server. By default, it is disabled.
DHCP
Conflict-logging:
Enable or disable DHCP Conflict-
logging. By default, it is
enabled.
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Ping Time Config
Excluded IP Address
10.4.2 Pool Setting
This page shows you how to configure the IP pool in which the IP address can be assigned to
the clients in the network.
Choose the menu Routing→DHCP Server→Pool Setting to load the following page.
Figure 10-12 Pool Setting
Configuration Procedure:
1) Enter the pool name and choose the pool type.
2) Configure the pool parameters according to your actual needs. Click Create.
Entry Description:
Ping Packets:
The number of packets to be sent.
Start IP Address:
The first one of the IP addresses that should not be assigned.
End IP Address:
The last one of the IP addresses that should not be assigned.
Pool Name:
Specify a pool name for identification.
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Pool Type:
Specify the pool type.
IP Address:
Specify the IP address to be bound.
Subnet Mask:
Specify the corresponding subnet mask of the IP address in
the pool.
Binding Mode: Select a binding mode:
Client Id: Bind the IP address to the client ID.
Client Id in ASCii
: Bind the IP address to the client ID in ASCII
format.
Hardware Address: Bind the IP address to the MAC address of
the client.
Client ID:
If you select Client ID as the binding mode, enter the client ID in
this field.
Hardware
Address:
If you select Hardware Address as the binding mode, enter the
MAC address in this field.
Hardware Type:
If you select Hardware Address as the binding mode, select a
hardware type. The hardware type includes Ethernet and
IEEE802.
Lease Time:
Specify the lease time of IP addresses in the pool.
Days:
Specify the days of the lease time of IP addresses in the pool.
Hours:
Specify the hours of the lease time of IP addresses in the pool.
Minutes:
Specify the minutes of the lease time of IP addresses in the
pool.
Default Gateway:
Specify the IP address of the default gateway for a client.
DNS Server:
Specify the IP address of the DNS server for a client.
Netbios Server
：
Specify the NetBIOS name server. You can specify up to 8
NetBIOS servers for each DHCP server pool.
When a DHCP client uses the Network NetBIOS (Basic Input
Output System) protocol for communication, the host name
must be mapped to IP addr
ess. NetBIOS name server can
resolve host names to IP addresses.
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10.4.3 DHCP Options Set
Choose the menu Routing→DHCP Server→DHCP Options Set to load the following page.
Netbios Node Type:
Specify the Netbios type for the clients, which is the way of
inquiring IP address resolution. The following options are
provided:
b-node Broadcast: The client sends query
message via
broadcast.
p-node Peer-to-
Peer: The client sends query message via
unicast.
m-
node Mixed: The client sends query message via broadcast
first. If it fails, the client will try again via unicast.
h-node Hybrid: The client sends query message via unicast
first. If it fails, the client will try again via broadcast.
Next Server
Address:
Specify the IP address of a TFTP server for the clients. If
needed, the clients can get the configuration file from the TFTP
server for auto installation.
Domain Name:
Specify the domain name that the clients should use when
resolving host names via DNS.
Bootfile:
Specify the name of the bootfile. If needed, the clients can get
the bootfile from the TFTP server for auto installation.
option 60: Specify the option
60 for device identification. Mostly it is used
under the scenario where the APs (Access Points) apply for
different IP addresses from different servers according to the
needs.
If an AP requests option 60, the server will respond a packet
containing the o
ption 60 configured here. And then the AP will
compare the received option 60 with its own. If they are the
same, the AP will accept the IP address assigned by the server,
otherwise the assigned IP address will not be accepted.
option 138:
Specify the option 138, which can be configured as the
management IP address of an AC (Access Control) device. If
the APs in the local network request this option, the server will
respond a packet containing this option to inform the APs of
the AC’s IP address.
NTP Server:
Specify the Network Time Protocol Server for a client.
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Figure 10-13 Manual Binding
Configuration Procedure:
1) Select a DHCP server pool from the drop-down list.
2) Configure the extend option in the pool according to your actual needs.
3) Click Create.
Entry Description:
Pool Name:
Select the IP Pool containing the IP address to be bound.
Option Code:
Specify the extend option code.
Option TYPE:
Specify the extend option type.
Option VALUE:
Specify the extend option value.
10.4.4 Binding Table
Choose the menu Routing→DHCP Server→Binding Table to load the following page.
Figure 10-14 DHCP Server Binding Table
Configuration Procedure:
View the information about the clients attached to the server.
Entry Description:
ID:
Displays the ID of the client.
IP Address: Displays the IP address that the s
witch has allocated to the
client.
Client ID / Hardware
Address:
Displays the MAC address of the client.
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Type:
Displays the type of this binding entry.
Lease Time Left(s):
Displays the lease time of the client left.
10.4.5 Packet Statistics
Choose the menu Routing→DHCP Server→Packet Statistics to load the following page.
Figure10-15 Statistics
Configuration Procedure:
View the DHCP packets the switch received or sent.
Entry Description:
Binds
Automatic Bindings:
Displays the DHCP Server auto bindings.
Expired Bindings:
Displays the DHCP Server expired bindings.
Malformed
Bindings:
Displays the DHCP Server malformed binding.
Packets Received
BOOTREQUEST:
Displays the Bootp Request packet received.
DHCPDISCOVER:
Displays the Discover packet received.
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DHCPREQUEST:
Displays the Request packet received.
DHCPDECLINE:
Displays the Decline packet received.
DHCPRELEASE:
Displays the Release packet received.
DHCPINFORM:
Displays the Inform packet received.
Packets Sent
BOOTREPLY:
Displays the Bootp Reply packet sent.
DHCPOFFER:
Displays the Offer packet sent.
DHCPACK:
Displays the Ack packet sent.
DHCPNAK:
Displays the Nak packet sent.
Configuration Procedure (using VLAN interface as an example):
Step
Operation
Description
1
Set the link type for port. Required. On the VLAN→802.1Q VLAN→Port Config page,
set the link type for the port basing on its connected device.
2
Create VLAN. Required. On the VLAN→802.1Q VLAN→VLAN Config
page, click the Create button to create a VLAN. Enter the
VLAN ID and the description for the VLAN. Meanwhile,
specify its member ports.
3
Create VLAN interface. Required. On the Routing→Static Routing→Static Routing
Config page, create the interface IP address of the VLAN.
4
Enable DHCP Server. Required. On the Routing→DHCP Server→DHCP Server
page, enable the DHCP Server function.
5
Configure Excluded IP
Address.
Optional. On the Routing→DHCP Server→DHCP Server
page, configure the Excluded IP Address which cannot be
assigned by the switch.
6
Configure IP Pool. Required. On the Routing→DHCP Server→Pool Setting
page, configure the parameters of IP Pool.
10.4.6 Application Example for DHCP Server and Relay
Network Requirements
Every building in the campus belongs to separate VLANs with different network segments.
The access points in each building are divided into two parts. One part is the fixed
computers with static IP addresses in the teachers’ offices; the other is the classroom, in
which most clients are laptops with dynamic IP addresses obtained from the DHCP server.
DNS Server is in VLAN 1 and its IP address is 160.20.30.2.
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Network Diagram
Use T3700G-52TQ as the central switch and enable its DHCP server function to allocate IP
addresses to clients in the network. Enable the DHCP relay function on each access switch in
VLAN 10, 20 and 30. For details about DHCP relay, please refer to 10.5 DHCP Relay.
Configuration Procedure
Configure Central Switch
Step Operation Note
1
Create VLAN Required. On page VLAN→802.1Q VLAN→VLAN Config, create
VLAN10, VLAN20 and VLAN30, and configure their ports.
2
Create VLAN
interface
Required. On page Routing→Interface→Interface Config,
configure VLAN interface
192.168.10.1/24 for VLAN10,
192.168.20.1/24 for VLAN20, and 192.168.30.1 for VLAN30.
3
Enable DHCP
Server
Required. On page Routing→DHCP Server→DHCP Server,
enable DHCP Server function under the Global Config.
4
Configure the IP
address pool
Required. On page Routing→DHCP Server→Pool Setting,
configure IP address pool parameters for each VLAN interface.
Take VLAN10 as an example, configure its Network Address as
192.168.10.0, Subnet Mask as 255.255.255.0, Default gateway as
192.168.10.1 (the IP address of the VLAN interface), DNS Server
as 160.20.30.2,customize the Pool Name, Lease Time and other
parameters.
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Step Operation Note
5
Configure the
reserved
addresses
Required. On page Routing→DHCP Server→DHCP Server, under
the Excluded IP Address, configure reserved IP addresses for the
fixed computers in each VLAN.
Configure Access Switch
Step
Operation
Note
1 Enable DHCP
Relay.
Required. On the Routing→DHCP Server→Global Config page,
enable the DHCP Server function, and the DHCP Relay function
will be enabled at the same time.
2 Configure Option
82 support.
Optional. On the Routing→DHCP Relay→Global Config page,
configure the Option 82 parameters.
3 Configure DHCP
Server.
Required. On the Routing→DHCP Relay→DHCP Server page,
specify the DHCP Server with the IP address of the central switch.
10.5 DHCP Relay
Application Environment of DHCP Relay
In DHCP model, DHCP clients broadcast its DHCP request, so the DHCP sever and clients must
be on the same subnet, which require the DHCP server is available in every subnet. It is costly
to build so much DHCP Server. DHCP relay agent solves the problem. Via a relay agent, DHCP
clients request an IP address from the DHCP server in another subnet, and DHCP clients in
different subnets can share the same DHCP server in the internet.
Details of DHCP Relay on T3700G-52TQ
A typical application of T3700G-52TQ working at DHCP Relay function is shown below. It can
be altered to meet the network requirement.
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Figure 10-16 DHCP Relay Application
To allow all clients in different VLAN request IP address from one server successfully, the
DHCP Relay function can transmit the DHCP packet between clients and server in different
VLANs, and all clients in different VLANs can share one DHCP Server.
When receiving DHCP-DISCOVER and DHCP-REQUEST packets, the switch will fill the
giaddr field with the interface IP of the receiving port, optionally insert the option 82
information, and then forward the packet to the server.
When receiving DHCP-OFFER and DHCP-REQUEST packets from the server, the switch will
delete the option 82 information and forward the packet to the interface which receives the
request.
The process will be shown as follows.
Figure 10-17 DHCP Relay Process
DHCP Relay Configuration
1) Configure the Option 82 parameters to record the information of the clients. You are
suggested to configure the option82 on the nearest Relay of the client.
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2) Specify the DHCP Server which assigns IP addresses actually.
Option 82
On this switch, Option 82 is used to record the location of the DHCP Client, the ethernet port
and the VLAN, etc. Upon receiving the DHCP-REQUEST packet, the switch adds the Option 82
field to the packet and then transmits the packet to DHCP Server. The Server can be
acquainted with the location of the DHCP Client via Option 82, so as to locate the DHCP Client,
and assign the distribution policy of IP addresses and the other parameters for fulfilling the
security control and account management of the client.
Option 82 can contain 255 sub-options at most. If Option 82 is defined, at least one sub-option
should be defined. This Switch supports two sub-options, Circuit ID and Remote ID. Since there
is no universal standard about the content of Option 82, different manufacturers define the
sub-options of Option 82 to their need. For this Switch, the sub-options are defined as follows:
The Circuit ID is defined to be the number and VLAN of the port which receives the DHCP
Request packets. The Remote ID is defined to be the MAC address of DHCP Relay device which
receives the DHCP Request packets from DHCP Clients. Furthermore these two parameters
also can be manually configured.
The format of Option 82 defined on the switch by default is given in the following figure. The
numbers in parentheses indicate the size of each field in octets. By default, sub-option1 is
Circuit ID option recording the VLAN and ethernet port information, while sub-option2 is
Remote ID option recording the MAC address information of the client. You can define the
sub-options manually.
Figure10-18 Option 82
Note:
The option 82 parameters configured on the switch should base on and meet the requirement
of the network.
The DHCP Relay, allowing the clients to get the IP address from the server in another subnet, is
implemented on the DHCP Relay page. When the DHCP Server is enabled, the DHCP Relay will
be enabled too.
10.5.1 Global Config
This page allows you to enable the DHCP Relay function.
187
Choose the menu Routing→DHCP Relay→Global Config to load the following page.
Figure 10-19 Global Config
Configuration Procedure:
1) In the Global Config section, enable DHCP Relay.
2) (Optional) In the Option 82 Configuration section, configure Option 82.
3) Click Apply.
Entry Description:
DHCP Relay:
Enable or disable DHCP Relay.
Option 82 Support:
Select whether to enable Option 82 or not. By default, it is
disab
led. Option 82 is used to record the locations of the
DHCP client, its Ethernet port and the VLAN, etc. If you need
to record the accurate location of a client, you can enable
Option 82 on the relay device closest to the client.
Existed Option 82
Field: S
elect the operation for the Option 82 field of the DHCP
request packets.
Keep: Indicates keeping the Option 82 field of the packets.
Replace:
Indicates replacing the Option 82 field of the
packets with the switch defined one. By default, the Circuit
ID is
defined to be the VLAN and the number of the port
which receives the DHCP Request packets. The Remote ID
is defined to be the MAC address of the DHCP Relay device
which receives the DHCP Request packets.
Drop: Indicates discarding the packets that include
the
Option 82 field.
Circuit ID:
Enter the customized circuit ID, which contains up to 32
characters. The circuit ID configurations of the switch and
the DHCP server should be compatible with each other.
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Remote ID: Enter the customized remote ID, which
contains up to 32
characters. The remote ID configurations of the switch and
the DHCP server should be compatible with each other.
10.5.2 DHCP Server
This page enables you to configure DHCP Servers on the specified interface.
Choose the menu Routing→DHCP Relay→DHCP Server to load the following page.
Figure 10-20 DHCP Server
Configuration Procedure:
1) In the Add DHCP Server Address section, select the interface type and enter the interface
ID, and then enter the server address of the interface.
2) Click Create to specify the DHCP server for the interface.
Entry Description:
Add DHCP Server Address
Interface ID:
Select the interface type and enter the interface ID.
Server Address:
Enter the DHCP server IP address.
DHCP Server List
Select:
Select the desire DHCP server item.
Interface ID:
Displays the interface ID.
Server Address:
Displays the DHCP server address.
Configuration Procedure:
Step
Operation
Description
1
Enable DHCP Relay. Required. On the Routing→DHCP Relay→Global Config
page, enable DHCP Relay function.
2
Configure
Option 82
support.
Optional. On the Routing→DHCP Relay→Global Config
page, configure the Option 82 parameters.
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Step
Operation
Description
3
Configure DHCP Server. Required. On the Routing→DHCP Relay→DHCP Server
page, specify the DHCP Server with IP address.
10.6 Proxy ARP
Proxy ARP functions to realize the Layer 3 connectivity between the hosts within the same
network segment but isolated at Layer 2.
When an ARP request of a host is to be forwarded to another host in the same network
segment but isolated at Layer 2, to realize the connectivity, the device connecting the two
virtual networks should be able to respond to this request. This can be achieved by the device
running proxy ARP.
Within the same network segment, hosts connecting with different layer 3 ports can
communicate with each other through Layer 3 forwarding by using proxy ARP function. The
following example simply illustrates how proxy ARP works.
Figure 10-21 ARP Application
Within the same network segment, hosts connecting with the same layer 3 port can
communicate with each other through Layer 3 forwarding by using local proxy ARP function.
The following example simply illustrates how local proxy ARP works.
Figure 10-22 Local ARP Application
10.6.1 Proxy ARP
On this page you can enable Proxy ARP function for the layer 3 port.
190
Choose the menu Routing→Proxy ARP→Proxy ARP to load the following page.
Figure 10-23 Proxy ARP
Configuration Procedure:
Enable Proxy ARP for the VLAN interface or routed port.
Entry Description:
IP Address/
Subnet
Mask:
Displays the IP Address and S
ubnet Mask of the VLAN
interface or routed port.
Interface:
Displays the VLAN interface ID of the VLAN interface or the
port number of the routed port.
Status:
Enable or disable Proxy ARP.
10.6.2 Local Proxy ARP
On this page you can enable Local Proxy ARP function for the layer 3 port.
Choose the menu Routing→Proxy ARP→Local Proxy ARP to load the following page.
Figure 10-24 Proxy ARP
Configuration Procedure:
Enable Local Proxy ARP for the VLAN interface or routed port.
Entry Description:
IP Addres
s/ Subnet
Mask:
Displays the IP Address and Subnet Mask of the VLAN
interface or routed port.
Interface:
Displays the VLAN interface ID of the VLAN interface or the
port number of the routed port.
Status:
Enable or disable Local Proxy ARP.
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10.6.3 Application Example for Proxy ARP
Network Requirements
1. PC A and PC B are in the same network segment but belong to VLAN2 and VLAN3
respectively.
2. The IP address of PC A is 192.168.2.10/16 and the IP address of PC B is 192.168.3.11/16.
3. PC A and PC B can interconnect with each other by using Proxy ARP function.
Network Diagram
Configuration Procedure
Configure the Switch
Step
Operation
Description
1
Create VLAN Required. On page VLAN→802.1Q VLAN→VLAN Config
, create
VLAN 2 and VLAN 3, and configure their ports.
2
Create VLAN
Interface 2
Required. On Routing→Interface→Interface Config
page, create
VLAN Interface 2 with its IP address as 192.168.2.1, subnet mask as
255.255.255.0 and interface name as VLAN2.
3
Create VLAN
Interface 3
Required. On Routing→Interface→Interface Config
page, create
VLAN Interface 3 with its IP address as 192.168.3.1, subnet mask as
255.255.255.0 and interface name as VLAN3.
4
Enable Proxy
ARP
Required. On Routing→Proxy ARP→Proxy ARP page, enable Proxy
ARP feature for VLAN interface 2 and VLAN interface 3.
10.7 ARP
This page displays the ARP table information and you can configure static ARP here.
10.7.1 ARP Table
Choose the menu Routing → ARP → ARP Table to load the following page.
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Figure 10-25 ARP Table
Configuration Procedure:
View all the dynamic and static ARP entries.
Entry Description:
Interface:
Displays the network interface of an ARP entry.
IP Address:
Displays the IP address of an ARP entry.
MAC Address:
Displays the MAC address of an ARP entry.
Type: Displays the type of an ARP entry.
STATIC: A static ARP entry that will always be remained.
DYNAMIC:
A dynamic ARP entry that will be deleted after
aging time.
10.7.2 Static ARP
You can add desired static ARP entries by mannually specifying the IP addresses and MAC
addresses.
Choose the menu Routing → ARP → Static ARP to load the following page.
Figure 10-26 Static ARP
Configuration Procedure:
In the ARP Config section, enter the IP address and MAC address and click Create.
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Entry Description:
ARP Config
IP Address:
Specify the IP address of an ARP entry.
MAC Address:
Specify the MAC address of an ARP entry.
ARP Table
Select:
Specify the static ARP entries to modify.
IP Address:
Displays the IP address of an ARP entry.
MAC Address:
Displays the MAC address of an ARP entry.
10.8 RIP
Note
：
Router mentioned in this chapter refers to the traditional router or the switch running routing
protocols.
RIP (Routing Information Protocol) is intended for use within the IP-based Internet. This
protocol is most useful as an Interior Gateway Protocol (IGP). RIP was designed to work with
moderate-size networks using reasonably homogeneous technology. Thus it is suitable as an
IGP for many campuses and for regional networks using serial lines whose speeds do not vary
widely. It is not intended for use in more complex environments.
RIP is a distance vector routing protocol, using UDP packets for exchanging information
through port 520.
RIP uses “hop” to measure the distance to a destination. The hop count from a router to a
directly connected network is 0. The hop count from a router to a directly connected router is 1.
To limit convergence time, the range of RIP metric value is from 0 to 15. A metric value of 16 (or
greater) is considered infinite, which means the destination network is unreachable. That is why
RIP is not suitable for large-scaled networks.
RIP prevents routing loops by implementing the split horizon and poison reverse functions.
RIP routing table
An RIP router has a routing table containing routing entries of all reachable destinations, and
each routing entry contains:
Destination address: IP address of a host or a network.
Next hop: IP address of the adjacent router’s interface to reach the destination.
Egress interface: Packet outgoing interface.
Metric: Cost from the local router to the destination.
Route time: Time elapsed since the routing entry was last updated. The time is reset to
0 every time the routing entry is updated.
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RIP timers
RIP employs three timers: update, timeout and garbage-collect.
Update timer: defines the interval between routing updates.
Timeout timer: defines the route aging time. If no update for a route is received within
the aging time, the metric of the route is set to 16 in the routing table.
Garbage-collect: timer defines the interval from when the metric of a route becomes
16 to when it is deleted from the routing table. During the garbage-collect timer length,
RIP advertises the route with the routing metric set to 16. If no update is announced
for that route after the garbage-collect timer expires, the route will be deleted from the
routing table.
Routing loops prevention
RIP is a distance vector (D-V) routing protocol. Since an RIP router advertises its own routing
table to neighbors, routing loops may occur.
RIP uses the following mechanisms to prevent routing loops.
Counting to infinity: The metric value of 16 is defined as unreachable. When a routing
loop occurs, the metric value of the route will increment to 16.
Split horizon: A router does not send the routing information learned from a neighbor
to this neighbor to prevent routing loops and save bandwidth.
Poison reverse: A router sets the metric of routes received from a neighbor to 16 and
sends back these routes to the neighbor to help delete such information from the
neighbor’s routing table.
Triggered updates: A router advertises updates once the metric of a route is changed
rather than after the update period expires to speed up network convergence.
Operation of RIP
The following procedure describes how RIP works.
1) After RIP is enabled, the router sends request messages to neighboring routers.
Neighboring routers return Response messages including information about their routing
tables.
2) After receiving such information, the router updates its local routing table, and sends
triggered update messages to its neighbors. All routers on the network do the same to
keep the latest routing information.
3) By default, an RIP router sends its routing table to neighbors every 30 seconds.
4) RIP ages out routes by adopting an aging mechanism to keep only valid routes.
RIP Version
RIP has two versions, RIPv1 and RIPv2.
RIPv1, a classful routing protocol, supports message advertisement via broadcast only. RIPv1
protocol messages do not carry mask information, which means it can only recognize routing
information of natural networks such as Class A, B, and C. That is why RIPv1 does not support
discontinuous subnets.
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RIPv2 is a classless routing protocol. Compared with RIPv1, RIPv2 has the following
advantages.
Supporting route tags. Route tags are used in routing policies to flexibly control
routes.
Supporting masks, route summarization and Classless Inter-Domain Routing (CIDR).
Supporting designated next hops to select the best next hops on broadcast networks.
Supporting multicast routing update to reduce resource consumption.
Supporting plain text authentication and MD5 authentication to enhance security.
Note
：
RIPv2 has two types of message transmission: broadcast and multicast. Multicast is the default
type using 224.0.0.9 as the multicast address. The interface working in the RIPv2 broadcast
mode can also receive RIPv1 messages.
RIP Message Format
1) RIPv1 message format
A RIPv1 message consists of a header and up to 25 route entries. The following figure shows
the format of RIPv1 message.
Figure 10-27 RIPv1 Message Format
The detailed explanations of each field are stated as following:
Command: Type of message. 1 indicates request, and 2 indicates response.
Version: Version of RIP, 0x01 for RIPv1.
AFI: Address Family Identifier, 2 for IP.
IP Address: Destination IP address of the route. It can be a natural network, subnet or a
host address.
Metric: Cost of the route.
2) RIPv2 message format
The format of RIPv2 message is shown as the following figure. It is similar to RIPv1.
196
Figure 10-28 RIPv2 Message Format
The detailed explanations of each field are stated as following:
Version: Version of RIP. For RIPv2 the value is 0x02.
Route Tag: Route Tag.
IP Address: Destination IP address. It can be a natural network address, subnet
address or host address.
Subnet Mask: Mask of the destination address.
Next Hop: If set to be 0.0.0.0, it indicates that the originator of the route is the best
next hop; otherwise it indicates a next hop better than the originator of the route.
RIPv2 authentication
RIPv2 sets the AFI field of the first route entry as 0xFFFF to identify authentication information.
See Figure 10-26.
Figure 10-29 RIPv2 Authentication Message
Authentication Type: A value of 2 represents plain text authentication, while a value of
3 indicates MD5 authentication.
Authentication: Authentication data, including password information when plain text
authentication is adopted or including key ID, MD5 authentication data length and
sequence number when MD5 authentication is adopted.
Note
：
RFC 1723 only defines plain text authentication. For more information about MD5
authentication, please see RFC 2453 RIP Version 2.
This function includes three submenus: Basic Config, Interface Config and RIP Database.
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10.8.1 Basic Config
RIP (Routing Information Protocol) is a dynamic router protocol with Distance Vector
Algorithms. You could configure the protocol below to active as you like.
Choose the menu Routing→RIP→Basic Config to load the following page.
Figure 10-30 RIP Basic Config
The following entries are displayed on this screen:
RIP Enable
RIP Protocol: Choose to enable or disable the RIP function. By
default it is
enable.
198
Global Config
RIP Version: Choose the global RIP version.
Default: send with RIP version 1 and receive with both
RIP version 1 and 2.
RIPv1:
send and receive RIP version 1 formatted
packets via broadcast.
RIPv2: send and receive
RIP version 2 packets using
multicast.
Split Horizon Mode: Choose the Split Horizon Mode.
None: no special processing for this case.
split-horizon: a route will not be included in updates sent
to the router from which it was learned.
Poison Reverse: a route will be included in updates sent
to the router from which it was learned, but the metric
will be set to infinity.
RIP Distance:
Set the RIP router distance.
Auto Summary:
If you select enable groups of adjacent routes will be
summarized into single en
tries, in order to reduce the total
number of entries The default is disable.
Default Metric:
Set the default metric for the redistributed routes. The valid
values are (1 to 15).
Redistribute Static: Choose to distribute Static router entries to RIP, the
default
is disable.
Redistribute OSPF: Choose to distribute OSPF router entries to RIP,
the default
is disable.
Redistribute Static
Metric:
Set the metric of redistributed Static routes. The valid values
are (0 to 15).
Redistribute OSPF
Metric:
Redistribute OSPF Metric. Set the metric of redistributed
OSPF routes. The valid values are (0 to 15).
Update Timer: T
he timer interval to generate a complete response to every
neighboring gateway.
Timeout Timer: Upon expiration of the timeout, the route is no
longer valid
and set to unreachable.
Garbage Timer: Upon expiration of the garbage-
collection timer, the route is
finally removed from the tables.
Network Enable
You could add the network to enable RIP protocol here, so the interface in the network would
enable RIP protocol.
RIP Network List
Display the network enabled in the list. You could choose to delete the network here.
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10.8.2 Interface Config
On this page, you can configure advanced parameters for the RIP.
Choose the menu Routing→RIP→Interface Config to load the following page.
Figure 10-31 RIP Interface Config
The following entries are displayed on this screen:
Interface Config
Select:
Select the interface for which data is to be configured.
Interface：
Displays the Interface ID.
IP Address:
The interface IP address. You cannot change it here.
Status: The interface RIP status (up or down) is decided
by the
network status. You cannot change it here.
Send Version: Select t
he version of RIP control packets the interface
should send from the pulldown menu.
RIPv1:
send RIP version 1 formatted packets via
broadcast.
RIPv2: send RIP version 2 packets using multicast.
RIP-1c: send RIP version 2 packets using broadcast.
Receive Version:
Select what RIP control packets the interface will accept
from the pulldown menu.
RIPv1: accept only RIP version 1 formatted packets.
RIPv2: accept only RIP version 2 formatted packets.
Both:
accept both RIP version 1 and RIP version 2
formatted packets.
Authen Mode: Select an authentication type.
None
: This is the initial interface state. If you select this
option from the pulldown menu no authentication
protocols will be run
Simple
: If you select 'Simple' you will be prompted to
enter an authent
ication key. This key will be included, in
the clear, in the RIP header of all packets sent on the
network. All routers on the network must be configured
with the same key.
MD5:
If you select 'MD5' you will be prompted to enter
both an authentication key a
nd an authentication ID. All
routers on the network must be configured with the same
key and ID.
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Key ID:
Enter the RIP Authentication Key ID for the specified
interface. If you choose not to use authentication or to use
'simple' you will not be prompted to enter the key ID.
Key:
Enter the RIP Authentication Key for the specified interface.
If you do not choose to use authentication you will not be
prompted to enter a key. If you choose 'simple' or 'MD5' the
key may be up to 16 octets long.
10.8.3 Application Example for RIP
Network Requirements
IP addresses of Switch A's three interfaces are 1.1.1.1/24, 2.1.1.1/24, 3.1.1.1/24 respectively.
IP addresses of Switch B's three interfaces are 1.1.1.2/24, 10.1.1.1/24, 11.1.1.1/24
respectively.
RIP is required to be enabled in all interfaces of Switch A and B. Network shall be
interconnected between Switch A and B with the use of RIPv2.
Network Diagram
Configuration Procedure
Configure Switch A
Step Operation Note
1
Enable RIP Required. On page Routing→RIP→Basic Config
, enable RIP,
select RIPv2 as RIP version.
2
Enable the network
segments where
the interfaces are
located
Required. On page Routing→RIP→Basic Config Network Enable
part, add network segments 1.1.1.0, 2.1.1.0, 3.1.1.0, and enable
RIP in these network segments. These network segments will be
displayed in RIP Network List after they are successfully added.
Configure Switch B
Step Operation Note
1
Enable RIP Required. On page Routing→RIP→Basic Config
, enable RIP,
select RIPv2 as RIP version.
2
Enable the network
segments where
the interfaces are
located
Required. On page Routing→RIP→Basic Config Network Enable
part, add network segments 1.1.1.0, 10.1.1.0, 11.1.1.0, and enable
RIP in these network segments. These network segments will be
displayed in RIP Network List after they are successfully added.
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10.9 OSPF
OSPF (Open Shortest Path First) is a routing protocol based on link state and also an internal
gateway protocol, which is developed and recommended by IETF. The OSPF protocol standard
in current use for IPv4 network is OSPF Version 2, which is defined specifically in RFC2328 and
will be introduced generally in this Guide.
Introduction
1. OSPF Features
OSPF protocol is a popular routing protocol in networking with the following features.
Fast convergence – It could send update packets immediately upon the change of network
topology, to quickly synchronize the update for the routers in the autonomous system.
Due to the rapid convergence, OSPF routing protocol acts with great speediness and
stability in the large-scale network, and is not prone to some harmful routing information.
OSPF protocol introduces the concept of area – to manage the autonomous system by
area, which means the routers only need to synchronize the link state database with the
other routers in the same area. Thus, the smaller link state database requires lower
memory consumption from the routers, and the less routing information to manage also
releases certain CPU resources for the routers and meanwhile reduces the network
bandwidth occupied by the routing information.
OSPF protocol supports multiple equal-cost routes to one destination for load balance,
thus to perform more efficient data forwarding.
OSPF supports VLSM route addressing by variable-length subnet mask.
OSPF supports the message authentication based on interfaces, thus to guarantee the
security of message interaction and routing calculation.
OSPF supports using the reserved multicast address in the link of specific network type, to
reduce the influence on the other irrelevant routers.
2. OSPF Common Scenario
OSPF protocol is usually applied in the large complex network environment. Shown as below is
the instance diagram of a large company, where the large network is divided by department.
OSPF protocol works as the fundamental routing protocol among routers, which could
guarantee not only the message interaction but also the network independence among
departments.
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Figure 10-32 Common Scenario for OSPF routing protocol
The network topology is more prone to changes in an autonomous system of larger size. The
network adjustment of any one router could destabilize the whole network and cause massive
OSPF packets to be forward repeatedly, and all the routers need to recalculate the routes,
which would waste lots of network resources. In this case, area partition would be an effective
solution. The routers only need to maintain the same link state database in their own area, and
then the ABR would collect the routing information from different areas and advertise to other
areas. For more details about area partition, please refer to the following chapters.
OSPF Principles
This section would introduce in details the working principles of OSPF protocol. First of all, let’s
get to know some basic concepts about the OSPF routing protocol.
1. Autonomous System
Autonomous System, short for AS, is a set of routers using the same routing protocol to
exchange routing information. OSPF, working within an AS, is an internal gateway protocol.
2. Router ID
A router running OSPF protocol identifies its uniqueness by its router ID – a 32-bit unsigned
integer, which could be manually assigned by the administrator or automatically selected by
the router itself. In case different routers might obtain the same ID in automatic selection, you
are recommended to configure router ID manually.
In RFC protocol, two means of automatically electing router ID are recommended:
If the loopback interfaces are configured, the highest IP address among them will be
selected as the router ID.
If no loopback interface is configured, the highest IP address among those of active router
interfaces will be selected as the router ID.
The good stability of loopback interfaces (always in active state as long as the router boots)
ensures that every time the router boots it would automatically elect the loopback interface IP
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address as the router ID which is thus always invariant outward. To ensure the uniqueness of
the router ID, it is recommended to manually configure the router ID or the loopback interface.
In the automatic election, the router would in the first place select the highest loopback interface
IP address as the router ID. If the router doesn’t pre-define the loopback interfaces, it would
select the highest physical interface IP address as the router ID.
3. OSPF Network Types
OSPF, a dynamic routing protocol running in the network layer, would apply different working
mechanism according to the features of different data link layers. There are four sorts of
relationships between the working mechanism of OSPF routing protocol and network type.
1) Broadcast: When the network type is Ethernet or FDDI, OSPF protocol would broadcast
the Hello, LSU and LSAck packets. For instance, the Hello packet is multicast to the other
OSPF routers in the LAN and the destination address is the reserved 224.0.0.5, while the
other routers forward the link state update and acknowledgement data to OSPF DR with
the reserved multicast address as 224.0.0.6. In such broadcast type of network the DD and
LSR packets are unicast.
2) NBMA (Non-Broadcast Multi-Access): In such type of network as frame relay, ATM or X.25,
where the routers need extra configuration to find neighbors, the OSPF protocol packets
are unicast.
3) P2MP (Point-to-MultiPoint): In general, P2MP type of network is converted from NBMA,
where the Hello packet is multicast (224.0.0.5), LSU and LSAck packets are multicast
(224.0.0.5) or unicast, DD and LSR packets are unicast.
4) P2P (Point-to-Point): When the link layer protocol is PPP or HDLC, the link always
connects a pair of routers, who could generally establish an adjacency relationship after
becoming valid neighbors. In this type of network, the protocol packets are multicast
(224.0.0.5).
Our switches are all Ethernet ones. The network type of all the interfaces defaults to Broadcast,
and it also supports to be configured as P2P type that can automatically find neighbors. To
ensure the communication of multi-point networking, it’s not recommended to manually
configure the network type of interfaces. In the following guide, we will mainly take the
broadcast type of interface for example to introduce the working principle of OSPF protocol.
4. Designated Router and Backup Designated Router
On broadcast networks or NBMA networks, usually there are multiple routers running OSPF
protocol at the same time. If the neighbor relationship between any two routers is adjacency,
the change of one router could result in the repeated forwarding of route updates and a waste
of network resources.
DR (Designated Router) and BDR (Backup Designated Router) defined by OSPF protocol would
maintain the entire network, while the other routers only need to establish adjacency
relationships with DR and BDR. DR is responsible to flood the routing information in the network
to all the neighbors. When DR fails, BDR will become the new DR, which avoids network block
during the DR re-election. Then a new BDR needs to be re-elected for sure, but the process
would not affect the communication even though it still requires quite a long time. Once DR and
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BDR are determined in a network, unless they become invalid, any new routers joining or exiting
would not cause re-election.
As shown below, on a network of five routers, ten adjacency relations need to be established if
one between every two routers, but only seven adjacencies are required if DR and BDR are
introduced. To conclude, on a network of N routers, N*(N-1)/2 adjacencies are required in
general, but the adjacencies required will be (N-2)*2+1 if DR and BDR are introduced. Therefore,
the more routers on the network, the more significant the advantages will be.
Figure 10-33 Diagram of DR/BDR Adjacency Relation
DR or BDR is determined by the interface priority and router ID. First of all, whether a router
could be the DR or BDR on a network is decided by its interface priority. The one of highest
priority would be elected as DR or BDR; while if all the interfaces are of the same priority, it
would then be decided by the router ID. In conclusion, DR or BDR is the feature of a certain
interface of the router which indicates the status of the router in a network segment rather than
the features of the router on the network. Every network segment needs to elect a DR and a
BDR to synchronize the routing information. The configuration of router interface parameters
needs to be done on the basis of network planning.
OSPF Working Process
In the following, we would take the example of two routers initiating interface OSPF protocol to
introduce the working process of OSPF routing protocol in the Ethernet model.
1) The router interface initiates the OSPF protocol, and then the interfaces in the same
network segment would discover neighbors by sending Hello packets. If the interfaces are
connected on the same public data link, and the area IDs, authentication information,
network subnet, Hello data interval and neighbor router dead-interval are all matched, the
two routers would put each other in its neighbor table.
2) If the receiver discovers its own ID on the neighbor table of the Hello packet, a successful
mutual communication would be established. And then they will elect DR and BDR
according to such parameters as the interface priority and the router ID, while if DR and
BDR already exist in the network, they will be accepted.
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3) After DR and BDR are determined, the master and slave one will be elected between the
DR/BDR and the other routers on the network, and then the link state database
synchronization will start.
4) On the network the routers and DR/BDR will mutually unicast the link state data to
advertise LSA, until all the routers establish an identical link state database. During the
synchronization of link state database, if the database description packet sent contains an
updated LSA or a LSA the receiver doesn’t have, the receiver would send request for the
details of this LSA via LSR packets. In other words, in any phase of DD exchange, as long
as the received DD packet contains new LSA information, the receiver could send LSA
request for synchronization. The routers receiving the LSR packet will unicast the LSU
packet carrying LSA to the other end.
5) After two routers have finished the synchronization of link state database, a complete
adjacency relation will be established.
6) When the intra-area routers have an identical link state database, each of them will
calculate a loop-free topology through SPF algorithm with itself as the root thus to
describe the shortest forward path to every network node it knows, and create a routing
table according to the topology of shortest forward path and provide a basis for data
forwarding.
7) After the establishment of routing table, if the network remains stable, the neighbors would
discover and maintain their neighbor relationships by sending out Hello packets at regular
intervals. And the adjacent routers would recalculate the routing table by periodical LSA
update in order to maintain valid entries in the routing table.
8) Any new routers joining the network will accept the current DR/BDR and synchronize the
link state database with them until a complete adjacency relation is established. During
synchronizing the link state database, DR/BDR will obtain LSA from the newly-joint routers
and then flood this LSA to the adjacent routers who then will flood it to the other ports till
the entire network.
1. Work Flow Diagram
The diagram below takes two routers for example to introduce in the Ethernet module the
detailed steps of two routers from failure state to complete adjacency state and the relevant
packet types involved in the process.
Note:
To facilitate the description the diagram below shows the LSA synchronization after the DD
exchange, while in reality these two processes are simultaneous.
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Figure 10-34 Steps to Establish a Complete Adjacency Relation
2. Flooding
As Figure 10-32 shows, two random routers will synchronize the link state database via LSA
request, LSA update and LSA acknowledgement packets. But in the actual module of router
network, how do the routers flood the change of local network to the entire network through
LSA update packets? Figure 10-33 will introduce in details the flooding of the LSA update
packets on the broadcast network.
