TP-LINK JetStream L2 SG3210, SG3216, SG3424 network switch User Guide
Below you will find brief information for network switch JetStream L2 SG3216, network switch JetStream L2 SG3210, network switch JetStream L2 SG3424. These network switches are designed for workgroups and departments, providing wire-speed performance and full set of layer 2 management features. They provide a variety of service features and multiple powerful functions with high security. The EIA-standardized framework and smart configuration capacity can provide flexible solutions for a variable scale of networks. These switches integrate multiple functions with excellent performance, and are friendly to manage, which can fully meet the need of the users demanding higher networking performance.
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TL-SG3210/TL-SG3216/TL-SG3424
JetStream L2 Managed Switch
REV2.0.0
1910010918
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 © 2013 TP-LINK TECHNOLOGIES CO., LTD. All rights reserved. http://www.tp-link.com
FCC STATEMENT
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.
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.
Продукт сертифіковано згідно с правилами системи УкрСЕПРО на відповідність вимогам нормативних документів та вимогам , що передбачені чинними законодавчими актами
України .
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Safety Information
When product has power button, the power button is one of the way to shut off the product;
When there is no power button, the only way to completely shut off power is to disconnect the product or the power adapter from the power source.
Don’t disassemble the product, or make repairs yourself. You run the risk of electric shock and voiding the limited warranty. If you need service, please contact us.
Avoid water and wet locations.
This product can be used in the following countries:
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ES FI FR GB GR HU IE IT
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RU SE SK TR UA
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CONTENTS
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Package Contents
The following items should be found in your box:
One JetStream L2 Managed Switch
One power cord
One console cable
Two mounting brackets and other fittings
Installation
Resource CD for TL-SG3210/TL-SG3216/TL-SG3424 switch, including:
This 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.
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Chapter 1 About This Guide
This User Guide contains information for setup and management of TL-SG3210/TL-SG3216/
TL-SG3424 JetStream L2 Managed 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
In this Guide the following conventions are used:
The switch or device mentioned in this Guide stands for JetStream L2 Managed Switch without any explanation.
Tips:
The TL-SG3210/TL-SG3216/TL-SG3424 switchs are sharing this User Guide. For simplicity, we will take TL-SG3216 for example throughout this Guide. They just differ in the number of LED indicators and ports and all fi gures in this guide are of TL-SG3216.
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.
1.3 Overview of This Guide
Chapter
Chapter 1 About This Guide
Chapter 2 Introduction
Introduction
Introduces the guide structure and conventions.
Introduces the features, application and appearance of TL-SG3216 switch.
Chapter 3 Login to the Switch Introduces how to log on to the Web management page.
2
Chapter
Chapter 4 System
Chapter 5 Switching
Chapter 6 VLAN
Chapter 7 Spanning Tree
Chapter 8 Multicast
Introduction
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 log on to the Web management page with a certain access level.
System Tools: Manage the configuration file of the switch.
Access Security: Provide different security measures for the login to enhance the configuration management security.
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.
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.
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.
This module is used to configure spanning tree function of the switch. Here mainly introduces:
STP Config: Configure 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.
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.
Multicast IP: Configure multicast IP table.
Multicast Filter: Configure multicast filter feature to restrict users ordering multicast programs.
Packet Statistics: View the multicast data traffic on each port of the switch, which facilitates you to monitor the IGMP messages in the network.
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Chapter
Chapter 9 QoS
Chapter 10 ACL
Chapter 11 Network Security
Chapter 12 SNMP
Chapter 13 Cluster
Introduction
This module is used to configure QoS function to provide different quality of service for various network applications and requirements. Here mainly introduces:
DiffServ: Configure priorities, port priority, 802.1P priority and
DSCP priority.
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 so as to ensure the transmission priority of voice data stream and voice quality.
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: ACL rules.
Policy Config: Configure operation policies.
Policy Binding: Bind the policy to a port/VLAN to take its effect on a specific port/VLAN.
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.
ARP Inspection: Configure ARP inspection feature to prevent the network from ARP attacks.
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.
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.
This module is used to configure cluster function to central manage the scattered devices in the network. Here mainly introduces:
NDP: Configure NDP function to get the information of the directly connected neighbor devices.
NTDP: Configure NTDP function for the commander switch to collect NDP information.
Cluster: Configure cluster function to establish and maintain cluster.
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Chapter
Chapter 14 Maintenance
Introduction
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 configuration parameters on the switch.
Device Diagnostics: Test the connection status of the cable connected to the switch, test if the port of the switch and the connected device are available.
Network Diagnostics: Test if the destination is reachable and the account of router hops from the switch to the destination.