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Figure 10-35 Flooding of the LSA
1) DROthers multicast the LSA update of its directly-connected network to DR and BDR.
2) After receiving the LSA update, DR floods it to all the adjacent routers.
3) After receiving the LSA update from DR, the adjacent routers flood it to the other OSPF
interfaces in their own areas.
Area and Route Summarization
OSPF protocol gets every router in the network to obtain a complete network topology through
adjacency relationship, thus to calculate the routing table and accomplish the forwarding of
network data. As the network grows in size, every router has to spend plenty of resources to
store LSDB and calculate routing table, so any delicate changes in the network topology will
require the routers in the entire network to re-synchronize and re-calculate, which will cause
the network to be in the state of frequent “oscillation”.
In order to run effectively and efficiently in a large-scale network, OSPF protocol can divide the
routers in an autonomous system into logic areas identified by Area ID. After the area partition,
the intra-area routers will accomplish the route addressing and data forwarding according to
the standard OSPF routing protocol. While the boundary routers of multiple areas will have to
summarize the information from the routers of all areas to the backbone area that is identified
as Area 0, and then the backbone area will advertise these summary to the other areas. As
below is the model of area partition.
Figure 10-36 Area Model
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As shown above, a large-scale network is divided into three areas: Area 0, Area 1 and Area 2.
Area 1 and Area 2 exchange the routing information via Backbone Area, which has to maintain
its network connectivity at all time. The non-backbone Area 1 and Area 2 cannot communicate
directly with each other, but they can exchange routing information through the backbone Area
0. On large-scale networks, an appropriate area partition can help greatly to save network
resources and enhance the speed of the routing.
After the area partition in the network, routers of different type need to accomplish different
tasks. Different areas need to transmit the routing information to the backbone area in different
ways, due to their different locations relative to the backbone area. In the following, we will
introduce the details involved after the area partition.
1. Router Type
As Figure 10-35 shows, after the area partition of the network, the routers need to accomplish
different tasks due to their locations in different areas, according to which the routers can be
classified into 4 types: Internal Router (IR), Backbone Router (BR), Area Boundary Router (ABR)
and Autonomous System Boundary Router (ASBR).
Figure 10-37 Classification of Routers
Responsibilities of different routers divide as Table 10-2.
Router
Name
Features Responsibility
IR All the routing
interfaces belong to
the same area
Flood and exchange its all link and interface information
with the adjacent routers in the same area, thus to
synchronize the link state database with the intra-area
routers.
BR At least one routing
interface belongs to
the backbone area
Summarize the routing topology information from all areas
in AS via ABR and forward the communication data for all
areas.
ABR Connect one or more
areas to the backbone
area
Maintain independent link state databases fo
r different
areas, and deliver the topology information of each area to
the other areas via the backbone area.
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Router
Name
Features Responsibility
ASBR Connect with the
routers outside the
OSPF AS by other
routing protocol
Maintain independent routing tables for different routing
protocols, import the routing information learned by other
routing protocol to OSPF domain through a certain
standard, and then establish a uniform routing table.
Table 10-2 Router Types
2. Virtual Link
In practice, some physical restrictions might keep ABR of some areas from directly connecting
to the backbone area, which can be solved by configuring an OSPF virtual link. Virtual link
sketch is shown as below.
Figure 10-38 Virtual Link Sketch
As in Figure 10-36, ABR of Area 2 has no physical link to connect directly with the backbone
area, in which case Area 2 could not communicate with others without configuring a virtual link.
Then a virtual link between ABR1 and ABR2, passing through Area 1, could provide a logical link
for Area 2 to connect with the backbone area.
A virtual link is a point-to-point connection between two ABRs. Hence, simply configuring the
virtual link parameters on two ordinary router interfaces makes two ends of the virtual link. Two
ABR directly forward the OSPF packets to each other’s interface IP address, while the OSPF
routers between them transmit these packets as regular IP packets.
In general, configuring a virtual link is a temporary means to fix the problems of network
topology, which usually would to certain degree complicate the network. Therefore, when
networking in reality, a virtual link should be avoided if possible.
3. Route Types
OSPF prioritize routes into four levels:
1) Intra-area route
2) Inter-area route
3) Type-1 external route: It has high credibility and its cost is comparable with the cost of an
OSPF internal route. The cost from a router to the destination of the Type-1 external route
equals to the cost from the router to the corresponding ASBR plus that from the ASBR to
the destination of the external route.
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4) Type-2 external route: It has low credibility, so OSPF considers the cost from the ASBR to
the destination of the Type-2 external route is much bigger than the cost from the ASBR to
an OSPF internal router. Therefore, the cost from the internal router to the destination of
the Type-2 external route equals to that from the ASBR to the destination of the Type-2
external route. If two routes to the same destination have the same cost, then take the cost
from the router to the ASBR into consideration.
Intra-area route and inter-area route describe the internal network structure of the
autonomous system, while the external routes tell how to select the route to the destination
outside the autonomous system.
4. Stub Area and NSSA Area
An area that can connect to the autonomous system and forward the communication data to
external areas only through ABR could be set as Stub Area. Once an area is set to be Stub Area,
ABR would no longer flood the external routing information described by the AS-External LSA
to it, and meanwhile a default route with a target network 0.0.0.0 would be generated. This
default routing would be announced to the other routers in the area. All the packets forwarded
to external areas would be sent to ABR and then be forwarded outwards through it. Since there
is no need to learn about the routing information from other areas, the size of the routing table
of the routers in the stub area as well as the number of the routing message transferred would
be reduced greatly.
NSSA (Not-So-Stubby-Area) has a lot in common with stub area, but is not completely the same.
NSSA doesn’t allow ABR to import the external routing information described by AS-External
LSA, either. But it does allow ASBR in the area to spread in the NSSA the routing information as
Type-7 LSA, which is learned by other routing protocols. Upon receiving it, ABR in the area
would transform it to AS-External LSA and then flood to the whole autonomous system.
5. Route Summarization
Route summarization is to summarize routing information with the same prefix with a single
summarization route and then distribute it to other area. Via ABR route summarization a
Summary LSA will be distributed to other areas, while via ASBR route summarization an
AS-External LSA will be distributed to the entire AS. Therefore, route summarization will greatly
reduce the size of LSBD.
ABR Route Summarization: When the network reaches a certain size, to configure route
summarization on the ABR could summarize the intra-area route to be a wider one and then
distribute it to other areas, which could receive less the routing entries. As Figure 10-37 shows,
in Area 1 ABR1 can configure a summarization route 192.161.0.0/16 and advertise it to the
backbone area, while in Area 2 ABR2 can configure an summarization route 192.162.0.0/16 and
advertise it to the backbone area.
Please pay attention to that, if the network is planned to be discontinuous subnets, you need to
configure the route summarization with great caution; otherwise, it might cause some
unreachable network conditions. As Figure 10-38 shown, configuring the summarization route
192.161.0.0/16 on ABR1 and ABR2 might result in the inaccessible routing. Under such
circumstance, it is suggested to configure route summarization on only one ABR.
ASBR Route Summarization: If a route summarization is configured on an ASBR, the
AS-External LSA in the specified address range will be summarized. When NSSA is configured,
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Type-7 LSA in the specified address range will also be summarized. Following a similar principle
with ABR route summarization, ASBR summarizes routes of different type.
Figure 10-39 ABR Route Summarization
Figure 10-40 Discontinuous Network Segment
Link State Database
When the routers in the network completely synchronize the link state database through LSA
exchanges, they can calculate the shortest path tree by basing themselves as the root node.
The OSPF protocol routing calculation is simply presented as below.
1) Each OSPF router would generate LSA according to its own link state or routing
information, and then send it through the update packets to the other OSPF routers in the
network. LSA is to describe the network topology and the routing information. For instance,
Router-LSA describes the link state of routers; Summary-LSA describes the inter-area
route; and so on.
2) Each OSPF router collects LSA advertised by the other routers to form an LSDB. All the
Router-LSA and Network-LSA in the LSDB describe the entire intra-area network topology,
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while the other types of LSA describe the route to a certain destination in other areas or
external AS.
3) When all the routers in the network completely synchronize their LSDB, each OSPF router
will calculate a loop-free topology by SPF algorithm to describe the shortest path to every
destination in the network as it knows. This loop-free topology is so-called the SPF
algorithm tree.
4) Each router will establish its own routing table according to the SPF algorithm tree.
OSPF Protocol Packet Type
During the entire learning process, OSPF routing protocol uses five types of packet, all of which
are IP packets. The packets with 89 as its IP header protocol segment are OSPF ones. This
device abides by the standard RFC protocol. And we are going to introduce the packet formats
involved in the course of OSPF routing protocol running according to the definition by RFC
documentation, and attached with the images and the meaning of key segments.
1. OSPF Header
In the course of routing learning, OSPF uses five types of packet, which have the same OSPF
header, as shown below.
Figure 10-41 OSPF Header
1) Version: The version number of OSPF run by this device. For instance, the OSPF run by our
IPv4 devices is of Version 2, and that run by IPv6 devices is of Version 3.
2) Type: The type of this packet. There are totally five types of OSPF packets, as shown in the
table below.
Type Code Packet Name
1 Hello Packet
2 Database Description Packet
3 Link State Request Packet
4 Link State Update Packet
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5 Link State Acknowledgement Packet
Table 10-3 OSPF Packet Type
3) Router ID: ID of the router sending this packet.
4) Area ID
：
ID of the area that the router interface sending this packet belongs to.
5) Authentication Type: The authentication type applied by this packet. The segment
marked with * in the rear is regarded as essential information of authentication, as shown in
the table below.
Type
Code
Authentication
Name
Features
0 Non-Authentication The 64-
bit authentication information fields behind
are all 0.
1 Plain-text
Authentication
The 64-
bit authentication information behind is the
password to authenticate.
2 MD5 Ciphertext
Authentication
The Key ID, authentication data length and
encryption serial number work together to perform
MD5 Ciphertext Authentication
Table 10-4 Authentication Type
2. HELLO Packet
OSPF routers send Hello packets to each other to find neighbor routers in the network and to
maintain the mutual adjacency relationship. Only when two routers send Hello packets carrying
the same interface parameters, can they become neighbors.
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Figure 10-42 HELLO Packet
1) Netmask: Netmask of the router interface forwarding Hello packet. Only when the netmask
of the forwarding interface and that of the receiving interface coincide, can these two
routers be neighbors.
2) Hello Interval: Interval of a sequence of Hello packets sending by the forwarding interface.
Only the routers with the same Hello interval can become neighbors.
3) Router Priority: This field decides the election result for DR/BDR in the network segment.
The greatest value means the highest priority of the advertising router and also the
possibility of being elected as the DR in the segment, while the value 0 means no election
right.
4) Router Dead Interval: When the receiving router doesn’t receive another Hello packet
update from the advertising router within the specified age time, it will delete the
advertising router from its neighbor table. Only routers with the coincident dead interval
can be neighbors.
5) Designated Router ID: The interface IP of the router specified by the advertising router in
the advertising interface network.
6) Backup Designated Router ID: The interface IP of the backup router specified by the
advertising router in the advertising interface network.
7) Neighbor: All the neighbor tables of the advertising router, listing the neighbor interface IP
addresses in each interface network segment.
3. DD Packet
Two routers after becoming neighbors will send to each other the header of all routing
information in its link state database through the DD packets, in which way the receiving router
could synchronize the database.
Figure 10-43 DD Packet
1) Interface MTU: Size in bytes of the largest IP packet that can be sent out by the routing
interface of the advertising router.
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2) I: The Initial bit. During the synchronization of link state database between two routers, it
may require multiple DD packets to be forwarded, among which the first DD packet will set
its initial bit to 1, while the others 0.
3) M: The More bit. When the forwarded DD packet is not the last one database, it will set its
More Bit to 1, while the last DD packet will set the M-Bit to be 0.
4) MS: The Master/Slave bit. Before the synchronization of the link state database between
two routers, master/slave router needs to be elected, which in general is decided by such
parameters as the router priority, router ID and etc. After the election, the master router
will dominate the process of database synchronization. The DD packet forwarded by the
master router would set its MS bit to 1, while that by the slave router would set the MS bit
to 0.
5) DD Sequence Number: After the master/slave router having been elected, the master
router randomly determines the sequence number of the first DD packet, and then the
sequence number of the following DD packets increments by one. In this way, the whole
synchronization process will carry on in good order.
6) LSA header: The LSA header of the whole or partial link state database of the advertising
router, whose uniqueness identifies a LSA.
4. LSR Packet
During the synchronization of the link state database between two routers, if one router finds
an updated LSA or an LSA it doesn’t have in the DD packet forwarded, it could send a LSR
packet to request for a complete LSA.
Figure 10-44 LSR Packet
1) Link State Type: The type of LSA. There are 11 types of LSA in total: Router LSA, Network
LSA, Network Summarization LSA, ASBR Summarization LSA, and so on. In the following, all
these would be introduced in details.
2) Link State ID: It has different meanings for different types of LSA. The Link State ID of
Router LSA stands for the ID of advertising router; that of Network LSA stands for the
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interface IP address of the DR; and that of Network Summarization LSA stands for the IP
address of the network or subnet advertised; and etc.
3) Advertising Router: Router ID of the router advertising this LSA.
5. LSU Packet
When one router receives an LSR, it would send an LSU packet to inform the other the
complete LSA information. The router receiving the LSA update will re-encapsulate this LSA
and then flood it.
Figure 10-45 LSU Packet
1) LSA Quantity: The quantity of LSA included in the LSU.
2) LSA: A complete description of LSA.
6. LSAck Packet
When receiving a LSU, the router will send to the router forwarding the LSU packet a LSAck
packet including the LSA header it receives to confirm whether the data received is correct.
7. LSA
OSPF protocol defines area and multiple router types. Via various sorts of LSA, different types
of router complete routing update caused by network changes. OSPF protocol defines 11
types of LSA, which all have the same LSA header. As shown below, every LSA is unique in the
network, and could be identified uniquely by the key field of LSA header.
Figure 10-46 LSA Header
1) Age: The time passed since the LSA is generated. When the age goes over the threshold
value set by the router system, which is one hour, and the router doesn’t receive an LSA
update, it will delete this LSA.
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2) Type: The type of LSA. Table 10-5 enumerates several common features of LSA.
3) Link State ID: It has different meanings for different types of LSA. For details please refer
to the RFC documentation.
4) Advertising Router: ID of the router advertising this LSA.
5) Sequence Number: It indicates the uniqueness of a certain LSA, whose update would be
flooded to the network by adding 1 to the sequence number.
In the table below are the features of 6 types of common LSA.
Type
Code
Name Features
1 Router LSA
Originates from all the routers, and describes the router
interface which itself has already run the OSPF features and
then spreads in its advertising area.
2 Network LSA
Originates from DR, and describes the link state of all routers
in its connected network segment and then diffuses in its
advertising area.
3 Network
Summary
LSA
Originates from ABR, and describes the routers of all
segments in the area and then advertises to the backbone
area, the routers in which area will re-
summarize and then
announce to the other area.
4 ASBR
Summary
LSA
Originates from ABR, and describes the routers from ABR to
ASBR and advertises the path to ASBR to the area ABR
connects.
5
AS External
LSA
Originates from ASBR, and describes the external route and
the accessible network obtained by other routing protocols.
This type of LSA will be flooded to the entire autonomous
system.
6 NSSA
External LSA
Originates from ASBR in the NSSA. The content of this LSA is
the same as that of AS external LSA, but it would be
advertised only to NSSA. ABR can transform this type of
routing information to AS external LSA and then flood it to the
entire AS.
Table 10-5 Types of LSA
OSPF Features Supported by the Switches
This switch, supporting standard OSPF routing features, is applicable to multiple network
environments and able to meet the common networking requirements in the Ethernet scene.
The OSPF features supported are listed as follows.
1) Multi-process – The switch can establish multiple routing processes, independent of each
other and having independent database. Each routing interface belongs only to one
specific process. In short, multi-process on one switch is to divide one switch into several
independent switches logically.
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2) Area Partition – The switch can divide an autonomous system into different areas
according to the user-specified principle. The routers in the same area only need to
synchronize LSA with the other routers in its area, which can save routing resources and
lower routing performance requirements, thus to reduce networking cost.
3) Configuration of multiple equal-cost routes to balance load and backup lines.
4) Route redistribution –OSPF can import routing information learned by other routing
protocols or other OSPF processes.
5) Plaintext authentication and MD5 authentication supported when two neighbor routers in
the same area are performing message interaction, which can improve the security.
6) Customized configuration of multiple interface parameters, including the interface cost,
the retransmit interval, the transmit delay, the router priority, the router dead time, the hello
interval and authentication key, etc. in order to satisfy multiple network requirements with
flexibility.
7) Configuration of virtual link – When a network being divided into several areas, it can
connect the areas physically located far away to the backbone network through virtual link.
8) Configuration of Stub Area and NSSA.
9) ABR route summarization – to summarize the intra-area routing information with the same
prefix with a single route and then distribute it to other areas.
Configuration Introduction
OSPF protocol defines various parameters to guarantee the normal operation of the OSPF
function. The configurations of all the routers in the AS should be unitedly planned, which adds
complexity to the implement of the OSPF function to some extent. However, in a practical
scenario, most of these parameters need no configurations unless there are special
requirements. Users can keep the default values of these parameters and configure the basic
ones. The necessary steps to configure OSPF protocol is shown below:
1) Enable routing features on the switches. The routing features are enabled by default.
2) Create the routing interfaces and configure their IP parameters.
3) Plan the areas to which the subnets (routing interfaces) of the switches belong.
4) Configure the OSPF processes on each switch.
5) Configure the routing interfaces and the areas they belong to under the corresponding
OSPF processes.
The OSPF routing protocol will run normally after the above configurations. A special topology
network requires further reading of introductions to the web configuration pages below to
optimize the corresponding parameters.
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10.9.1 Process
Choose the menu Routing→OSPF→Process to load the following page.
Figure10-47 OSPF Process
Configuration Procedure:
1) Specify a Process ID.
2) Configure the router ID.
3) Click Apply.
Entry Description:
OSPF Process Config
Process ID:
The 16 bit integer that uniquely identifies the OSPF process,
ranging from 1 to 65535.
Router ID:
The 32 bit unsigned integer in dotted decimal format that
uniquely identifies the router within the autonomous system
(AS).
OSPF Process Table
Select:
Select the desired item for configuration. It is multi-optional.
Process ID:
Displays the configured OSPF process.
Active Router ID: Displays the active router ID that is currently used by the
process.
Router ID:
Displays the router ID that you configured before. When you
change the router ID of a process, it will not take effect until
you restart the process.
Status: Displays the status of the process.
Running: The process is running and its
router ID has
been configured or auto selected.
Pending: The process has no router ID and cannot start.
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10.9.2 Basic
Choose the menu Routing→OSPF→Basic to load the following page.
Figure 10-48 OSPF Base
Configuration Procedure:
1) Select a process to configure.
2) Configure the relevant parameters and functions.
3) Click Apply.
Entry Description:
Select Current Process
Current Process:
Select the desired OSPF process for configuration.
Default Route Advertise Config
Originate:
When this parameter is Enable, OSPF originates an
AS-External LSA advertising a default route (0.0.0.0/0.0.0.0).
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Always:
If Originate is Enable, but the Always option is DISABLE,
OSPF will only originate a default route if the router already
has a default route in its routing table. Set Always to ENABLE
to force OSPF to originate a default route regardless of
whether the router has a default route.
Metric:
Specify the metric of the default route. The valid value
ranges from 1 to 16777214 and the default is 1.
Metric Type:
Set the OSPF metric type of the default route. Two types are
supported: External Type 1 and External
Type 2. The default
value is External Type 2.
OSPF Config
ASBR Mode:
The router is an Autonomous System Boundary Router if it is
configured to redistribute routes from another protocol, or if
it is configured to originate an AS-
External LSA advertising
the default route.
ABR Status:
The router is an Area Border Router if it has active
non-virtual interfaces in two or more OSPF areas.
Distance:
Specify OSPF route distance. When more than two
protocols have routes to the same destination, only the
route w
hich have smallest distance will be inserted to IP
routing table. The valid value ranges from 0 to 255 and the
default is 110.
RFC 1583
Compatibility:
Select the preference rules that will be used when choosing
among multiple AS-external LSAs advertising
the same
destination. If you select Enable, the preference rules will be
those defined by RFC 1583. Else the preference rules will be
those defined in RFC 2328, which will prevent routing loops
when AS-
external LSAs for the same destination have been
origi
nated from different areas. All routers in the OSPF
domain must be configured the same. The default value is
'Enable'.
SPF Delay Time:
The number of seconds from when OSPF receives a
topology change to the start of the next SPF calculation. The
valid valu
e ranges from 1 to 600 seconds and the default is
5.
SPF Hold Time:
The minimum time in seconds between two consecutive SPF
calculations. The valid value ranges from 1 to 600 seconds
and the default is 10.
External LSA Count:
The number of AS-External LSAs in the link state database.
External LSA
Checksum:
The sum of the LS checksums of the AS-
External LSAs
contained in the link-state database.
LSAs Originated:
This value represents the number of LSAs originated by this
router.
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LSAs Received: The numbe
r of LSAs received from other routers in OSPF
domain.
Default Metric:
Set a default for the metric of redistributed routes. The valid
value ranges from 1 to 16777214.
Maximum Paths:
Set the number of paths that OSPF can report for a given
destination. Th
e valid value ranges from 1 to 16 and the
default is 16.
Reference
Bandwidth:
Specify the reference bandwidth in megabits per second.
The valid value ranges from 1 to 4294967 Mbps and the
default is 100Mbps.
Passive Default: Configure the global passive
mode settings for all OSPF
interfaces. Configuring this field will overwrite any present
interface level passive mode settings. OSPF does not form
adjacencies on passive interfaces, but does advertise
attached networks as stub networks. The default value i
s
'Disable'.
10.9.3 Network
You can configure networks contained by an area on this page. The interfaces, whose IP
address fall into the networks, will be imported to the associated area.
Choose the menu Routing→OSPF→Network to load the following page.
Figure 10-49 OSPF Network
Configuration Procedure:
1) Select a process to configure.
2) Configure the IP address, wildcard mask and area ID.
3) Click Apply.
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Entry Description:
Network Config
Process ID:
Select the desired OSPF process for configuration.
IP Address:
The IP address of the network.
Wildcard Mask:
The wildcard mask of the network. Normal subnet mask is
also supported.
Area ID: The 32 bit unsigned integ
er that uniquely identifies the area
to which a router interface connects. If you assign an Area ID
which does not exist, the area will be created with default
values. It can be in decimal format or dotted decimal format.
Network Table
Process:
Select one OSPF Process to display its network list.
Select:
Select the desired item for configuration. It is multi-optional.
IP Address:
Displays the IP address of the network.
Wildcard Mask:
Displays the wildcard mask of the network.
Area ID:
Displays the area to which the network belongs.
10.9.4 Interface
Choose the menu Routing→OSPF→Interface to load the following page.
Figure10-50 OSPF Interface
Entry Description:
Interface Table
Select:
Select the desired item for configuration. It is multi-optional.
Interface:
The interface for which data is to be displayed or configured.
IP Address/Mask:
The IP address and subnet mask of the interface.
Process:
The process to which the interface belongs.
Area ID:
The area to which a router interface connects.
Router Priority: The
router priority for the selected interface. The priority of
an interface is specified as an integer from 0 to 255. A value
of '0' indicates that the router is not eligible to become the
designated router on this network. The default is 1.
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Retransmit Interval:
The retransmit interval for the specified interface. This is the
number of seconds between link-
state advertisements for
adjacencies belonging to this router interface. This value is
also used when retransmitting database descriptions and
link-state r
equest packets. The valid value ranges from 1 to
65535 seconds and the default is 5 seconds.
Hello Interval:
The hello interval for the specified interface in seconds. This
parameter must be the same for all routers attached to a
network. The valid value
ranges from 1 to 65535 seconds
and the default is 10 seconds.
Dead Interval:
The dead interval for the specified interface in seconds. This
specifies how long a router will wait to see a neighbor
router's Hello packets before declaring that the router is
down. This parameter must be the same for all routers
attached to a network. The valid value ranges from 1 to
65535 seconds and the default is 40.
Transmit Delay:
The Transit Delay for the specified interface. This specifies
the estimated number of second
s it takes to transmit a link
state update packet over the selected interface. The valid
value ranges from 1 to 65535 seconds and the default is 1
second.
Cost:
The link cost. OSPF uses this value in computing shortest
paths. The valid value ranges from 1 to 65535.
Network Type:
The OSPF network type on the interface. The default
network type for Ethernet interfaces is broadcast.
Passive Mode:
Make an interface passive to prevent OSPF from forming an
adjacency on an interface. OSPF advertises networks
at
tached to passive interfaces as stub networks. Interfaces
are not passive by default.
MTU Ignore:
Disables OSPF MTU mismatch detection on received
database description packets. Default value is Disable (MTU
mismatch detection is enabled).
Database Filter: To prevent outgoing link-
state advertisements (LSAs)
flooding out of an OSPF interface. The default is Disable, all
outgoing LSAs are flooded out of the interface.
Authentication
Type:
Displays the authentication type of the interface. One of the
following:
null: No authentication.
simple: Use simple password.
md5: Use md5 message-digest algorithm.
Simple Key:
Displays the active simple password of the interface.
MD5 Key ID:
Displays the active MD5 key ID of the interface.
MD5 Key:
Displays the active MD5 key of the interface.
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State:
Displays the current state of the selected router interface.
One of the following:
Down:
This is the initial interface state. In this state, the
lower-
level protocols have indicated that the interface
is unusable. In this
state, interface parameters will be
set to their initial values. All interface timers will be
disabled, and there will be no adjacencies associated
with the interface.
Loopback:
In this state, the router's interface to the
network is looped back either in
hardware or software.
The interface is unavailable for regular data traffic.
However, it may still be desirable to gain information on
the quality of this interface, either through sending
ICMP pings to the interface or through something like a
bit error
test. For this reason, IP packets may still be
addressed to an interface in Loopback state. To
facilitate this, such interfaces are advertised in router-
LSAs as single host routes, whose destination is the
interface IP address.
Waiting: The router is tryi
ng to determine the identity of
the (Backup) Designated Router by monitoring received
Hello Packets. The router is not allowed to elect a
Backup Designated Router or a Designated Router until
it transitions out of Waiting state. This prevents
unnecessary changes of (Backup) Designated Router.
DR:
This router is itself the Designated Router on the
attached network. Adjacencies are established to all
other routers attached to the network. The router must
also originate a Network LSA for the network node. The
Network LSA will contain links to all routers (including
the Designated Router itself) attached to the network.
BDR:
This router is itself the Backup Designated Router
on the attached network. It will be promoted to
Designated Router if the present Designa
ted Router
fails. The router establishes adjacencies to all other
routers attached to the network. The Backup
Designated Router performs slightly different functions
during the Flooding Procedure, as compared to the
Designated Router.
DR Other: The interfa
ce is connected to a broadcast on
which other routers have been selected to be the
Designated Router and Backup Designated Router
either. The router attempts to form adjacencies to both
the Designated Router and the Backup Designated
Router.
Designated Router:
The identity of the Designated Router for this network, in the
view of the advertising router. The Designated Router is
identified here by its router ID. The value 0.0.0.0 means that
there is no Designated Router.
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Backup Designated
Router:
The ident
ity of the Backup Designated Router for this
network, in the view of the advertising router. The Backup
Designated Router is identified here by its router ID. Set to
0.0.0.0 if there is no Backup Designated Router.
Number of Events: This is the number of
times the specified OSPF interface has
changed its state.
Click Edit to display the following figure:
Figure 10-51 Interface Config
Configuration Procedure:
1) Configure the OSPF parameters of the interface.
2) Click Apply.
Entry Description:
Interface Config
Interface:
Displays the interface ID for configuration.
Router Priority:
The router priority for the selected interface. The priority of
an interface is specified as an integer from 0 to 255. A value
of '0
' indicates that the router is not eligible to become the
designated router on this network. The default is 1.
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Retransmit Interval:
The retransmit interval for the specified interface. This is the
number of seconds between link-
state advertisements for
ad
jacencies belonging to this router interface. This value is
also used when retransmitting database descriptions and
link-
state request packets. The valid value ranges from 1 to
65535 seconds and the default is 5 seconds.
Hello Interval: The hello interval
for the specified interface in seconds. This
parameter must be the same for all routers attached to a
network. The valid value ranges from 1 to 65535 seconds
and the default is 10 seconds.
Dead Interval: The dead interval for the specified interface in seconds. This
specifies how long a router will wait to see a neighbor
router's Hello packets before declaring that the router is
down. This parameter must be the same for all routers
attached to a network. The valid value ranges from 1 to
65535 seconds and the default is 40 seconds.
Transmit Delay:
The Transit Delay for the specified interface. This specifies
the estimated number of seconds it takes to transmit a link
state update packet over the selected interface. The valid
value ranges from 1 to 65535 se
conds and the default is 1
second.
Cost:
The link cost. OSPF uses this value in computing shortest
paths. The valid value ranges from 1 to 65535.
Network Type:
Sets the OSPF network type. The default network type for
Ethernet interfaces is broadcast.
Passive Mode:
Make an interface passive to prevent OSPF from forming an
adjacency on an interface. OSPF advertises networks
attached to passive interfaces as stub networks. Interfaces
are not passive by default.
MTU Ignore: Disables OSPF MTU mismatch detect
ion on received
database description packets. Default value is Disable (MTU
mismatch detection is enabled).
Database Filter: To prevent outgoing link-
state advertisements (LSAs)
flooding out of an OSPF interface. The default is Disable, all
outgoing LSAs are flooded out of the interface.
Authentication
Type:
The authentication type of interface. The choices are:
null: No authentication.
simple: Use simple password.
md5: Use md5 message-digest algorithm.
Simple Key:
Displays the active simple password of the interface.
MD5 Key ID:
Displays the active MD5 key ID of the interface.
MD5 Key:
Displays the active MD5 key of the interface.
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10.9.5 Area
Choose the menu Routing→OSPF→Area to load the following page.
Figure10-52 OSPF Area
Configuration Procedure:
1) Select a process, and configure the OSPF parameters of the area.
2) Also you can selelct an entry in the Area Table, and change the configuration of the area.
3) Click Apply.
Entry Description:
Area Config
Process ID:
Select the desired OSPF process for configuration.
Area ID:
The 32 bit unsigned integer that uniquely identifies the area.
It can be in decimal format or dotted decimal format.
Area Type:
OSPF area type: Normal, Stub, or NSSA.
Default Cost:
The metric value you want to apply for the default
Summary-
LSA advertised into the stub area. The valid value
ranges from 1 to 16777214.
Summary: Set whether or not th
e specified Area will allow Summary
Link-
State Advertisements (Summary LSAs) to be imported
into the area from other areas. It is always Enable in Normal
areas. The default is Enable.
Redistribution: Set whether or not the external routes will be redistri
buted
to the area. It is always Enable in Normal areas and always
Disable in Stub areas.
Default Route
Advertise:
Enable or disable advertising default route (0.0.0.0/0.0.0.0)
into NSSA area by sending a NSSA-
External LSA. It is only
available in NSSA area.
Metric Type:
Set the OSPF metric type of the default route. Two types are
supported: External Type 1 and External Type 2. The default
value is External Type 2.
Metric:
Specify the metric of the default route. The valid value
ranges from 1 to 16777214 and the default is 1.
229
Area Table
Process:
Select one OSPF Process to display its area list.
Select:
Select the desired item for configuration. It is multi-optional.
Area ID:
Displays the configured area.
Area Type:
Displays the type of the area and it can be modified.
Summary:
Displays the Summary parameter and it can be modified.
Redistribution:
Displays the Redistribution parameter and it can be
modified.
Default Cost:
Displays the stub cost of the area and it can be modified.
Default Route
Advertise:
Displays the Default Route Advertise status and it can be
modified.
Metric Type: Displays the type of default route and it can be modified.
Metric:
Displays the metric of default route and it can be modified.
SPF runs: Displays the number of times that the intra-
area route table
has been calculated using this area's link-
state database.
This is typically done using Dijkstra's algorithm.
ABR Count:
Displays the total number of area border routers reachable
within this area. This is initially zero, a
nd is calculated in each
SPF Pass.
Area LSA Count: Displays the total number of link-
state advertisements in this
area's link-state database, excluding AS-External LSAs.
Area LSA
Checksum:
Displays the 32-bit unsigned sum of the link-
state
advertisements
' LS checksums contained in this area's
link-
state database. This sum excludes external (LS type 5)
link-
state advertisements. The sum can be used to
determine if there has been a change in a router's link state
database, and to compare the link-state data
bases of two
routers.
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10.9.6 Area Aggregation
You can configure address ranges for an area on this page. The address range is used to
consolidate or summarize routes for an area at an area boundary. The result is that a single
summary route is advertised to other areas by the ABR. Routing information is condensed at
area boundaries, a single route is advertised for each address range.
Choose the menu Routing→OSPF→Area Aggregation to load the following page.
Figure10-53 OSPF Area Aggregation
Configuration Procedure:
1) Select a process.
2) Configure the relevant parameters.
3) Click Apply.
Entry Description:
Area Aggregation Config
Process ID:
Select the desired OSPF process for configuration.
Area ID: The 32 bit unsigned
integer that uniquely identifies the area.
It can be in decimal format or dotted decimal format.
IP Address:
The IP address of the address range.
Subnet Mask:
The subnet mask of the address range.
Cost: Specify the path cost to the address range. If not
specified,
it will be dynamic calculated by OSPF. The valid value ranges
from 1 to 16777214.
Advertise:
Set whether or not the area address range will be advertised
outside the area via a Network-
Summary LSA. The default is
Enable.
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Area Aggregation Table
Process:
Select one OSPF Process to display its address range list.
Area ID:
Displays the area to which the address range belongs.
Select:
Select the desired item for configuration. It is multi-optional.
IP Address:
Displays the IP address of the address range.
Subnet Mask:
Displays the subnet mask of the address range.
Cost:
Displays the path cost to the address range and it can be
modified.
Advertise:
Displays the Advertise parameter and it can be modified.
10.9.7 Virtual Link
Choose the menu Routing→OSPF→Virtual Link to load the following page.
Figure10-54 Virtual Link
Configuration Procedure:
1) Select a process.
2) Configure the relevant parameters.
3) Click Apply.
Entry Description:
Virtual Link Creation
Process ID:
Select the desired OSPF process for configuration.
Transit Area ID:
The ID of the transit area. Virtual links can be configured
between any pair of area border routers having interfaces to
a common (non-
backbone) area. Here the common area is
named Transit Area.
Neighbor Router ID: The router ID of the neighbor portion of a virtual link.
Virtual Link Table
Select:
Select the desired item for configuration. It is multi-optional.
Interface: Displays the virtual interface. When you create a virtual
link,
actually a virtual interface is created.
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Transit Area ID: Displays the transit area ID of the virtual link.
Neighbor Router ID: Displays the neighbor router ID of the virtual link.
Retransmit Interval: The retransmit interval for the specified in
terface. This is the
number of seconds between link-
state advertisements for
adjacencies belonging to this router interface. This value is
also used when retransmitting database descriptions and
link-
state request packets. The valid value ranges from 1 to
65535 seconds and the default is 5 seconds.
Hello Interval:
The hello interval for the specified interface in seconds. This
parameter must be the same for all routers attached to a
network. The valid value ranges from 1 to 65535 seconds
and the default is 10 seconds.
Dead Interval:
The dead interval for the specified interface in seconds. This
specifies how long a router will wait to see a neighbor
router's Hello packets before declaring that the router is
down. This parameter must be the same for all rou
ters
attached to a network. The valid value ranges from 1 to
65535 seconds and the default is 40.
Transmit Delay:
The Transit Delay for the specified interface. This specifies
the estimated number of seconds it takes to transmit a link
state update packet
over the selected interface. The valid
value ranges from 1 to 65535 seconds and the default is 1
second.
Authentication
Type:
You may select an authentication type other than none by
clicking on the 'Authentication Type' button. The choices
are:
null: No authentication.
simple: Use simple password.
md5: Use md5 message-digest algorithm.
Simple Key: Displays the active simple password of the interface.
MD5 Key ID: Displays the active MD5 key ID of the interface.
MD5 Key: Displays the active MD5 key of the interface.
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State:
Displays the current state of the selected router interface.
One of:
Down:
This is the initial interface state. In this state, the
lower-
level protocols have indicated that the interface
is unusable. In this state, interface parameter
s will be
set to their initial values. All interface timers will be
disabled, and there will be no adjacencies associated
with the interface.
P2P:
In this state, the interface is operational, and
connects either to a physical point-to-
point network or
to a
virtual link. Upon entering this state, the router
attempts to form an adjacency with the neighboring
router. Hello Packets are sent to the neighbor every
HelloInterval seconds.
10.9.8 Route Redistribution
Choose the menu Routing→OSPF→Route Redistribution to load the following page.
Figure10-55 Route Redistribution
Configuration Procedure:
1) Select a Source to be enabled with Route Redistribution.
2) Enable Route Redistribution and configure the relevant parameters.
3) Click Apply.
Entry Description:
Route Redistribution
Process:
Select one OSPF Process to display its route redistribution
list.
Select:
Select the desired item for configuration. It is multi-optional.
Source: The av
ailable source routes for redistribution by OSPF. The
valid values are 'Static', 'RIP', ‘Connected’, and other OSPF
processes.
Redistribute:
This option enables or disables the redistribution for the
selected source protocol.
Metric: Set the metric value
to be used as the metric of redistributed
routes. The valid value ranges from 1 to 16777214 and the
default is equal to Default Metric configured on Basic page.
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Metric Type:
Set the OSPF metric type of redistributed routes. The
default is External Type 2.
Tag:
Set the tag field in routes redistributed. The valid value
ranges from 0 to 4294967295 and the default is 0.
10.9.9 Neighbor Table
Choose the menu Routing→OSPF→Neighbor Table to load the following page.
Figure10-56 Neighbor Table
Entry Description:
Neighbor Table
Process:
Select one OSPF Process to display its neighbor list.
Interface: Displays the
interface for which neighbor list is to be
displayed.
Neighbor IP
Address:
The IP address of the neighboring router's interface to the
attached network.
Router ID:
A 32 bit integer in dotted decimal format representing the
neighbor.
Area ID: The area ID of the OSPF area associated with the interface.
Options:
An integer value that indicates the optional OSPF
capabilities supported by the neighbor. The neighbor's
optional OSPF capabilities are also listed in its Hello packets.
Router Priority: The router priority of the neighbor.
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State: The state of the neighbor:
Down: This is the initial state of a neighbor conversation.
It indicates that there has been no recent information
received from the neighbor. On NBMA networks, Hello
packets may still be sent to 'Down' neighbors, although
at a reduced frequency.
Attempt: This state is only valid for neighbors attached
to NBMA networks. It indicates that no recent
information has been received from the neighbor, but
that a more concerted effort should be made to
contact
the neighbor. This is done by sending the neighbor Hello
packets at intervals of Hello Interval.
Init: In this state, a Hello packet has recently been seen
from the neighbor. However, bidirectional
communication has not yet been established with t
he
neighbor (i.e., the router itself did not appear in the
neighbor's Hello packet). All neighbors in this state (or
greater) are listed in the Hello packets sent from the
associated interface.
2-
Way: In this state, communication between the two
routers is
bidirectional. This has been assured by the
operation of the Hello Protocol. This is the most
advanced state short of beginning adjacency
establishment. The (Backup) Designated Router is
selected from the set of neighbors in state 2-
Way or
greater.
ExStar
t: This is the first step in creating an adjacency
between the two neighboring routers. The goal of this
step is to decide which router is the master, and to
decide upon the initial DD sequence number. Neighbor
conversations in this state or greater are ca
lled
adjacencies.
Exchange: In this state the router is describing its entire
link state database by sending Database Description
packets to the neighbor. In this state, Link State
Request Packets may also be sent asking for the
neighbor's more recent LSAs
. All adjacencies in
Exchange state or greater are used by the flooding
procedure. These adjacencies are fully capable of
transmitting and receiving all types of OSPF routing
protocol packets.
Loading: In this state, Link State Request packets are
sent to
the neighbor asking for the more recent LSAs
that have been discovered (but not yet received) in the
Exchange state.
Full: In this state, the neighboring routers are fully
adjacent. These adjacencies will now appear in Router
LSAs and Network LSAs.
Events:
The number of times this neighbor relationship has changed
state, or an error has occurred.
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Retransmission
Queue length:
An integer representing the current length of the
retransmission queue of the specified neighbor router ID of
the specified interface.
Dead Time:
The amount of time, in seconds, to wait before the router
assumes the neighbor is unreachable.
10.9.10 Link State Database
Choose the menu Routing→OSPF→Link State Database to load the following page.
Figure10-57 Link State Database
Entry Description:
Link State Database
Process:
Select one OSPF Process to display its link state database.
Area ID:
Displays the ID of the area to which the LSA belongs.
Advertising Router: Displays the ID of the router that advertising the LSA.
LSA Type:
The format and function of the link state advertisement. One
of the following: Router, Network, Network-
Summary,
ASBR-Summary, External (Type 5), NSSA-External (Type 7).
Link State ID: The Link State ID identifies the piece of the routing domain
that is being described by the advertisement. The value of
the LS ID depends on the advertisement's LS type.
Age:
The time since the link state advertisement was first
originated, in seconds.
Sequence: The sequence number field is an unsigned 32-
bit integer. It
is used to detect old and duplicate link state advertisements.
The larger the sequence number, the more recent the
advertisement.
Checksum:
The checksum is used to detect data corruption of an
advertisement. This corr
uption can occur while an
advertisement is being flooded, or while it is being held in a
router's memory. This field is the checksum of the complete
contents of the advertisement, except the LS age field.
Options: The Options field in the link state adver
tisement header
indicates which optional capabilities are associated with the
advertisement.
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10.9.11 Application Example for OSPF
Network Requirements
1. The AS is divided into three areas and all switches in the AS run OSPF.
2. Switch A and Switch B act as ABRs to forward routing information between areas.
3. Each switch can learn routing information to all the network segments in the AS after the
configuration.
Network Diagram
Configuration Procedure
Configure Switch A
Step
Operation
Description
1 Create routing
interfaces and
their IP
addresses
Required. On page Routing→Interface→Interface Config
, create
routed port 1/0/1 with the IP 1.10.1.1/24 and routed port 1/0/2 with
the IP 1.20.1.1/24.
2 Create OSPF
process
Required. On page Routing→OSPF→Process, Create OPSF process
1 and configure the Router ID as 1.1.1.1.
3 Create
networks in the
area
Required. On page Routing→OSPF→Network
, configure network
1.10.1.0/24 in area 0 and configure network 1.20.1.0/24 in area 1.
4 Configure area
aggregation
Optional. On page Routing→OSPF→Area Aggragation
, configure
the aggregation address as 1.20.0.0/16 in area 1.
Configure Switch B
Step
Operation
Description
1 Create routing
interfaces and
their IP
addresses
Required. On page Routing→Interface→Interface Config
, create
routed port 1/0/1 with the IP 1.10.1.2/24 and routed port 1/0/2 with
the IP 1.30.1.1/24.
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2 Create OSPF
process
Required. On page Routing→OSPF→Process, Create OPSF process
1 and configure the Router ID as 2.2.2.2.
3 Create
networks in the
area
Required. On page Routing→OSPF→Network
, configure network
1.10.1.0/24 in area 0 and configure network 1.30.1.0/24 in area 2.
4 Configure area
aggregation
Optional. On page Routing→OSPF→Area Aggragation
, configure
the aggregation address as 1.30.0.0/16 in area 2.
Configure Switch C
Step
Operation
Description
1 Create routing
interfaces and
their IP
addresses
Required. On page Routing→Interface→Interface Config
, create
routed port 1/0/1 with the IP 1.20.2.1/24 and routed port 1/0/2 with
the IP 1.20.1.2/24.
2 Create OSPF
process
Required. On page Routing→OSPF→Process, Create OPSF process
1 and configure the Router ID as 3.3.3.3.
3 Create
networks in the
area
Required. On page Routing→OSPF→Network
, configure network
1.20.0.0/16 in area 1.
Configure Switch D
Step
Operation
Description
1 Create routing
interfaces and
their IP
addresses
Required. On page Routing→Interface→Interface Config
, create
routed port 1/0/1 with the IP 1.30.2.1/24 and routed port 1/0/2 with
the IP 1.30.1.2/24.
2 Create OSPF
process
Required. On page Routing→OSPF→Process, Create OPSF process
2 and configure the Router ID as 4.4.4.4.
3 Create
networks in the
area
Required. On page Routing→OSPF→Network
, configure network
1.30.0.0/16 in area 2.
10.10 VRRP
VRRP (Virtual Router Redundancy Protocol) is a fault-tolerant protocol. Generally, all hosts in a
LAN (Local Area Network) would set a default route. Packets which are sent by the host and
whose destination address does not belong to the local network segment will be sent to the
gateway via the default route. Therefore, communication between the host and external
network can be established. Once the gateway fails, all hosts of this network segment whose
default next hop is the gateway will stop communicating with external network.
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VRRP is developed to solve the problem mentioned above and designed for LAN with multicast
or broadcast function, such as Ethernet. Virtual router acts as a backup group which consists
of one master router and several backup routers.
The virtual router (also a backup group) has its own IP address. This IP address can be the same
as the interface address of any router in the backup group. In this case, the virtual router is also
called IP address owner. All physical routers in the backup group have their own IP addresses.
Hosts in LAN only recognize the IP address of the virtual router, but not that of the master
router or backup routers. The IP address of the virtual router is assigned as the default gateway
for the participating routers. Hosts in LAN communicate with external network via the virtual
router. Once the master router in backup group fails, another router will be selected to replace
it from the backup group through election protocol and thus provides routing service for hosts.
Therefore, communication between hosts and external network can be established without
interruption.
Advantages of VRRP
VRRP owns the following advantages:
1. Simplified network management. In LAN with multicast or broadcast function, such as
Ethernet, even though a device fails, with the help of VRRP, highly-reliable default link can
still be provided and network interruption can be avoided after a single link fails without
reconfiguration of dynamic routing or router discovery protocols, or default gateway
configuration on every end-host.
2. Small network overhead. The single message that VRRP defines is the VRRP
advertisement, which can only be sent by the master router.
Typical Networking Application Diagram
Figure 10-58 Typical Networking Application Diagram
VRRP Operating Principle
1. Working Process
VRRP backup group, or virtual router, consists of a group of physical routers with the same
VRID (virtual route identifier). A virtual router owns one or more virtual IP addresses and one
virtual MAC address, in the format 00-00-5E-00-01-{VRID}. The IP address of the virtual
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router is assigned as the default gateway for the hosts within the LAN. Communication with
external network can be realized via the virtual router.
Master router is selected from the physical routers in the virtual router group according to
VRRP priority. The elected master router provides routing service to the hosts in LAN, and
sends VRRP messages periodically to publicize its configuration information like priority
and operating condition to other routers in backup group. Other physical routers in the
backup group work as backup routers. They monitor the VRRP packets sent by the master
router. A new master router will be elected among them to take the role of the master
router if master router fails.
2. Master Election
Initially-created routers work in Backup state and learn other members' priorities in the
virtual router via VRRP packets. The one with the highest priority is elected as master router.
If the priority values are the same, the router with the highest interface IP address is
selected as the master.
• In preemptible mode, when backup router receives VRRP packet, it will compare its
priority with that of the advertisement packet. If of higher priority, the backup router will
become the master router; otherwise, it will maintain Backup state.
• In non-preemptible mode, physical routers in the backup group will maintain Master or
Backup state as long as the master router functions normally. Even if backup router is
given higher priority, it cannot become a master router in non-preempt mode.
The VRRP priority ranges from 0 to 255 (the bigger the number is, the higher the priority is).
Configurable range is 1-254. The priority value 0 is reserved for the current master when it
gives up its role as master router. For example, when master router receives shutdown
message, it would send VRRP packet with priority 0 to the backup group which the interface
belongs to. The priority of the IP address owner must be 255. Therefore, if there exists an IP
address owner in the backup group and it works normally, it must be the master router.
3. State Transition
VRRP defines three state modes: Initialize, Master and Backup. Only in Master state can
master router provide service for forwarding request via virtual IP address and forward
VRRP packet.
When the system just starts, it comes to Initialize state. If the virtual router is not given a
virtual IP address, the system would maintain Initialize state. If the virtual IP address is
configured properly, when the system receives startup message from interface, it would
transition to the Backup state (in which case its priority is not 255) or Master state (in which
case its priority is 255). Routers in master or backup state can change to Initialize state only
when they receive shutdown message from interface. In Initialize state, router cannot deal
with VRRP packet.
If the master router functions properly, it will periodically send VRRP packets informing
backup routers in the backup group that it functions properly. VRRP timer can be manually
configured to customize the intervals that master router sends VRRP packet. If the backup
router waits for a period longer than three times the advertisement timer and fails to
receive VRRP packets from the master router, they will assume that the master router is
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dead and initiate an election process by transitioning to the Master state and forwarding
VRRP packets.
To avoid frequent Master-Backup state transition among routers in the backup group and
provide enough time for backup routers to collect necessary information, backup router
would not preempt to be master as soon as it receives packets with lower priority value. It
would wait for a certain time, which is called preempt-mode delay time, and then send
packets to take place of the former master. Users can customize the preempt-mode delay
time.
4. Authentication Methods
VRRP provides three authentication methods:
• No authentication: the eligibility of VRRP packets is not verified and no security
insurance is provided. In a safe network, no authentication can be set as authentication
method.
• Simple text password: in a network where security is possible to be threatened, simple
text password is recommended. The router which forwards the VRRP packets fills the
authentication data in the VRRP packets. The router which has received the VRRP
packets compares the data with that in local configuration. If they are the same, the
VRRP packet received is considered legitimate. If not, it would be considered as
illegitimacy.
• MD5 authentication: in a highly-unsecured network, MD5 authentication is
recommended. The router which sends the VRRP packets conducts digest operation
on VRRP packets using authentication data and MD5 algorithm. The result is saved in
Authentication Header. The router which has received the VRRP packet conducts the
same digest operation and compares the result with the content in Authentication
Header. If they match, the VRRP packet received is considered legitimate. If not, it
would be considered as illegitimacy.
Interface Tracking
This function enhances the backup function. If interface tracking is enabled, when the
master router's other interfaces which are not in this backup group (for example, the uplink
interface) fail, it would lower its priority value automatically. Therefore, router with more
available interfaces and better performance can be elected as master router; and the
stability of backup group is increased.
When the router interface connecting the uplink fails, the backup group cannot recognize
uplink breakdown. If this router is in Master state, hosts in the LAN cannot visit external
network. This problem can be solved with the help of interface tracking function. When the
interface connecting the uplink is down, the router will automatically lower its priority,
making priority of other routers in the backup group higher than its priority value. As a result,
the backup router with the highest priority becomes master.
Load Balancing
One router can work in more than one backup group, which makes it possible that a router
can be master router in one backup group and backup router in other backup groups.
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Load balancing means multiple routers undertake workloads simultaneously. Therefore,
two or more backup groups are needed to realize load balancing. Each backup group
consists of one master router and several backup routers. Master router can vary from one
backup group to the others.
Figure 10-59 VRRP Load Balancing
A router owns different priority in different backup groups when it participates in multiple
VRRP backup groups simultaneously.
In Figure 10-58, there exist three backup groups:
• Backup Group 1, corresponding to Virtual Router 1. Device A is the master router;
Device B and C are backup routers.
• Backup Group 2, corresponding to Virtual Router 2. Device B is the master router;
Device A and C are backup routers.
• Backup Group 3, corresponding to Virtual Router 3. Device C is the master router;
Device A and B are backup routers.
To realize the workload balancing among Device A, B and C, the default gateway of the
hosts associated with the LAN should be set as Virtual Router 1, 2 and 3 respectively. When
it comes to priority configuration, it would be better that the VRRP priority values of the
three virtual routers are different in order to prevent one router from being more than one
master simultaneously.
VRRP Configuration
Before configuring VRRP, users should plan well to specify the role and function of the devices
in backup groups. Every switch in backup group should be configured, which is the
precondition to construct a backup group.
10.10.1 Basic Config
VRRP (Virtual Routing Redundancy Protocol) is a function on the switch that dynamically
assigns responsibility for a virtual router to one of the VRRP routers on a LAN. The VRRP router
that controls the IP address associated with a virtual router is called the Master, and will
243
forward packets sent to this IP address. This will allow any Virtual Router IP address on the LAN
to be used as the default first hop router by end hosts.
Choose the menu Routing → VRRP → Basic Config to load the following page.
Figure10-60 VRRP Basic Config
Configuration Procedure:
1) Enter the VRID to identify the VRRP group.
2) Select an interface and assign a virtual IP address for the VRRP group.
3) Click Create.
Entry Description:
VRRP Basic Config
VRID: Enter the VRID only if you are creating a new VRRP group
.
The VRID ranges from 1 to 255.
Interface: Select the VLAN interface ID or router interface ID for
the
new VRRP group.
Virtual IP: Assign a virtual IP address for the new VRRP group. It must
be on the same network segment as the IP address of the
interface where the VRRP group is configured.
Create: Click the button to add a new VRRP group.
Clear: Click the button to clear the configuration.
VRRP Table
Select:
Select one or more items.
VRID:
Displays the VRID associated with the VRRP group.
Interface: Displays the Interface ID associated with the VRRP group.
Interface IP: Displays the IP Address
associated with the selected
interface.
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Virtual IP:
Displays the primary Virtual IP associated with the VRRP
group.
Priority: Displays the priority associated with the VRRP group.
Status: Displays the status associated with the VRRP group.
Other: Displays more information about the VRRP group.
All: Select all the VRRP items.
Delete: Delete the selected items.
Refresh
：
Update the status of the VRRP items.
Click Detail to view the detailed information of the specified VRRP group. If you do not
configure the tracked interface, the track information will not display here.
Figure 10-61 Detailed Specified VRRP Information
Entry Description:
VRID:
Displays the VRID associated with the VRRP group.
Interface: Displays the Interface ID associated with the VRRP group.
Description
：
Displays the description associated with the VRRP group.
Interface IP:
Displays the IP Address associated with the selected
interface.
Status: Displays the status associated with the VRRP group.
Configure Priority: Displays the configured priority associated with the
VRRP
group. It ranges from 1 to 255.
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Running Priority: Displays the running priority associated with the
VRRP
group. It ranges from 1 to 255.
Advertise Timer: Displays the advertise timer associated with the
VRRP
group. It ranges from 1 to 255.
Preempt Delay
Timer:
Displays the preempt delay timer associated with the
VRRP
group. It ranges from 0 to 255.
Preempt Mode: Displays the preempt mode associated with the
VRRP
group.
Authentication
Type:
Displays the authentication type associated with the
VRRP
group.
Key:
Displays the key associated with authentication type. If the
authentication type is 'normal', it will display '--'.
Primary Virtual IP: Displays the primary virtual IP associated with the
VRRP
group.
Virtual MAC: Displays the Virtual MAC address associated with the
VRRP
group.
Tracked Interface:
Displays the tracked interface ID.
Reduced Priority: Displays the reduced
priority when the tracked interface is
'down'.
Back: Click the button to go back to the VRRP Basic Config page.
Refresh: Click the button to refresh this page.
10.10.2 Advanced Config
You can modify most of features of the VRRP on this page, including the description, priority,
preempt mode, advertisement. But you cannot add or delete a VRRP group.
Choose the menu Routing → VRRP → Advanced Config to load the following page.
Figure10-62 VRRP Advanced Config
Configuration Procedure:
Select your desired VRRP group and configure corresponding parameters according to your
needs. Then click Apply.
Entry Description:
Select:
Select one or more items.
246
VRID:
Displays the VRID associated with the VRRP group.
Interface: Displays the Interface ID associated with the VRRP group.
Description: Give a description for the VRRP group. It can contain up to 8
characters. Only numbers, letters, and underlines are
allowed.
Priority: Set the priority for the device associated with the VRRP
group. It ranges from 1 to 254. The one with greater value
owns the higher priority.
Advertise Timer: Specify the interval at which the VRRP packets are sent. It
ranges from 1 to 255 seconds.
Preempt Mode: With this option enabled, a backup router will preempt the
master status if it has a priority greater than the current
master router's priority. By default, it is enabled.
Delay Time: Specify the time that a backup router has to wait for before
setting itself as the master when the current master is
considered to be unavailable. It ranges from 0 to 255
seconds.
Authentication: Select the authentication type for the Virtual Router. By
default, it is None.
None: No authentication will be performed.
Simple: Authentication will be performed using a text
password.
MD5: Authentication of MD5 will be performed using a
text password. This authentication mode has
a higher
security than Simple mode.
Key:
If you select Simple or MD5 as authentication mode, enter
the key.
10.10.3 Virtual IP Config
You can configure virtual IP for the virtual routers on this page. The virtual IP must be in the
subnet of an interface corresponding with the virtual router, can be added, deleted or modified
for the special virtual router.
247
Choose the menu Routing → VRRP → Virtual IP Config to load the following page.
Figure10-63 Virtual IP Config
Configuration Procedure:
Select the interface and VRID associated with your desired VRRP group and add one or more
virtual IP addresses for the VRRP group. Then Click Create.
Entry Description:
Add Virtual IP
Interface: Select the interface associated with your desired VRRP
group.
VRID: Select the VRID associated with your desired VRRP group.
Type:
Set the type of the virtual IP address.
Virtual IP:
Add an IP address for the VRRP group. You can add up to 32
virtual IP addresses associated with the VRRP group.
VRRP Virtual IP Table
Select:
Select one or more items.
VRID:
Displays the VRID associated with the VRRP group.
Interface: Displays the Interface ID associated with the VRRP group.
Virtual IP: Displays the virtual IP address associated with the VRRP
group.
Type: Displays the type of the virtual IP address.
Note:
Up to 32 virtual IPs can be configured for each VRRP group.
248
10.10.4 Track Config
You can configure track information for virtual routers. When the uplink interface of the master
router is down, service will be interrupted since VRRP cannot detect the status change of
interfaces outside the VRRP group. You can configure interface tracking to track the uplink
interface. In this way, the priority of the master router can be reduced when the tracked
interface is down, and the backup router will take over traffic. This ensures continuity for
network communication.
Choose the menu Routing → VRRP → Track Config to load the following page.
Figure10-64 Track Config
Configuration Procedure:
Select the interface and VRID associated with your desired VRRP group and add track
information for the VRRP group. Then Click Create.
Entry Description:
Add Track
Interface: Select the interface associated with your desired VRRP
group.
VRID: Select the VRID associated with your desired VRRP group.
Tracked Interface: Specify the interface to be tracked.
Reduced Priority: Specify the priority to reduce if the tracked interface is
down. After reducing this value, the priority of the master
router should be smaller than the priority of the backup
router.
Track Table
Select:
Select one or more items.
VRID:
Displays the VRID associated with your desired VRRP group.
249
Interface: Displays the Interface ID
associated with your desired VRRP
group.
Tracked Interface:
Displays the Interface ID tracked by the VRRP group.
Reduced Priority: Displays the reduced priority associated with the i
nterface
tracked by the VRRP group.
Link State: Displays the status of the interface tracked by the VRRP
group.
Apply: Change the selected reduced priority. A new r
educed
priority should be provided if the Apply button is clicked.
Delete:
Delete the selected interface.
Refresh
：
Update the link state of the tracked interface.
Note:
1. IP owner cannot track any interface.
2. Up to 20 interfaces can be tracked for each VRRP group.
3. When tracking the uplink interface, the devices in the VRRP group must work in
preemption mode.
10.10.5 Virtual Router Statistics
You can view global and detailed statistics of VRRP groups.
Choose the menu Routing → VRRP → Virtual Router Statistics to load the following page.
Figure10-65 Virtual Router Statistics
Global Statistics
Router Checksum
Errors:
Displays the total number of VRRP packets received with an
invalid VRRP checksum value.
Router Version
Errors:
Displays the total number of VRRP packets received with
an
unknown or unsupported version number.
Router VRID Errors:
Displays the total number of VRRP packets received with an
invalid VRID for this virtual router.
Statistics
Displays specified virtual router statistics. It lists all the statistics for the specified VRRP group
and can be reset for your convenience when doing statistics.
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VRID:
Displays the VRID associated with your desired VRRP group.
Interface: Displays the Interface ID
associated with your desired VRRP
group.
Checksum Errors: Displays the
number of VRRP packets received with an
invalid VRRP checksum value.
Version Errors:
Displays the number of VRRP packets received with an
unknown or unsupported version number.
State Transitioned
to Master:
Displays the number of times that this virtual
router's state
has transitioned to Master.
Advertisement
Received:
Displays the number of VRRP advertisements received by
this virtual router.
Advertisement
Sent:
Displays the number of VRRP advertisements sent by this
virtual router.
Advertisement
Interval Errors:
Displays the number of the received
VRRP advertisement
packets whose advertisement interval was different from
the one configured for the local virtual router.
Authentication
Failure:
Displays the number of VRRP packets received that did not
pass the authentication check.
IP TTL Errors:
Displays the number of VRRP packets received by the virtual
router with IP TTL (Time-To-Live) not equal to 255.
Zero Priority
Packets Received:
Displays the number of VRRP packets received by the virtual
router with a priority of '0'.
Zero Priority
Packets Sent:
Displays the number of VRRP packets sent by the virtual
router with a priority of '0'.
Invalid Type
Packets Received:
Displays the number of VRRP packets received by the virtual
router with an invalid value in the 'type' field.
Address List Errors:
Displays the number of packets received for which the
address list does not match the locally configured list for the
virtual router.
Invalid
Authentication
Type:
Displays the number of packets received w
ith an unknown
authentication type.
Authentication Type
Mismatch:
Displays the number of packets received with an
authentication type different to the locally configured
authentication method.
Packet Length
Errors:
Displays the number of packets received
with a packet
length less than the length of the VRRP header.
Clear:
Clear the statistics displayed on the web.
Refresh:
Refreshes the web page to show the latest VRRP
information.
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Configuration Procedure
：
Steps Operation Note
1
Configure
interface and
its IP address.
Required. On page Routing → Interface → Interface Config, create
a routing interface (either interface VLAN or routed port) and specify
its IP address and subnet mask.
2
Add port to the
interface.
Required. On page VLAN → 802.1Q VLAN → VLAN Config, add the
port connected to the client to the interface VLAN configured in
Step 1.
3
Configure VRID
and Virtual IP.
Required. On page Routing → VRRP → Basic Config, configure a
VRID and Virtual IP for the interface in Step 1. The Virtual IP and the
interface IP should be on the same LAN. The client should configure
this Virtual IP as the default gateway.
4
Configure the
priority.
Optional. On page Routing → VRRP → Advanced Config, configure
the priority value to be used by the VRRP router in the election for
the master Virtual Router.
5
Configure the
Authentication
Type.
Optional. On page Routing → VRRP → Advanced Config, configure
the authentication type for the Virtual Router.
10.10.6 Application Example for VRRP
Network Requirements
1. Host A needs to access Host B on the Internet. The default gateway of Host A is
192.168.1.10/24.
2. Switch A and Switch B are in the backup group with the Virtual IP address as
192.168.1.10/24.
3. When Switch A works normally, packets sent from Host A to Host B are forwarded by
Switch A. When Switch A is down, packets sent from Host A to Host B are forwarded by
Switch B.
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Network Diagram
Configuration Procedure
Configure Switch A
Steps Operation Note
1
Configure the
interface and
its IP address.
On page Routing → Interface → Interface Config
, create the
interface VLAN2, and configure its IP address as 192.168.1.1 and
Subnet Mask as 255.255.255.0.
2
Add port to the
interface.
On page VLAN → 802.1Q VLAN → VLAN Config, add
the port
connected to the client to interface VLAN 2.
3
Create the
VRRP group
On page Routing → VRRP → Basic Config, create a VRRP group with
the VRID as 1, the interface as VLAN 2 and the Virtual IP as
192.168.1.10.
4
Configure
VRRP priority
On page Routing → VRRP → Advanced Config, configure the VRRP
priority of interface VLAN 2 as 110.
Configure Switch B
Steps Operation Note
1
Configure the
interface and
its IP address.
On page Routing → Interface → Interface Config
, create the
interface VLAN2, and configure its IP address as 192.168.1.2 and
Subnet Mask as 255.255.255.0.
2
Add port to the
interface.
On page VLAN → 802.1Q VLAN → VLAN Config, add
the port
connected to the client to interface VLAN 2.
3
Create the
VRRP group
On page Routing → VRRP → Basic Config, create a VRRP group with
the VRID as
1, the interface as VLAN 2 and the Virtual IP as
192.168.1.10.
Return to CONTENTS
253
Chapter 11 Multicast Routing
Overview of Multicast Routing Protocols
Note
：
The router and router icon mentioned in this chapter represent the router in general or the
switch that runs the layer 3 multicast routing protocols.
The multicast routing protocols run in layer 3 multicast devices and they create and maintain
multicast routes to forward the multicast packets correctly and efficiently. The multicast
routing protocols establish routes for the point-to-multipoint transmissions, known as the
multicast distributing tree.
The multicast routing table consists of a group of (S, G) entries, and (S, G) route represents
routing information from source S to group G. If no multicast source is specified, the entry will
be described as (*, G) with * representing any multicast source. If the router supports multiple
multicast routing protocols, its multicast routing table will contain multicast routes generated
from multiple protocols.
Multicast routing protocols include protocols as IGMP, PIM, MSDP, DVMRP, and static multicast
routing.
The domain mentioned in this guide refers to Autonomous System, which contains a group of
routers exchanging routing information with the same routing protocol.
IGMP stands for Internet Group Management Protocol. It is responsible for members
management of IP multicast in the TCP/IP, and is used to establish and maintain the multicast
member relationships between the IP host and its directly neighboring multicast routers.
PIM (Protocol Independent Multicast) is a typical intra-domain multicast routing protocol
among the AS. It provides IP multicast forwarding by leveraging static routes or unicast routing
tables generated by any unicast routing protocols, such as RIP (Routing Information Protocol),
OSPF (Open Shortest Path First), IS-IS (Intermediate System to Intermediate System) or Border
Gateway Protocol (BGP).
MSDP (Multicast Source Discovery Protocol) is an intra-domain multicast resolution which aims
at the connection of different PIM SM domains and is used to discover the multicast source
information among different ASs.
DVMRP (Distance Vector Multicast Routing Protocol) is mainly applied in the multicast
backbone network of the Internet.
The following mainly introduces IGMP, PIM and Static Multicast Routing.
Multicast Roles and Models
There are several different roles in the multicast transmission：
Multicast Source: The sender of the multicast information.
Multicast Group Member: All the receivers of the multicast information.
Multicast Group: The group consists of the multicast group members.
254
Multicast Router(or the Layer 3 Multicast Device): The router or switch that supports the
layer 3 multicast functions, which contains the multicast routing function and the
management function of the multicast group members.
The multicast model divides into two types depending on whether there is an exact multicast
source: ASM (Any-Source Multicast) and SSM (Source-Specific Multicast).
ASM (Any-Source Multicast): In the ASM model, any sender can be a multicast source sending
multicast information to a multicast group address, and receivers can join a multicast group
identified by the group address and obtain multicast information addressed to that multicast
group. In this model, receivers are not aware of the location of the multicast source in advance.
However, they can join or leave the multicast group at any time. At any specified moment, the
number of multicast source in the ASM should be no more than one, otherwise network
congestion and malfunction of the multicast members may occur.
SSM (Source-Specific Multicast): In the SSM model, the receivers know the exact location of
the multicast source. The SSM allows host to specify the multicast sources and it uses the
multicast group address range different from that of the ASM. The SSM marks a multicast
session with both multicast address and multicast source address, and it builds up dedicated
multicast forwarding path for the receiver and its specified multicast source.
11.1 Global Config
The Global Config can be implemented on the Global Config and Mroute Table pages.
11.1.1 Global Config
You must enable IP multicast routing. Then the software can forward multicast packets, and the
switch can populate its multicast routing table.
Choose the menu Multicast Routing→Global Config→Global Config to load the following
page.
Figure 11-1 Multicast Routing Global Config
The following entries are displayed on this screen:
Multicast Global Config
Multicast Routing:
Enable or disable Multicast Routing function globally on the
switch. The default is "disable".
255
Protocol Mode:
Select PIM DM or PIM SM from the radio button to set the
administrative status in the router. The default is disable.
Protocol State: The
multicast routing protocol presently activated and
operational state of the multicast forwarding module.
Table Maximum
Entry Count:
The maximum number of entries in the IP Multicast routing
table.
Table Entry Count: The number of multicast route entries
currently present in
the Multicast route table.
11.1.2 Mroute Table
On this page you can get the desired mroute information through different search options.
Choose the menu Multicast Routing→Global Config→Mroute Table to load the following
page.
Figure 11-2 Mroute Table
The following entries are displayed on this screen:
Search Option
All:
Select All to display all entries.
Group:
Select Group and enter the group of desired entry.
Source: Select Source and enter the source of desired entry.
Mroute Table
Group:
The destination group IP address.
Source:
The IP address of the multicast packet source to be
combined with the Group IP to fully identify a single route
whose Mroute table entry.
Incoming Interface: T
he incoming interface on which multicast packets for this
source/group arrive.
Uptime: The time in seconds since the entry was created.
Expires:
The time in seconds before this entry will age out and be
removed from the table.
RPF Neighbor: The IP address of the Reverse Path Forwarding neighbor.
256
Protocol:
The multicast routing protocol which created this entry. The
possibilities are PIM DM and PIM SM.
Flags:
The value displayed in this field is valid if the multicast
routing protocol running is PIM SM. The possible values are
RPT or SPT. For other protocols an "------" is displayed.
Detail: Displays the detailed information of the mroute entries.
Outgoing Interface:
Displays the outgoing interfaces on which multicast packets
for this source/group are forwarded.
11.2 IGMP
Brief Introduction of IGMP
IGMP stands for Internet Group Management Protocol. It is responsible for the management of
IP multicast members in IPv4, and is used to establish and maintain the multicast member
relationships between the IP host and its directly neighboring multicast routers.
So far, there are three IGMP versions:
IGMPv1(defined in RFC 1112)
IGMPv2(defined in RFC 2236)
IGMPv3(defined in RFC 3376)
All IGMP versions support ASM model, and IGMPv3 can be directly applied in SSM model.
IGMPv1 Work Mechanism
IGMPv1 is mainly based on the query-and-response mechanism to manage the multicast group
members.
When there are multiple multicast routers in the subnet, all of them can receive IGMP
membership report message. A specific router needs to be chosen from these routers through
the querier election mechanism, and it will works as the querier to send IGMP query message.
In IGMPv1, the DR (Designated Router) is elected according to the multicast routing protocol
(such as PIM) as the exclusive IGMP querier to forward the multicast information.
257
Figure 11-3 IGMP Query-and-Response
As shown in Figure 11-3, Suppose Host B and Host C expect to receive the multicast traffic
sending to multicast group G1, and Host A expects to receive the multicast traffic sending to
multicast group G2. The basic process of the host joining the multicast group and the IGMP
querier (Router B) maintaining the multicast group membership is as below:
(1) Instead of waiting for the IGMP query message from the IGMP querier, the host will actively
send IGMP membership report message to the multicast group it wants to join in.
(2) The IGMP querier will periodically send the IGMP query message to all the hosts and
routers in the local network with the multicast address 224.0.0.1.
(3) After receiving the IGMP query message, the host that is interested in multicast group G1,
either Host B or Host C (depending on whose latency timer runs out first) — for example
Host B, will firstly multicast IGMP membership report message to G1 to declare it belongs
to G1. As all the hosts and routers can receive this membership report message and the
IGMP routers (Router A and Router B) already know there is a host interested in G1, Host C
will not send its report message for G1 after it receives the report message of Host B. This
is called the membership report preventing mechanism and it helps to reduce the traffic in
the local network.
(4) At the same time, as Host A is interested in G2, it will multicast report message to G2 to
declare it belongs to G2.
(5) Through the above query-and-response process, the IGMP router learns that there are
group members of G1 and G2 in the local network. It will generate the multicast forwarding
entries (*, G1) and (*, G2) via the multicast routing protocol, such as PIM, as the basis of the
multicast traffic forwarding. The symbol * represents any multicast source.
(6) When multicast packets sending to G1 or G2 from the multicast source arrive at the IGMP
router via multicast routing, the multicast forwarding entries (*, G1) and (*, G2) in the IGMP
router will guide the multicast packets to the local network and the receiver hosts can
receive them.
258
IGMPv1 doesn’t specially define the leave group message. When a host running IGMPv1 leaves
one multicast group, it wouldn’t send the report message to this multicast group. If no member
exists in the multicast group, the IGMP router will not receive any report message to this
multicast group, thus it will delete this multicast group’s corresponding multicast forwarding
entries after a period of time.
IGMPv2 Work Process
IGMPv2 adds the querier-election mechanism and leave-group mechanism based on IGMPv1.
1. Querier-Election Mechanism
The querier-election mechanism in IGMPv2 is illustrated as below:
(1) Every IGMP router will assume itself as the querier at its initialization, and send IGMP
general query message to all the hosts and routers with the multicast address 224.0.0.1 in
the local network.
(2) After the other IGMPv2 routers in the local network receive this IGMP general query
message, it will compare the message’s source IP address with its interface address.
Through the comparison, the router with the smallest IP address will be elected as the
querier and the other routers as the non-querier.
(3) All the non-queriers will start up a timer, known as the Other Querier Present Timer. This
timer will be reset if the non-querier receives the IGMP query message before the timer
runs out; otherwise the former querier will be assumed as invalid and a new
querier-election will be initiated.
2. Leave-Group Mechanism
When a host leaves a multicast group in IGMPv2:
(1) The host will send leave group message to all the multicast routers in the local network
with the multicast address 224.0.0.2.
(2) After receiving this leave group message, the querier will send group-specific query
message to the multicast group that the host announces to leave. (The querying multicast
group address is filled in the destination address field and the group address field of this
group-specific query message.)
(3) When there are other members of this multicast group in the local network, these
members will send their membership report messages after receiving the group-specific
query message within the max response time set in the query message.
(4) If the querier receives the other member’s membership report message of this multicast
group within the max response time, the querier will continue to maintain the memberships
of this multicast group; otherwise the querier will assume that there is no member in this
multicast group and will no longer maintain its memberships.
259
IGMPv3 Work Process
Compatible of and Inherited from IGMPv1 and IGMPv2, IGMPv3 further enhances the control
capacity of the hosts and broaden the functions of the query and report messages.
1. Enhancement of the Hosts
IGMPv3 adds the filtering mode (INCLUDE/EXCLUDE) for the multicast source basing on the
group-specific query. This mode allows the hosts to accept or reject multicast traffic from
specified multicast sources when joining a multicast group.
When a host joins a multicast group:
If it expects only the multicast data from specified multicast sources, such as S1, S2 … Its
report message can be marked with INCLUDE Sources (S1, S2 …);
If it doesn’t expect any multicast data from the specified multicast sources, such as S2, S2…
Its report message can be marked with EXLUDE Sources (S1,S2 …);
As shown in Figure 11-4, there are two multicast sources, Source 1(S1) and Source 2(S2),
sending multicast data to multicast group G. Host B is only expecting the multicast data
sending from Source 1 to G.
Figure 11-4 IGMPv3 Multicast Source Filtering
If the IGMP protocol running between the hosts and the multicast routers is IGMPv1 or IGMPv2,
Host B will be unable to select its expecting sources when it joins the multicast group G. Thus
whether needed or not, the multicast data from Source 1 and Source 2 will be transferred to
Host B.
When IGMPv3 is running between the hosts and the multicast routers, Host B will only expect
the multicast data sending from Source 1 to G, referred as (S1, G), or refuse to receive the
multicast data sending from Source 2 to G, referred as (S2, G). Thus only the multicast data
from Source 1 will be transferred to Host B.
2. Function Enhancement of the Query and Report Message
260
(1) Query message carrying source address
IGMPv3 supports source-specific query as well as the general query in IGMPv1 and the
group-specific query in IGMPv2:
The general query message carries neither group address nor source address;
The group-specific query message carries the group address without the source address.
The source-specific query message carries not only the group address, but also one or
several source addresses.
(2) The report message carrying several group records
The destination address of IGMPv3 report message is 224.0.0.22. The IGMPv3 report message
can carry one or several group records, which contains the list of multicast group addresses
and multicast source addresses in each of them. The types of group records are listed as
below:
IS_IN: indicating the mapping relationship between the multicast group and the multicast
source list is INCLUDE, which means the host will only receive the multicast data sending
from the specified multicast source list to this multicast group. If the specified multicast
source list is empty here, the host will leave this group.
IS_EX: indicating the mapping relationship between the multicast group and the multicast
source list is EXCLUDE, which means the host will only receive the multicast data sending to
this multicast group with its source not in the specified source list.
TO_IN: indicating the mapping relationship between the multicast group and the multicast
source list changes from EXCLUDE to INCLUDE.
TO_EX: indicating the mapping relationship between the multicast group and the multicast
source list changes from INCLUDE to EXCLUDE.
ALLOW: indicating the host expects to receive multicast data from more multicast sources
besides the current ones. If the current mapping relationship is INCLUDE, these multicast
sources will be added to the multicast source list; if the current mapping relationship is
EXCLUDE, these multicast sources will be deleted from the multicast source list.
BLOCK: indicating the host doesn’t expect to receive multicast data from the specific
multicast sources any longer. If the current mapping relationship is INCLUDE, these
multicast sources will be deleted from the multicast source list; if the current mapping
relationship is EXCLUDE, these multicast sources will be added to the multicast source list.
11.2.1 Global Config
IGMP stands for Internet Group Management Protocol. It is responsible for the management of
IP multicast members in IPv4, and is used to establish and maintain the multicast member
relationships between the IP host and its directly neighboring multicast routers.