Appendix A Specifications Lists the hardware specifications of the switch.
Appendix B Configure the PCs Introduces how to configure the PCs.
Introduces how to load firmware of the switch via FTP function. Appendix C Load Software
Using FTP
Appendix D 802.1X Client
Software
Appendix E Glossary
Introduces how to use 802.1X Client Software provided for authentication.
Lists the glossary used in this manual.
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Chapter 2 Introduction
Thanks for choosing the TL-SG3210/TL-SG3216/TL-SG3424 JetStream L2 Managed Switch!
2.1 Overview of the Switch
Designed for workgroups and departments, TL-SG3210/TL-SG3216/TL-SG3424 from TP-LINK provides wire-speed performance and full set of layer 2 management features. It provides a variety of service features and multiple powerful functions with high security.
The EIA-standardized framework and smart configuration capacity can provide flexible solutions for a variable scale of networks. ACL, 802.1x and Dynamic ARP Inspection provide robust security strategy. QoS and IGMP snooping/filtering optimize voice and video application. Link aggregation
(LACP) increases aggregated bandwidth, optimizing the transport of business critical data. SNMP,
RMON, WEB/CLI/Telnet Log-in bring abundant management policies. TL-SG3210/TL-SG3216/
TL-SG3424 switch integrates multiple functions with excellent performance, and is friendly to manage, which can fully meet the need of the users demanding higher networking performance.
2.2 Main Features
Resiliency and Availability
+ Link aggregation (LACP) increases aggregated bandwidth, optimizing the transport of business critical data.
+ IEEE 802.1s Multiple Spanning Tree provides high link availability in multiple VLAN environments.
+ Multicast snooping automatically prevents flooding of IP multicast traffic.
+ Root Guard protects root bridge from malicious attack or configuration mistakes
Layer 2 Switching
+ GVRP (GARP VLAN Registration Protocol) allows automatic learning and dynamic assignment of VLANs.
+ Supports up to 4K VLANs simultaneously (out of 4K VLAN IDs).
Quality of Service
+ Supports L2/L3 granular CoS with 4 priority queues per port.
+ Rate limiting confines the traffic flow accurately according to the preset value.
Security
+ Supports multiple industry standard user authentication methods such as 802.1x, RADIUS.
+ Dynamic ARP Inspection blocks ARP packets from unauthorized hosts, preventing man-in-the-middle attacks.
+ L2/L3/L4 Access Control Lists restrict untrusted access to the protected resource.
+ Provides SSHv1/v2, SSL 2.0/3.0 and TLS v1 for access encryption.
Manageability
+ IP Clustering provides high scalability and easy Single-IP-Management.
+ Supports Telnet, CLI, SNMP v1/v2c/v3, RMON and web access.
+ Port Mirroring enables monitoring selected ingress/egress traffic.
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2.3 Appearance Description
2.3.1 Front Panel
The front panel of TL-SG3210 is shown as the following figure.
Figure 2-1 Front Panel of TL-SG3210
The front panel of TL-SG3216 is shown as the following figure.
Figure 2-1 Front Panel of TL-SG3216
The front panel of TL-SG3424 is shown as the following figure.
Figure 2-1 Front Panel of TL-SG3424
The following parts are located on the front panel of the switch:
10/100/1000Mbps Ports:
Designed to connect to the device with a bandwidth of 10Mbps,
100Mbps or 1000Mbps. Each has a corresponding 1000Mbps LED.
SFP Ports:
Designed to install the SFP module. TL-SG3216/TL-SG3424 switch features some
SFP transceiver slots that are shared with the associated RJ45 ports. The associated two ports are referred to as “Combo” ports, which means they cannot be used simultaneously, otherwise only SFP ports work. TL-SG3210 features two individual SFP ports.
Note:
For TL-SG3216/TL-SG3424 switch, when using the SFP port with a 100M module or a gigabit module, you need to configure its corresponding
Speed and Duplex
mode on
Switching → Port → Port Config
page. For 100M module, please select
100MFD
while select
1000MFD
for gigabit module. By default, the
Speed and Duplex
mode of SFP port is 1000MFD.
For TL-SG3210, it only supports
1000MFD
mode.
Console Port:
Designed to connect with the serial port of a computer or terminal for monitoring and configuring the switch.
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LEDs
Name
Power
System
1000Mbps
Link/Act
Status
On
Flashing
Off
On
Flashing
Off
On
Off
On
Flashing
Off
Indication
Power is on.
Power supply is abnormal.
Power is off or power supply is abnormal.
The switch is working abnormally.
The switch is working normally.
The switch is working abnormally.
A 1000Mbps device is connected to the corresponding port.
A 10/100Mbps device or no device is connected to the corresponding port.
A device is connected to the corresponding port, but not activity.
Data is being transmitted or received.
No device is connected to the corresponding port.
2.3.2 Rear Panel
The rear panel of the switch features a power socket and a Grounding Terminal (marked with ), here we take TL-SG3216 for example.
Figure 2-2 Rear Panel
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.
AC Power Socket:
Connect the female connector of the power cord here, and the male connector to the AC power outlet. Please make sure the voltage of the power supply meets the requirement of the input voltage (100-240V~ 50/60Hz 0.6A).
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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. For the detailed instructions as to how to do this, please refer to Appendix B
.
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.
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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.
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Chapter 4 System
The System module is mainly for system configuration of the switch, including four submenus:
System Info
,
User Management, System Tools
and
Access Security
.
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
and
System IP
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 16 10/100/1000Mbps RJ45 ports and 2 SFP ports of the switch. Ports 1-14,15T-16T are 10/100/1000Mbps ports and ports 15T-16T are Combo ports with SFP ports labeled as 15F-16F.
Choose the menu
System → System Info → System Summary
to load the following page.
Figure 4-1 System Summary
The following entries are displayed on this screen:
Port Status
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.
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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 at the speed of 100Mbps.
When the cursor moves on the port, the detailed information of the port will be displayed.
Figure 4-2 Port Information
Port Info
Port:
Type:
Speed:
Status:
Displays the port number of the switch.
Displays the type of the port.
Displays the maximum transmission rate of the port.
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. The following figure 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 bandwidth utilization of receiving packets on this port.
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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.
Figure 4-4 Device Description
The following entries are displayed on this screen:
Device Description
Device Name:
Device Location:
System Contact:
Enter the name of the switch.
Enter the location of the switch.
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 time from NTP server automatically if it has connected to a 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
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The following entries are displayed on this screen:
Time Info
Current System
Date:
Current Time
Source:
Time Config
Displays the current date and time of the switch.
Displays the current time Source of the switch.
Manual:
Get time from NTP
Server:
When this option is selected, you can set the date and time manually.
When this option is selected, you can configure the time zone and the IP Address for the NTP server. The switch will get time from
NTP server automatically if it has connected to a NTP server.
Time Zone: Select your local time.
Primary/Secondary NTP Server: Enter the IP Address for the
NTP server.
Update Rate: Specify the rate fetching 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.
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Figure 4-6 Daylight Saving Time
The following entries are displayed on this screen:
DST Config
DST Status:
Predefined Mode:
Recurring Mode:
Date Mode:
Enable or disable the DST.
Select a predefined DST configuration.
USA: Second Sunday in March, 02:00 ~ First Sunday in
November, 02:00.
Australia: First Sunday in October, 02:00 ~ First Sunday in
April, 03:00.
Europe: Last Sunday in March, 01:00 ~ Last Sunday in
October, 01:00.
New Zealand: Last Sunday in September, 02:00 ~ First
Sunday in April, 03:00.
Specify the 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.
Specify the DST configuration in Date 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.
Note:
1. When the DST is disabled, the predefined mode, recurring mode and date mode cannot be configured.
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2. When the DST is enabled, the default daylight saving time is of Europe in predefined mode.
4.1.5 System IP
Each device in the network possesses a unique IP Address. You can log on to the Web management page to operate the switch using this IP Address. The switch supports three modes to obtain an IP address: Static IP, DHCP and BOOTP. The IP address obtained using a new mode will replace the original IP address. On this page you can configure the system IP of the switch.
Choose the menu
System → System Info → System IP
to load the following page.
Figure 4-7 System IP
The following entries are displayed on this screen:
IP Config
MAC Address:
IP Address Mode:
IP Address:
Subnet Mask:
Default Gateway:
Displays MAC Address of the switch.
Select the mode to obtain IP Address for the switch.
Static IP: When this option is selected, you should enter IP
Address, Subnet Mask and Default Gateway manually.
DHCP: When this option is selected, the switch will obtain network parameters from the DHCP Server.
BOOTP: When this option is selected, the switch will obtain network parameters from the BOOTP Server.
Enter the system IP of the switch. The default system IP is
192.168.0.1 and you can change it appropriate to your needs.
Enter the subnet mask of the switch.
Enter the default gateway of the switch.
Note:
1. Changing the IP address to a different IP segment will interrupt the network communication, so please keep the new IP address in the same IP segment with the local network.
2. The switch only possesses an IP address. The IP address configured will replace the original
IP address.