Choose the menu Multicast Routing→IGMP→Global Config to load the following page.
261
Figure 11-5 IGMP Global Config
The following entries are displayed on this screen:
Multicast Global Config
Admin Mode:
Select Enable/Disable IGMP function globally on the Switch.
Header Validation: Select Enable/
Disable the validation of igmp header field
Router Alert options. The fields validated for IGMPv2 and
IGMPv3 only. Regardless of whether open the validation,
TTL(Time To Live) must be 1.
11.2.2 Interface Config
Choose the menu Multicast Routing→IGMP→Interface Config to load the following page.
Figure 11-6 Interface Config
The following entries are displayed on this screen:
Search Option
All:
Displays all the interface entries.
Interface VLAN:
Enter the VLAN ID the desired entry must carry.
Routed Port: Enter the routed port the desired entry must carry.
Interface Configuration
Select:
Select the interface for which parameters is to be
configured.
Interface:
The interface for which data is to be displayed or configured.
Admin Mode:
The interface administrative status. You can select
Enable/Disable the IGMP function for the interface.
262
Version: There are three versions for IGMP protocol.
IGMPv1: the interface is now an IGMPv1 Router.
IGMPv2: the interface is now an IGMPv2 Router.
IGMPv3: the interface is now an IGMPv3 Router.
Robustness:
Specify the robustness of the selected interface, ranging
from 1 to 255. The default is 2.
Query Interval: Specify the IGMP query interval at
which IGMP router sends
out a general query, ranging from 1 to 3600.
The default is
125 seconds.
Query Max
Response Time:
When IGMP router sends out a query packet, the host
should response within the specified Query Max Response
Time, the value is in te
nths of a second, ranging from 0 to
255. The default is 100(10 seconds).
Startup Query
Interval:
When IGMP router starts up, it will send out a general query
every Startup Query Interval, ranging from 1 to 300. The
default is 31 seconds.
Startup Query
Count:
The number of general queries to be sent on startup,
ranging from 1 to 20. The default is 2.
Last Member Query
Interval:
When the last member leaves a multicast group, IGMP router
will send out a specific query every Last Member Query
Interval, the v
alue is in tenths of a second, ranging from 0 to
255. The default is 10(1 seconds).
Last Member Query
Count:
The number of queries to be sent on receiving a leave group
report, ranging from 1 to 20. The default is 2.
Profile ID: The Profile ID bound to t
he selected interface, ranging from
0 to 999.The value 0 means bound to none.
11.2.3 Interface State
Choose the menu Multicast Routing→IGMP→Interface State to load the following page.
Figure 11-7 Interface State
The following entries are displayed on this screen:
Search Option
All:
Displays all interface entries.
Interface VLAN:
Enter the VLAN ID the desired entry must carry.
263
Routed Port: Enter the routed port the desired entry must carry.
Interface State
Interface:
The interface for which data is to be displayed or configured.
Operational Status:
The operational state of IGMP on the selected interface.
Querier State:
Indicates whether the selected interface is in querier or
non-querier mode.
IP Address:
The IP address of the selected interface.
Querier IP:
The address of the IGMP querier on the IP subnet to which
the selected interface is attached.
Querier Up Time:
Indicates whether the selected interface is in querier or
non-querier mode.
Querier Expiry
Time:
The time in seconds remaining before the other querier
present timer expires. If the local system is the
querier, this
will be zero.
Wrong Version
Queries Received:
The current number of dynamic groups for the selected
interface.
Number of Joins
Received:
The number of times a group membership has been added
on the selected interface; that is, the number of
times an
entry for this interface has been added to the cache table.
This gives an indication of the amount of IGMP activity on
the interface.
Number of Groups:
The current number of entries for the selected interface in
the cache table.
11.2.4 Multicast Group Table
On this page you can view the information of the multicast groups already on the switch.
Multicast IP addresses range from 224.0.0.1 to 239.255.255.255. The range for receivers to
join is from 224.0.1.0 to 239.255.255.255.
Choose the menu Multicast Routing→IGMP→Multicast Group Table to load the following
page.
Figure 11-8 Multicast Group Table
264
The following entries are displayed on this screen:
Search Option
Search Option: Select the rules for display
ing multicast IP table to find the
desired entries quickly.
All: Displays all multicast IP entries.
Multicast IP:
Enter the multicast IP address the desired
entry must carry.
Interface VLAN
: Enter the VLAN ID the desired entry
must carry.
Routed Port: Sele
ct the routed port the desired entry
must carry.
Multicast Group Table
Interface:
Displays the VLAN ID the desired entry must carry.
Multicast IP:
Displays the multicast IP address the desired entry must
carry.
Operation: Click the Detail button to view
the mode and source IP
address of the multicast group.
11.2.5 Application Example for IGMP
Network Requirements
1. Receivers of different organizations form the stub networks N1 and N2, and Host A and
Host C are the multicast information receivers in N1 and N2 respectively. They receive the
Video-On-Demand information through multicast.
2. In the PIM network, Switch A connects to N1; Switch B and Switch C connect to N2.
3. Switch A connects N1 through its interface VLAN 10, and connects the other devices in
the PIM network through interface VLAN 11.
4. Switch B and Switch C connect to N2 through their interface VLAN 20 respectively. Switch
B connects to the other devices in PIM through interface VLAN 21, and Switch C connects
to the other devices in PIM through interface VLAN 22.
5. IGMPv3 is required between Switch A and N1. IGMPV2 is required among Switch B, Switch
C and N2, with Switch B as the IGMP querier.
265
Network Diagram
Configuration Procedure
1) Configure the interface IP addresses and the unicast routing protocol.
Configure the IP address and subnet mask of each interface as the diagram above. The
detailed configuration steps are omitted here.
Configure the switches to access each other through OSPF protocol. Ensure the network-layer
intercommunication among Switch A, Switch B and Switch C. The dynamic routing information
is updated among the three switches via the unicast routing protocol. The detailed
configuration steps are omitted here.
2) Enable the IP multicast routing, and enable the IGMP function on the interfaces of the
user-side.
Configure Switch A
Steps Operation Note
1
Enable IP
multicast routing.
On page Multicast Routing→ Global Config→ Global Config,
enable the multicast routing function.
2
Enable IGMP on
user-side
interface.
On page Multicast Routing→ IGMP→ Interface Config
, enable
IGMP (version 3) on interface VLAN 10.
Configure Switch B
Steps Operation Note
1
Enable IP
multicast routing.
On page Multicast Routing→ Global Config→ Global Config,
enable the multicast routing function.
266
2
Enable IGMP on
user-side
interface.
On page Multicast Routing→ IGMP→ Interface Config
, enable
IGMP (version 2) on interface VLAN 20.
Configure Switch C
Steps Operation Note
1
Enable IP
multicast routing.
On page Multicast Routing→ Global Config→ Global Config,
enable the multicast routing function.
2
Enable IGMP on
user-side
interface.
On page Multicast Routing→ IGMP→ Interface Config
, enable
IGMP (version 2) on interface VLAN 20.
11.3 PIM DM
In this section we firstly outline PIM protocol, RPF Check mechanism and the two modes of PIM,
then introduce the working process of PIM DM.
PIM is a popular multicast routing protocol within the AS. Instead of relying on one specific
unicast routing protocol, PIM uses the static routing or unicast routing table generated by any
unicast routing protocol (including RIP, OSPF, IS-IS, BGP etc.) to perform routing for IP multicast
data.
Unlike some other multicast routing protocols, PIM doesn’t update routing information between
routers or maintain an independent route forwarding table. PIM uses the RPF (Reverse Path
Forwarding) check mechanism to forward the multicast data.
There are two types of multicast routing and forwarding tables in the multicast implementation:
All the multicast route information will be summarized as a general multicast routing-table;
The multicast forwarding-table is used to control the forwarding of the multicast packets
directly.
The multicast routing table consists of a group of (S, G) entries, and (S, G) route represents
routing information from source S to group G. If the router supports multiple multicast routing
protocols, its multicast routing table will contain multicast routes generated from multiple
protocols. The router will chose the optimal multicast route according to multicast routing and
forwarding strategy, and send it to the multicast forwarding table.
The multicast routing protocol uses the RPF mechanism to establish the multicast routing
entries, thus to guarantee the multicast data being transferred in the correct path.
RPF Mechanism
PIM uses the unicast routing table to perform the RPF check. RPF mechanism ensures the
multicast packets being forwarded correctly according to the multicast routing configuration,
and avoids loops causing by various reasons.
267
1. RPF Check
The RPF check relies on unicast route or static multicast route. The unicast routing table
aggregates the shortest paths to each destination network segments, and the static multicast
routing table lists specified static RPF routing entries configured by the user manually. Instead
of maintaining certain unicast routing independently, the multicast routing protocol relies on
the current unicast routing information or static multicast routing in the network to establish
multicast routing entries.
When performing the RPF check, the router will look up the unicast routing table and the static
multicast routing table at the same time. The process is as below:
(1) Chose an optimal route from the unicast routing table and the static routing table
respectively:
The router looks up the unicast routing table with the IP address of the packet source as the
destination address, and selects an optimal unicast route automatically. The output
interface of the corresponding entry is the RPF interface, and the next hop is the RPF
neighbor. The router will consider the traveling path of the multicast data sent from the RPF
neighbor and received on the RPF interface as the shortest path from the multicast source
S to the local network.
The router looks up the static multicast routing table with the IP address of the packet
source specified as the source address, and selects an optimal static multicast route
automatically. The corresponding entry explicitly specifies the RPF interface and RPF
neighbor.
(2) Select one from the two optimal routes as the RPF route：
According to the longest mask matching principle, the longest mask matching route between
them will be selected; if the two routes have the same mask, the route with higher priority will
be selected; if the two routes also have the same priority, then the static multicast route is prior
to the unicast route.
2. RPF Mechanism Application
When the router receives multicast packets sent from multicast source S to multicast group G,
it will look up the multicast forwarding table at first:
(1) If the corresponding entry (S, G) exists and the packet’s actual arriving interface is the
same as the input interface in the multicast forwarding table, the packet will be forwarded
to all the output interfaces.
(2) If the corresponding entry (S, G) exists and the packet’s actual arriving interface is
different from the input interface in the multicast forwarding table, the router will perform
RPF check on this packet:
If the check result shows that the RPF interface is the same as the input interface in the
current (S, G) entry, which indicates that the (S, G) entry is correct and the packet from the
wrong path will be discarded;
268
If the check result shows that the RPF interface is the different from the input interface in
the current (S, G) entry, which indicates that the (S, G) entry is invalid and the router will
correct the input interface to the packet’s actual arriving interface, and forward this packet
to all the output interfaces.
(3) If the corresponding entry (S, G) doesn’t exist, the router will still perform the RPF check on
this multicast packet. With the RPF interface as the input interface, the router will create
corresponding entry with the RPF interface as the input interface combining related
routing information, and send this entry to the multicast forwarding table:
If the packet’s actual arriving interface is exactly the RPF interface, the RPF check will pass
and the packet will be forwarded to all the output interfaces;
If the packet’s actual arriving interface is not the RPF interface, the RPF check fails and this
packet will be discarded.
PIM Modes
PIM can be divided into two modes according to different routing mechanisms:
PIM DM: Protocol Independent Multicast-Dense Mode
PIM SM: Protocol Independent Multicast-Sparse Mode
PIM DM
PIM DM (defined in RFC 3973) is a multicast routing protocol in dense mode. It uses Push Mode
to transfer multicast packets and applies to small network with relatively dense multicast group
members.
The working mechanism of PIM DM is illustrated as below:
PIM DM assumes that there is at least one multicast group member in each subnet of the
network, and the multicast packets will be flooded to all the nodes in the network. Then
branches without receivers are pruned from the distribution tree, leaving only branches that
contain receivers. This “flood-and-prune” process takes place periodically. The pruned
branches can also resume to forwarding state periodically.
When a new receiver on a previously pruned branch of the tree joins a multicast group, the
PIM DM takes the Graft (see Grafting) mechanism to actively resume this node’s function of
forwarding multicast data, thus reducing the time it takes to resume to the forwarding state.
Generally speaking, the packet forwarding tree in the dense mode is Source Tree (a
forwarding tree with multicast source as the root, and multicast members as the branches).
As the Source Tree is a forwarding tree with the shortest path from the multicast source to
the receivers, it is also called Shortest Path Tree (SPT).
The working process of PIM DM can be summarized as follows：
Neighbor Discovering
SPT Building
Grafting
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Neighbor Discovering
In PIM domain, routers periodically sends PIM Hello packets to all the PIM routers with the
multicast address 224.0.0.13 to discover PIM neighbors, maintain the PIM neighboring
relationships between the routers, thus to build and maintain the SPT.
SPT Building
The SPT building process is also the “flood-and-prune” process:
(1) When the multicast source S is sending multicast packets to multicast group G in PIM DM
domain, the multicast packets will firstly be flooded: After the multicast packet passes the
router’s RPF check, the router will create a corresponding (S, G) entry and forward this
packet to all the nodes downstream in the network. All the routers in the PIM DM domain
will create the (S, G) entry after this flooding process.
(2) Then branches without receivers downstream are pruned. The downstream branches with
no receivers will send prune message to the upstream node to delete the corresponding
interface in the output interface list of the multicast forwarding entry (S, G), and the
multicast packets will no longer forwarded to the pruned branches.
Note
：
The entry (S, G) contains the multicast source address S, the multicast group G, the list of
output interfaces and input interfaces.
The prune process is initiated by the leaf router, as shown in Figure 11-11, the leaf router
without receivers (such as the router directly connected to Host A) performs the prune actively,
and the prune process will last until there are only necessary branches in the PIM DM domain.
These branches form the SPT.
Figure 11-9 SPT Topology in PIM DM
The “flood-and-prune” process takes place periodically. The pruned nodes are provided with
timeout mechanism, and the “flood-and-prune” process will resume after the pruned state
times out.
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Grafting
When a new receiver on a previously pruned branch of the tree joins a multicast group, the PIM
DM takes the Graft mechanism to actively resume this node’s function of forwarding multicast
data, thus reducing the time it takes to resume to the forwarding state. The process is
illustrated as below:
(1) The branch that needs to receive the multicast data again will send a graft message to its
upstream node up the distribution tree towards the source hop-by-hop, applying to rejoin
the SPT;
(2) The upstream node turns the downstream node into forwarding state after receiving the
graft message, and responses with a Graft-Ack message to confirm;
(3) If the downstream node sending the graft message doesn’t receive the Graft-Ack
message from its upstream node, it will keep sending graft messages until being
confirmed.
Assert Mechanism
If there are multiple multicast routers in one network segment, these routers may send the
same multicast packets to this network segment repeatedly. To avoid this kind of situation, the
Assert Mechanism is applied to select the exclusive router to forward the multicast data.
Figure 11-10 Assert Mechanism
As shown in Figure 11-12, the downstream node Router C will receive the same two (S, G)
multicast packets from Router A and Router B in the local network after they receive them from
the upstream nodes. Router A and Router B will also receive the multicast packets on their local
interfaces sent from each other.
Meanwhile, Router A and Router B will send the Assert Messages through their local interfaces
to all the PIM routers with the multicast address 224.0.0.13. The Assert Message contains the
following information: the multicast source address S, the multicast group address G, the
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priority and cost of the unicast route to the multicast source. The router to forward the
multicast packets of (S, G) is elected based on the following rules and in the order listed:
(1) The router with the unicast route of the higher priority to the multicast source;
(2) The router with the unicast route of the smaller cost to the multicast source;
(3) The router with the local interface of the higher IP address.
11.3.1 PIM DM Interface
Choose the menu Multicast Routing→PIM DM→PIM DM Interface to load the following page.
Figure 11-11 PIM DM Interface
The following entries are displayed on this screen:
PIM DM Interface Config
The L3 interfaces can be configured as PIM DM mode by this page.
Select:
Select the desired PIM DM interface entry to modify.
Interface:
The interface for which data is to be displayed or configured.
You must have configured at least one router interface
before configuring or displaying data for a PIM DM interface.
Status: Select enable or disable from the pull-
down list to set the
administrative status of PIM DM for the selected interface.
The default is disable.
Hello Interval:
Specify the rate (time in seconds) at which PIM hello
messages are transmitted from the selec
ted interface. The
valid value ranges from 1 to 18725 and the default is 30
seconds.
DR Priority:
Specify the DR priority for the selected interface. The valid
value range from 0 to 4294967294. The default value is 1.
IP Address:
The IP address of this interface.
Neighbor Count:
The neighbor numbers of this interface.
DR Address:
The designated router on the selected PIM interface.
11.3.2 PIM DM Neighbor
PIM DM neighbor is automatically learned by sending and receiving Hello Packets when PIM DM
is enabled.
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Choose the menu Multicast Routing→PIM DM→PIM DM neighbor to load the following page.
Figure 11-12 PIM DM neighbor
The following entries are displayed on this screen:
Search Option
The L3 interfaces can be configured as PIM DM mode by this page.
Search Option: ALL: Displays all entries.
Neighbor
: Select Neighbor and enter the neighbor
address of your desired entry.
Interface
：Select interface and enter the interface ID of
your desired entry.
PIM DM Neighbor
Interface:
The physical interface on which PIM DM is enabled.
Neighbor:
The IP address of the PIM neighbor for which this entry
contains information.
Uptime:
The time since the PIM neighbor (last) became a neighbor of
the local switch.
Expires:
The time remaining before the PIM neighbor will be aged out.
Configuration Procedure for PIM DM:
Step
Operation
Description
1 Configure
interface
Required. Configure IP addresses and subnet masks of routing
interfaces on Routing→Interface→Interface Config page.
2 Configure routing
protocol
Required.
Configure the routing entries via static route or
dynamic routing protocol like OSPF, and make sure all network
can communicate with each other and update the routing
information through a unicast routing protocol dynamically.
3 Enable multicast
routing and PIM
DM
Required. Enable multicast routing on Multicast Routing→Global
Config page. Enable PIM DM on routing interfaces on Multicast
Routing→PIM DM→PIM DM Interface page.
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Step
Operation
Description
4 Enable IGMP Required. Enable IGMP on the routing interfaces which connect to
the receivers on Multicast Routing→IGMP→Interface Config
page.
11.3.3 Application Example for PIM DM
Network Requirements
1. Receivers receive VOD data through multicast. The whole network runs PIM DM as
multicast routing protocol.
2. Host A and Host D act as multicast receivers.
3. Switch A connects to Switch B in VLAN 2, connects to Switch C in VLAN 3. The Source
server connects to Switch A in VLAN 1.
4. Host A and B connect to Switch B in VLAN 4. Host C and D connect to Switch C in VLAN 5.
5. The VLAN interfaces connecting to hosts run IGMP protocol.
Network Diagram
The IP addresses of VLAN interfaces in each switch are displayed below:
Switch A: VLAN interface 1: 192.168.1.2/24
VLAN interface 2: 192.168.2.2/24
VLAN interface 3: 192.168.3.2/24
Switch B: VLAN interface 2: 192.168.2.100/24
VLAN interface 4: 192.168.4.100/24
Switch C: VLAN interface 3: 192.168.3.100/24
VLAN interface 5: 192.168.5.100/24
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Configuration Procedure
Configure Switch A:
Step
Operation
Description
1 Configure interface. Configure IP addresses and subnet masks of VLAN interfaces 1, 2
and 3 on Routing→ Interface→Interface Config page.
2 Configure routing
protocol.
Configure the routing entries via static route or dynamic routing
protocol like OSPF, and make sure all the switches can
communicate with each other and update the routing information
through a unicast routing protocol dynamically.
3 Enable multicast
routing and PIM DM
Enable multicast routing on Multicast Routing→Global Config
page. Enable PIM DM on VLAN interfaces 1, 2 and 3 on Multicast
Routing→PIM DM→PIM DM Interface page.
Configure Switch B and C:
Step
Operation
Description
1 Configure
interface
Configure IP addresses and subnet masks of VLAN interfaces 2,
3, 4 and 5 on Routing→Interface→Interface Config page.
2 Configure routing
protocol
Configure the routing entries via static route or dynamic routing
protocol like OSPF, and make sure all network can communicate
with each other.
3 Enable multicast
routing and PIM
DM
Enable multicast routing on Multicast Routing→Global Config
page. Enable PIM DM on VLAN interfaces 2, 3, 4 and 5 on
Multicast Routing→PIM DM→PIM DM Interface page.
4 Enable IGMP Enable IGMP on the VLAN interfaces 4 and 5 which connect to the
receivers on Multicast Routing→IGMP→Interface Config page.
11.4 PIM SM
PIM DM uses the “flood-and-prune” mode to create the SPT for transferring multicast data.
Although SPT has the short path, its building-up process is of low efficiency and does not apply
to the large and medium-sized network.
PIM SM is a multicast routing protocol in sparse mode. It uses the “Pull Mode” to transfer
multicast data and usually applies to large and medium-sized network with relatively sparse
multicast group members.
The working mechanism of PIM SM is illustrated as below:
PIM SM assumes that no hosts need to receive the multicast data, the multicast data will not
be forwarded to the host unless there is an explicitly request for the traffic. The core task of
PIM SM to realize multicast forwarding is to build and maintain the RPT (Rendezvous Point
Tree). RPT selects a certain router in the PIM domain as the public RP (rendezvous point),
through which the multicast data is transferred along the RPT to the receivers.
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The router connected to the receiver sends the join message to the RP of a certain multicast
group. The path along which the join message is sent to the RP hop-by-hop forms a branch
of RPT.
When the multicast source is sending multicast data to a multicast group, the router directly
connected to the multicast source firstly registers to the RP by sending the Register
Message to the RP in unicast mode. The arrival of the register message at the RP triggers
the establishment of the SPT. Then the multicast source sends the multicast data along the
SPT to the RP. The multicast data will be duplicated and distributed to the receivers after
they arrive at the RP.
Note:
The duplicating process only takes place at the branching point of the distributing tree, and this
process automatically repeats until the packets arrives at the final receivers.
The work process of PIM SM can be generalized below:
Neighbor Discovering
DR Electing
RP Discovering
RPT Building
Multicast Source Registering
Switching from RPT to SPT
Asserting
Neighbor Discovering
The neighbor discovering mechanism of PIM SM and PIM DM is the same, for more details,
refer to Neighbor Discovering.
DR Electing
The DR (Designated Router) in the shared network is elected through the Hello message, and
works as the exclusive router to forward multicast data in this shared network.
Whether the network connects to the multicast source or the network connects to the
receivers, the DR must be elected if the network is a shared one. The DR is responsible for
sending join message to the RP in the receiver side and sending register message to the RP in
the multicast source side.
Note:
The DR is elected between the multiple routers of the network segment by comparing the
priorities and IP addresses carried in Hello packets. The elected DR has practical meaning
in PIM SM; with PIM DM operation, the DR has meaning only if IGMPv1 is in use, the elected
DR functions as the IGMP querier on account that IGMPv1 does not have an IGMP querier
election process.
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The device working as DR should be enabled with the IGMP function; otherwise the
receivers connected to it would be unable to join the multicast group via this DR.
Figure 11-13 DR Elect
As shown in Figure 11-15, the DR election process is illustrated below:
(1) Routers in the shared network sends Hello message carrying DR-election priority to each
other, and the router with the highest priority will be elected as the DR;
(2) If the routers have the same priorities, or at least one route in the network doesn’t support
carrying the DR-election priority in the Hello packet, the routers with the highest IP
address will be elected as the DR.
When the DR fails, a new DR election process will be triggered if the other routers haven’t
received the hello packet from the DR before they time out.
RP Discovering
RP is the core device in the PIM SM domain. In a small network with simple structure, the
multicast data is so little that merely one RP is enough to forward it. In this network an RP can
be statically designated among the routers in the PIM SM domain; in more circumstances, the
PIM SM domain is of large scale and the forwarding data for the RP is huge. To release the
burden of the RP and optimize the RPT topology, each multicast group should have its own RP.
Thus the bootstrapping mechanism is needed to elect the RP dynamically. The BSR (BootStrap
Router) should be configured in this mechanism.
BSR is the administrative core in the PIM SM. It collects the Advertisement Messages sent from
the C-RP (Candidate-RP) in the network and selects certain C-RP information to compose a
RP-Set (which is the mapping relationship database between the multicast group and the RP).
The RP-Set is published to the whole PIM SM domain and all the routers (including DR) can
calculate the required RP location according to the information offered by the RP-Set.
In a PIM SM domain (or administrative domain), there is only one BSR (for more details about
BSR administrative domain, please refer to BSR Adminsitrative Domain) and several C-BSRs
(Candidate-BSR). Once the BSR fails, a new BSR will be elected among the other C-BSRs to
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avoid business disruption. Similarly, several C-RPs can be configured in one PIM SM domain,
and each multicast group’s corresponding RP can be calculated through the BSR mechanism.
The location of RP and BSR in the network is shown below:
Figure 11-14 The Locations of C-RP, C-BSR and BSR
RPT Building
Figure 11-15 RPT Topology in PIM SM
As shown in Figure 11-17, the establishing process of RPT is illustrated below:
(1) When a receiver joins a multicast group G, it informs the directly connected DR with IGMP
message;
(2) After receiving the IGMP message from multicast group G, the DR sends PIM join message
toward the corresponding root, also known as the RP;
(3) The join message travels router-by-router toward the root, constructing a branch of the
RPT as it goes. These routers generate (*, G) entries in their forwarding tables with *
representing any multicast source. The RPT works with RP as the root node, and DR as the
branch node.
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When multicast data for multicast group G is sent to RP, it will travels along the constructed
RPT to DR and finally arrives at the receivers.
When a receiver is no longer interested in the multicast group data, its directly connected DR
will send prune message up the RPT toward the group’s corresponding RP; after the upstream
node receives this prune message, it will delete the link to the downstream node in its interface
list and check if there are other receivers of this group. If there are no more receivers, the
prune message will be sent upstream.
Multicast Source Registering
The multicast source register is to inform its presence to the RP.
As shown in Figure 11-18, the process of the multicast source registering to RP is illustrated
below:
Figure 11-16 Multicast Source Register Topology in PIM SM
(1) When the multicast source S’s directly connected DR receives a multicast packet sent
from the multicast source to the multicast group G, the DR will encapsulate this packet into
a register packet and send it to the corresponding RP in unicast way;
(2) After the RP receives the register packet, it will de-capsulate this packet and send the
packaged multicast data to the receivers along the RPT, and meanwhile it will send join
message to the multicast source hop-by-hop. The join message travels router-by-router
toward the source from the RP, constructing a branch of the SPT as it goes. These routers
generate (S, G) entries in their forwarding tables. The SPT works with multicast source as
the root, and RP as the branch.
(3) The multicast data sent from the multicast source travels along the constructed SPT to RP,
and is forwarded by the RP to the receivers along the RPT. When RP receives the multicast
data from the RPT, it will send Register-Stop Message to the DR directly connected to the
multicast source to finish the multicast source register process.
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Switching from RPT to SPT
Once receiver-side DR receives the multicast data from RP to multicast group G, the switching
process from RPT to SPT will be triggered:
(1) The receiver-side DR sends (S, G) join message to the multicast source S hop-by-hop, and
the join message finally arrives at the source-side DR. All routers the join message passes
will generate the (S, G) entry in their forwarding tables, thus building up a branch of SPT;
(2) The receiver-side DR sends prune message toward the RP hop-by-hop. The RP will
forward the received prune message toward the multicast source. The switching process
from RPT to SPT is then accomplished.
After the switching from RPT to SPT, the multicast data will be sent from multicast source to
the receivers directly. Through this switching process from RPT to SPT, PIM SM constructs the
SPT in a more economical way than PIM DM does.
Asserting
The assert mechanism of PIM SM and PIM DM is the same. For more details, refer to Assert
Mechanism.
BSR Administrative Domain
BSR is the administrative core in the PIM SM domain. The BSR is exclusive in one PIM SM
domain and it advertises the RP-Set information in the whole PIM SM domain. All the multicast
group information is forwarded inside the BSR’s administrative network scope. When the PIM
SM domain is relatively large, you can consider dividing the PIM SM domain into multiple BSR
administrative domains, thus sharing the administrative pressure of single BSR and providing
specialized services for specific multicast groups.
In geographical space, the BSR administrative domains are separated with each other and one
router cannot belong to more than one BSR domain. In other words, the routers contained by
the BSR domains are different from each other.
In multicast address, each BSR administrative domain provides services for specific multicast
groups. These multicast group addresses usually have no intersection with each other, but
they may also have crossings and overlaps, as shown in Figure 11-19.
Figure 11-17 BSR Domain Divided by Multicast Address
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Features of BSR administrative domain:
Divide the BSR administrative domains by setting BSR border
Each BSR administrative domain has its own border, C-RP and BSR devices. These devices are
only valid in their belonged domains, which means that the BSR mechanism and RP election are
separated between their administrative domains.
BSR messages cannot pass through the BSR border
The multicast messages (such as C-RP Hello Message and BSR BootStrap Message) of each
BSR administrative domain cannot pass through the domain border.
11.4.1 PIM SM Interface
Choose the menu Multicast Routing→PIM SM→PIM SM Interface to load the following page.
Figure11-18 PIM SM Interface
The following entries are displayed on this screen:
PIM SM Interface Config
The L3 interfaces can be configured as PIM SM mode by this page.
Select:
Select the desired interface to configure.
Interface:
Displays the VLAN interface which you can configure.
Status:
Select to enable or disable PIM SM function on the interface.
Hello Interval: Specify the rate (time in seco
nds) at which PIM hello
messages are transmitted from the selected interface. The
valid value ranges from 1 to 18725 seconds and the default
is 30 seconds.
Join/Prune Interval:
Specify the frequency at which PIM Join/Prune messages
are transmitted on this
PIM interface. The valid value range
from 1 to 18724 seconds and the default value is 60
seconds.
DR Priority:
Specify the DR priority for the selected interface. The valid
value range from 0 to 4294967294. The default value is 1.
BSR Border: Select to
enable or disable the BSR border to define a PIM
bootstrap message boundary for the PIM domain.
IP Address:
Displays the IP address of the interface.
Neighbor Count:
Displays the number of PIM neighbors of this interface.
DR Address
Displays the DR address of the interface.
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11.4.2 PIM SM Neighbor
PIM SM neighbor is automatically learned by sending and receiving Hello Packets when PIM SM
is enabled.
Choose the menu Multicast Routing→PIM SM→PIM SM Neighbor to load the following page.
Figure 11-19 PIM SM neighbor
The following entries are displayed on this screen:
Search Option
Search Option: ALL: Displays all entries.
Neighbor: Select Neighbor and enter the neighbor
address of your desired entry.
Interface: Selec
t Interface VLAN and enter the interface
ID of your desired entry.
Interface Routed Port: Select Interface Routed Port and
enter the interface ID of your desired entry.
PIM SM Neighbor
Interface:
The physical interface on which PIM DM is enabled.
Neighbor:
The IP address of the PIM neighbor for which this entry
contains information.
Uptime:
The time since the PIM neighbor (last) became a neighbor of
the local switch.
Expires:
The time remaining before the PIM neighbor will be aged out.
11.4.3 BSR
PIM SM uses a Bootstrap Router (BSR), which advertises information to other multicast routers
about the rendezvous point (RP). In a given network, a set of routers can be administratively
enabled as candidate bootstrap routers(C-BSR). If it is not apparent which router should be the
BSR, the candidates flood the domain with advertisements. The router with the highest priority
is elected. If all the priorities are equal, then the candidate with the highest IP address becomes
the BSR.
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Choose the menu Multicast Routing→PIM SM→BSR to load the following page.
Figure 11-20 BSR
The following entries are displayed on this screen:
PIM SM Candidate BSR Config
Configure the candidate BSR of current device.
Interface: Select the in
terface on this switch from which the BSR
address is derived to make it a candidate. This interface
must be enabled with PIM SM.
Hash Mask Length:
specify the mask length that is to be ANDed with the group
address before the hash function is called. All g
roups with
the same seed hash correspond to the same RP The valid
value range from 0 to 32 and the default value is 30.
Priority:
Specify the priority of the BSR. The BSR with the larger
priority is preferred. If the priority values are the same, the
devi
ce with the highest IP address is selected as the BSR.
The valid value range from 0 to 255 and the default value is
64.
Interval:
The BSR Advertisement interval, ranging from 1 to 16383.
PIM SM Elected BSR Information
BSR Address:
Displays the elected BSR address.
Priority:
Displays the priority of the elected BSR.
Hash Mask Length:
Displays the hash mask length of the elected BSR.
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Next BSR message
time:
Displays the time of next BSR message sending if this is the
elected BSR.
Expire:
Displays the expiry time of the elected BSR.
PIM SM Candidate BSR Information
Candidate BSR
Address:
Displays the Candidate BSR address.
Priority:
Displays the priority of the Candidate BSR.
Hash Mask Length: Displays the hash mask length of the Candidate BSR.
11.4.4 RP
In the PIM SM mode, RP receives multicast data from the source and transmits the data down
the shared tree to the multicast group members. You must have an RP if the interface is in
sparse-dense mode, and you can manually assign static RP or config candidate RP to generate
the RP.
Choose the menu Multicast Routing→PIM SM→RP to load the following page.
Figure 11-21 RP Config
The following entries are displayed on this screen:
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PIM SM Static RP Config
By default, no static RP address is configured. You could configure the IP address of RPs on all
multilayer switches.
RP Address:
Specify the IP address of the static RP.
Group:
Group Address of the RP to be created or deleted.
Group Mask:
Group Mask of the RP to be created or deleted.
Override:
Select to enable or disable override mode. If the override
mode is enabled, the static RP will take effect no matter the
candidate RP is configured or not. Otherwise the static RP
will be invalid when the candidate RP is configured.
PIM SM Static RP Table
Displays the configured static RP of this PIM SM domain.
RP Address:
Displays the ip address of static RP.
Group:
Displays the group address.
Group Mask:
Displays the group mask.
Override: Displays the override mode. If
the override mode is enabled,
the static RP will take effect no matter the candidate RP is
configured or not. Otherwise the static RP will be invalid
when the candidate RP is configured.
PIM SM Candidate RP Config
Configure the candidate RP on this device. Candidate RPs periodically send multicast
RP-announce messages to a particular group or group range to announce their availability.
Interface:
Select the VLAN interface of the candidate RP.
Group: The group address transmitted in Candidate-RP-
Advertisements.
Group Mask: The group address mask transmitted in Candidate-RP-
Advertisements.
Interval:
Specify the interval of advertisement message of the
candidate RP in seconds. The default value is 60.
PIM SM Candidate RP Table
Interface:
Displays the VLAN interface of the candidate RP.
Group:
Displays the group address transmitted in
Candidate-RP-Advertisements.
Group Mask:
Displays the group address mask transmitted in
Candidate-RP-Advertisements.
Interval: Displays the interval of advertisement messa
ge of the
candidate RP in seconds.
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Next advertisement
time:
Displays the remaining time to send the next RP
advertisement packet.
11.4.5 RP Mapping
Choose the menu Multicast Routing→PIM SM→RP Mapping to load the following page.
Figure 11-22 RP Mapping
The following entries are displayed on this screen:
Search Option
Search Option: ALL: Select All to display all entries.
RP
: Select RP and enter the RP IP address of desired
entry.
Group to RP Mappings Information
Group:
Displays the group address.
RP:
Displays the RP address.
Info Source:
Displays the BSR address which announce the RP
information.
Holdtime:
Displays the holdtime of the RP.
Expires
Displays the expiry time of the RP. If RP is static, the expiry
time will be Never.
11.4.6 RP Info
Choose the menu Multicast Routing→PIM SM→RP Info to load the following page.
Figure 11-23 RP Info
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The following entries are displayed on this screen:
Search Option
Search Option: ALL: Select All to display all entries.
Group
: Select Group and enter the group IP address of
desired entry.
RP Information
Group:
Displays the group address.
RP:
Displays the RP address.
Configuration Procedure for PIM SM:
Step
Operation
Description
1 Configure
interface.
Required. Configure
IP addresses and subnet masks of routing
interfaces on Routing→ Interface→Interface Config page.
2 Configure routing
protocol.
Required. Configure the routing entries via static route or dynamic
routing protocol like OSPF, and make sure all the switches can
communicate with each other and update the routing information
through a unicast routing protocol dynamically.
3 Enable multicast
routing and PIM
SM.
Required. Enable multicast routing on Multicast Routing→Global
Config page. Enable PIM SM on routing interfaces on Multicast
Routing→PIM SM→PIM SM Interface page.
4 Configure static
RP or configure
candidate BSR
and candidate RP.
Required. Configure static RP or configure a specified routing
interface as candidate RP on Multicast Routing→PIM SM→RP page.
Configure a specified routing interface as candidate BSR on
Multicast Routing→PIM SM→BSR page.
5 Enable IGMP. Required. Enable IGMP on the routing interfaces which connect to
the receivers on Multicast Routing→IGMP→Interface Config page.
11.4.7 PIM SSM
While PIM-SM employs a specially-configured RP router that serves as a meeting junction for
multicast senders and listeners, Protocol-Independent Multicast Source Specific Multicast
(PIM-SSM) does not use an RP. It supports only source-route deliver trees. It is used between
routers so that they can track which multicast packets to forward to each other and to their
directly-connected LANs. The SSM service model can be implemented with a strict subset of
the PIM-SM protocol mechanisms. Both regular IP Multicast and SSM semantics can coexist on
a single router and both can be implemented using the PIM-SM protocol. A range of multicast
addresses, currently 232.0.0.0/8 in IPv4, is reserved for SSM.
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Choose the menu Multicast Routing→PIM SM→PIM SSM to load the following page.
Figure 11-24 PIM SSM Config
The following entries are displayed on this screen:
PIM SSM Config
Group:
Enter the source-specific multicast group ip-address.
Group Mask:
Enter the source-specific multicast group ip-address mask.
PIM SSM Config Table
Select:
Enter the source-specific multicast group ip-address.
Group:
Displays the source-specific multicast group ip-address.
Group Mask: Displays the source-specific multicast group ip-address
mask.
11.4.8 Packet Statistics
Choose the menu Multicast Routing→PIM SM→Packet Statistics to load the following page.
Figure 11-25 Packet Statistics
The following entries are displayed on this screen:
Auto Refresh
Auto Refresh:
Select Enable/Disable auto refresh feature.
Refresh Period:
Enter the time from 3 to 300 in seconds to specify the auto
refresh period.
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PIM SM Statistics
Interface:
The interface on which PIM SM is enabled.
Stat: Rx: Packet Received in Protocol.
Tx: Packet Sent from Protocol.
Hello:
Hello Format Packets Statistics.
Register:
Register Format Packets Statistics.
Reg-Stop:
Register-Stop Format Packets Statistics.
Join/Pru:
Join/Prune Format Packets Statistics.
BSR:
Bootstrap Format Packets Statistics.
Assert:
Assert Format Packets Statistics.
CRP:
Candidate-RP-Advertisement Format Packets Statistics.
Error Packet:
Err Packets Statistics.
11.4.9 Application Example for PIM SM
Network Requirements
1. Receivers receive VOD data through multicast. The whole network runs PIM SM as
multicast routing protocol.