3. If the switch gets the IP address from DHCP server, you can see the configuration of the switch in the DHCP server; if DHCP option is selected but no DHCP server exists in the network, a few minutes later, the switch will restore the setting to the default.
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4. If DHCP or BOOTP option is selected, the switch will get network parameters dynamically from the Internet, which means that its IP address, subnet mask and default gateway can not be configured.
5. By default, the IP address is 192.168.0.1.
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 4-8 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.
Choose the menu
System → User Management → User Config
to load the following page.
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Figure 4-9 User Config
The following entries are displayed on this screen:
User Info
User Name:
Access Level:
User Status:
Password:
Confirm Password:
Create a name for users’ login.
Select the access level to login.
Admin: Admin can edit, modify and view all the settings of different functions.
Guest: Guest only can view the settings without the right to edit and modify.
Select Enable/Disable the user configuration.
Type a password for users’ login.
Retype the password.
User Table
Select:
Select the desired entry to delete the corresponding user information. It is multi-optional The current user information can’t be deleted.
User ID, Name,
Access Level and status:
Operation:
Displays the current user ID, user name, access level and user status.
Click the
Edit
button of the desired entry, and you can edit the corresponding user information. After modifying the settings, please click the
Modify
button to make the modification effective.
Access level and user status of the current user information can’t be modified.
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4.3 System Tools
The System Tools function, allowing you to manage the configuration file of the switch, can be implemented on
Config Restore
,
Config Backup
,
Firmware Upgrade
,
System Reboot
and
System Reset
pages.
4.3.1 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 4-10 Config Restore
The following entries are displayed on this screen:
Config Restore
Restore Config:
Click the
Restore Config
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 being restored, the current settings of the switch will be lost. Wrong uploaded configuration file may cause the switch unmanaged.
4.3.2 Config Backup
On this page you can download the current configuration 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.
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Figure 4-11 Config Backup
The following entries are displayed on this screen:
Config Backup
Backup Config:
Click the
Backup Config
button to save the current configuration as a file to your computer. You are suggested to take this measure before upgrading.
Note:
It will take a few minutes to backup the configuration. Please wait without any operation.
4.3.3 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 4-12 Firmware Upgrade
Note:
1. Don’t interrupt the upgrade.
2. Please select the proper software version matching with your hardware to upgrade.
3. To avoid damage, please don't turn off the device while upgrading.
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4. After upgrading, the device will reboot automatically.
5. You are suggested to backup the configuration before upgrading.
4.3.4 System Reboot
On this page you can reboot the switch and return to the login page. Please save the current configuration before rebooting to avoid losing the configuration unsaved
Choose the menu
System → System Tools → System Reboot
to load the following page.
Figure 4-13 System Reboot
Note:
To avoid damage, please don't turn off the device while rebooting.
4.3.5 System Reset
On this page you can reset the switch 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 4-14 System Reset
Note:
After the system is reset, the switch will be reset to the default and all the settings will be cleared.
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
,
SSL Config
and
SSH 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
.
Choose the menu
System → Access Security → Access Control
to load the following page.
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Figure 4-15 Access Control
The following entries are displayed on this screen:
Access Control Config
Control Mode:
IP Address&Mask
MAC Address:
Port:
Select the control mode for users to log on to the Web management page.
IP-based: Select this option to limit the IP-range of the users for login.
MAC-based: Select this option to limit the MAC Address of the users for login.
Port-based: Select this option to limit the ports for login.
These fields can be available for configuration only when IP-based mode is selected. Only the users within the IP-range you set here is allowed for login.
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 login.
The field can be available for configuration only when Port-based mode is selected. Only the users connected to these ports you set here is allowed for login.
Session Config
Session Timeout:
If you do nothing with the Web management page within the timeout time, the system will log out automatically. If you want to reconfigure, please login again.
Access User Number
22
Number Control
；
Admin Number:
Guest Number:
Select Enable/Disable the Number Control function.
Enter the maximum number of the users logging on to the Web management page as Admin.
Enter the maximum number of the users logging on to the Web management page as Guest.
4.4.2 SSL 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 trusted certificate authority” or “Certificate Errors”. Please add this certificate to trusted certificates or continue to this website.
On this page you can configure the SSL function.
Choose the menu
System → Access Security → SSL Config
to load the following page.
Figure 4-16 SSL Config
23
The following entries are displayed on this screen:
Global Config
Select Enable/Disable the SSL function on the switch.
SSL:
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 SSL Key to download to the switch. The key must be BASE64 encoded.
Note:
1. The SSL certificate and key downloaded must match each other; otherwise the HTTPS connection will not work.
2. The SSL certificate and key downloaded will not take effect until the switch is rebooted.
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.
4.4.3 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.
Choose the menu
System → Access Security → SSH Config
to load the following page.
24
Figure 4-17 SSH Config
The following entries are displayed on this screen:
Global Config
SSH:
Protocol V1:
Protocol V2:
Idle Timeout:
Max Connect:
Select Enable/Disable SSH function.
Select Enable/Disable SSH V1 to be the supported protocol.
Select Enable/Disable SSH V2 to be the supported protocol.
Specify the idle timeout time. The system will automatically release the connection when the time is up. The default time is
500 seconds.
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.
Key Download
Key Type:
Key File:
Download:
Select the type of SSH Key to download. The switch supports three types: SSH-1 RSA, SSH-2 RSA and SSH-2 DSA.
Select the desired key file to download.
Click the
Download
button to download the desired key file to the switch.
Note:
1. Please ensure the key length of the downloaded file is in the range of 256 to 3072 bits.
2. After the Key File is downloaded, the user’s original key of the same type will be replaced.
The wrong uploaded file will result in the SSH access to the switch via Password authentication.
25
Application Example 1 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.
2. Click the 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.
Application Example 2 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. Select the key type and key length, and generate SSH key.
26
Note:
1. The key length is in the range of 256 to 3072 bits.
2. During the key generation, randomly moving the mouse quickly can accelerate the key generation.
2. After the key is successfully generated, please save the public key and private key to the computer.
27
3. On the Web management page of the switch, download the public key file saved in the computer to the switch.
Note:
1. The key type should accord with the type of the key file.
2. The SSH key downloading can not be interrupted.
4. Download the private key file to SSH client software.
5. After the public key and private key are downloaded, please log on to the interface of PuTTY and enter the IP address for login.
28
After successful authentication, please enter the login user name. If you log on to the switch without entering password, it indicates that the key has been successfully downloaded.
29
Chapter 5 Switching
Switching module is used to configure the basic functions of the switch, including four submenus:
Port
,
LAG
,
Traffic Monitor
and
MAC Address
.
5.1 Port
The Port function, allowing you to configure the basic features for the port, is implemented on the
Port Config
,
Port Mirror
,
Port Security
,
Port Isolation
and
Loopback detection
pages.
5.1.1 Port Config
On this page, you can configure the basic parameters for the ports. When the port is disabled, the packets on the port will be discarded. Disabling the port which is vacant for a long time can reduce the power consumption effectively. And you can enable the port when it is in need.
The parameters will affect the working mode of the port, please set the parameters appropriate to your needs.
Choose the menu
Switching → Port → Port Config
to load the following page.
Figure 5-1 Port Config
Here you can view and configure the port parameters.
Port Config
Port Select:
Select:
Port:
Description:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for configuration. It is multi-optional.
Displays the port number.
Give a description to the port for identification.
30
Status:
Speed and Duplex:
Flow Control:
Allows you to Enable/Disable the port. When Enable is selected, the port can forward the packets normally.
Select the Speed and Duplex mode for the port. The device connected to the switch should be in the same Speed and
Duplex mode with the switch. When “Auto” is selected, the
Speed and Duplex mode will be determined by auto-negotiation. For the SFP port, this switch does not support auto-negotiation.
Allows you to Enable/Disable the Flow Control feature. When
Flow Control is enabled, the switch can synchronize the speed with its peer to avoid the packet loss caused by congestion.
Displays the LAG number which the port belongs to.
LAG:
Note:
1. The switch can not 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. For TL-SG3216/TL-SG3424, when using the SFP port with a 100M module or a gigabit module, you need to configure its corresponding
Speed and Duplex
mode. For 100M module, please select
100MFD
while select
1000MFD
for gigabit module. By default, the
Speed and Duplex
mode of SFP port is 1000MFD. For TL-SG3210, it only supports
1000MFD
mode.
5.1.2 Port Mirror
Port Mirror, the packets obtaining technology, functions to forward copies of packets from one/multiple ports (mirrored port) to a specific port (mirroring port). Usually, the mirroring port is connected to a data diagnose device, which is used to analyze the mirrored packets for monitoring and troubleshooting the network.
Choose the menu
Switching → Port → Port Mirror
to load the following page.
Figure 5-2 Mirror Group LIst
The following entries are displayed on this screen.
31
Mirror Group List
Group:
Mirroring:
Mode:
Mirrored Port:
Operation:
Displays the mirror group number.
Displays the mirroring port number.
Displays the mirror mode, the value will be "Ingress" or "Egress".
Displays the mirrored ports.
Click
Edit
to configure the mirror group.
Click
Edit
to display the following figure.