2. Host A and Host D act as multicast receivers.
3. Switch A connects to Switch B in VLAN 2, connects to Switch C in VLAN 3. The Source
server connects to Switch A in VLAN 1.
4. Host A and B connect to Switch B in VLAN 4. Host C and D connect to Switch C in VLAN 5.
5. All switches run PIM SM. The VLAN interfaces connected to hosts run IGMP protocol.
6. Specify VLAN interface 3 in switch A as candidate BSR and candidate RP.
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Network Diagram
The IP addresses of VLAN interfaces in each switch are displayed below:
Switch A: VLAN interface 1: 192.168.1.2/24
VLAN interface 2: 192.168.2.2/24
VLAN interface 3: 192.168.3.2/24
Switch B: VLAN interface 2: 192.168.2.100/24
VLAN interface 4: 192.168.4.100/24
Switch C: VLAN interface 3: 192.168.3.100/24
VLAN interface 5: 192.168.5.100/24
Configuration Procedure
Configure Switch A:
Step
Operation
Description
1 Configure interface. Configure IP addresses and subnet masks of VLAN interfaces
1, 2 and 3 on Routing→ Interface→Interface Config page.
2 Configure routing
protocol.
Configure the routing entries via static route or dynamic routing
protocol like OSPF, and make sure all the switches can
communicate with each other and update the routing
information through a unicast routing protocol dynamically.
3 Enable multicast
routing and PIM SM.
Enable multicast routing on Multicast Routing→Global Config
page. Enable PIM SM on VLAN interfaces 1, 2 and 3 on
Multicast Routing→PIM SM→PIM SM Interface page.
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4 Configure candidate
BSR and candidate
RP.
Configure VLAN interface 1 as candidate BSR on Multicast
Routing→PIM SM→BSR pa
ge. Configure VLAN interface 1 as
candidate RP on Multicast Routing→PIM SM→RP page.
Configure Switch B and C:
Step
Operation
Description
1 Configure interface. Configure IP addresses and subnet masks of VLAN interfaces
2, 3, 4 and 5 on Routing→ Interface→Interface Config page.
2 Configure routing
protocol.
Configure the routing entries via static route or dynamic routing
protocol like OSPF, and make sure all network can
communicate with each other.
3 Enable multicast
routing and PIM SM.
Enable multicast routing on Multicast Routing→Global Config
page. Enable PIM SM on VLAN interfaces 2, 3, 4 and 5 on
Multicast Routing→PIM SM→PIM SM Interface page.
4 Enable IGMP. Enable IGMP on the VLAN interfaces 4 and 5 which connect to
the receivers on Multicast Routing→IGMP→Interface Config
page.
11.5 Static Mroute
When the multicast network topology is the same as that of the unicast network, receivers can
receive the multicast data through the unicast route. But in some circumstances, the multicast
network topology differs from that of unicast network or some routers in the network supports
unicast only. Then you can configure static multicast routes to offer different transferring paths
for multicast and unicast data separately. Notice the following two considerations:
The static multicast routing functions only to affect the RPF check, but not to direct the
forwarding of the multicast data, so it is also called RPF static routing;
The static multicast routing only functions in the configured multicast router. It won’t be
broadcasted or imported into other routers in any way.
The static multicast routing is an important foundation for the RPF check. In the RPF check
process, with static multicast routing configured, the router will choose one as the RPF route
after comparing the optimal unicast route and the static multicast route selected respectively
from the unicast routing table and the static multicast routing table.
291
Figure 11-26 Static Multicast Routing
As shown in Figure 11-26, when no static multicast routing entry is configured, the RPF
neighbor of Router C to the multicast source is Router A. The multicast packets sent from
Source will be transferred along the path Router A→Router C, which is the same as the unicast
path. When Router C is configured with static multicast routing and the RPF neighbor of Router
C to Source is configured as Router B, the multicast data sent from Source will travel along a
different path Router A→Router B→Router C.
11.5.1 Static Mroute Config
Choose the menu Multicast Routing→Static Mroute→Static Mroute Config to load the
following page.
Figure 11-27 Static Mroute Config
292
The following entries are displayed on this screen:
Static Mroute Config
Source:
Enter the IP address that identifies the multicast source of
the entry you are creating.
Source Mask:
Enter the subnet mask to be applied to the Source.
RPF Neighbor: Enter the IP address of the neighbor r
outer on the path to
the mroute source.
Distance:
Enter the Administrative distance of static mroute. The
range is 0-
255 and default is 0. The lower the distance, the
better the preference.
Static Mroute Config Table
Select：
Select the static mroute entry to modify.
Source:
Displays the IP address of the multicast source.
Source Mask:
Displays the subnet mask of source.
RPF Neighbor:
Displays the IP address of the neighbor router.
Distance:
Displays the Administrative distance of static mroute.
Click delete to delete the selected entry.
11.5.2 Application Example for Static Mroute
Network Requirements
1. The network runs PIM DM and all the switches in the network support multicast features.
2. Switch A, Switch B and Switch C run OSPF protocol.
3. In normal circumstances, Receiver receives multicast data from Source through the path
Switch A-Switch B, which is the same as the unicast route.
4. After the configuration takes effect, Receiver will receive multicast data from Source
through the path Switch A-Switch C-Switch B.
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Network Diagram
Configuration Procedure
1) Configure the interfaces and unicast routing protocol
Configure the VLAN interfaces and their IP addresses of Switch A, Switch B and Switch C on
the page Routing→ Interface→ Interface Config according to the topology,
Configure the OSPF features on the switches in this PIM DM domain, making the switches
accessible with each other at the network layer. Detailed configuration process is omitted here.
2) Configure the multicast routing features
Configure Switch A
Step Operation Note
1
Enable IP
multicast routing
Required. On page Multicast Routing→Global Config→Global
Config, enable the Multicast Routing function globally.
2
Enable PIM DM Required. On page Multicast Routing→PIM DM→
PIM DM
Interface
, enable PIM DM on the VLAN interfaces 102, 103 and
200.
Configure Switch B
Step Operation Note
1
Enable IP
multicast routing
Required. On page Multicast Routing→Global Config→Global
Config, enable the Multicast Routing function globally.
2
Enable PIM DM Required. On page Multicast Routing→PIM DM→
PIM DM
Interface, enable PIM DM on the VLAN interfaces 100,
101 and
102.
294
Step Operation Note
3
Enable IGMP Required. On page Multicast Routing→IGMP→Interface Config,
enable the IGMP function on VLAN interface 100.
4
Configure static
multicast routing
Required. On page Multicast Routing→Static Mroute→Static
Mroute Config, configure a static multicast routing entry with the
Source as 50.1.1.100, the Source Mask as 255.255.255.0 and the
RPF Neighbor as 20.1.1.2.
Configure Switch C
Step Operation Note
1
Enable IP
multicast
routing
Required. On page Multicast Routing→Global Config→Global
Config, enable the Multicast Routing function globally.
2
Enable PIM DM Required. On page Multicast Routing→PIM DM→PIM DM Interface,
enable PIM DM on the VLAN interfaces 101 and 103.
3) Verify the configuration
On page Multicast Routing→Global Config→Mroute Table on Switch A, check the RPF
neighbor of the entry whose Source is 50.1.1.100/24. The RPF neighbor should be 20.1.1.2 (the
interface on Switch C) if the configuration is valid.
Return to CONTENTS
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Chapter 12 QoS
QoS (Quality of Service) functions to provide different quality of service for various network
applications and requirements and optimize the bandwidth resource distribution so as to
provide a network service experience of a better quality.
QoS
This switch classifies the ingress packets, maps the packets to different priority queues and
then forwards the packets according to specified scheduling algorithms to implement QoS
function.
Figure 12-1 QoS function
Traffic classification: Identifies packets conforming to certain characters according to
certain rules.
Map: The user can map the ingress packets to different priority queues based on the
priority modes. This switch implements three priority modes based on port, on 802.1P and
on DSCP.
Queue scheduling algorithm: When the network is congested, the problem that many
packets compete for resources must be solved, usually in the way of queue scheduling.
The switch supports three schedule modes: SP, WRR and SP+WRR.
Priority Mode
This switch implements three priority modes based on port, on 802.1P and on DSCP. By default, the
priority mode based on port is enabled and the other two modes are optional.
1. Port Priority
Port priority is just a property of the port. After port priority is configured, the data stream will
be mapped to the egress queues according to the CoS of the port and the mapping
relationship between CoS and queues.
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2. 802.1P Priority
Figure 12-2 802.1Q frame
As shown in the figure above, each 802.1Q Tag has a Pri field, comprising 3 bits. The 3-bit
priority field is 802.1p priority in the range of 0 to 7. 802.1P priority determines the priority of
the packets based on the Pri value. On the Web management page of the switch, you can
configure different priority tags mapping to the corresponding priority levels, and then the
switch determine which packet is sent preferentially when forwarding packets. The switch
processes untagged packets based on the default priority mode.
3. DSCP Priority
Figure 12-3 IP datagram
As shown in the figure above, the ToS (Type of Service) in an IP header contains 8 bits. The first
three bits indicate IP precedence in the range of 0 to 7. RFC2474 re-defines the ToS field in the
IP packet header, which is called the DS field. The first six bits (bit 0-bit 5) of the DS field
indicate DSCP precedence in the range of 0 to 63. The last 2 bits (bit 6 and bit 7) are reserved.
On the Web management page, you can configure different DS field mapping to the
corresponding priority levels. Non-IP datagram with 802.1Q tag are mapped to different priority
levels based on 802.1P priority mode if 8021.1P Priority mode is enabled; the untagged non-IP
datagram are mapped based on port priority mode.
Schedule Mode
When the network is congested, the problem that many packets compete for resources must
be solved, usually in the way of queue scheduling. The switch implements seven scheduling
queues, ranging from TC0 to TC6. TC0 has the lowest priority while TC6 has the highest priority.
The switch supports three schedule modes: SP, WRR and SP+WRR.
1. SP-Mode: Strict-Priority Mode. In this mode, the queue with higher priority will occupy the
whole bandwidth. Packets in the queue with lower priority are sent only when the queue
with higher priority is empty. The switch has eight egress queues labeled as TC0, TC1,
TC2 …TC6. In SP mode, their priorities increase in order. TC6 has the highest priority. The
disadvantage of SP queue is that: if there are packets in the queues with higher priority for
a long time in congestion, the packets in the queues with lower priority will be “starved to
death” because they are not served.
297
Figure 12-4 SP-Mode
2. WRR-Mode: Weight Round Robin Mode. In this mode, packets in all the queues are sent in
order based on the weight value for each queue and every queue can be assured of a
certain service time. The weight value indicates the occupied proportion of the resource.
WRR queue overcomes the disadvantage of SP queue that the packets in the queues with
lower priority cannot get service for a long time. In WRR mode, though the queues are
scheduled in order, the service time for each queue is not fixed, that is to say, if a queue is
empty, the next queue will be scheduled. In this way, the bandwidth resources are made full
use of. The default weight value ratio of TC0, TC1, TC2, TC3, TC4, TC5 and TC6 is
1:2:3:4:5:6:7.
Figure 12-5 WRR-Mode
3. SP+WRR-Mode: Strict-Priority + Weight Round Robin Mode. In this mode, this switch
provides two scheduling groups, SP group and WRR group. Queues in SP group and WRR
group are scheduled strictly based on strict-priority mode while the queues inside WRR
group follow the WRR mode. In SP+WRR mode, TC6 is in the SP group; TC0, TC1, TC2 to
TC5 belong to the WRR group and the weight value ratio of TC0, TC1, TC2 to TC6 is
1:2:3:4:5:6:7. In this way, when scheduling queues, the switch allows TC6 to occupy the
whole bandwidth following the SP mode and the TC0, TC1, TC2 to TC5 in the WRR group
will take up the bandwidth according to their ratio 1:2:3:4:5:6.
The QoS module is mainly for traffic control and priority configuration, including five submenus:
Class of Service, DiffServ, Bandwidth Control, Voice VLAN and Auto VoIP.
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12.1 Class of Service
The Class of Service (CoS) queueing feature allows you configure certain aspects of switch
queueing. It provides the desired QoS behavior for different types of network traffic when the
complexities of DiffServ are not required. This switch classifies the ingress packets, maps the
packets to different priority queues and then forwards the packets according to specified
scheduling algorithms. The switch implements three priority modes based on port, on 802.1P
and on DSCP, and supports three queue scheduling algorithms.
The Class of Service function can be implemented on Trust Mode, Port Priority, 802.1P/CoS
to Queue Mapping, DSCP to Queue Mapping and Schedule Mode pages.
12.1.1 Trust Mode
On this page you can configure the trust mode. The switch can be configured to trust one of
the packet fields (802.1p or IP DSCP), or to not trust any packet’s priority designation
(untrusted mode).
Choose the menu QoS→Class of Service→Trust Mode to load the following page.
Figure 12-6 Port Priority Config
Configuration Procedure:
Configure the trust mode according to your needs, then click Apply.
Entry Description:
Trust Mode: Configure the trust mode.
untrusted:
untrusted mode. In this mode, data will be classified into
different service based on the port priority and the 802.1p
/CoS
mapping.
trust 802.1p: trust 802.1p mode. In this mode, data will be classified
into dif
ferent service based on the 802.1p priority and the
802.1P/CoS mapping.
trust ip-dscp: trust ip-
dscp mode. In this mode, data will be
classified into different service based on the DSCP
priority and the
DSCP-mapping.
12.1.2 Port Priority
On this page you can configure the port priority.
Choose the menu QoS→Class of Service→Port Priority to load the following page.
299
Figure 12-7 Port Priority Config
Configuration Procedure:
Select the desired port or LAG to set its priority. Click Apply.
Entry Description:
UNIT:1/LAGS: Click 1 to configure the physical ports. Click LAGS
to configure
the link aggregation groups.
Select:
Select the desired port to configure its priority. It is
multi-optional.
Port:
Displays the physical port number of the switch.
Priority: Specify the CoS queue that the port will be mapped to.
The packets are firstly mapped to CoS queues, then to TC
queues according to the 802.1P/CoS to Queue Mapping
relations.
LAG: Displays the aggregation group which the port is in.
Note:
1) All the ports in the same LAG should be assigned with the same port priority.
2) To complete QoS function configuration, you have to go to the Schedule Mode page to
select a schedule mode after the configuration is finished on this page.
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Configuration Procedure:
Step
Operation
Description
1 Enable the port Priority Required. On QoS→Class of Service→Trust Mode
page, select untrusted mode.
2 Select the port priority Required. On QoS→Class of Service→Port Priority
page, configure the port priority.
3 Configure the mapping
relation between the CoS
priority and TC
Required. On QoS→Class of Service→802.1P/CoS
to Queue Mapping
page, configure the mapping
relation between the CoS and TC.
4 Select a schedule mode Required. On QoS→Class of Service→Schedule
Mode page, select a schedule mode.
12.1.3 802.1P/CoS to Queue Mapping
On this page you can configure the mapping relation between the 802.1P priority CoS-id and the
TC-id.
802.1P gives the Pri field in 802.1Q tag a recommended definition. This field, ranging from 0-7, is
used to divide packets into 8 priorities. 802.1P Priority is enabled by default, so the packets with
802.1Q tag are mapped to different priority levels based on 802.1P priority mode but the
untagged packets are mapped based on port priority mode. With the same value, the 802.1P
priority tag and the CoS will be mapped to the same TC.
Choose the menu QoS→Class of Service→802.1P/CoS to Queue Mapping to load the
following page.
Figure 12-8 802.1P Priority
Configuration Procedure:
Configure the CoS-id-TC mapping relations. Click Apply.
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Entry Description:
CoS-id: CoS-
id is a value for the switch to establish mapping relations
between the priorities and TC queues. The valid values are from
0 to 7 and correspond to the 802.1P priority levels.
Queue TC-id: Select a TC queue that you want the CoS-id to be mapped to.
The switch supports 7
TC queues, from TC0 for the lowest
priority to TC 6 for the highest priority.
Note:
To complete QoS function configuration, you have to go to the Schedule Mode page to select
a schedule mode after the configuration is finished on this page.
Configuration Procedure:
Step
Operation
Description
1 Enable the 802.1P Priority Required. On QoS→Class of Service→Trust Mode
page, select trust 802.1p mode.
2 Configure the mapping
relation between the 802.1P
priority CoS and the TC
Required. On QoS→Class of Service→802.1P/CoS
to Queue Mapping
page, configure the mapping
relation between the 802.1P priority CoS and the TC.
3 Select a schedule mode Required. On QoS→Class of Service→Schedule
Mode page, select a schedule mode.
12.1.4 DSCP to Queue Mapping
On this page you can configure DSCP priority. DSCP (DiffServ Code Point) is a new definition to
IP ToS field given by IEEE. This field is used to divide IP datagram into 64 priorities. When trust
ip-dscp mode is selected, IP datagram are mapped to different priority levels based on DSCP
priority mode; non-IP datagram with 802.1Q tag are mapped to different priority levels based on
802.1P priority mode if trust 802.1p mode is selected; the untagged non-IP datagram are
mapped based on port priority mode.
302
Choose the menu QoS→Class of Service→DSCP to Queue Mapping to load the following
page.
Figure 12-9 DSCP Priority
Configuration Procedure:
Configure the DSCP-TC mapping relations. Click Apply.
Entry Description:
DSCP: Select the desired DSCP priority.
DSCP priority represents the DSCP field in the IP packet header.
It comprises 6 bits and the valid values are from 0 to 63.
Queue TC-id: Select a TC queue that the DSCP priority will be mapped to.
The switch supports 7 TC queues, from TC0 for the lowest
priority to TC 6 for the highest priority.
Note:
To complete QoS function configuration, you have to go to the Schedule Mode page to select
a schedule mode after the configuration is finished on this page.
Configuration Procedure:
Step
Operation
Description
1 Enable DSCP Priority Required. On QoS→Class of Service→Trust Mode
page, select trust ip-dscp mode.
2 Configure the mapping
relation between the DSCP
priority and TC
Required. On QoS→Class of Service→DSCP
Priority page, enable DSCP Priority and configure
the mapping relation between the DSCP priority and
TC.
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3 Select a schedule mode Required. On QoS→Class of Service→Schedule
Mode page, select a schedule mode.
12.1.5 Schedule Mode
On this page you can select a schedule mode for the switch. When the network is congested,
the problem that many packets compete for resources must be solved, usually in the way of
queue scheduling. The switch will control the forwarding sequence of the packets according to
the priority queues and scheduling algorithms you set. On this switch, the priority levels are
labeled as TC0, TC1…TC6.
Choose the menu QoS→Class of Service→Schedule Mode to load the following page.
Figure 12-10 Schedule Mode
Configuration Procedure:
1) Select a schedule mode. Click Apply.
2) (Optional) Configure the weight value of the each TC queue if the schedule mode is WRR of
SP+WRR. Click Apply.
Entry Description:
Schedule Mode Config
SP-Mode: Strict-
Priority Mode. In this mode, the queue with higher priority
will occupy the whole bandwidth. Packets in the queue with
lower priority are sent onl
y when the queue with higher priority is
empty.
WRR-Mode:
Weight Round Robin Mode. In this mode, packets in all the
queues are sent in order based on the weight value for each
queue. The weight value ratio of TC0, TC1, TC2 to TC6
is
1:2:3:4:5:6:7.
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SP+WRR-Mode: Strict-
Priority + Weight Round Robin Mode. In this mode, this
switch provides two scheduling groups, SP group and WRR
group. Queues in SP group and WRR group are scheduled
strictly based on strict-
priority mode while the queues inside
WRR group follow the WRR mode. In SP+WRR mode, TC6
is in
the SP group; TC0, TC1, TC2 to TC5
belong to the WRR group
and the weight value ratio of TC0, TC1, TC2 to TC5 is 1:2:3:4:5:6
.
In this way, when scheduling queues, the switch allows TC6
to
occupy the whole bandwid
th following the SP mode and the
TC0, TC1, TC2 to TC6 in the WRR group will take up the
bandwidth according to their ratio 1:2:3:4:5:6:7.
Queue Minimum Bandwidth
Queue Minimum
Bandwidth:
Set Minimum guaranteed bandwidth for TC0-
TC6. Valid
bandwidth range
is 0% to 100%. Total queue minimum
bandwidth value is 100%.
12.2 DiffServ
Differentiated Services (DiffServ) feature allows traffic to be classified into streams and given
certain QoS treatment in accordance with defined per-hop behaviors.
Packets are classified based on the criteria which is defined by a class. Policy attributes may be
defined on a per-class instance basis, and it is these attributes that are applied when a match
occurs. A policy can contain multiples classes. When the policy is active, the actions taken
depend on which class matches the packet. The policy can be added to the ports after service
configuration.
The DiffServ function can be implemented on Global, Class Summary, Class Config, Policy
Summary, Policy Config and Servive Config pages.
12.2.1 Global
On this page you can configure the DiffServ Admin Mode and view the DiffServ Entry Table.
305
Choose the menu QoS→DiffServ→Global to load the following page.
Figure 12-11 Global Config
Configuration Procedure:
Enable the DiffServ Admin Mode and click Apply.
Entry Description:
DiffServ Admin
Mode:
Enable or disable the administrative mode of DiffServ on the device.
While disabled, the DiffServ configuration is retained and can be
changed, but it is not
active. While enabled, Differentiated Services
are active.
Class Table:
The current and maximum number of classifier entries in the table.
DiffServ classifiers differentiate among traffic types.
Class Rule Table: The current and maximum number of class r
ule entries in the table.
Class rules specify the match criteria that belong to a class
definition.
Policy Table:
The current and maximum number of policy entries in the table. The
policy determines the traffic conditioning or service provisioning
actions applied to a traffic class.
Policy Instance
Table:
The current and maximum number of policy-class instance entries in
the table. A policy-
class instance is a policy that is associated with
an existing DiffServ class.
Policy Attribute
Table:
The current
and maximum number of policy attribute entries in the
table. A policy attribute entry attaches various policy attributes to a
policy-class instance.
Service Table:
The current and maximum number of service entries in the table. A
service entry associates
a DiffServ policy with an interface and
inbound or outbound direction.
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12.2.2 Class Summary
On this page you can configure DiffServ classes and view summary information about the
classes that exist on the device.
Choose the menu QoS→DiffServ→Class Summary to load the following page.
Figure 12-12 Class Summary
Configuration Procedure:
Specify the name, type and protocol of the DiffServ Class, then click Create.
Entry Description:
Name:
Enter the class name. It ranges from 1 to 31 characters.
Type:
The class type.
Protocol:
The Layer 3 protocol to use for filtering class types, which is
either IPv4 or IPv6.
Match Criteria:
Match criteria detail information of classes.
307
12.2.3 Class Config
Choose the menu QoS→DiffServ→Class Config to load the following page.
Figure 12-13 Class Config
Configuration Procedure:
Select a class from the drop-down list. Define the criteria to associate with a DiffServ class, then
click submit.
Entry Description:
Class:
The name of the class. To configure match criteria for a class,
select its name from the menu.
L3 Protocol:
The Layer 3 protocol to use for filtering class types, which is
either IPv4 or IPv6.
Any: Select this option
to specify that all packets are considered to
match the specified class. There is no need to configure
additional match criteria if Any is selected because a match will
occur on all packets.
308
Reference Class: Select this option to reference another class
for criteria. The
match criteria defined in the referenced class is as match
criteria in addition to the match criteria you define for the
selected class. After selecting this option, the classes that can
be referenced are displayed. Select the class to re
ference. A
class can reference at most one other class of the same type.
CoS:
Select this option to require the Class of Service (CoS) value in
an Ethernet frame header to match the specified CoS value.
Inner CoS: Select this option to require the second
ary CoS value in an
Ethernet frame header to match the specified secondary CoS
value.
EtherType:
Select this option to require the EtherType value in the Ethernet
frame header to match the specified EtherType value.
VLAN: Select this option to require a
packet's VLAN ID to match a
VLAN ID.
Inner VLAN:
Select this option to require a packet's VLAN ID to match a
secondary VLAN ID.
S-MAC:
Select this option to require a packet's source MAC address to
match the specified MAC address.
D-MAC: Select this opt
ion to require a packet's destination MAC address
to match the specified MAC address.
S-IP:
Select this option to require the source IP address in a packet
header to match the specified values.
D-IP: Select this option to require the destination IP addre
ss in a
packet header to match the specified values.
S-IPv6:
Select this option to require the source IPv6 address in a packet
header to match the specified values.
D-IPv6:
Select this option to require the destination IPv6 address in a
packet header to match the specified values.
S-Port:
Select this option to require a packet's TCP/UDP source port to
match the specified port number.
D-Port:
Select this option to require a packet's TCP/UDP destination
port to match the specified port number.
DSCP: Sele
ct this option to require the packet's IP DiffServ Code Point
(DSCP) value to match the specified value.
IP ToS:
Select this option to require the packet's Type of Service (ToS)
bits in the IP header to match the specified value.
IP Pre: Select this option to require the packet's IP Precedence value to
match the number configured in the IP Precedence Value field.
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IP Protocol:
Select this option to require a packet header's Layer 4 protocol
to match the specified value.
Flow Label: Select this option to
require an IPv6 packet's flow label to match
the configured value.
12.2.4 Policy Summary
Choose the menu QoS→DiffServ→Policy Summary to load the following page.
Figure 12-14 802.1P Priority
Configuration Procedure:
Create DiffServ policies and specify the traffic flow direction to which the policy is applied. Then
click Create.
Entry Description:
DiffServ Policy Create
Name:
Enter the DiffServ policy name. It ranges from 1 to 31
characters.
Type:
Specify the traffic flow direction to which the policy is applied.
DiffServ Policy Table
Name:
The name of the DiffServ policy.
Type:
The traffic flow direction to which the policy is applied.
Class Member:
The DiffServ class or classes that have been added to the
policy.
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12.2.5 Policy Config
Choose the menu QoS→DiffServ→Policy Config to load the following page.
Figure 12-15 DSCP Priority
Configuration Procedure:
Add or remove a DiffServ policy-class association and configure the policy attributes.
Entry Description:
DiffServ Policy Config
Policy: The name of the policy. To add a class to the policy, remove a
class from the policy, or configure the policy attributes, you
must first select its name from the menu.
Type:
The traffic flow direction to which the policy is applied.
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Class:
The DiffServ class or classes associated with the policy. The
policy is applied to a packet when a class match within that
policy-class is found.
Add:
Click this button to show the avaliable class list menu.
DiffServ Policy Attribute
Class:
Select a class to configure the policy attribute.
Assign Queue:
Select this option to assign matching packets to a traffic queue.
Use the Queue ID field to select the queue to which the packets
of this policy-class are assigned.
Drop:
Select this option to drop packets that match the policy-class.
Mark CoS:
Select this option to mark all packets in a traffic stream with the
specified Class of Service (CoS) queue value. Use the Class of
Service field to select the CoS value to mark in the priority
field
of the 802.1p header (the only tag in a single tagged packet or
the first or outer 802.1Q tag of a double VLAN tagged packet). If
the packet does not already contain this header, one is inserted.
Mark CoS as
Secondary CoS :
Select this option to ma
rk the priority field of the 802.1p header
in the outer tag of a double-
VLAN tagged packet with the same
CoS value that is included in the inner tag.
Mark DSCP:
Select this option to mark all packets in the associated traffic
stream with the specified IP DSCP value.
Mark Precedence:
Select this option to mark all packets in the associated traffic
stream with the specified IP Precedence value. After you select
this option, use the IP Precedence Value field to select the IP
Precedence to mark in packets that match the policy-class.
Mirror Interface:
Select this option to copy the traffic stream to a specified
egress port (physical or LAG) without bypassing normal packet
forwarding. This action can occur in addition to any marking or
policing action. It may
also be specified along with a QoS queue
assignment. Use the Interface menu to select the interface to
which traffic is mirrored.
Police Simple:
Select this option to enable the simple traffic policing style for
the policy-class. The simple form of the po
lice attribute uses a
single data rate and burst size, resulting in two outcomes
(conform and violate).
Police Single Rate: Select this option to enable the single-
rate traffic policing style
for the policy-class. The single-rate form of the police attrib
ute
uses a single data rate and two burst sizes, resulting in three
outcomes (conform, exceed, and violate).
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Police Two Rate: Select this option to enable the two-
rate traffic policing style for
the policy-class. The two-rate form of the police attribute
uses
two data rates and two burst sizes. Only the smaller of the two
data rates is intended to be guaranteed.
Redirect Interface:
Select this option to force a classified traffic stream to the
specified egress port (physical port or LAG). Use the Interfac
e
field to select the interface to which traffic is redirected.
Note:
To complete QoS function configuration, you have to go to the Schedule Mode page to select
a schedule mode after the configuration is finished on this page.
12.2.6 Service Config
Choose the menu QoS→DiffServ→Service Config to load the following page.
Figure 12-16 DSCP Priority
Configuration Procedure:
Add DiffServ policies to interfaces or remove policies from interfaces.
Entry Description:
DiffServ Service Config
Policy:
Select a policy.
Type:
Displays the traffic flow direction to which the policy is applied.
Interface:
Select one or more interfaces bound to the policy.
DiffServ Service Table
Interface:
Displays the interfaces that have an associated policy.
Type:
Displays the traffic flow direction to which the policy is applied.
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State:
The status of the policy on the interface. A policy is Up if
DiffServ is globally enabled, and if the interface is
administratively enabled and has a link. Otherwise, the status is
Down.
Policy:
The DiffServ policy associated with the interface.
12.3 Bandwidth Control
Bandwidth function, allowing you to control the traffic rate and broadcast flow on each port to
ensure network in working order, can be implemented on Rate Limit and Storm Control pages.
12.3.1 Rate Limit
Rate limit functions to control the egress traffic rate on each port via configuring the available
bandwidth of each port. In this way, the network bandwidth can be reasonably distributed and
utilized.
Choose the menu QoS→Bandwidth Control→Rate Limit to load the following page.
Figure 12-17 Rate Limit
Configuration Procedure:
1) Configure the upper rate limit for the port to send packets.
2) Click Apply.
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Entry Description:
UNIT:1/LAGS: Click 1 to configure the physical ports. Click LAGS
to configure
the link aggregation groups.
Select:
Select the desired port for Rate configuration. It is
multi-optional.
Port:
Displays the port number of the switch.
Egress Rate: Configure the bandwidth for sending packets on the port.
LAG:
Displays the LAG number which the port belongs to.
Note:
When egress rate limit feature is enabled for one or more ports, you are suggested to disable
the flow control on each port to ensure the switch works normally.
12.3.2 Storm Control
Storm Control function allows the switch to filter broadcast, multicast and UL frame in the
network. If the transmission rate of the three kind packets exceeds the set bandwidth, the
packets will be automatically discarded to avoid network broadcast storm.
Choose the menu QoS→Bandwidth Control→Storm Control to load the following page.
Figure 12-18 Storm Control
Configuration Procedure:
1) Select the port(s) and configure the upper rate limit for forwarding broadcast packets,
multicast packets and UL frames.
2) Click Apply.
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Entry Description:
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired port for Storm Control configuration. It is
multi-optional.
Port: Displays the port number of the switch.
Broadcast:
Input the bandwidth for receiving broadcast packets on the
port. The packet traffic exceeding the bandwidth will be
discarded. For gigabit ports, valid values are from 1 to 1488000
pps, and for ten-gigabit ports, valid values are from 1 to
14880000 pps.
Or you can s
elect Disable to disable the broadcast control
function for the port.
Multicast:
Input the bandwidth for receiving multicast packets on the
port. The packet traffic exceeding the bandwidth will be
discarded. For gigabit ports, valid values are from 1 to 1488000
pps, and for ten-gigabit ports, valid values are from 1 to
14880000 pps.
Or you can s
elect Disable to disable the multicast control
function for the port.
UL-Frame: Input the bandwidth for receiving UL-
Frame on the port. The
packet traffic exceeding the bandwidth will be discarded. For
gigabit ports, valid values are from 1 to 1488000
pps, and for
ten-gigabit ports, valid values are from 1 to 14880000 pps.
Or you can select Disable to disable the UL-
Frame control
function for the port.
LAG:
Displays the LAG number which the port belongs to.
12.4 Voice VLAN
Overview
The voice VLAN feature is used to prioritize the transmission of voice traffic. Voice traffic is
typically more time-sensitive than data traffic, and the voice quality can deteriorate a lot
because of packet loss and delay. To ensure the high voice quality, you can configure the voice
VLAN and set priority for voice traffic.
OUI Address (Organizationally Unique Identifier Address)
The OUI address is used by the switch to determine whether a packet is a voice packet. An OUI
address is the first 24 bits of a MAC address, and is assigned as a unique identifier by IEEE
(Institute of Electrical and Electronics Engineers) to a device vendor. If the source MAC address
of a packet complies with the OUI addresses in the switch, the switch identifies the packet as a
voice packet and prioritizes it in transmission.
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The Voice VLAN function can be implemented on Global Config, Port Config and OUI Config
pages.
12.4.1 Global Config
Choose the menu QoS→Voice VLAN→Global Config to load the following page.
Figure 12-19 Global Configuration
Configuration Procedure
：
1) Enable the voice VLAN feature, and enter a VLAN ID.
2) Specify a priority for the voice VLAN, and click Apply.
Note:
1. Before configuring the voice VLAN, you need to create a VLAN for voice traffic. For details
about VLAN Configuration, please refer to 802.1Q VLAN.
2. VLAN 1 is a default VLAN and cannot be configured as the voice VLAN.
3. Only one VLAN can be set as the voice VLAN on the switch.
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12.4.2 Port Config
Choose the menu QoS→Voice VLAN→Port Config to load the following page.
Figure 12-20 Port Config
Configuration Procedure:
1) Select your desired ports/LAGs and enable the Voice VLAN mode for selected ports.
2) Click Apply.
Entry Description:
Voice VLAN Mode:
Enable or disable the administrative mode of OUI-based Voice
VLAN on the interface.
Operational Status:
Displays the current state of the ports that are connected to
voice devices.
Up: The corresponding port is enabled with the voice VLAN
mode and has a link.
Down: The corresponding port is not enabled with the voice
VLAN mode or has no link.
12.4.3 OUI Config
If the OUI address of your voice device is not in the OUI table, you need to add the OUI address
to the table.
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Choose the menu QoS→Voice VLAN→OUI Config to load the following page.
Figure 12-21 OUI Config
Configuration Procedure:
1) Enter an OUI address and give a description about the OUI address.
2) Click Create to add an OUI address to the table.
Entry Description:
OUI:
Enter the OUI address of your device.
Description:
Give an OUI address description for identification. The length is
no more than 16 characters.
12.5 Auto VoIP
Overview
The Auto VoIP feature is used to prioritize the transmission of voice traffic. Voice over Internet
Protocol (VoIP) enables telephone calls over a data network, and the Auto VoIP feature helps
provide a classification mechanism for voice packets. When Auto VoIP is configured on a port
that receives both voice and data traffic, this feature can help ensure that the sound quality of
an IP phone does not deteriorate when data traffic on the port is heavy.
To apply the Auto VoIP configuration, you need to further configure LLDP and DiffServ. For
details, see
LLDP
and
DiffServ
.
12.5.1 Auto VoIP Config
Before configuring Auto VoIP, you need to create a VLAN for voice traffic. For details about
VLAN configuration, see
802.1Q VLAN
.
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Choose the menu QoS > Auto VoIP > Auto VoIP Config to load the following page.
Figure 12-22 Auto VoIP Config
Configuration Procedure:
1) Enable the Admin mode of Auto VoIP.
2) Select your desired ports and choose the interface mode and enter corresponding
interface value; choose the CoS override mode and click Apply.
3) Configure the corresponding module based on the interface mode.
Entry Description:
Admin Mode:
Enable or disable the Admin mode of Auto VoIP.
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired port for Auto VoIP configuration. It is
multi-optional.
Port:
Displays the port number of the switch.
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Interface Mode:
Indicates how an IP phone connected to the port should send
voice traffic
• VLAN ID – Forward voice traffic in the specified Auto VoIP
VLAN. If you choose VLAN ID, you need to configure LLDP-MED
to instruct voice devices to send tagged voice traffic, and
create a priority policy in DiffServ for voice traffic. For details,
see
LLDP
and
DiffServ.
• Dot1p – Tag voice traffic with the specified 802.1p priority
value. If you choose Dot1p, you need to configure LLDP-MED to
instruct voice devices to send tagged voice traffic, and set
802.1P Priority in Class of Service. For details, see
LLDP
and
Class of Service
.
• None – The IP phone sends voice traffic based on the
configuration of itself.
• Untagged – Instruct the IP phone to send untagged voice
traffic.
• Disable – Disable the Auto VoIP feature on the interface.
Interface Value:
If you have selected VLAN ID or Dot1p as the Auto VoIP
Interface Mode, specify the corresponding voice VLAN ID or the
Dot1p priority value that the connected IP phone should use for
voice traffic.
CoS Override
Mode
Enable or disable the Class of Service override mode
• Enabled – The port ignores the 802.1p priority value in the
Ethernet frames it receives from connected devices.
• Disabled – The port trusts the priority value in the received
frame.
O
perating Status
Displays operating status of the voice VLAN feature on the
interface. To make it enabled, you must enable the voice VLAN
both globally and on the interface. Additionally, the interface
must be up and have a link.
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321
Chapter 13 ACL
The fast growth of network size and traffic brings challenges to network security and
bandwidth allocation. Packet filtering can prevent unauthorized access behaviors and improve
bandwidth use.
ACL (Access Control List), which is based on rule matching, is primarily used for packet filtering.
ACL accurately identifies and controls packets on the network to manage network access
behaviors, prevent network attacks, and improve bandwidth use efficiency. In this way, ACL
ensures security and high service quality on networks. It is usually applied in the following
occasions:
To prevent various network attacks, such as IP (Internet Protocol), TCP (Transmission Control
Protocol), and ICMP (Internet Control Message Protocol) packets attacks.
To manage network access behaviors, such as controlling access to a network or to specific
resources on your network.
The ACL module is mainly for ACL configuration of the switch, including three submenus:
Time-Range, ACL Config and ACL Binding.
13.1 Time-Range
If a configured ACL is needed to be effective in a specified time-range, a time-range should be
firstly specified in the ACL. As the time-range based ACL takes effect only within the specified
time-range, data packets can be filtered by differentiating the time-ranges.
On this switch absolute time and periodic time can be configured. Configure an absolute time
section in the form of “the start date to the end date” to make ACLs effective; configure a
periodic time section to make ACLs effective on the fixed days of the week.
The Time-Range configuration can be implemented on Time-Range Summary page.
13.1.1 Time-Range Summary
On this page you can view the current time-ranges.
Choose the menu ACL → Time-Range → Time-Range Summary to load the following page.
Figure 13-1 Time-Range Table
Configuration Procedure:
1) To add a new time range, click “Add” to load the following page. Then enter the name of
the time-range for time identification and click “Create”. You can view the entry in the
Time-Range Table.
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2) To edit the time range, click “Edit” in the Time-Range Table to load the following page. Then
configure Absolute entry or Periodic entry according to your actual needs.
Entry Description:
Select:
Select the desired entry to delete the corresponding time-range.
Time-Range Name:
Displays the name of the time-range.
Time-Range Status: Shows whether the time range is Activ
e or Inactive. A time range is
i
nactive if the current day and time do not fall within any time range
entries configured for the time range.
Absolute Entry: Shows whether an absolute time en
try is currently configured for the
time range.
Periodic Entry
Count:
The number of periodic time range entries currently configured for
the time range.
Operation:
Display and edit the information of this time-range.
Name:
The name of the time-range.
Absolute: Select Absolute to configure absolute time-range.
The ACL rule
based on this time-
range takes effect only when the system time is
within the absolute time-range.
Start Date:
Configure values for the Start Date and the Time of Day.
End Date:
Configure values for the End Date and the Time of Day.
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Week: Select Week to configure week time-
range. The ACL rule based on
this time-
range takes effect only when the system time is within the
week time-range.
Start Time:
Configure values for the Start Time of Day.
End Time:
Configure values for the End Time of Day.
Entry Type:
The type of time range entry.
Starts:
For an Absolute entry, indicates the time, day, month, and year that
the entry begins. For a Periodic entry, indicates the time that the
entry begins.
Ends:
For an Absolute entry, indicates the time, day, month, and year that
the entry ends. For a Periodic entry, indicates the time that the entry
ends.
Week-data:
For a Periodic entry, indicates the day(s) of the week of the entry.
Delete:
Click the Delete button to delete the corresponding time-slice.
13.2 ACL Config
An ACL may contain a number of rules, and each rule specifies a different package range.
Packets are matched in match order. Once a rule is matched, the switch processes the
matched packets taking the operation specified in the rule without considering the other rules,
which can enhance the performance of the switch.
Packets are classified based on match rules in order of the rules. For different types of ACL,
you can define the rules based on source or destination IP address, source or destination MAC
address, protocol type, port number and so on.
There are three types of ACL including MAC ACL, Standard-IP ACL and Extend-IP ACL.
13.2.1 ACL Summary
On this page, you can view the all the ACLs and their rules configured in the switch. The rules in
an ACL are listed in an ascending order of configuration time, no matter what their rule IDs are.
By default, a rule configured earlier is listed before a rule configured later. The switch matches
a received packet with the rules in order. When a packet matches a rule, the device stops the
match process and performs the action defined in the rule.
In ACL rule table, you can view all the ACLs and their rules. You can also delete an ACL or an
ACL rule, or change the matching order if needed.
Choose the menu ACL → ACL Config → ACL Summary to load the following page.
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Figure 13-2 ACL Summary
Configuration Procedure:
Select an ACL ID from the drop-down list. You can view corresponding rules in the Rule Table.
13.2.2 ACL Create
On this page you can create ACLs.
Choose the menu ACL → ACL Config → ACL Create to load the following page.
Figure 13-3 ACL Create
Configuration Procedure:
Enter an ID number in the ACL ID field, then click Apply.
Entry Description:
ACL ID:
Enter a number that is used to identify the ACL.
Rule Order:
User Config order is set to be match order in this ACL.
13.2.3 MAC ACL
MAC ACLs analyze and process packets based on a series of match conditions, which can be
the source MAC addresses, destination MAC addresses and EtherType carried in the packets.
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Choose the menu ACL → ACL Config → MAC ACL to load the following page.
Figure 13-4 Create MAC Rule
Configuration Procedure:
1) Select an ACL ID from the drop-down list, enter a Rule ID, then specify the operation of the
rule.
2) Select and define the rule's packet-matching criteria.
Entry Description:
ACL ID:
Select the desired MAC ACL for configuration.
Rule ID:
Enter the rule ID.
Operation:
Select the operation for the switch to process packets which match
the rules.
Permit: Forward packets.
Deny: Discard Packets.
S-MAC:
Enter the source MAC address contained in the rule.
D-MAC:
Enter the destination MAC address contained in the rule.
MASK:
Enter MAC address mask. If it is set to 1, it must strictly match the
address.
VLAN ID:
Enter the VLAN ID contained in the rule.
EtherType:
Enter EtherType contained in the rule.
User Priority:
Select the user priority contained in the rule for the tagged packets
to match.
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Time-Range:
Select the time-range for the rule to take effect.
S-Condition:
Select S-Condition to limit the transmission rate of the data packets.
Rate:
The transmission rate of the data packets. Valid values are (1 to
1000000) in Kbps.
Qos Remark:
Select QoS Remark to forward the data packets based on the QoS
settings.
S-Mirror:
Select S-Mirror to mirror the data packets to the specific port.
Redirect:
Select Redirect to change the forwarding direction of the data
packets.
Port:
Redirect or mirror the data packets to the specific port.
13.2.4 Standard-IP ACL
Standard-IP ACLs analyze and process data packets based on a series of match conditions,
which can be the source IP addresses and destination IP addresses carried in the packets.
Choose the menu ACL → ACL Config → Standard-IP ACL to load the following page.
Figure 13-5 Create Standard-IP Rule
Configuration Procedure
1) Select an ACL ID from the drop-down list, enter a Rule ID, then specify the operation of the
rule.
2) Select and define the rule's packet-matching criteria.
Entry Description
ACL ID:
Select a Standard-IP ACL from the drop-down list.
Rule ID:
Enter an ID number that is used to identify the rule. It cannot be the
same as the existing Standard-IP Rule IDs.
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Operation:
Select the operation for the switch to process packets which match
the rules.
Permit: Forward packets.
Deny: Discard Packets.
S-IP:
Enter the source IP address contained in the rule.
Mask: Enter IP address mask. If it is set to 1,
it must strictly match the
address.
Time-Range:
Select the time-range for the rule to take effect.
S-Condition:
Select S-Condition to limit the transmission rate of the data packets.
Rate: The transmission rate of the data packets. Valid values are (1
to
1000000) in Kbps.
Qos Remark:
Select QoS Remark to forward the data packets based on the QoS
settings.
S-Mirror:
Select S-Mirror to mirror the data packets to the specific port.
Redirect: Select Redirect to change the forwarding direction of the data
packets.
Port:
Redirect or mirror the data packets to the specific port.
13.2.5 Extend-IP ACL
Extend-IP ACLs analyze and process data packets based on a series of match conditions,
which can be the source IP addresses, destination IP addresses, IP protocol and other
information of this sort carried in the packets.
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Choose the menu ACL → ACL Config → Extend-IP ACL to load the following page.
Figure 13-6 Create Extend-IP Rule
Configuration Procedure
1) Select an ACL ID from the drop-down list, enter a Rule ID, then specify the operation of the
rule.
2) Select and define the rule's packet-matching criteria.
Entry Description
ACL ID:
Select a Standard-IP ACL from the drop-down list.
Rule ID:
Enter an ID number that is used to identify the rule. It cannot be the
same as the existing Standard-IP Rule IDs.
Operation:
Select the operation for the switch to process packets which match
the rules.
Permit: Forward packets.
Deny: Discard Packets.
S-IP:
Enter the source IP address contained in the rule.
D-IP:
Enter the destination IP address contained in the rule.
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Mask:
Enter IP address mask. If it is set to 1, it must strictly match the
address.
Select ICMP:
Configure the predefined ICMP type and code.
ICMP Type:
Configure the predefined ICMP type.
ICMP Code:
Configure the predefined ICMP code.
IP Protocol:
Select IP protocol contained in the rule.
TCP Flag
：
Configure TCP flag when TCP is selected from the pull-
down list of IP
Protocol.
S-Port: Configure TCP/IP source port contained in the rule when TCP/UDP is
selected from the pull-down list of IP Protocol.
D-Port: Configure TCP/IP destination por
t contained in the rule when
TCP/UDP is selected from the drop-down list of IP Protocol.
DSCP:
Enter the DSCP information contained in the rule.
IP ToS:
Enter the IP ToS contained in the rule.
IP Pre:
Enter the IP Precedence contained in the rule.
Time-Range:
Select the time-range for the rule to take effect.
S-Condition:
Select S-Condition to limit the transmission rate of the data packets.
Rate:
The transmission rate of the data packets. Valid values are (1 to
1000000) in Kbps.
Qos Remark: Select
QoS Remark to forward the data packets based on the QoS
settings.
S-Mirror:
Select S-Mirror to mirror the data packets to the specific port.
Redirect:
Select Redirect to change the forwarding direction of the data
packets.
Port:
Redirect or mirror the data packets to the specific port.
13.3 ACL Binding
ACL Binding function can have the policy take its effect on a specific port/VLAN. The ACL will
take effect only when it is bound to a port/VLAN. In the same way, the port/VLAN will receive
the data packets and process them based on the ACL only when the ACL is bound to the
port/VLAN.
The ACL Binding can be implemented on Binding Table, Port Binding and VLAN Binding
pages.
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13.3.1 Binding Table
On this page view the policy bound to port/VLAN.
Choose the menu ACL → ACL Binding → Binding Table to load the following page.
Figure13-7 Binding Table
Configuration Procedure
1) In the ACL VLAN-Bind Table, you can view VLAN binding entries.
2) In the ACL Port-Bind Table, you can view port binding entries.
3) You can also delete existing entries if needed.
Entry Description
Search Options
Show Mode:
Select a show mode appropriate to your needs.
ACL Vlan-Bind Table
Select:
Select the desired entry to delete the corresponding binding
ACL.
Index:
Displays the index of the binding ACL.
ACL ID:
Displays the ID or name of the binding ACL.
Interface:
Displays the VLAN ID bound to the ACL.
Direction:
Displays the binding direction.
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ACL Port-Bind Table
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired entry to delete the corresponding binding
ACL.
Index:
Displays the index of the binding ACL.
ACL ID:
Displays the ID or name of the binding ACL.
Interface:
Displays the port number bound to the ACL.
Direction:
Displays the binding direction.
13.3.2 Port Binding
On this page you can bind an ACL to a port.
Choose the menu ACL → ACL Binding → Port Binding to load the following page.
Figure13-8 Bind the ACL to the port
Configuration Procedure:
Select the ACL and port(s) you want to bind. Then click Apply.
Entry Description:
Port-Bind Config
ACL ID:
Select the ID or the name of the ACL you want to bind.
Port:
Select the port you want to bind.
Port-Bind Table
Index:
Displays the index of the binding ACL.
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ACL ID:
Displays the ID or name of the binding ACL.
Port: Displays the numb
er of the port bound to the corresponding
ACL.
Direction:
Displays the binding direction.
13.3.3 VLAN Binding
On this page you can bind an ACL to a VLAN.
Choose the menu ACL → ACL Binding → VLAN Binding to load the following page.
Figure13-9 Bind the ACL to the VLAN
Configuration Procedure:
Select the ACL and enter the VLAN ID. Then click Apply.
Entry Description:
VLAN-Bind Config
ACL ID:
Select the ID or name of the ACL you want to bind.
VLAN ID:
Enter the ID of the VLAN you want to bind.
VLAN-Bind Table
Index:
Displays the index of the binding ACL.
ACL ID:
Displays the ID or name of the binding ACL.
VLAN ID:
Displays the ID of the VLAN bound to the corresponding ACL.
Direction:
Displays the binding direction.
ACL Configuration Procedure:
Step
Operation
Description
1
Configure effective
time-range
Optional. On ACL → Time-Range →Time-Range
Summary configuration page, configure the effective
time-ranges for ACLs.
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Step
Operation
Description
2
Configure ACL rules Required. On ACL → ACL Config configuration pages,
configure ACL rules to match packets.
3
Bind the ACL to the
port/VLAN
Required. On ACL → ACL Binding configuration pages,
bind the ACL to the port/VLAN to make the ACL effective
on the corresponding port/VLAN.
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Chapter 14 Network Security
Network Security module is to provide the multiple protection measures for the network
security, including five submenus: IP-MAC Binding, DHCP Snooping, ARP Inspection, IP
Source Guard, DoS Defend and 802.1X. Please configure the functions appropriate to your
need.
14.1 IP-MAC Binding
The IP-MAC Binding function allows you to bind the IP address, MAC address, VLAN ID and the
connected Port number of the Host together. Basing on the IP-MAC binding table, ARP
Inspection and IP Source Guard functions can control the network access and only allow the
Hosts matching the bound entries to access the network.
The following two IP-MAC Binding methods are supported by the switch.
1. Manually: You can manually bind the IP address, MAC address, VLAN ID and the Port
number together in the condition that you have got the related information of the Hosts in
the LAN.
2. DHCP Snooping: You can use DHCP Snooping functions to monitor the process of the
Host obtaining the IP address from DHCP server, and record the IP address, MAC
address, VLAN and the connected Port number of the Host for automatic binding.
The two methods are also considered as the sources of the IP-MAC Binding entries. The
entries from different sources should be different from the other to avoid collision. Only the
entry from the source with the higher priority will take effect. The priority of Manual is higher
than that of Snooping.
The IP-MAC Binding function is implemented on the Binding Table and Manual Binding pages.
14.1.1 Binding Table
On this page, you can view the information of the bound entries.
Choose the menu Network Security→IP-MAC Binding→Binding Table to load the following
page.
Figure 14-1 Binding Table
Configuration Procedure:
Select a source type and click Search to search the specified type of entry.
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Entry Description:
Source:
Displays the Source of the entry.
• All: All the bound entries will be displayed.
• Manual:
Only the manually added entries will be
displayed.
• Snooping: Only the entries formed via DHCP Snooping
will be displayed.
IP
Click the Select button to quick-select the corresponding
entry based on the IP address you entered.
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired entry
to modify the Host Name and
Protect Type. It is multi-optional.
IP Address
Displays the IP Address of the Host.
MAC Address
Displays the MAC Address of the Host.
VLAN ID:
Displays the VLAN ID here.
Port:
Displays the number of port connected to the Host.
Source:
Displays the Source of the entry.
Protect
Type: Displays the
protect type of the entry. There are four protect
types:
• None: The entry does not apply to any feature.
• ARP Inspection:
The entry applies to the ARP
inspection feature.
• IP Source Guard:
The entry applies to the IP source
guard feature.
• All: The entry applies to both the
ARP inspection
feature and the IP source guard feature.
14.1.2 Manual Binding
You can manually bind the IP address, MAC address, VLAN ID and the Port number together in
the condition that you have got the related information of the Hosts in the LAN.
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Choose the menu Network Security→IP-MAC Binding→Manual Binding to load the following
page.
Figure 14-2 Manual Binding
Configuration Procedure:
Specify the IP address, MAC address, VLAN ID and port number, and click Bind.
Entry Description:
IP Address:
Enter the IP Address of the Host.
MAC Address:
Enter the MAC Address of the Host.
VLAN ID:
Enter the VLAN ID.
Port:
Select the number of port connected to the Host.
UNIT:
Select the unit ID of the desired member in the stack.
14.2 DHCP Snooping
Nowadays, the network is getting larger and more complicated. The amount of the PCs always
exceeds that of the assigned IP addresses. The wireless network and the laptops are widely
used and the locations of the PCs are always changed. Therefore, the corresponding IP
address of the PC should be updated with a few configurations. DHCP (Dynamic Host
Configuration Protocol, the network configuration protocol optimized and developed basing on
the BOOTP, functions to solve the above mentioned problems.
DHCP Working Principle
DHCP works via the “Client/Server” communication mode. The Client applies to the Server for
configuration. The Server assigns the configuration information, such as the IP address, to the
Client, so as to reach a dynamic employ of the network source. A Server can assign the IP
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address for several Clients, which is illustrated in the following figure. For details about the
DHCP Server function, please refer to 10.4 DHCP Server.
Figure 14-3 Network diagram for DHCP-snooping implementation
For different DHCP Clients, DHCP Server provides three IP address assigning methods:
1. Manually assign the IP address: Allows the administrator to bind the static IP address to
the specific Client (e.g.: WWW Server) via the DHCP Server.
2. Automatically assign the IP address: DHCP Server assigns the IP address without an
expiration time limitation to the Clients.
3. Dynamically assign the IP address: DHCP Server assigns the IP address with an
expiration time. When the time for the IP address expired, the Client should apply for a
new one.
The most Clients obtain the IP addresses dynamically, which is illustrated in the following
figure.
Figure 14-4 Interaction between a DHCP client and a DHCP server
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1. DHCP-DISCOVER Stage: The Client broadcasts the DHCP-DISCOVER packet to find
the DHCP Server.
2. DHCP-OFFER Stage: Upon receiving the DHCP-DISCOVER packet, the DHCP Server
selects an IP address from the IP pool according to the assigning priority of the IP
addresses and replies to the Client with DHCP-OFFER packet carrying the IP address
and other information.
3. DHCP-REQUEST Stage: In the situation that there are several DHCP Servers sending
the DHCP-OFFER packets, the Client will only respond to the first received
DHCP-OFFER packet and broadcast the DHCP-REQUEST packet which includes the
assigned IP address of the DHCP-OFFER packet.
4. DHCP-ACK Stage: Since the DHCP-REQUEST packet is broadcasted, all DHCP Servers
on the network segment can receive it. However, only the requested Server processes
the request. If the DHCP Server acknowledges assigning this IP address to the Client, it
will send the DHCP-ACK packet back to the Client. Otherwise, the Server will send the
DHCP-NAK packet to refuse assigning this IP address to the Client.
Option 82
The DHCP packets are classified into 8 types with the same format basing on the format of
BOOTP packet. The difference between DHCP packet and BOOTP packet is the Option field.
The Option field of the DHCP packet is used to expand the function, for example, the DHCP can
transmit the control information and network parameters via the Option field, so as to assign
the IP address to the Client dynamically. For the details of the DHCP Option, please refer to RFC
2132.
Option 82 records the location of the DHCP Client. Upon receiving the DHCP-REQUEST packet,
the switch adds the Option 82 to the packet and then transmits the packet to DHCP Server.
Administrator can be acquainted with the location of the DHCP Client via Option 82 so as to
locate the DHCP Client for fulfilling the security control and account management of Client. The
Server supported Option 82 also can set the distribution policy of IP addresses and the other
parameters according to the Option 82, providing more flexible address distribution way.
Option 82 can contain 255 sub-options at most. If Option 82 is defined, at least a sub-option
should be defined. This switch supports two sub-options: Circuit ID and Remote ID. Since there
is no universal standard about the content of Option 82, different manufacturers define the
sub-options of Option 82 to their need. For this switch, the sub-options are defined as the
following: The Circuit ID is defined to be the number of the port which receives the DHCP
Request packets and its VLAN number. The Remote ID is defined to be the MAC address of
DHCP Snooping device which receives the DHCP Request packets from DHCP Clients.
DHCP Cheating Attack
During the working process of DHCP, generally there is no authentication mechanism between
Server and Client. If there are several DHCP servers in the network, network confusion and
security problem will happen. The common cases incurring the illegal DHCP servers are the
following two:
1. It’s common that the illegal DHCP server is manually configured by the user by mistake.
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2. Hacker exhausted the IP addresses of the normal DHCP server and then pretended to
be a legal DHCP server to assign the IP addresses and the other parameters to Clients.
For example, hacker used the pretended DHCP server to assign a modified DNS server
address to users so as to induce the users to the evil financial website or electronic
trading website and cheat the users of their accounts and passwords. The following
figure illustrates the DHCP Cheating Attack implementation procedure.
Figure 14-5 DHCP Cheating Attack Implementation Procedure
DHCP Snooping feature only allows the port connected to the DHCP Server as the trusted port
to forward all types of DHCP packets and thereby ensures that users get proper IP addresses.
DHCP Snooping is to monitor the process of the Host obtaining the IP address from DHCP
server, and record the IP address, MAC address, VLAN and the connected Port number of the
Host for automatic binding. The bound entry can cooperate with the ARP Inspection, IP Source
Guard and the other security protection features. DHCP Snooping feature prevents the
network from the DHCP Server Cheating Attack by discarding the DHCP response packets on
the distrusted port, so as to enhance the network security.
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14.2.1 Global Config
Choose the menu Network Security→DHCP Snooping→Global Config to load the following
page.
Figure 14-6 DHCP Snooping
Note:
If you want to enable the DHCP Snooping feature for the member port of LAG, please ensure
the parameters of all the member ports are the same.
Configuration Procedure:
1) Enable DHCP Snooping globally and for the specified VLAN.
2) Configure Option 82.
3) Click Apply.
Entry Description:
DHCP Snooping:
Enable/Disable the DHCP Snooping function globally.
MAC Verify:
Enable or d
isable the MAC Verify feature. There are two fields
in the DHCP packet that contain the MAC address of the host.
The MAC Verify feature compares the two fields of a DHCP
packet and discards the packet if the two fields are different.
This prevents the IP a
ddress resource on the DHCP server
from being exhausted by forged MAC addresses.
VLAN ID:
Specify the VLAN ID in the format shown on the page.
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VLAN Configuration
Display:
Displays the VLANs that have been enabled with DHCP
Snooping.
Option 82 Config
Option 82 Support:
Enable/Disable the Option 82 feature.
Existed Option 82 field:
Select the operation for the Option 82 field of the DHCP
request packets from the Host.
•
Keep:
Indicates to keep the Option 82 field of the
packets.
•
Replace: Indicates to replac
e the Option 82 field of the
packets with the switch defined one.
•
Drop:
Indicates to discard the packets including the
Option 82 field.
Customization:
Enable or Disable the switch to define the Option 82.
Remote ID:
Enter the sub-option Remote ID for the customized Option 82.
14.2.2 Port Config
Choose the menu Network Security→DHCP Snooping→Port Config to load the following
page.
Figure 14-7 DHCP Snooping
Configuration Procedure:
Select one or more ports and configure the relevant parameters. Click Apply.
Entry Description:
Select:
Select your desired port for configuration. It is multi-optional.
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Port:
Displays the port number.
Trusted Port:
Select Enable/Disable the port to be a Trusted Port. Only the
Trusted Port can receive the DHCP packets from DHCP
servers.
Rate Limit:
Se
lect the value to specify the maximum amount of DHCP
messages that can be forwarded by the switch of this port
per second. The excessive DHCP packets will be discarded.
Circuit ID Customization:
Enable or Disable the switch to define Circuit ID.
Circuit ID:
Enter the sub-option Circuit ID for the customized Option 82.
LAG:
Displays the LAG to which the port belongs to.
14.3 ARP Inspection
Since ARP protocol is implemented with the premise that all the Hosts and Gateways are
trusted, there are high security risks during ARP Implementation Procedure in the actual
complex network. Thus, the cheating attacks against ARP, such as imitating Gateway, cheating
Gateway, cheating terminal Hosts and ARP Flooding Attack, frequently occur to the network,
especially to the large network such as campus network and so on. The following part will
simply introduce these ARP attacks.
Imitating Gateway
The attacker sends the MAC address of a forged Gateway to Host, and then the Host will
automatically update the ARP table after receiving the ARP response packets, which causes
that the Host cannot access the network normally. The ARP Attack implemented by imitating
Gateway is illustrated in the following figure.
Figure 14-8 ARP Attack - Imitating Gateway
As the above figure shown, the attacker sends the fake ARP packets with a forged Gateway
address to the normal Host, and then the Host will automatically update the ARP table after
receiving the ARP packets. When the Host tries to communicate with Gateway, the Host will
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encapsulate this false destination MAC address for packets, which results in a breakdown of
the normal communication.
Cheating Gateway
The attacker sends the wrong IP address-to-MAC address mapping entries of Hosts to the
Gateway, which causes that the Gateway cannot communicate with the legal terminal Hosts
normally. The ARP Attack implemented by cheating Gateway is illustrated in the following
figure.
Figure 14-9 ARP Attack – Cheating Gateway
As the above figure shown, the attacker sends the fake ARP packets of Host A to the Gateway,
and then the Gateway will automatically update its ARP table after receiving the ARP packets.
When the Gateway tries to communicate with Host A in LAN, it will encapsulate this false
destination MAC address for packets, which results in a breakdown of the normal
communication.
Cheating Terminal Hosts
The attacker sends the false IP address-to-MAC address mapping entries of terminal
Host/Server to another terminal Host, which causes that the two terminal Hosts in the same
network segment cannot communicate with each other normally. The ARP Attack implemented
by cheating terminal Hosts is illustrated in the following figure.
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Figure 14-10 ARP Attack – Cheating Terminal Hosts
As the above figure shown, the attacker sends the fake ARP packets of Host A to Host B, and
then Host B will automatically update its ARP table after receiving the ARP packets. When Host
B tries to communicate with Host A, it will encapsulate this false destination MAC address for
packets, which results in a breakdown of the normal communication.
Man-In-The-Middle Attack
The attacker continuously sends the false ARP packets to the Hosts in LAN so as to make the
Hosts maintain the wrong ARP table. When the Hosts in LAN communicate with one another,
they will send the packets to the attacker according to the wrong ARP table. Thus, the attacker
can get and process the packets before forwarding them. During the procedure, the
communication packets information between the two Hosts are stolen in the case that the
Hosts were unaware of the attack. That is called Man-In-The-Middle Attack. The
Man-In-The-Middle Attack is illustrated in the following figure.
Figure 14-11 Man-In-The-Middle Attack
Suppose there are three Hosts in LAN connected with one another through a switch.
Host A: IP address is 192.168.0.101; MAC address is 00-00-00-11-11-11.
Host B: IP address is 192.168.0.102; MAC address is 00-00-00-22-22-22.
Attacker: IP address is 192.168.0.103; MAC address is 00-00-00-33-33-33.
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1. First, the attacker sends the false ARP response packets.
2. Upon receiving the ARP response packets, Host A and Host B updates the ARP table of
their own.
3. When Host A communicates with Host B, it will send the packets to the false destination
MAC address, i.e. to the attacker, according to the updated ARP table.
4. After receiving the communication packets between Host A and Host B, the attacker
processes and forwards the packets to the correct destination MAC address, which makes
Host A and Host B keep a normal-appearing communication.
5. The attacker continuously sends the false ARP packets to the Host A and Host B so as to
make the Hosts always maintain the wrong ARP table.
In the view of Host A and Host B, their packets are directly sent to each other. But in fact, there
is a Man-In-The-Middle stolen the packets information during the communication procedure.
This kind of ARP attack is called Man-In-The-Middle attack.
ARP Flooding Attack
The attacker broadcasts a mass of various fake ARP packets in a network segment to occupy
the network bandwidth viciously, which results in a dramatic slowdown of network speed.
Meantime, the Gateway learns the false IP address-to-MAC address mapping entries from
these ARP packets and updates its ARP table. As a result, the ARP table is fully occupied by the
false entries and unable to learn the ARP entries of legal Hosts, which causes that the legal
Hosts cannot access the external network.
The IP-MAC Binding function allows the switch to bind the IP address, MAC address, VLAN ID
and the connected Port number of the Host together when the Host connects to the switch.
Basing on the predefined IP-MAC Binding entries, the ARP Inspection functions to detect the
ARP packets and filter the illegal ARP packet so as to prevent the network from ARP attacks.
The ARP Inspection function is implemented on the ARP Detect, ARP Defend and ARP
Statistics pages.
14.3.1 ARP Detect
ARP Detect feature enables the switch to detect the ARP packets basing on the bound entries
in the IP-MAC Binding Table and filter the illegal ARP packets, so as to prevent the network
from ARP attacks, such as the Network Gateway Spoofing and Man-In-The-Middle Attack, etc.
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Choose the menu Network Security→ARP Inspection→ARP Detect to load the following page.
Figure 14-12 ARP Detect
Configuration Procedure:
1) In the Global Configuration section, enable or disable the following features.
2) In the Enable VLAN section, enable ARP Detect for the VLAN.
Entry Description:
Validate Source MAC:
Enable or d
isable the switch to check whether the source
MAC address and the Sender MAC address are the same
when receiving an ARP packet. If not, the ARP packet will be
discarded.
Validate Destination
MAC:
Enable or disable the switch to check whether the
Destinati
on MAC address and the Target MAC address are
the same when receiving an ARP Reply packet. If not, the ARP
packet will be discarded.
Validate IP:
Enable or disable the switch to check whether the Sender IP
address of all ARP packets and the Target IP addr
ess of ARP
Reply packets are legal. The illegal packets will be discarded.
VLAN ID
Enable/Disable the ARP Detect function, and click the Apply
button to apply.
Logging:
With this option enabled, a log will be generated when an ARP
packet is discarded.
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14.3.2 ARP Defend
With the ARP Defend enabled, the switch can terminate receiving the ARP packets for 300
seconds when the transmission speed of the legal ARP packet on the port exceeds the defined
value so as to avoid ARP Attack flood.
Choose the menu Network Security→ARP Inspection→ARP Defend to load the following
page.
Figure 14-13 ARP Defend
Configuration Procedure:
Select one or more ports, and configure the relevant parameters. Then click Apply.
Entry Description:
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select your desired port for configuration. It is multi-optional.
Port:
Displays the port number.
Trust State:
Enable or disable this port to be a trusted port, on which the
ARP packets will be forwarded directly without checked.
Speed(10
-300)pps:
Enter a value to specify the maximum amount of the received
ARP packets per second.
Burst Interval(1
-15)s:
Enter a value to specify a time range. If the average speed of
received ARP packets
in this time range reach the limit, the port
will be shut down.
Status
Displays the status of the ARP attack.
Operation:
Click the Recover
button to restore the port to the normal
status. The ARP Defend for this port will be re-enabled.
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LAG:
Displays the LAG to which the port belongs to.
Note:
It’s not recommended to enable the ARP Defend feature for the LAG member port.
14.3.3 ARP Statistics
ARP Statistics feature displays the number of the illegal ARP packets received on each port,
which facilitates you to locate the network malfunction and take the related protection
measures.
Choose the menu Network Security→ARP Inspection→ARP Statistics to load the following
page.
Figure 14-14 ARP Statistics
Configuration Procedure:
1) In the Auto Refresh section, configure the Auto Refresh feature.
2) In the Illegal ARP Packet section, view the statistics of ARP packets in each VLAN.
Entry Description:
Auto Refresh:
Enable or disable the Auto Refresh feature.
Refresh Interval:
Specify the refresh interval to display the ARP Statistics.
VLAN ID:
Displays the VLAN ID.
Forwarded:
Displays the number of forwarded packets in this VLAN.
Dropped:
Displays the number of dropped packets in this VLAN.
14.4 IP Source Guard
IP Source Guard is to filter the IP packets based on the IP-MAC Binding entries. Only the
packets matched to the IP-MAC Binding rules can be processed, which can enhance the
bandwidth utility.
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Choose the menu Network Security→IP Source Guard to load the following page.
Figure 14-15 IP Source Guard
Configuration Procedure:
Select one or more ports, configure security type, and click Apply.
Entry Description:
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select your desired port for configuration. It is multi-optional.
Port:
Displays the port number.
Security Type:
Select Security Type for the port.
• Disable:
Select this option to disable the IP Source Guard
feature for the port.
• SIP: Only the packet
s with its source IP address and port
number matched to the IP-
MAC binding rules can be
processed.
• SIP+MAC:
Only the packets with its source IP address,
source MAC address and port number matched to the
IP-MAC binding rules can be processed.
LAG:
Displays the LAG to which the port belongs to.
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14.5 DoS Defend
DoS (Denial of Service) Attack is to occupy the network bandwidth maliciously by the network
attackers or the evil programs sending a lot of service requests to the Host, which incurs an
abnormal service or even breakdown of the network.
With DoS Defend function enabled, the switch can analyze the specific fields of the IP packets
and distinguish the malicious DoS attack packets. Upon detecting the packets, the switch will
discard the illegal packets directly and limit the transmission rate of the legal packets if the
over legal packets may incur a breakdown of the network. The switch can defend several types
of DoS attack listed in the following table.
DoS Attack Type Description
Land Attack The attacker sends a specific fake SYN packet to the destination
Host. Since both the source IP address and the destination IP
address of the SYN packet are set to be the IP address of the Host,
the Host will be trapped in an endless circle for building the initial
connection. The performance of the network will be reduced
extremely.
Scan SYNFIN The attacker sends the packet with its SYN field and the FIN field set
to 1. The SYN field is used to request initial connection whereas the
FIN field is used to request disconnection. Therefore, the packet of
this type is illegal. The switch can defend this type of illegal packet.
Xmascan The attacker sends the illegal packet with its TCP index, FIN, URG
and PSH field set to 1.
NULL Scan Attack The attacker sends the illegal packet with its TCP index and all the
control fields set to 0. During the TCP connection and data
transmission, the packets with all the control fields set to 0 are
considered as the illegal packets.
SYN packet with its
source port less than
1024
The attacker sends the illegal packet with its TCP SYN field set to 1
and source port less than 1024.
Blat Attack
The attacker sends the illegal packet with its source port and
destination port on Layer 4 the same and its URG field set to 1.
Similar to the Lan
d Attack, the system performance of the attacked
Host is reduced since the Host circularly attempts to build a
connection with the attacker.
Ping Flooding
The attacker floods the destination system with Ping broadcast
storm packets to forbid the system to
respond to the legal
communication.
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DoS Attack Type Description
SYN/SYN-ACK
Flooding
The attacker uses a fake IP address to send TCP request packets to
the Server. Upon receiving the request packets, the Server
responds with SYN-
ACK packets. Since the IP address is fake, no
response will be returned. The Server will keep on sending SYN-ACK
packets. If the attacker sends overflowing fake request packets, the
network resource will be occupied maliciously and the requests of
the legal clients will be denied.
Table 14-1 Defendable DoS Attack Types
14.5.1 DoS Defend
On this page, you can enable the DoS Defend type appropriate to your need.
Choose the menu Network Security→DoS Defend→DoS Defend to load the following page.
Figure 14-16 DoS Defend
Configuration Procedure:
Select one or more Defend Types to be enabled, and click Apply.
Entry Description:
Select:
Select the entry to enable the corresponding Defend Type.
Defend Type:
Displays the Defend Type name.
14.6 802.1X
The 802.1X protocol was developed by IEEE802 LAN/WAN committee to deal with the security
issues of wireless LANs. It was then used in Ethernet as a common access control mechanism
for LAN ports to solve mainly authentication and security problems.
802.1X is a port-based network access control protocol. It authenticates and controls devices
requesting for access in terms of the ports of LAN access control devices. With the 802.1X
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protocol enabled, a supplicant can access the LAN only when it passes the authentication,
whereas those failing to pass the authentication are denied when accessing the LAN.
Architecture of 802.1X Authentication
802.1X adopts a client/server architecture with three entities: a supplicant system, an
authenticator system, and an authentication server system, as shown in the following figure.
Figure 14-17 Architecture of 802.1X authentication
1. Supplicant System: The supplicant system is an entity in LAN and is authenticated by
the authenticator system. The supplicant system is usually a common user terminal
computer. An 802.1X authentication is initiated when a user launches client program on
the supplicant system. Note that the client program must support the 802.1X
authentication protocol.
2. Authenticator System: The authenticator system is usually an 802.1X-supported
network device, such as this TP-Link switch. It provides the physical or logical port for
the supplicant system to access the LAN and authenticates the supplicant system.
3. Authentication Server System: The authentication server system is an entity that
provides authentication service to the authenticator system. Normally in the form of a
RADIUS server. Authentication Server can store user information and serve to perform
authentication and authorization. To ensure a stable authentication system, an alternate
authentication server can be specified. If the main authentication server is in trouble,
the alternate authentication server can substitute it to provide normal authentication
service.
The Mechanism of an 802.1X Authentication System
IEEE 802.1X authentication system uses EAP (Extensible Authentication Protocol) to exchange
information between the supplicant system and the authentication server.
1. EAP protocol packets transmitted between the supplicant system and the
authenticator system are encapsulated as EAPOL packets.
2. EAP protocol packets transmitted between the authenticator system and the RADIUS
server can either be encapsulated as EAPOR (EAP over RADIUS) packets or be
terminated at authenticator system and the authenticator system then communicate
with RADIUS servers through PAP (Password Authentication Protocol) or CHAP
(Challenge Handshake Authentication Protocol) protocol packets.
3. When a supplicant system passes the authentication, the authentication server passes
the information about the supplicant system to the authenticator system. The
authenticator system in turn determines the state (authorized or unauthorized) of the
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controlled port according to the instructions (accept or reject) received from the
RADIUS server.
802.1X Authentication Procedure
An 802.1X authentication can be initiated by supplicant system or authenticator system. When
the authenticator system detects an unauthenticated supplicant in LAN, it will initiate the
802.1X authentication by sending EAP-Request/Identity packets to the supplicant. The
supplicant system can also launch an 802.1X client program to initiate an 802.1X
authentication through the sending of an EAPOL-Start packet to the switch.
This TP-Link switch can authenticate supplicant systems in EAP relay mode or EAP terminating
mode. The following illustration of these two modes will take the 802.1X authentication
procedure initiated by the supplicant system for example.
1. EAP Relay Mode
This mode is defined in 802.1X. In this mode, EAP-packets are encapsulated in higher level
protocol (such as EAPOR) packets to allow them successfully reach the authentication server.
This mode normally requires the RADIUS server to support the two fields of EAP: the
EAP-message field and the Message-authenticator field. This switch supports EAP-MD5
authentication way for the EAP relay mode. The following figure describes the basic EAP-MD5
authentication procedure.
Figure 14-18 EAP-MD5 Authentication Procedure
(1) A supplicant system launches an 802.1X client program via its registered user name and
password to initiate an access request through the sending of an EAPOL-Start packet to
the switch. The 802.1X client program then forwards the packet to the switch to start the
authentication process.
(2) Upon receiving the authentication request packet, the switch sends an
EAP-Request/Identity packet to ask the 802.1X client program for the user name.
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(3) The 802.1X client program responds by sending an EAP-Response/Identity packet to the
switch with the user name included. The switch then encapsulates the packet in a RADIUS
Access-Request packet and forwards it to the RADIUS server.
(4) Upon receiving the user name from the switch, the RADIUS server retrieves the user name,
finds the corresponding password by matching the user name in its database, encrypts the
password using a randomly-generated key, and sends the key to the switch through an
RADIUS Access-Challenge packet. The switch then sends the key to the 802.1X client
program.
(5) Upon receiving the key (encapsulated in an EAP-Request/MD5 Challenge packet) from the
switch, the client program encrypts the password of the supplicant system with the key
and sends the encrypted password (contained in an EAP-Response/MD5 Challenge packet)
to the RADIUS server through the switch. (The encryption is irreversible.)
(6) The RADIUS server compares the received encrypted password (contained in a RADIUS
Access-Request packet) with the locally-encrypted password. If the two match, it will then
send feedbacks (through a RADIUS Access-Accept packet and an EAP-Success packet) to
the switch to indicate that the supplicant system is authorized.
(7) The switch changes the state of the corresponding port to accepted state to allow the
supplicant system access the network. And then the switch will monitor the status of
supplicant by sending hand-shake packets periodically. By default, the switch will force the
supplicant to log off if it cannot get the response from the supplicant for two times.
(8) The supplicant system can also terminate the authenticated state by sending
EAPOL-Logoff packets to the switch. The switch then changes the port state from
accepted to rejected.
2. EAP Terminating Mode
In this mode, packet transmission is terminated at authenticator systems and the EAP packets
are mapped into RADIUS packets. Authentication and accounting are accomplished through
RADIUS protocol.
In this mode, PAP or CHAP is employed between the switch and the RADIUS server. This switch
supports the PAP terminating mode. The authentication procedure of PAP is illustrated in the
following figure.