Figure 5-3 Port Mirror Config
The following entries are displayed on this screen.
Mirror Group
Select the mirror group number you want to configure.
Number:
Mirroring Port
Mirroring Port:
Mirrored Port
Select the mirroring port number.
32
Port Select:
Select:
Port:
Ingress:
Egress:
LAG:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port as a mirrored port. It is multi-optional.
Displays the port number.
Select Enable/Disable the Ingress feature. When the Ingress is enabled, the incoming packets received by the mirrored port will be copied to the mirroring port.
Select Enable/Disable the Egress feature. When the Egress is enabled, the outgoing packets sent by the mirrored port will be copied to the mirroring port.
Displays the LAG number which the port belongs to. The LAG member can not be selected as the mirrored port or mirroring port.
Note:
1. The LAG member can not be selected as the mirrored port or mirroring port.
2. A port can not be set as the mirrored port and the mirroring port simultaneously.
3. The Port Mirror function can take effect span the multiple VLANs.
5.1.3 Port Security
MAC Address Table maintains the mapping relationship between the port and the MAC address of the connected device, which is the base of the packet forwarding. The capacity of MAC Address
Table is fixed. MAC Address Attack is the attack method that the attacker takes to obtain the network information illegally. The attacker uses tools to generate the cheating MAC address and quickly occupy the MAC Address Table. When the MAC Address Table is full, the switch will broadcast the packets to all the ports. At this moment, the attacker can obtain the network information via various sniffers and attacks. When the MAC Address Table is full, the packets traffic will flood to all the ports, which results in overload, lower speed, packets drop and even breakdown of the system.
Port Security is to protect the switch from the malicious MAC Address Attack by limiting the maximum number of MAC addresses that can be learned on the port. The port with Port Security feature enabled will learn the MAC address dynamically. When the learned MAC address number reaches the maximum, the port will stop learning. Thereafter, the other devices with the MAC address unlearned can not access to the network via this port.
Choose the menu
Switching → Port → Port Security
to load the following page.
33
Figure 5-4 Port Security
The following entries are displayed on this screen:
Port Security
Select:
Port:
Max Learned MAC:
Learned Num:
Learn Mode:
Status:
Select the desired port for Port Security configuration. It is multi-optional.
Displays the port number.
Specify the maximum number of MAC addresses that can be learned on the port.
Displays the number of MAC addresses that have been learned on the port.
Select the Learn Mode for the port.
Dynamic:
When Dynamic mode is selected, the learned
MAC address will be deleted automatically after the aging time.
Static:
When Static mode is selected, the learned MAC address will be 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.
Permanent:
When Permanent mode is selected, the learned MAC address will be out of the influence of the aging time and can only be deleted manually. The learned entries will be saved even the switch is rebooted.
Select Enable/Disable the Port Security feature for the port.
Note:
1. The Port Security function is disabled for the LAG port member. Only the port is removed from
34
the LAG, will the Port Security function be available for the port.
2. The Port Security function is disabled when the 802.1X function is enabled.
5.1.4 Port Isolation
Port Isolation provides a method of restricting traffic flow to improve the network security by forbidding the port to forward packets to the ports that are not on its forward portlist.
Choose the menu
Switching → Port → Port Isolation
to load the following page.
Figure 5-5 Port Isolation Config
The following entries are displayed on this screen:
Port Isolation Config
Port:
Forward Portlist:
Port Isolation List
Port:
Forward Portlist:
Select the port number to set its Forward Portlist.
Select the port that to be forwarded to.
Display the port number.
Display the Forward Portlist.
35
5.1.5 Loopback Detection
With loopback detection feature enabled, the switch can detect loops using loopback detection packets. When a loop is detected, the switch will display an alert or further block the corresponding port according to the port configuration.
Choose the menu
Switching → Port → LoopbackDetection
to load the following page.
Figure 5-6 Loopback Detection Config
The following entries are displayed on this screen:
Global Config
LoopbackDetection
Status:
Detection Interval:
Automatic Recovery
Time:
Web Refresh Status:
Here you can enable or disable Loopback Detection function globally.
Set a Loopback Detection interval between 1 and 1000 seconds.
By default, it’s 30 seconds.
Time after which the blocked port would automatically recover to normal status. It can be set as integral times of detection interval.
Here you can enable or disable web automatic refresh.
36
Web Refresh
Interval:
Port Config
Port Select:
Set a web refresh interval between 3 and 100 seconds. By default, it’s 6 seconds.
Select:
Port
Status
Operation Mode
Recovery Mode
Loop Status
Block Status
LAG
Manual Recover
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for Loopback Detection configuration. It is multi-optional.
Displays the port number.
Enable or disable Loopback Detection function for the port.
Select the mode how the switch processes the detected loops.
Alert:
When a loop is detected, display an alert.
Port based:
When a loop is detected, display an alert and block the port.
Select the mode how the blocked port recovers to normal status.
Auto:
Block status can be automatically removed after recovery time.
Manual:
Block status only can be removed manually.
Displays the port status whether a loopback is detected.
Displays the port status about block or unblock.
Displays the LAG number the port belongs to.
Manually remove the block status of selected ports.
Note:
1. Recovery Mode is not selectable when Alert is chosen in Operation Mode.
2. Loopback Detection must coordinate with storm control.
5.2 LAG
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.
For the member ports in an aggregation group, their basic configuration must be the same. The basic configuration includes
STP
,
QoS
,
GVRP
,
VLAN
,
port attributes
,
MAC Address Learning mode
and other associated settings. The further explains are following:
If the ports, which are enabled for the
GVRP
,
802.1Q VLAN
,
Voice VLAN
,
STP
,
QoS
,
DHCP
Snooping
and
Port Configuration
(
Speed and Duplex
,
Flow Control
), are in a LAG, their configurations should be the same.
The ports, which are enabled for the
Port Security
,
Port Mirror
,
MAC Address Filtering
,
Static MAC Address Binding
and
802.1X Authentication
, can not be added to the LAG.
It’s not suggested to add the ports with
ARP Inspection
and
DoS Defend
enabled to the
LAG.
37
If the LAG is needed, you are suggested to configure the LAG function here before configuring the other functions for the member ports.
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.
Depending on different aggregation modes, aggregation groups fall into two types:
Static LAG
and
LACP Config
. The LAG function is implemented on the
LAG Table
,
Static LAG
and
LACP
Config
configuration pages.
5.2.1 LAG Table
On this page, you can view the information of the current LAG of the switch.
Choose the menu
Switching → LAG → LAG Table
to load the following page.
Figure 5-7 LAG Table
The following entries are displayed on this screen:
Global Config
Aggregate Arithmetic:
Select the applied scope of Aggregate Arithmetic, which results in choosing a port to transfer the packets.
SRC MAC + DST MAC:
When this option is selected, the Aggregate Arithmetic will apply to the source and destination MAC addresses of the packets.
SRC IP + DST IP:
When this option is selected, the
Aggregate Arithmetic will apply to the source and destination IP addresses of the packets.
LAG Table
Select:
Group Number:
Select the desired LAG. It is multi-optional.
Displays the LAG number here.
38
Description:
Member:
Displays the description of LAG.
Displays the LAG member.
Operation:
Allows you to view or modify the information for each LAG.
Edit: Click to modify the settings of the LAG.
Detail: Click to get the information of the LAG.
Click the
Detail
button for the detailed information of your selected LAG.
Figure 5-8 Detail Information
5.2.2 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 5-9 Static LAG Config
39
The following entries are displayed on this screen:
LAG Config
Group Number:
Description:
LAG Table
Member Port:
Select a Group Number for the LAG.
Displays the description of LAG.
Select the port as the LAG member. Clearing all the ports of the LAG will delete this LAG.
Tips:
1. The LAG can be deleted by clearing its all member ports.
2. A port can only be added to a LAG. If a port is the member of a LAG or is dynamically aggregated as the LACP member, the port number will be displayed in gray and can not be selected.
5.2.3 LACP Config
LACP (Link Aggregation Control Protocol) is defined in IEEE802.3ad and enables the dynamic link aggregation and disaggregation by exchanging LACP packets with its partner. The switch can dynamically group similarly configured ports into a single logical link, which will highly extend the bandwidth and flexibly balance the load.
With the LACP feature enabled, the port will notify its partner of the system priority, system MAC, port priority, port number and operation key (operation key is determined by the physical properties of the port, upper layer protocol and admin key). The device with higher priority will lead the aggregation and disaggregation. System priority and system MAC decide the priority of the device. The smaller the system priority, the higher the priority of the device is. With the same system priority, the device owning the smaller system MAC has the higher priority. The device with the higher priority will choose the ports to be aggregated based on the port priority, port number and operation key. Only the ports with the same operation key can be selected into an aggregation group. In an aggregation group, the port with smaller port priority will be considered as the preferred one. If the two port priorities are equal; the port with smaller port number is preferred.
After an aggregation group is established, the selected ports can be aggregated together as one port to transmit packets.
On this page, you can configure the LACP feature of the switch.
Choose the menu
Switching → LAG → LACP Config
to load the following page.