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Figure 14-19 PAP Authentication Procedure
In PAP mode, the switch encrypts the password and sends the user name, the
randomly-generated key, and the supplicant system-encrypted password to the RADIUS
server for further authentication. Whereas the randomly-generated key in EAP-MD5 relay
mode is generated by the authentication server, and the switch is responsible to encapsulate
the authentication packet and forward it to the RADIUS server.
802.1X Timer
In 802.1 x authentication, the following timers are used to ensure that the supplicant system,
the switch, and the RADIUS server interact in an orderly way:
1. Supplicant system timer (Supplicant Timeout): This timer is triggered by the switch
after the switch sends a request packet to a supplicant system. The switch will resend
the request packet to the supplicant system if the supplicant system fails to respond in
the specified timeout period.
2. RADIUS server timer (Server Timeout): This timer is triggered by the switch after the
switch sends an authentication request packet to RADIUS server. The switch will resend
the authentication request packet if the RADIUS server fails to respond in the specified
timeout period.
3. Quiet-period timer (Quiet Period): This timer sets the quiet-period. When a supplicant
system fails to pass the authentication, the switch quiets for the specified period before
it processes another authentication request re-initiated by the supplicant system.
Guest VLAN
Guest VLAN function enables the supplicants that do not pass the authentication to access the
specific network resource.
By default, all the ports connected to the supplicants belong to a VLAN, i.e. Guest VLAN. Users
belonging to the Guest VLAN can access the resources of the Guest VLAN without being
authenticated. But they need to be authenticated before accessing external resources. After
passing the authentication, the ports will be removed from the Guest VLAN and be allowed to
access the other resources.
With the Guest VLAN function enabled, users can access the Guest VLAN to install 802.1X
client program or upgrade their 802.1x clients without being authenticated. If there is no
supplicant past the authentication on the port in a certain time, the switch will add the port to
the Guest VLAN.
With 802.1X function enabled and Guest VLAN configured, after the maximum number retries
have been made to send the EAP-Request/Identity packets and there are still ports that have
not sent any response back, the switch will then add these ports into the Guest VLAN
according to their link types. Only when the corresponding user passes the 802.1X
authentication, the port will be removed from the Guest VLAN and added to the specified VLAN.
In addition, the port will back to the Guest VLAN when its connected user logs off.
The 802.1X function is implemented on the Global Config and Port Config pages.
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14.6.1 Global Config
On this page, you can enable the 802.1X authentication function globally and control the
authentication process by specifying the Authentication Method, Guest VLAN and various
Timers.
Choose the menu Network Security→802.1X→Global Config to load the following page.
Figure 14-20 Global Config
Configuration Procedure:
Enable or disable 802.1X and the Accounting feature globally and click Apply.
14.6.2 Port Config
On this page, you can configure the 802.1X features for the ports basing on the actual network.
Choose the menu Network Security→802.1X→Port Config to load the following page.
Figure 14-21 Port Config
Configuration Procedure:
Select one or more ports and configure the relevant parameters. Then click Apply.
Entry Description:
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select your desired port for configuration. It is multi-optional.
Port:
Displays the port number.
Status:
Select Enable/Disable the 802.1X authentication feature for the
port.
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Guest VLAN:
Specify the VLAN ID needed to enable the Guest VLAN function,
ranging from 0 to 4093. 0 indicates that the Guest VLAN function
is disabled. The supplicants in the Guest VLAN can access the
specified network sources.
Port Control:
Specify the Control Mode for the port.
• Auto: In this mode, the port will normally work only after
passing the 802.1X Authentication.
• Force-Authorized: In this mode, the port can work normally
without passing the 802.1X Authentication.
• Force-Unauthorized: In this mode, the port is forbidden
working for its fixed unauthorized status.
Port Method:
Specify the Control Type for the port.
• MAC Based: Any client connected to the port should pass
the 802.1X Authentication for access.
• Port Based: All the clients connected to the port can access
the network on the condition that any one of the clients has
passed the 802.1X Authentication.
Max Request:
Specify the maximum number of attempts to send the
authentication packet. It ranges from 1 to 10 times and the
default is 10 times.
Tx Period
:
Specify the Dot1x transmit period on the specified port to
determine when an EAP-
Request/Identity packet is to be
transmitted. It ranges from 1 to 65535 seconds and the default
time is 30 seconds.
Guest VLAN
Period:
Specify the Guest VLAN Period of the port. Once set the Guest
VLAN on the port, the port will be included in the Guest VLAN
after the Guest VLAN Period. It ranges from 1 to 300 seconds
and the default time is 90 seconds.
Quiet Period:
Specify the Quiet Period. It ranges from 0 to 65535 seconds and
the default time is 60 seconds.
The quiet period starts after the authentication fails. During the
quiet period, the switch does not process authentication
requests from the same client.
Supp Timeout:
Specify the maximum time to wait for EAP-Response/
MD5-challenge packet from the supplicant before timing out the
supplicant.
It ranges from 1 to 65535 seconds and the default time is 30
seconds. If the switch does not receive any reply from the client
within the specified time, it will resend the request.
Authorized:
Displays the authentication status of the port.
LAG:
Displays the LAG to which the port belongs to.
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Note:
1. The 802.1X function takes effect only when it is enabled globally on the switch and for the
port.
2. The 802.1X function cannot be enabled for LAG member ports. That is, the port with
802.1X function enabled cannot be added to the LAG.
3. The 802.1X function should not be enabled for the port connected to the authentication
server. In addition, the authentication parameters of the switch and the authentication
server should be the same.
Configuration Procedure:
Step
Operation
Description
1 Connect an authentication
server to the switch and do
some configuration.
Required. Record the information of the client in the LAN
to the authentication server and configure the
corresponding authentication username and password
for the client.
2 Install the 802.1X client
software.
Required. For the client computers, you are required to
install the 802.1X software TpSupplicant provided on the
CD. The installation guide is also provided on the CD.
3 Configure the 802.1X
globally.
Required. By default, the global 802.1X function is
disabled. On the Network Security→802.1X→Global
Config page, configure the 802.1X function globally.
4 Configure the 802.1X for
the port.
Required. On the Network Security→802.1X→Port
Config page, configure the 802.1X feature for the port of
the switch basing on the actual network.
5 Configure the parameters
of the authentication server
Required. On the Network Security→AAA→Radius
Config page, configure the parameters of the server.
14.7 AAA
Overview
AAA stands for authentication, authorization and accounting. This feature is used to
authenticate users trying to log in to the switch or trying to access the administrative level
privilege.
Username and password pairs are used for login and privilege authentication. The
authentication can be processed locally in the switch or centrally in the RADIUS/TACACS+
server(s). The local authentication username and password pairs can be configured in 4.2 User
Management.
Applicable Access Application
The authentication can be applied on the following access applications: Console, Telnet, SSH
and HTTP.
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Authentication Method List
A method list describes the authentication methods and their sequence to authenticate a user.
The switch supports Login List for users to gain access to the switch, and Enable List for
normal users to gain administrative privileges.
The administrator can set the authentication methods in a preferable order in the list. The
switch uses the first method listed to authenticate users, if that method fails to respond, the
switch selects the next authentication method in the method list. This process continues until
there is a successful communication with a listed authentication method or until all defined
methods are exhausted. If authentication fails at any point in this circle, which means the
secure server or the local switch denies the user’s access, the authentication process stops
and no other authentication methods are attempted.
802.1X Authentication
802.1X protocol uses the RADIUS to provide detailed accounting information and flexible
administrative control over authentication process. The Dot1x List feature defines the RADIUS
server groups in the 802.1X authentication.
RADIUS/TACACS+ Server
User can configure the RADIUS/TACACS+ servers for the connection between the switch and
the server.
14.7.1 RADIUS Server Config
This page is used to configure the authentication servers running the RADIUS security
protocols.
Choose the menu Network Security→AAA→RADIUS Conifg to load the following page.
Configuration Procedure:
Configure the RADIUS server’s IP and other relevant parameters under the Server Config.
View, edit and delete the configured RADIUS servers in the Server List.
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Entry Description:
Server IP:
Enter the IP of the server running the RADIUS secure protocol.
Shared Key:
Enter the shared key between the RADIUS server and the switch.
The RADIUS server and the switch use the key string to encrypt
passwords and exchange responses.
Auth Port:
Specify the UDP destination port on the RADIUS server for
authentication requests.
Acct Port:
Specify the UDP destination port on the RADIUS server for
accounting requests.
Retransmit:
Specify the number of times a request is resent to a server if the
server does not respond.
Timeout:
Specify the time interval that the switch waits for the server to
reply before resending.
14.7.2 TACACS+ Server Config
This page is used to configure the authentication servers running the TACACS+ security
protocols.
Choose the menu Network Security→AAA→TACACS+ Conifg to load the following page.
Configuration Procedure:
Configure the TACACS+ server’s IP and other relevant parameters under the Server Config.
View, edit and delete the configured TACACS+ servers in the Server list.
Entry Description:
Server IP:
Enter the IP of the server running the TACACS+ secure protocol.
Shared Key:
Enter the shared key between the TACACS+ server and the
switch. The TACACS+ server and the switch use the key string to
encrypt passwords and exchange responses.
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Timeo
ut: Specify the time interval that the switch waits for the server to
reply before resending.
Server Port:
Specify the TCP port used on the TACACS+ server for AAA.
14.7.3 Authentication Method List Config
Before you configure AAA authentication on a certain application, you should define an
authentication method list first. An authentication method list describes the sequence and
authentication method to be queried to authenticate a user.
The switch uses the first method listed to authenticate users, if that method fails to respond,
the switch selects the next authentication method in the method list. This process continues
until there is a successful communication with a listed authentication method or until all defined
methods are exhausted. If authentication fails at any point in this circle, which means the
secure server or the local switch denies the user’s access, the authentication process stops
and no other authentication methods are attempted.
Choose the menu Network Security→AAA→Authentication List to load the following page.
Figure 14-22 Authentication Method List Config
Configuration Procedure:
1) Enter the method list name.
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2) Specify the authentication type as Login or Enable.
3) Configure the authencation method with priorities.
View and delete the configured method priority list in the Authentication Login Method List and
Authentication Enable Method List.
Entry Description:
Method List
Name:
Define a method list name.
List Type:
Specify the authentication type as Login or Enable. Login stands
for the Authentication Login Method List, and Enable stands for
the Authentication Enable Method list.
Pri1, Pri2, Pri3,
Pri4:
Specify the authentication methods in order. The next
authentication method is tried only if the previous method does
not respond, not if it fails.
local: Use the local database in the switch for authentication.
enable: Use the locally configured Enable password to verify the
user's credentials.
none: No authentication is used.
line: Use the locally configured Line password to verify the user's
credentials.
radius: Use the remote RADIUS server/server groups for
authentication.
tacacs: Use the remote TACACS+ server/server groups for
authentication.
deny: Deny the authentication. Only Enable Method supports this
option.
Tips:
If the Enable password is verified on the remote RADIUS server, the switch will send the Enable
authentication with the default username as $enab15$. If the Enable password is verified locally,
the Enable password should be previously set by the admin users using the command lines. For
more details please refer to the command enable password in the Command Line Interface
Guide on the resource CD.
14.7.4 Application Authentication List Config
Users can configure authentication method lists on the following access applications: console,
telnet, ssh and http.
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Choose the menu Network Security→AAA→Global Config to load the following page.
Figure 14-23 Application Authentication Settings
Configuration Procedure:
1) Select the application module.
2) Configure the authentication method list from the Login List drop-down menu. This option
defines the authentication method for users accessing the switch.
3) Configure the authentication method list from the Enable List drop-down menu. Thisoption
defines the authentication method for users requiring the administrator privilege.
Entry Description:
Module:
Lists of the configurable applications on the switch.
Login List:
Configure an application for the login utilizing a previously
configured method list.
Enable List:
Configure an application to promote the user level to admin-level
users utilizing a previously configured method list.
14.7.5 802.1X Authentication Server Config
This page is used to configure the RADIUS server group used in 802.1X Authentication and
Accounting.
Choose the menu Network Security→AAA→Dot1x List to load the following page.
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Configuration Procedure:
1) Configure the 802.1X function globally and on the supplicant-connected port. Please refer
to 802.1X for more details.
2) Configure the 802.1X Aunthentication RADIUS server group in the Authentication Dot1x
Method List Table.
3) Configure the 802.1X Accounting RADIUS server group in the Accounting Dot1x Method
List Table.
14.7.6 Default Settings
Feature Default Settings
RADIUS server
Auth port is 1812.
Acct port is 1813.
Retransmit is 4 times.
Timeout is 5 seconds.
TACACA+ server
Communication port is 49.
Timeout is 5 seconds.
Authentication login method list
The list contains local, and the default login
username and passwords are both admin.
Authentication enable method
list
The list is empty, which means users can prompt
to administrator privilege without password.
Access application
authentication
The application console/telnet/ssh/http use the
default Login List and default Enable list.
802.1X authentication server
and accounting server
802.1X authentic
ation uses the radius server
group. 802.1X accounting uses the radius server
group.
Return to CONTENTS
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Chapter 15 SNMP
SNMP Overview
SNMP (Simple Network Management Protocol) has gained the most extensive application on
the UDP/IP networks. SNMP provides a management frame to monitor and maintain the
network devices. It is used for automatically managing the various network devices no matter
the physical differences of the devices. Currently, the most network management systems are
based on SNMP.
SNMP is simply designed and convenient for use with no need of complex fulfillment
procedures and too much network resources. With SNMP function enabled, network
administrators can easily monitor the network performance, detect the malfunctions and
configure the network devices. In the meantime, they can locate faults promptly and implement
the fault diagnosis, capacity planning and report generating.
SNMP Management Frame
SNMP management frame includes three network elements: SNMP Management Station,
SNMP Agent and MIB (Management Information Base).
SNMP Management Station: SNMP Management Station is the workstation for running the
SNMP client program, providing a friendly management interface for the administrator to
manage the most network devices conveniently.
SNMP Agent: Agent is the server software operated on network devices with the responsibility
of receiving and processing the request packets from SNMP Management Station. In the
meanwhile, Agent will inform the SNMP Management Station of the events whenever the
device status changes or the device encounters any abnormalities such as device reboot.
MIB: MIB is the set of the managed objects. MIB defines a few attributes of the managed
objects, including the names, the access rights, and the data types. Every SNMP Agent has its
own MIB. The SNMP Management station can read/write the MIB objects basing on its
management right.
SNMP Management Station is the manager of SNMP network while SNMP Agent is the
managed object. The information between SNMP Management Station and SNMP Agent are
exchanged through SNMP (Simple Network Management Protocol). The relationship among
SNMP Management Station, SNMP Agent and MIB is illustrated in the following figure.
Figure15-1 Relationship among SNMP Network Elements
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SNMP Versions
This switch supports SNMP v3, and is compatible with SNMP v1 and SNMP v2c. The SNMP
versions adopted by SNMP Management Station and SNMP Agent should be the same.
Otherwise, SNMP Management Station and SNMP Agent cannot communicate with each other
normally. You can select the management mode with proper security level according to your
actual application requirement.
SNMP v1: SNMP v1 adopts Community Name authentication. The community name is used to
define the relation between SNMP Management Station and SNMP Agent. The SNMP packets
failing to pass community name authentication are discarded. The community name can limit
access to SNMP Agent from SNMP NMS, functioning as a password.
SNMP v2c: SNMP v2c also adopts community name authentication. It is compatible with SNMP
v1 while enlarges the function of SNMP v1.
SNMP v3: Basing on SNMP v1 and SNMP v2c, SNMP v3 extremely enhances the security and
manageability. It adopts VACM (View-based Access Control Model) and USM (User-Based
Security Model) authentication. The user can configure the authentication and the encryption
functions. The authentication function is to limit the access of the illegal user by authenticating
the senders of packets. Meanwhile, the encryption function is used to encrypt the packets
transmitted between SNMP Management Station and SNMP Agent so as to prevent any
information being stolen. The multiple combinations of authentication function and encryption
function can guarantee a more reliable communication between SNMP Management station
and SNMP Agent.
MIB Introduction
To uniquely identify the management objects of the device in SNMP messages, SNMP adopts
the hierarchical architecture to identify the managed objects. It is like a tree, and each tree
node represents a managed object, as shown in the following figure. Thus the object can be
identified with the unique path starting from the root and indicated by a string of numbers. The
number string is the Object Identifier of the managed object. In the following figure, the OID of
the managed object B is {1.2.1.1}. While the OID of the managed object A is {1.2.1.1.5}.
Figure15-2 Architecture of the MIB tree
SNMP Configuration Outline
1. Create View
The SNMP View is created for the SNMP Management Station to manage MIB objects. The
managed object, uniquely identified by OID, can be set to under or out of the management of
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SNMP Management Station by configuring its view type (included/excluded). The OID of
managed object can be found on the SNMP client program running on the SNMP Management
Station.
2. Create SNMP Group
After creating the SNMP View, it’s required to create an SNMP Group. The Group Name,
Security Model and Security Level compose the identifier of the SNMP Group. The Groups with
these three items the same are considered to be the same. You can configure SNMP Group to
control the network access by providing the users in various groups with different
management rights via the Read View, Write View and Notify View.
3. Create SNMP User
The User configured in an SNMP Group can manage the switch via the client program on
management station. The specified User Name and the Auth/Privacy Password are used for
SNMP Management Station to access the SNMP Agent, functioning as the password.
SNMP module is used to configure the SNMP function of the switch, including three submenus:
SNMP Config, Notification and RMON.
15.1 SNMP Config
The SNMP Config can be implemented on the Global Config, SNMP View, SNMP Group,
SNMP User and SNMP Community pages.
15.1.1 Global Config
Choose the menu SNMP → SNMP Config → Global Config to load the following page.
Figure 15-3 Global Config
Configuration Procedure:
Configure the local engine ID and remote engine ID.
Entry Description:
Local Engine
Local Engine
ID:
Specify the Switch’s Engine ID for the remote clients. The
Engine ID is a unique alphanumeric string used to identify the
SNMP engine on the Switch.
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Remote Engine
Remote Engine ID:
Specify the Remote Engine ID for Switch. The Engine ID is a
unique alp
hanumeric string used to identify the SNMP engine
on the remote device which receives informs from Switch.
Note:
1. The total hexadecimal characters of Engine ID should be even.
2. Change the Local Engine ID could make local user and community invaild, please re-create
new local users or community.
3. Change the Remote Engine ID could make remote user invaild, please re-create new
remote users.
15.1.2 SNMP View
The OID (Object Identifier) of the SNMP packets is used to describe the managed objects of the
switch, and the MIB (Management Information Base) is the set of the OIDs. The SNMP View is
created for the SNMP management station to manage MIB objects.
Choose the menu SNMP → SNMP Config → SNMP View to load the following page.
Figure15-4 SNMP View
Configuration Procedure:
Create an SNMP view, and configure the content of the view.
Entry Description:
View Config
View Name:
Give a name to the view for identification. Each v
iew can
include several entries with the same name.
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MIB Object ID:
Enter the Object Identifier (OID) for the entry of view.
View Type:
Select the type for the view entry.
• Include: The view entry can be manage
d by the SNMP
management station.
• Exclude: The view entry cannot
be managed by the
SNMP management station.
View Table
Select:
Select the desired entry to delete the corresponding view.
All the entries of a view will be deleted together.
View Name:
Displays the name of the view entry.
View Type:
Displays the type of the view entry.
MIB Object ID:
Displays the OID of the vew entry.
15.1.3 SNMP Group
On this page, you can configure SNMP Group to control the network access by providing the
users in various groups with different management rights via the Read View, Write View and
Notify View.
Choose the menu SNMP → SNMP Config → SNMP Group to load the following page.
Figure15-5 SNMP Group
Configuration Procedure:
1) Set the group name and security model. If you choose SNMPv3 as the security model, you
need to further configure security level.
2) Set the read, write and notify view of the SNMP Group. Click Create.
Entry Description:
Group Config
Group Name:
Enter the SNMP Group name. The Group Name, Security Model
and Security Level compose the identifier of the SNMP Group.
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These three items of the Users in one group should be the
same.
Security Model:
Select the Security Model for the SNMP Group.
• v1:
SNMPv1 is defined for the group. In this model, the
Community Name is used for authentication. SNMP v1 can
be configured on the SNMP Community page directly.
• v2c:
SNMPv2c is defined for the group. In this model, the
Community Name is used for authentication. SNMP v2c can
be configured on the SNMP Community page directly.
• v3: SNMPv3 is defined for the group. In this model, the
USM
mechanism is used for authentication. If SNMPv3 is
enabled, the Security Level field is enabled for
configuration.
Security Level:
Select the Security Level for the SNMP v3 Group.
• noAuthNoPriv:
No authentication and no privacy security
level is used.
• authNoPriv: Only the authentication security level is used.
• authPriv:
Both the authentication and the privacy security
levels are used.
Read View:
Select the View to be the Read View. The management access
is restricted to read-only, and changes cannot be
made to the
assigned SNMP View.
Write View:
Select the View to be the Write View. The management access
is writing only and changes can be made to the assigned SNMP
View. The View defined both as the Read View and the Write
View can be read and modified.
Notify View:
Select the View to be the Notify View. The management station
can receive notification
messages of the assigned SNMP view
generated by the switch's SNMP agent.
Group Table
Select:
Select the desired entry to delete the corresponding group.
It's
multi-optional.
Group Name:
Displays the Group Name here.
Security Model:
Displays the Security Model of the group.
Security Level:
Displays the Security Level of the group.
Read View:
Displays the Read View name in the entry.
Write View:
Displays the Write View name in the entry.
Notify View:
Displays the Notify View name in the entry.
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Operation:
Click the Edit
button to modify the Views in the entry and click
the Modify button to apply.
Note:
Every Group should contain a Read View. The default Read View is Default.
15.1.4 SNMP User
The User in an SNMP Group can manage the switch via the management station software. The
User and its Group have the same security level and access right. You can configure the SNMP
User on this page.
Choose the menu SNMP → SNMP Config → SNMP User to load the following page.
Figure15-6 SNMP User
Configuration Procedure:
1) Specify the user name, user type and the group which the user belongs to.
2) Set the security model. If you have chosen authNoPriv or authPriv as the security level, you
need to set corresponding Auth Mode or Privacy Mode.
Entry Description:
User Config
User Name:
Enter the User Name here.
User Type:
Select the type for the User.
• Local User: Indicates that the
user is connected to a
local SNMP engine.
• Remote User:
Indicates that the user is connected to a
remote SNMP engine.
Group Name:
Select the Group Name of the User. The User is classified
to the corresponding Group according to its Group Name,
Security Model and Security Level.
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Security Level:
Select the Security Level for the SNMP v3 User.
Auth Mode:
Select the Authentication Mode for the SNMP v3 User.
• None: No authentication method is used.
• MD5:
The port authentication is performed via
HMAC-MD5 algorithm.
• SHA: The port authentication is performed via SHA
(Secure Hash Algorithm)
. This authentication mode
has a higher security than MD5 mode.
Auth Password:
Enter the password for authentication.
Privacy Mode:
Select the Privacy Mode for the SNMP v3 User.
• None: No privacy method is used.
•
DES: DES encryption method is used.
Privacy Password:
Enter the Privacy Password.
User Table
Select:
Select the desired entry to delete the corresponding User.
It is multi-optional.
User Name:
Displays the name of the User.
User Type:
Displays the User Type.
Group Name:
Displays the Group Name of the User.
Auth Mode:
Displays the Authentication Mode of the User.
Privacy Mode:
Displays the Privacy Mode of the User.
Engine ID:
Displays the Engine ID of the User.
Op
eration: Click the Edit
button to modify the Group of the User and
click the Modify button to apply.
Note:
The SNMP User and its Group should have the same Security Level.
15.1.5 SNMP Community
SNMP v1 and SNMP v2c adopt community name authentication. The community name can limit
access to the SNMP agent from SNMP network management station, functioning as a
password. If SNMP v1 or SNMP v2c is employed, you can directly configure the SNMP
Community on this page without configuring SNMP Group and User.
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Choose the menu SNMP → SNMP Config → SNMP Community to load the following page.
Figure 15-7 SNMP Community
Configuration Procedure:
Set the community name, access rights and the related view. Click Create.
Entry Description:
Community Config
Community Name:
Enter the Community Name here.
Access:
Defines the access rights of the community.
• read-only:
Management right of the Community is
restricted to read-only, and changes cannot be made to
the corresponding View.
• read-write: Management right of the Community is
read-
write and changes can be made to the
corresponding View.
MIB View:
Select the MIB View for the community to access.
IP Address:
Enter the IP address which could connect the SNMP server. If
null, all user could connect the SNMP server.
Community Table
Select:
Select the desired entry to delete the corresponding
Community. It is multi-optional.
Community Name:
Displays the Community Name here.
Access:
Displays the right of the Community to access the View.
MIB View:
Displays the Views which the Community can access.
IP Address:
Displays the IP address of the SNMP Community.
Operation:
Click the
Edit
button to modify the MIB View and the Access
right of the Community, and then click the
Modify butto
n to
apply.
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Note:
The default MIB View of SNMP Community is Default.
Configuration Procedure:
If SNMPv3 is employed, please take the following steps:
Step
Operation
Description
1 Create SNMP View. Required. On the SNMP→SNMP Config→SNMP
View page, create SNMP View of the management
agent. The default View Name is Default and the
default OID is 1.
2 Create SNMP Group. Required. On the SNMP→SNMP Config→SNMP
Group page, create SNMP Group for SNMPv3 and
specify SNMP Views with various access levels for
SNMP Group.
3 Create SNMP User. Required. On the SNMP→SNMP Config→SNMP
User page, create SNMP User in the Group and
configure the auth/privacy mode and auth/privacy
password for the User.
If SNMPv1 or SNMPv2c is employed, please take the following steps:
Step
Operation
Description
1 Create SNMP View. Required. On the SNMP→SNMP Config→SNMP
View page, create SNMP View of the management
agent. The default View Name is viewDefault and the
default OID is 1.
2
Configure
access level
for the User.
Create SNMP
Community
directly.
Required alternatively.
Create SNMP Community directly.
On the SNMP→SNMP Config→SNMP
Community page, create SNMP Community
based on SNMP v1 and SNMP v2c.
Create SNMP Group and SNMP User.
Similar to the configuration way based on
SNMPv3, you can create SNMP Group and
SNMP User of SNMP v1/v2c. The User name
can limit access to the SNMP agent from
SNMP network management station,
functioning as a community name. The users
can manage the device via the Read View,
Write View and Notify View defined in the
SNMP Group.
Create SNMP
Group and SNMP
User.
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15.2 Notification
With the Notification function enabled, the switch can initiatively report to the management
station about the important events that occur on the Views (e.g., the managed device is
rebooted), which allows the management station to monitor and process the events in time.
The notification information includes the following two types:
Trap：Trap is the information that the managed device initiatively sends to the Network
management station without request.
Inform：Inform packet is sent to inform the management station and ask for the reply. The
switch will resend the inform request if it doesn’t get the response from the management
station during the Timeout interval, and it will terminate resending the inform request if the
resending times reach the specified Retry times. The Inform type, employed on SNMPv2c and
SNMPv3, has a higher security than the Trap type.
The Notification can be configured on the Notification Config and Traps Config pages.
15.2.1 Notification Config
On this page, you can configure the notification function of SNMP.
Choose the menu SNMP → Notification → Notification Config to load the following page.
Figure15-8 Notification Config
Configuration Procedure:
1) Specify the IP address of the host, the UDP port that sends notifications, and choose the IP
mode according to the network environment.
2) Specify the user name or community name used by the NMS, and configure the security
model and security level based on the settings of the user or community.
3) Choose a notification type based on the SNMP version. If you choose the Inform type, you
need to set retry times and timeout interval.
4) Click Create.
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Entry Description:
Host Config
IP Address:
If you set the IP Mode
to IPv4, specify an IPv4 address for
the host.
If you set the IP Mode to IPv6, specify an
IPv6 address for
the host.
UDP Port:
Specify a UDP port on the host to send notifications. The
default is port 162. For communication security, we
recommend that you change the port number under the
condition that communications on other UDP ports are no
t
affected.
IP Mode:
Choose an IP mode for the host, which should be
coordinated with the IP Address.
User:
Specify the user name or community name used by the NMS.
Security Model:
Choose the corresponding SNMP version for the NMS.
The version should be
consistent with settings of the user or
community.
v1: The NMS uses SNMPv1.
v2: The NMS uses SNMPv2c.
v3: The NMS uses SNMPv3.
Security Level:
Choose the security level for the NMS that uses SNMPv3.
The setting should be consistent with that of the speci
fied
user or community.
noAuthNoPriv: No authentication mode or privacy mode is
applied to check or encrypt packets.
authNoPriv: An authentication mode is applied to check
packets, but no privacy mode to encrypt packets.
authPriv: An authentication mode an
d a privacy mode are
applied to check and encrypt packets.
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Type:
Choose a notification type for the NMS that uses SNMPv2c or
SNMPv3; the default type is Trap.
•
Trap: Set the switch to send Trap messages to the NMS.
When the NMS receives a trap message, it
will not send a
response to the switch. Thus the switch cannot
determine whether the trap is received or not, and the
trap that is not received will not be resent.
•
Inform: Set the switch to send Inform messages to the
NMS. When the NMS receives an Inform m
essage, it
sends a response to the switch. If the switch does not
receive a response within the Timeout interval, it will
resend the Inform message. Therefore, Informs are more
reliable than Traps.
Retry:
Set the retry times for Informs; the default is 3. The switch will
resend the Inform message if it does not receive response
from the NMS within the timeout interval. It will stop sending
Inform messages when the retry time reaches the limit.
Timeout:
Set the length of time that the switch waits for a re
sponse
from the NMS after sending an inform message; the default is
100 seconds. Set the length of time that the switch waits for
a response from the NMS after sending an inform message;
the default is 100 seconds.
Notification Table
Select:
Select the de
sired entry to delete the corresponding
management station.
IP Address:
Displays the IP Address of the management host.
UDP Port:
Displays the UDP port used to send notifications.
User:
Displays the User name of the management station.
Security Model:
Displays the Security Model of the management station.
Security Level:
Displays the Security Level for the SNMP v3 User.
Type:
Displays the type of the notifications.
Retry:
Displays the maximum time for the switch to wait for the
response from the man
agement station before resending a
request.
Timeout:
Displays the amount of times the switch resends an inform
request.
Operation:
Click the Edit
button to modify the corresponding entry and
click the Modify button to apply.
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15.2.2 Traps Config
On this page, you can configure the traps of SNMP.
Choose the menu SNMP → Notification → Traps Config to load the following page.
Figure15-9 Traps Config
Configuration Procedure:
Configure traps you desire to send to the SNMP server. Click Apply.
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Entry Description:
SNMP Traps
Multiple User:
Generates a trap when
the same user ID is logged into the
switch more than once at the same time.
CPU Thresholds:
Generates a trap when the CPU utilization is over 80%.
Spanning Tree:
Generates a trap when the status of STP changes.
Link Status
: Generates a trap when t
he up/down status of an interface
changes.
Storm Control:
Generates a trap
when the multicast or broadcast rate
exceeds the predefined value.
Mbuf Thresholds
Generates a trap when the memory utilization is over 80%.
Mac Lock
Viol
ation:
Generates a trap when
a packet with a disallowed MAC
address is received on a locked port.
Dot1q:
Generates a trap when creating or deleting a VLAN.
Inventory:
Generates a trap for Inventory.
V
rrp:
Generates a trap for Virtual Routing Redundancy Protocol
(VRRP) changes.
Pim:
Generates a trap for Protocol-
Independent Multicast (PIM)
changes.
Fan:
Generates a trap for fan.
Power:
Generates a trap for power.
Temperature:
Generates a trap for temperature.
OSPF Traps
Virt If State
Change:
Generates a trap when virtual interface state changes.
Nbr State
Change:
Generates a trap when non-virtual neighbour state changes.
Virt Nbr State
Change:
Generates a trap when virtual neighbour state changes.
If Config Error
: Generates a trap when configure
mismatch errors occur on
non-virtual interfaces.
Virt Config Error
: Generates a trap when configure
mismatch errors occur on
virtual interfaces.
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If Auth Failure:
Generates a trap when authentication failures occur on
non-virtual interfaces.
Virt If Auth
Failure
:
Generates a trap when authentication failures occur on virtual
interfaces.
Rx Bad Packet
: Generates a trap when packet parse failures occur on
non-virtual interfaces.
Virt If Rx Bad
Packet
:
Generates a trap when packet parse failures occur
on virtual
interfaces.
Tx Retransmit
: Generates a trap when packet retransmission occur on
non-virtual interfaces.
Virt If Tx
Retransmit
:
Generates a trap when packet retransmission occur on virtual
interfaces.
Originate Lsa:
Generates a trap when OSPF originates a new LSA.
Max Age lsa
: Generates a trap when one of the LSAs in the link-state
database has aged to maxage.
Ls Db Overflow
: Generates a trap when the number of LSAs in the link-state
database overflows.
Ls Db
Approaching
Overflow:
Generates a trap when the number of LSAs in the link-state
database is approaching overflow.
If State Change:
Generates a trap when non-virtual interface state changes.
Port Traps
Port:
Displays the port number of the switch.
Link status:
Enable or disable link status traps for the desired port.
Allow SNMP Linkup and Linkdown traps.
15.3 RMON
RMON (Remote Monitoring) basing on SNMP (Simple Network Management Protocol)
architecture, functions to monitor the network. RMON is currently a commonly used network
management standard defined by Internet Engineering Task Force (IETF), which is mainly used
to monitor the data traffic across a network segment or even the entire network so as to enable
the network administrator to take the protection measures in time to avoid any network
malfunction. In addition, RMON MIB records network statistics information of network
performance and malfunction periodically, based on which the management station can
monitor network at any time effectively. RMON is helpful for network administrator to manage
the large-scale network since it reduces the communication traffic between management
station and managed agent.
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RMON Group
This switch supports the following four RMON Groups defined on the RMON standard
(RFC1757): History Group, Event Group, Statistic Group and Alarm Group.
RMON Group
Function
History Group
After a history group is configured, the switch collects and records
network statistics information periodically, based on whi
ch the
management station can monitor network effectively.
Event Group Event Group is used to define RMON events. Alarms occur when an event
is detected.
Statistic Group Statistic Group is set to
monitor the statistic of alarm variables on the
specific ports.
Alarm Group Alarm Group is configured to monitor the specific alarm variables. When
the value of a monitored variable exceeds the threshold, an alarm event is
generated, which triggers the switch to act in the set way.
The RMON Groups can be configured on the History, Event and Alarm pages.
15.3.1 History
On this page, you can configure the History Group for RMON.
Choose the menu SNMP → RMON → History to load the following page.
Figure 15-10 History Control
Configuration Procedure:
Configure the history group for RMON. Click Create.
Entry Description:
Index:
Specify the index number of the entry.
Port:
Specify the port from which the history samples were taken, in
format as 1/0/1.
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Interval:
Specify the interval to take samplings from the port, ranging
from 10 to 3600 seconds. The default is 1800 seconds.
Max Buckets
Displays the maximu
m number of buckets desired for the RMON
history group of statistics, ranging from 1 to 65535. The default
is 50 buckets.
Owner:
Enter the name of the device or user that defines the entry.
Operation:
Click “Edit” to edit the history group entry.
15.3.2 Event
On this page, you can configure the RMON events.
Choose the menu SNMP → RMON → Event to load the following page.
Figure15-11 Event Config
Configuration Procedure:
Configure the event group for RMON. Click “Create”.
Entry Description:
Index:
Displays the index number of the entry.
Community:
Enter the name of the user or the community to which the
event belongs.
Description:
Give a description to the event for identification.
Type:
Select the event type, which determines the act way of the
network device in response to an event.
• None: No processing.
• Log: Logging the event.
• Notify: Sending trap messages to the management
station.
• Log&Notify: Logging the event and sending trap
messages to the management station.
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Owner:
Enter the name of the device or user that defined the entry.
Operation:
Click “Edit” to edit the event group entry.
15.3.3 Alarm
On this page, you can configure Statistic Group and Alarm Group for RMON.
Choose the menu SNMP → RMON → Alarm to load the following page.
Figure 15-12 Alarm Config
Configuration Procedure:
1) Specify the index number of the alarm group, choose a variable to be monitored, and
associate the entry with a statistics entry.
2) Set the sample type, the alarm type, the rising and falling event action and the
corresponding threshold of the entry. Enter the alarm interval time.
3) Enter the owner name.
4) Click Create.
Entry Description:
Index:
Displays the index number of the entry.
Variable:
Select the alarm variables from the drop-down list.
Port
Specify which port to collect the statistics.
Sample Type:
Specify the sampling method for the selected variable and
comparing the value against the thresholds.
• Absolute: Compares the values direct
ly with the
thresholds at the end of the sampling interval.
• Delta:
Subtracts the last sampled value from the current
value. The difference in the values is compared to the
threshold.
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Alarm Type:
Specify the type of the alarm.
• Rising: When the sampled valu
e exceeds the Rising
Threshold, an alarm event is triggered.
• Falling:
When the sampled value is under the Falling
Threshold, an alarm event is triggered.
• All:
The alarm event will be triggered either the sampled
value exceeds the Rising Threshold or is under the Falling
Threshold.
Rising Event:
Select the index of the corresponding event which will be
triggered if the sampled value is larger than the rising
Threshold.
Rising Threshold:
Enter the rising counter value that triggers the rising threshold
alarm, ranging from 1 to 2147483647.
Falling Event:
Select the index of the corresponding event which will be
triggered if the sampled value is lower than the Falling
Threshold.
Falling Threshold:
Enter the falling counter value that triggers the falling
threshold alarm, ranging from 1 to 2147483647.
Interval:
Enter the alarm interval time in seconds, ranging from 10 to
3600.
Owner:
Enter the name of the device or user that defines the entry.
Operation:
Click “Edit” to edit the alarm group entry.
Note:
When alarm variables exceed the Threshold on the same direction continuously for several
times, an alarm event will only be generated on the first time, that is, the Rising Alarm and
Falling Alarm are triggered alternately for that the alarm following to Rising Alarm is certainly a
Falling Alarm and vice versa.
Return to CONTENTS
385
Chapter 16 LLDP
LLDP (Link Layer Discovery Protocol) is a Layer 2 protocol that is used for network devices to
advertise their own device information periodically to neighbors on the same IEEE 802 local
area network. The advertised information, including details such as device identification,
capabilities and configuration settings, is represented in TLV (Type/Length/Value) format
according to the IEEE 802.1ab standard, and these TLVs are encapsulated in LLDPDU (Link
Layer Discovery Protocol Data Unit). The LLDPDU distributed via LLDP is stored by its
recipients in a standard MIB (Management Information Base), making it possible for the
information to be accessed by a Network Management System (NMS) using a management
protocol such as the Simple Network Management Protocol (SNMP).
An IETF Standard MIB, as well as a number of vendor specific MIBs, have been created to
describe a network's physical topology and associated systems within that topology. However,
there is no standard protocol for populating these MIBs or communicating this information
among stations on the IEEE 802 LAN. LLDP protocol specifies a set. The device running LLDP
can automatically discover and learn about the neighbors, allowing for interoperability between
the network devices of different vendors. This protocol allows two systems running different
network layer protocols to learn about each other.
The LLDP information can be used by SNMP applications to simplify troubleshooting, enhance
network management, and maintain an accurate network topology.
LLDPDU Format
Each LLDPDU includes an ordered sequence of three mandatory TLVs followed by one or more
optional TLVs plus an End of LLDPDU TLV, as shown in the figure below. Chassis ID TLV, Port ID
TLV, TTL TLV and End TLV are the four mandatory TLVs for a LLDPDU. Optional TLVs provide
various details about the LLDP agent advertising them and they are selected by network
management.
The maximum length of the LLDPDU shall be the maximum information field length allowed by
the particular transmission rate and protocol. In IEEE 802.3 MACs, for example, the maximum
LLDPDU length is the maximum data field length for the basic, untagged MAC frame (1500
octets).
LLDP Working Mechanism
1) LLDP Admin Status
The transmission and the reception of LLDPDUs can be separately enabled for every port,
making it possible to configure an implementation to restrict the port either to transmit
only or receive only, or to allow the port to both transmit and receive LLDPDUs. Four LLDP
admin statuses are supported by each port.
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Tx&Rx: the port can both transmit and receive LLDPDUs.
Rx_Only: the port can receive LLDPDUs only.
Tx_Only: the port can transmit LLDPDUs only.
Disable: the port cannot transmit or receive LLDPDUs.
2) LLDPDU transmission mechanism
If the ports are working in TxRx or Tx mode, they will advertise local information by
sending LLDPDUs periodically.
If there is a change in the local device, the change notification will be advertised. To
prevent a series of successive LLDPDUs transmissions during a short period due to
frequent changes in local device, a transmission delay timer is set by network
management to ensure that there is a defined minimum time between successive
LLDP frame transmissions.
If the LLDP admin status of the port is changed from Disable/Rx to TxRx/Tx, the Fast
Start Mechanism will be active, the transmit interval turns to be 1 second, several
LLDPDUs will be sent out, and then the transmit interval comes back to the regular
interval.
3) LLDPDU receipt mechanism
When a port is working in TxRx or Rx mode, the device will check the validity of the
received LLDPDUs and the attached TLVs, save this neighbor information to the local
device and then set the aging time of this information according to the TTL value of TTL
(Time To Live) TLV. Once the TTL is 0, this neighbor information will be aged out
immediately.
The aging time of the local information in the neighbor device is determined by TTL. Hold
Multiplier is a multiplier on the Transmit Interval that determines the actual TTL value used in an
LLDPDU. TTL = Hold Multiplier * Transmit Interval.
TLV
TLV refers to Type/Length/Value and is contained in a LLDPDU. Type identifies what kind of
information is being sent, Length indicates the length of information string in octets and Value
is the actual information to be sent. The basic TLV Format is shown as follows:
Each TLV is identified by a unique TLV type value that indicates the particular kind of
information contained in the TLV.
The following table shows the details about the currently defined TLVs.
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TLV Type TLV Name Description Usage in
LLDPDU
0 End of LLDPDU Mark the end of the TLV sequence in LLDPDUs.
Any information following an End Of LLDPDU
TLV shall be ignored.
Mandatory
1 Chassis ID
Identifies the Chassis address of the
connected device.
Mandatory
2 Port ID Identifies the specific port that transmitted the
LLDP frame. When the device does not
advertise MED TLV, this field displays the port
name of the port; when the device advertises
MED TLV, this field displays the MAC address
of the port.
Mandatory
3 Time To Live
Indicates the number of seconds that the
neighbor device is to regard the local
information to be valid.
Mandatory
4 Port
Description
Identifies the description string of the port. Optional
5
System Name
Identifies the system name.
Optional
6 System
Description
Identifies the system description. Optional
7 System
Capabilities
Identifies the main functions of the system and
the functions enabled.
Optional
8 Management
Address
Identifies the management IP address, the
corresponding interface number and OID
(Object Identifier). The management IP address
is specified by the user.
Optional
127 Organizationally
Specific
All
ows different organizations, such as IEEE
802.1, IEEE 802.3, IETF, as well as individual
software and equipment vendors, to define
TLVs that advertise information to remote
device.
Optional
Optional TLVs are grouped into two categories including basic management TLV and
Organizationally-specific TLV.
Basic Management TLV
A set of TLVs considered to be basic to the management of the network stations are required
for all LLDP implementations.
Organizationally Specific TLV
Different organizations have defined various TLVs. For instance, Port VLAN ID TLV, Port and
Protocol VLAN ID TLV, VLAN Name TLV And Protocol Identity TLV are defined by IEEE 802.1,
while MAC/PHY Configuration/Status TLV, Power Via MDI TLV, Link Aggregation TLV and
Maximum Frame TLV are defined by IEEE 802.3.
388
Note:
For detailed introduction of TLV, please refer to IEEE 802.1ab standard.
In TP-Link switch, the following LLDP optional TLVs are supported.
Port Description TLV
The Port Description TLV allows network management to
advertise the IEEE 802 LAN station's port description.
System Capabilities TLV The System Capabilities TLV identifies the primary functions of
the system and whether or not these primary functions are
enabled.
System Description TLV The System Description TLV allows n
etwork management to
advertise the system's description, which should include the full
name and version identification of the system's hardware type,
software operating system, and networking software.
System Name TLV The System Name TLV allows network ma
nagement to
advertise the system's assigned name, which should be the
system's fully qualified domain name.
Management Address
TLV
The Management Address TLV identifies an address
associated with the local LLDP agent that may be used to reach
higher entities to assist discovery by network management.
Port VLAN ID TLV
The Port VLAN ID TLV allows a VLAN bridge port to advertise
the port's VLAN identifier (PVID) that will be associated with
untagged or priority tagged frames.
Port And Protocol VLAN
ID TLV
T
he Port And Protocol VLAN ID TLV allows a bridge port to
advertise a port and protocol VLAN ID.
VLAN Name TLV The VLAN Name TLV allows an IEEE 802.1Q-
compatible IEEE
802 LAN station to advertise the assigned name of any VLAN
with which it is configured.
Link Aggregation TLV The Link Aggregation TLV indicates whether the link is capable
of being aggregated, whether the link is currently in an
aggregation, and if in an aggregation, the port identification of
the aggregation.
Max Frame Size TLV The Maximum
Frame Size TLV indicates the maximum frame
size capability of the implemented MAC and PHY.
The LLDP module is mainly for LLDP function configuration of the switch, including four
submenus: Basic Config, Device Info, Device Statistics and LLDP-MED.
16.1 Basic Config
LLDP is configured on the Global Config and Port Config pages.
16.1.1 Global Config
On this page you can configure the LLDP parameters of the device globally.
389
Choose the menu LLDP → Basic Config → Global Config to load the following page.
Figure 16-1 Global Configuration
Configuration Procedure:
Configure the global parameters here. Then click Apply to make the settings effective.
Entry Description:
Transmit Interval:
Indicates the interval at which LLDP frames are transmitted on
behalf of this LLDP agent.
Hold Multiplier:
This parameter is a multiplier on the Transmit Interval that
determines the actual TTL (Time To Live) value used
in an
LLDPDU. TTL = Hold Multiplier * Transmit Interval.
Reinit Delay: Specify the delay time before LLDP is re-
enabled on an
interface.
Notification
Interval:
Configure the interval of Trap message which will be sent from
the local device to the network management system.
16.1.2 Port Config
On this page you can configure all ports' LLDP parameters.
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Choose the menu LLDP → Basic Config → Port Config to load the following page.
Figure 16-2 Port Configuration
Configuration Procedure:
Select your desired port and configure the relevant parameters here. Then click Apply to make
the settings effective.
Entry Description:
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired entry for configuration. It is multi-optional.
Port:
Displays the port number to be configured.
Admin Status:
Configure the ports' LLDP state.
Notification Mode:
Enable or disable the ports' SNMP notification.
Included TLVs: Select TLVs to be included in outgoing LLDPDU.
By default, no
TLVs are included.
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16.2 Device Info
You can view the LLDP information of the local device and its neighbors on the Local Info and
Neighbor Info pages respectively.
16.2.1 Local Info
On this page you can view all ports' configuration and system information.
Choose the menu LLDP → Device Info → Local Info to load the following page.
Figure 16-3 Local Information
Configuration Procedure:
1) Choose Enable or Disable Auto Refresh according to your needs.
2) Select the desired port to view the information of the corresponding port under the Local
Info.
Entry Description:
Auto Refresh:
Enable/Disable the auto refresh function.
Refresh Rate:
Configure the auto refresh rate.
UNIT:
Select the unit ID of the desired member in the stack.
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Local Interface:
Displays the local port number.
Chassis ID Subtype
：
Indicates the basis for the chassis ID, and the default subtype
is MAC address.
Chassis ID
：
Indicates the specific identifier for the particular chassis in
local device.
Port ID Subtype
：
Indicates the basis for the port ID, and the de
fault subtype is
interface name.
Port ID：
Indicates the specific identifier for the port in local device.
TTL:
Indicates the number of seconds that the recipient LLDP
agent is to regard the information associated with this chassis
ID and port ID identifier to be valid.
Port Description：
Displays local port's description.
System Name：
Indicates local device's administratively assigned name.
System Description：
Displays local device's system description.
System Capabilities
Supported：
Displays the supported function of the local device.
System Capabilities
Enabled：
Displays the primary function of the local device.
Management
Address：
Displays the particular management address associated with
local device.
16.2.2 Neighbor Info
On this page you can view the information of the neighbors.
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Choose the menu LLDP → Device Info → Neighbor Info to load the following page.
Figure 16-4 Neighbor Information
Configuration Procedure:
1) Choose Enable or Disable Auto Refresh according to your needs.
2) Select the desired port to view the information of neighbor connected to the
corresponding port.
Entry Description:
Auto Refresh:
Enable/Disable the auto refresh function.
Refresh Rate:
Configure the auto refresh rate.
UNIT:
Select the unit ID of the desired member in the stack.
System Name:
Displays the system name of the neighbor device.
Chassis ID:
Displays the Chassis ID of the neighbor device.
System Description:
Displays the system description of the neighbor.
Neighbor Port:
Displays the port number of the neighbor linking to local port.
Information：
Click to display the detail information of the neighbor.
16.3 Device Statistics
You can view the LLDP statistics of local device through this feature.
Choose the menu LLDP → Device Statistics → Statistic Info to load the following page.
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Figure 16-5 Device Statistics
Configuration Procedure:
1) Choose Enable or Disable Auto Refresh according to your needs.
2) View Global Statistics and Neighbors Statistics in the corresponding table.
Entry Description:
Auto Refresh:
Enable/Disable the auto refresh function.
Refresh Rate:
Configure the auto refresh rate.
Last Update:
Display latest update time of the statistics.
Total Inserts:
Display the number of neighbors during latest update time.
Total Deletes:
Displays the number of neighbors deleted by local device.
Total Drops:
Displays the number of neighbors dropped by local device.
Total Ageouts:
Displays the number of overtime neighbors in local device.
UNIT:
Select the unit ID of the desired member in the stack.
Port:
Display local device's port number.
Transmit Total:
Displays the number of LLDPDUs sent by this port.
Receive Total:
Displays the number of LLDPDUs received by this port.
Discards:
Displays the number of LLDPDUs discarded by this port.
Errors:
Displays the number of error LLDPDUs received by this port.
Ageouts:
Displays the number of overtime neighbors linking to this port.
TLV Discards:
Displays the number of TLVs dropped by this port.
TLV Unknowns:
Displays the number of unknown TLVs received by this port.
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16.4 LLDP-MED
LLDP-MED is an extension of LLDP intended for managing endpoint devices such as Voice
over IP phones and network switches. The LLDP-MED TLVs advertise information such as
network policy and inventory management.
Elements
LLDP-MED Device: Refers to any device which implements this Standard.
LLDP-MED Device Type: LLDP-MED devices are comprised of two primary device types:
Network Connectivity Devices and Endpoint Devices.
Network Connectivity Device: Refers to an LLDP-MED Device that provides access to the
IEEE 802 based LAN infrastructure for LLDP-MED Endpoint Devices. Bridge is a Network
Connectivity Device.
Endpoint Device: Refers to an LLDP-MED Device at the network edge, providing some aspects
of IP communications service, based on IEEE 802 LAN technology. Endpoint Devices may be a
member of any of the Endpoint Device Classes. Endpoint Devices are composed of three
defined Classes: Class I, Class II and Class III.
Generic Endpoint Device (Class I): The most basic class of Endpoint Device.
Media Endpoint Device (Class II): The class of Endpoint Device that supports media stream
capabilities.
Communication Device Endpoint (Class III): The class of Endpoint Device that directly
supports end users of the IP communication system.
Network Policy TLV The Network Policy TLV allows both Network Connectivity
Devices and Endpoints to advertise VLAN configuration and
associated Layer 2 and Layer 3 attributes that apply for a
set of specific applications on that port.
Inventory TLV
The Inventory TLV set contains seven basic Inventory
management TLVs, that is, Hardware Revision TLV,
Firmware Revision TLV, Software Revision TLV, Serial
Number TLV, Manufacture
r Name TLV, Model Name TLV
and Asset ID TLV. If support for any of the TLVs in the
Inventory Management set is implemented, then support for
all Inventory Management TLVs shall be implemented.
LLDP-MED is configured on the Global Config, Port Config, Local Info and Neighbor Info
pages.
396
16.4.1 Global Config
On this page you can configure the LLDP-MED parameters of the device globally.
Choose the menu LLDP → LLDP-MED → Global Config to load the following page.
Figure 16-6 LLDP-MED Global Configuration
Configuration Procedure:
1) Configure the number of LLDP-MED frames which will be transmitted fast.
2) View Device Class of the device.
Entry Description:
Fast Start Count: When LLDP-MED fast start mechanism is activated, mu
ltiple
LLDP-
MED frames will be transmitted (the number of frames
equals this parameter).
LLDP-MED fast start mechanism will be activated w
hen
LLDP-MED status changes from disable to enable
. The device
will transmit a specified number of LLDP-MED frames fa
st then
the transmit interval will return to normal.
Device Class: LLDP-
MED devices are comprised of two primary device types:
Network Connectivity Devices and Endpoint Devices. In turn,
Endpoint Devices are composed of three defined Classes: Class
I, Class II and Class III. Bridge is a Network Connectivity Device.
397
16.4.2 Port Config
On this page you can configure all ports' LLDP-MED parameters.
Choose the menu LLDP → LLDP-MED → Port Config to load the following page.
Figure 16-7 LLDP-MED Port Configuration
Configuration Procedure:
1) Select your desired port and enable LLDP-MED. Then click Apply to make the settings
effective.
2) Click Detail to configure the included TLVs in outgoing LLDPDU on the following page.
Figure 16-8 Configure TLVs of LLDP-MED Port
Entry Description:
UNIT:
Select the unit ID of the desired member in the stack.
Select:
Select the desired port to configure.
398
LLDP-MED Status: Configure the port's LLDP-MED status:
• Enable: Enable the port's LLDP-MED status, and the port's
Admin Status will be changed to Tx&Rx.
•
Disable: Disable the port's LLDP-MED status.
Included TLVs: Select TLVs to be included in outgoing LLDPDU.
Click the Detail
button to display the included TLVs and select
the desired TLVs.
16.4.3 Local Info
On this page you can view all ports' LLDP-MED configuration.
Choose the menu LLDP → LLDP-MED → Local Info to load the following page.
Figure 16-9 LLDP-MED Local Information
Configuration Procedure:
1) Choose Enable or Disable Auto Refresh according to your needs.
2) Select the desired port to view the local information of the corresponding port under the
LLDP-MED Local Info.
399
Entry Description:
Auto Refresh:
Enable/Disable the auto refresh function.
Refresh Rate:
Specify the auto refresh rate.
Local Interface:
Enable/Disable the auto refresh function.
Device Type:
Specify the auto refresh rate.
Application Type:
Application Type indicates the primary function of the
applications defined for the network policy.
Unknown Policy
Flag:
Displays whether the local device will explicitly advertise the
policy required by the device but currently unknown.
VLAN tagged:
Indicates the VLAN type the specified application type is using,
'tagged' or 'untagged'.
Media Policy VLAN
ID:
Displays the application (eg. Voice VLAN) VLAN identifier (VID)
for the port.
Media Po
licy Layer
2 Priority:
Displays the Layer 2 priority to be used for the specified
application type.
Media Policy DSCP:
Displays the DSCP value to be used to provide Diffserv node
behavior for the specified application type as defined in IETF
RFC 2474.
Power Source:
Displays the power source being utilized by a PSE or PD device.
Power Priority:
Power Priority represents the priority of the PD type device to
the power being supplied by the PSE type device, or the power
priority associated with the PSE type
device's port that is
sourcing the power via MDI.
Available Power
Value:
Indicates the total power in watts required by a PD device from a
PSE device, or the total power a PSE device is capable of
sourcing over a maximum length cable based on its current
configuration.
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16.4.4 Neighbor Info
On this page you can get the LLDP-MED information of the neighbors.
Choose the menu LLDP → LLDP-MED → Neighbor Info to load the following page.
Figure 16-10 LLDP-MED Neighbor Information
Configuration Procedure:
1) Choose Enable or Disable Auto Refresh according to your needs.
2) Select the desired port to view the information of neighbor connected to the
corresponding port under the LLDP-MED Neighbor Info.
Entry Description:
Auto Refresh:
Enable/Disable the auto refresh function.
Refresh Rate:
Specify the auto refresh rate.
Unit:
Select the unit ID of the desired member in the stack.
Device Type:
Displays the device type of the neighbor.
Application Type:
Displays the application type of the neighbor. Application Type
indicates the primary function of the applications defined for the
network policy.
Local Data Format:
Displays the location identification of the neighbor.
Power Type: Displays the power type of the neighbor device, either Power
Sourcing Entity (PSE) or Powered Device (PD).
Information: Click the Information button to display the detailed information
of the corresponding neighbor.
Return to CONTENTS
401
Chapter 17 Maintenance
Maintenance module, assembling the commonly used system tools to manage the switch,
provides the convenient method to locate and solve the network problem.
1. System Monitor: Monitor the utilization status of the memory and the CPU of switch.
2. Log: View the configuration parameters of the switch and find out the errors via the
Logs.
3. Device Diagnose: Cable Test tests the connection status of the cable to locate and
diagnose the trouble spot of the network.
4. Network Diagnose: Test whether the destination device is reachable and detect the
route hops from the switch to the destination device.
17.1 System Monitor
System Monitor functions to display the utilization status of the memory and the CPU of switch
via the data graph. The CPU utilization rate and the memory utilization rate should fluctuate
stably around a specific value. If the CPU utilization rate or the memory utilization rate increases
markedly, please detect whether the network is being attacked.
The System Monitor function is implemented on the CPU Monitor and Memory Monitor
pages.
17.1.1 CPU Monitor
Choose the menu Maintenance → System Monitor → CPU Monitor to load the following page.
Figure17-1 CPU Monitor
402
UNIT:
Select the unit ID of the desired member in the stack.
Click the Monitor button to enable the switch to monitor and display its CPU utilization rate
every four seconds.
17.1.2 Memory Monitor
Choose the menu Maintenance → System Monitor → Memory Monitor to load the following
page.
Figure17-2 Memory Monitor
UNIT:
Select the unit ID of the desired member in the stack.
Click the Monitor button to enable the switch to monitor and display its Memory utilization rate
every four seconds.
17.2 Log
The Log system of switch can record, classify and manage the system information effectively,
providing powerful support for network administrator to monitor network operation and
diagnose malfunction.
The Logs of switch are classified into the following eight levels.
Severity
Level
Description
emergencies 0 The system is unusable.
alerts 1 Action must be taken immediately.
critical
2
Critical conditions
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Severity
Level
Description
errors
3
Error conditions
warnings 4 Warnings conditions
notifications 5 Normal but significant conditions
informational 6 Informational messages
debugging 7 Debug-level messages
Table 17-1 Log Level
The Log function is implemented on the Log Table, Local Log, Remote Log and Backup Log
pages.
17.2.1 Log Table
The switch supports logs output to two directions, namely, log buffer and log file. The
information in log buffer will be lost after the switch is rebooted or powered off whereas the
information in log file will be kept effective even the switch is rebooted or powered off. Log
Table displays the system log information in log buffer.
Choose the menu Maintenance → Log → Log Table to load the following page.
Figure17-3 Log Table
Configuration Procedure:
Select a module and a severity to view the corresponding log information.
Entry Description:
Index:
Displays the index of the log information.
404
Time:
Displays the time when the log event occurs. The log can get the
correct time after you configure on the System ->System Info->
System Time Web management page.
Module:
Displays the module which the log information belongs to. You can
select a module from the drop-
down list to display the
corresponding log information.
Severity:
Displays the severity level of the log information. You can select a
severity level to display the log information whose severity level
value is the same or smaller.
Content:
Displays the content of the log information.
Note:
1. There are 8 severity levels marked with value 0-7. The smaller value has the higher priority.
2. This page displays logs in the log buffer, and at most 1024 logs are displayed.
17.2.2 Local Log
Local Log is the log information saved in switch. By default, all system logs are saved in log
buffer and the function of saving logs to the log file in the flash is disabled. On this page, you
can set the output channel for logs.
Choose the menu Maintenance → Log → Local Log to load the following page.
Figure17-4 Local Log
Configuration Procedure:
1) Select your desired channel and configure the corresponding severity and status.
2) Click Apply to make the settings effective.
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Entry Description:
Channel
: Local log includes 2 channels: log buffer and log file.
Log buffer indicates the RAM for saving system log. The
channel is enabled by default. The information in the log buffer
is displayed on the Maintenance > Log> Log Table
page. It will
be lost when the switch is restarted.
Log File indicates the flash sector for saving system log. The
information in the log file will not be lost after the switch is
restarted and can be exported on the Maintenance >
Log>
Backup Log page.
Severity:
Specify the severity level of the log information output to each
channel. Only the log with the same or smaller severity level
value will be output.
Status:
Enable or disable the channel.
Sync
-Periodic Specify how freque
nt the log information would be
synchronized to the log file.
17.2.3 Remote Log
Remote log feature enables the switch to send system logs to the Log Server. Log Server is to
centralize the system logs from various devices for the administrator to monitor and manage
the whole network.
Choose the menu Maintenance → Log → Remote Log to load the following page.
Figure17-5 Log Host
406
Configuration Procedure:
Select an entry to enable the status, and then set the host IP address and severity. Click Apply to
make the settings effective.
Entry Description:
Admin Mode:
Enable or disable the log host. While enabled, syslog packets
will be sent to the hosts. While disabled, no syslog packets
will be sent to the hosts.
Index:
Displays the index of the log host. The switch supports 8 log
hosts.
Host IP:
Configure the IP for the log host.
UDP Port:
Displays the UDP port used for receiving/sending log
information. Here we use the standard port 514.
Severity:
Specify the severity level of the log information sent to each
log host. Only the log with the same or smaller severity level
value will be sent to the corresponding log host.
Status:
Displays the status of the corresponding log host.
Note:
The Log Server software is not provided. If necessary, please download it on the Internet.
17.2.4 Backup Log
Backup Log feature enables the system logs saved in the switch to be output as a file for
device diagnosis and statistics analysis. When a critical error results in the breakdown of the
system, you can export the logs to get some related important information about the error for
device diagnosis after the switch is restarted.
Choose the menu Maintenance → Log → Backup Log to load the following page.
Figure17-6 Backup Log
Configuration Procedure:
Click Backup Log to save the system log as a file on your computer. If the switch system breaks
down, you can check the file for troubleshooting.
407
Entry Description:
Backup Log:
Click the Backup Log button to save the log as a file to your
computer.
Note:
1. When a critical error results in the breakdown of the system, you can export the log file to
get some related important information about the error for device diagnosis after the
switch is restarted.
2. It will take a few minutes to back up the log file. Please wait without any operation.
17.3 Device Diagnose
This switch provides Cable Test and Loopback functions for device diagnose.
17.3.1 Cable Test
Cable Test functions to test the connection status of the cable connected to the switch, which
facilitates you to locate and diagnose the trouble spot of the network.
Choose the menu Maintenance → Device Diagnose → Cable Test to load the following page.
Figure17-7 Cable Test
Configuration Procedure:
1) In the Port section, select your desired port for the test.
2) In the Result section, click Apply and check the test results.
Entry Description:
Port:
Select the port for cable testing.
UNIT:
Select the unit ID of the desired member in the stack.
Status:
Test the connection status of the cable connected to the port.
408
Length:
If the connection status is
normal, here displays the length range of
the cable.
Error:
If the connection status is short, close or crosstalk, here displays
the length from the port to the trouble spot. The value makes sense
only when the cable is longer than 30m.
Note:
1. The interval between two cable tests for one port must be more than 3 seconds.
2. The result is more reasonable when the cable pair is in the open status.
3. The test result is just for your information.
4. If the port is 100Mbps and its connection status is normal, cable test cannot get the length
of the cable.
17.4 Network Diagnose
This switch provides Ping test and Tracert test functions for network Diagnose.
17.4.1 Ping
Ping test function, testing the connectivity between the switch and one node of the network,
facilitates you to test the network connectivity and reachability of the host so as to locate the
network malfunctions.
409
Choose the menu Maintenance → Network Diagnose → Ping to load the following page.
Figure17-8 Ping
Configuration Procedure:
1) In the Ping Config section, enter the IP address of the destination device for Ping test, set
Ping times, data size and interval according to your needs, and then click Ping to start the
test.
2) In the Ping Result section, check the test results.
Entry Description:
Destination IP:
Enter the IP address of the destination node for Ping test.
Ping Times:
Enter the amount of times to send test data during Ping testing. The
default value is recommended.
Data Size:
Enter the size of the sending
data during Ping testing. The default
value is recommended.
Interval:
Specify the interval to send ICMP request packets. The default
value is recommended.
17.4.2 Tracert
Tracert test function is used to test the connectivity of the gateways during its journey from the
source to destination of the test data. When malfunctions occur to the network, you can locate
trouble spot of the network with this tracert test.
410
Choose the menu Maintenance → Network Diagnose → Tracert to load the following page.
Figure17-9 Tracert
Configuration Procedure:
1) In the Tracert Config section, enter the IP address of the destination, set the max hop, and
then click Tracert to start the test.
2) In the Tracert Result section, check the test results.
Entry Description:
Destination IP:
Enter the IP address of the destination device.
Max Hop:
Specify the maximum number of the route hops the test data can
pass through.
Return to CONTENTS
411
Appendix A: Glossary
Access Control List (ACL)
ACLs can limit network traffic and restrict access to certain users or devices by checking each
packet for certain IP or MAC (i.e., Layer 2) information.
Boot Protocol (BOOTP)
BOOTP is used to provide bootup information for network devices, including IP address
information, the address of the TFTP server that contains the devices system files, and the
name of the boot file.
Class of Service (CoS)
CoS is supported by prioritizing packets based on the required level of service, and then
placing them in the appropriate output queue. Data is transmitted from the queues using
weighted round-robin service to enforce priority service and prevent blockage of lower-level
queues. Priority may be set according to the port default, the packet’s priority bit (in the VLAN
tag), TCP/UDP port number, or DSCP priority bit.
Differentiated Services Code Point (DSCP)
DSCP uses a six-bit tag to provide for up to 64 different forwarding behaviors. Based on
network policies, different kinds of traffic can be marked for different kinds of forwarding. The
DSCP bits are mapped to the Class of Service categories, and then into the output queues.
Domain Name Service (DNS)
A system used for translating host names for network nodes into IP addresses.
Dynamic Host Control Protocol (DHCP)
Provides a framework for passing configuration information to hosts on a TCP/IP network.
DHCP is based on the Bootstrap Protocol (BOOTP), adding the capability of automatic
allocation of reusable network addresses and additional configuration options.
Extensible Authentication Protocol over LAN (EAPOL)
EAPOL is a client authentication protocol used by this switch to verify the network access
rights for any device that is plugged into the switch. A user name and password is requested by
the switch, and then passed to an authentication server (e.g., RADIUS) for verification. EAPOL is
implemented as part of the IEEE 802.1X Port Authentication standard.
GARP VLAN Registration Protocol (GVRP)
Defines a way for switches to exchange VLAN information in order to register necessary VLAN
members on ports along the Spanning Tree so that VLANs defined in each switch can work
automatically over a Spanning Tree network.
Generic Attribute Registration Protocol (GARP)
The GARP provides a generic attribute dissemination capability that is used by participants in
GARP Applications (GARP Participants) to register and de-register attribute values with other
GARP Participants within a Bridged LAN. The definition of the attribute types, the values that
they can carry, and the semantics that are associated with those values when registered, are
specific to the operation of the GARP Application concerned.
412
Generic Multicast Registration Protocol (GMRP)
GMRP allows network devices to register end stations with multicast groups. GMRP requires
that any participating network devices or end stations comply with the IEEE 802.1p standard.
Group Attribute Registration Protocol (GARP)
See Generic Attribute Registration Protocol.
IEEE 802.1d
Specifies a general method for the operation of MAC bridges, including the Spanning Tree
Protocol.
IEEE 802.1q
VLAN Tagging—Defines Ethernet frame tags which carry VLAN information. It allows switches
to assign endstations to different virtual LANs, and defines a standard way for VLANs to
communicate across switched networks.
IEEE 802.1p
An IEEE standard for providing quality of service (QoS) in Ethernet networks. The standard uses
packet tags that define up to eight traffic classes and allows switches to transmit packets
based on the tagged priority value.
IEEE 802.1X
Port Authentication controls access to the switch ports by requiring users to first enter a user
ID and password for authentication.
IEEE 802.3ac
Defines frame extensions for VLAN tagging.
IEEE 802.3x
Defines Ethernet frame start/stop requests and timers used for flow control on full-duplex links.
(Now incorporated in IEEE 802.3-2002)
Internet Group Management Protocol (IGMP)
A protocol through which hosts can register with their local router for multicast services. If
there is more than one multicast switch/router on a given subnetwork, one of the devices acts
as the “querier” and assumes responsibility for keeping track of group membership.
IGMP Snooping
Listening to IGMP Query and IGMP Report packets transferred between IP Multicast Routers
and IP Multicast host groups to identify IP Multicast group members.
IGMP Query
On each subnetwork, one IGMP-capable device will act as the querier — that is, the device that
asks all hosts to report on the IP multicast groups they wish to join or to which they already
belong. The elected querier will be the device with the lowest IP address in the subnetwork.
IP Multicast Filtering
It is a feature to allow or deny the Client to add the specified multicast group.
413
Multicast Switching
A process whereby the switch filters incoming multicast frames for services for which no
attached host has registered, or forwards them to all ports contained within the designated
multicast group.
Layer 2
Data Link layer in the ISO 7-Layer Data Communications Protocol. This is related directly to the
hardware interface for network devices and passes on traffic based on MAC addresses.
Link Aggregation
See Port Trunk.
Link Aggregation Control Protocol (LACP)
Allows ports to automatically negotiate a trunked link with LACP-configured ports on another
device.
Management Information Base (MIB)
An acronym for Management Information Base. It is a set of database objects that contains
information about a specific device.
MD5 Message-Digest Algorithm
An algorithm that is used to create digital signatures. It is intended for use with 32 bit machines
and is safer than the MD4 algorithm, which has been broken. MD5 is a one-way hash function,
meaning that it takes a message and converts it into a fixed string of digits, also called a
message digest.
Network Time Protocol (NTP)
NTP provides the mechanisms to synchronize time across the network. The time servers
operate in a hierarchical-master-member configuration in order to synchronize local clocks
within the subnet and to national time standards via wire or radio.
Port Authentication
See IEEE 802.1X.
Port Mirroring
A method whereby data on a target port is mirrored to a monitor port for troubleshooting with a
logic analyzer or RMON probe. This allows data on the target port to be studied unobstructively.
Port Trunk
Defines a network link aggregation and trunking method which specifies how to create a single
high-speed logical link that combines several lower-speed physical links.
Remote Authentication Dial-in User Service (RADIUS)
RADIUS is a logon authentication protocol that uses software running on a central server to
control access to RADIUS-compliant devices on the network.
Remote Monitoring (RMON)
RMON provides comprehensive network monitoring capabilities. It eliminates the polling
required in standard SNMP, and can set alarms on a variety of traffic conditions, including
specific error types.
414
Rapid Spanning Tree Protocol (RSTP)
RSTP reduces the convergence time for network topology changes to about 10% of that
required by the older IEEE 802.1D STP standard.
Secure Shell (SSH)
A secure replacement for remote access functions, including Telnet. SSH can authenticate
users with a cryptographic key, and encrypt data connections between management clients
and the switch.
Simple Network Management Protocol (SNMP)
The application protocol in the Internet suite of protocols which offers network management
services.
Simple Network Time Protocol (SNTP)
SNTP allows a device to set its internal clock based on periodic updates from a Network Time
Protocol (NTP) server. Updates can be requested from a specific NTP server, or can be
received via broadcasts sent by NTP servers.
Spanning Tree Algorithm (STA)
A technology that checks your network for any loops. A loop can often occur in complicated or
backup linked network systems. Spanning Tree detects and directs data along the shortest
available path, maximizing the performance and efficiency of the network.
Telnet
Defines a remote communication facility for interfacing to a terminal device over TCP/IP.
Transmission Control Protocol/Internet Protocol (TCP/IP)
Protocol suite that includes TCP as the primary transport protocol, and IP as the network layer
protocol.
Trivial File Transfer Protocol (TFTP)
A TCP/IP protocol commonly used for software downloads.
User Datagram Protocol (UDP)
UDP provides a datagram mode for packet-switched communications. It uses IP as the
underlying transport mechanism to provide access to IP-like services. UDP packets are
delivered just like IP packets – connection-less datagrams that may be discarded before
reaching their targets. UDP is useful when TCP would be too complex, too slow, or just
unnecessary.
Virtual LAN (VLAN)
A Virtual LAN is a collection of network nodes that share the same collision domain regardless
of their physical location or connection point in the network. A VLAN serves as a logical
workgroup with no physical barriers, and allows users to share information and resources as
though located on the same LAN.
Return to CONTENTS
415
COPYRIGHT & TRADEMARKS
Specifications are subject to change without notice. is a registered trademark of
TP-Link Technologies Co., Ltd. Other brands and product names are trademarks or registered
trademarks of their respective holders.
No part of the specifications may be reproduced in any form or by any means or used to make
any derivative such as translation, transformation, or adaptation without permission from
TP-Link Technologies Co., Ltd. Copyright © 2019 TP-Link Technologies Co., Ltd. All rights
reserved.
http://www.tp-link.com
FCC STATEMENT
Product Name: JetStream L3 Stackable Managed Switch
Model Number: T3700G-28TQ/T3700G-52TQ
Responsible party:
TP-Link USA Corporation, d/b/a TP-Link North America, Inc.
Address: 145 South State College Blvd. Suite 400, Brea, CA 92821
Website: http://www.tp-link.com/us/
Tel: +1 626 333 0234
Fax: +1 909 527 6803
E-mail: sales.usa@tp-link.com
This equipment has been tested and found to comply with the limits for a Class A digital device,
pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable
protection against harmful interference when the equipment is operated in a commercial
environment. This equipment generates, uses, and can radiate radio frequency energy and, if
not installed and used in accordance with the instruction manual, may cause harmful
interference to radio communications. Operation of this equipment in a residential area is likely
to cause harmful interference in which case the user will be required to correct the interference
at his own expense.
This device complies with part 15 of the FCC Rules. Operation is subject to the following two
conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received, including interference that may cause
undesired operation.
Any changes or modifications not expressly approved by the party responsible for compliance
could void the user’s authority to operate the equipment.
416
We, TP-Link USA Corporation, has determined that the equipment shown as above has been
shown to comply with the applicable technical standards, FCC part 15. There is no unauthorized
change is made in the equipment and the equipment is properly maintained and operated.
Issue Date: 2018.11.12
CE Mark Warning
This is a class A product. In a domestic environment, this product may cause radio interference,
in which case the user may be required to take adequate measures.
EU declaration of conformity
TP-Link hereby declares that the device is in compliance with the essential requirements and
other relevant provisions of directives 2014/30/EU, 2014/35/EU, 2009/125/EC and
2011/65/EU.
The original EU declaration of conformity may be found at http://www.tp-link.com/en/ce
Industry Canada Statement
CAN ICES-3 (A)/NMB-3(A)
Продукт сертифіковано згідно с правилами системи УкрСЕПРО на відповідність вимогам
нормативних документів та вимогам, що передбачені чинними законодавчими актами
України.
Safety Information
Keep the device away from water, fire, humidity or hot environments.
Do not attempt to disassemble, repair, or modify the device.
Do not use damaged charger or USB cable to charge the device.
Do not use any other chargers than those recommended.
Place the device with its bottom surface downward.
417
Please read and follow the above safety information when operating the device. We cannot
guarantee that no accidents or damage will occur due to improper use of the device. Please
use this product with care and operate at your own risk.
安全諮詢及注意事項
請使用原裝電源供應器或只能按照本產品注明的電源類型使用本產品。
清潔本產品之前請先拔掉電源線。請勿使用液體、噴霧清潔劑或濕布進行清潔。
注意防潮，請勿將水或其他液體潑灑到本產品上。
插槽與開口供通風使用，以確保本產品的操作可靠並防止過熱，請勿堵塞或覆蓋開口。
請勿將本產品置放於靠近熱源的地方。除非有正常的通風，否則不可放在密閉位置中。
請不要私自打開機殼，不要嘗試自行維修本產品，請由授權的專業人士進行此項工作。
此為甲類資訊技術設備，于居住環境中使用時，可能會造成射頻擾動，在此種情況下，使用者會被
要求採取某些適當的對策。
限用物質含有情況標示聲明書
產品元件名稱
限用物質及其化學符號
鉛
Pb
鎘
Cd
汞
Hg
六價鉻
CrVI
多溴聯苯
PBB
多溴二苯醚
PBDE
PCB ○ ○ ○ ○ ○ ○
外殼 ○ ○ ○ ○ ○ ○
電源供應板 − ○ ○ ○ ○ ○
備考
1. "超出 0.1 wt %" 及 "超出 0.01 wt %"
系指限用物質之百分比含量超出百分比含量基準
值。
備考
2. "○"系指該項限用物質之百分比含量未超出百分比含量基準值。
備考
3. " − " 系指該項限用物質為排除項目。
この装置は、クラス A情報技術装置です。この装置を家庭環境で使用すると電波妨害を引き起こ
すことがあります。この場合には使用者が適切な対策を講ずるよう要求されることがあります。
VCCI-A
418
Explanation of the symbols on the product label
Symbol
Explanation
AC voltage
Indoor use only
RECYCLING
This product bears the selective sorting symbol for Waste electrical
and electronic equipment (WEEE). This means that this product must
be handled pursuant to European directive 2012/19/EU in order to be
recycled or dismantled to minimize its impact on the environment.
User has the choice to give his product to a competent recycling
organization or to the retailer when he buys a new electrical or
electronic equipment.
419