40
Figure 5-10 LACP Config
The following entries are displayed on this screen:
Global Config
System Priority:
Specify the system priority for the switch. The system priority and
MAC address constitute the system identification (ID). A lower system priority value indicates a higher system priority. When exchanging information between systems, the system with higher priority determines which link aggregation a link belongs to, and the system with lower priority adds the proper links to the link aggregation according to the selection of its partner.
LACP Config
Port Select:
Select:
Port:
Admin Key:
Port Priority:
Mode
：
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for LACP configuration. It is multi-optional.
Displays the port number.
Specify an Admin Key for the port. The member ports in a dynamic aggregation group must have the same Admin Key.
Specify a Port Priority for the port. This value determines the priority of the port to be selected as the dynamic aggregation group member. The port with smaller Port Priority will be considered as the preferred one. If the two port priorities are equal; the port with smaller port number is preferred.
Specify lacp mode for your selected port.
41
Status:
LAG:
Enable/Disable the LACP feature for your selected port.
Displays the LAG number which the port belongs to.
5.3 Traffic Monitor
The Traffic Monitor function, monitoring the traffic of each port, is implemented on the
Traffic
Summary
and
Traffic Statistics
pages.
5.3.1 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 5-11 Traffic Summary
The following entries are displayed on this screen:
Auto Refresh
Auto Refresh:
Refresh Rate:
Traffic Summary
Allows you to Enable/Disable refreshing the Traffic Summary automatically.
Enter a value in seconds to specify the refresh interval.
Port Select:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
42
Port:
Packets Rx:
Packets Tx:
Octets Rx:
Octets Tx:
Statistics:
Displays the port number.
Displays the number of packets received on the port. The error packets are not counted in.
Displays the number of packets transmitted on the port.
Displays the number of octets received on the port. The error octets are counted in.
Displays the number of octets transmitted on the port.
Click the
Statistics
button to view the detailed traffic statistics of the port.
5.3.2 Traffic Statistics
Traffic Statistics screen displays the detailed traffic information of each port, which facilitates you to monitor the traffic and locate faults promptly.
Choose the menu
Switching → Traffic Monitor → Traffic Statistics
to load the following page.
Figure 5-12 Traffic Statistics
The following entries are displayed on this screen:
Auto Refresh
Auto Refresh:
Refresh Rate:
Statistics
Allows you to Enable/Disable refreshing the Traffic Summary automatically.
Enter a value in seconds to specify the refresh interval.
43
Port:
Received:
Sent:
Broadcast:
Multicast:
Unicast:
Alignment Errors:
UndersizePkts:
Pkts64Octets:
Pkts65to127Octets:
Pkts128to255Octets:
Pkts256to511Octets:
Pkts512to1023Octets:
PktsOver1023Octets:
Collisions:
Enter a port number and click the
Select
button to view the traffic statistics of the corresponding port.
Displays the details of the packets received on the port.
Displays the details of the packets transmitted on the port.
Displays the number of good broadcast packets received or transmitted on the port. The error frames are not counted in.
Displays the number of good multicast packets received or transmitted on the port. The error frames are not counted in.
Displays the number of good unicast packets received or transmitted on the port. The error frames are not counted in.
Displays the number of the received packets that have a bad
Frame Check Sequence (FCS) with a non-integral octet
(Alignment Error) and have a bad FCS with an integral octet
(CRC Error). The length of the packet is between 64 bytes and
1518 bytes.
Displays the number of the received packets (excluding error packets) that are less than 64 bytes long.
Displays the number of the received packets (including error packets) that are 64 bytes long.
Displays the number of the received packets (including error packets) that are between 65 and 127 bytes long.
Displays the number of the received packets (including error packets) that are between 128 and 255 bytes long.
Displays the number of the received packets (including error packets) that are between 256 and 511 bytes long.
Displays the number of the received packets (including error packets) that are between 512 and 1023 bytes long.
Displays the number of the received packets (including error packets) that are over 1023 bytes.
Displays the number of collisions experienced by a port during packet transmissions.
5.4 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 the entries are generated and updated by auto-learning. In the stable networks, the static MAC address entries can enhance the efficiency of packets forwarding remarkably, and the address filtering feature allows the switch to filter the undesired packets and forbid its forwarding so as to improve the network security.
The types and the features of the MAC Address Table are listed as the following:
44
Type
Static
Dynamic
Configuration Way Aging out
Manually binding
Auto-learning
No
Yes
after reboot
Relationship between the address and the port
Being kept The MAC address can not be learned by the other ports in the same VLAN.
Clear The MAC address can be learned by the other ports in the same VLAN.
Being kept - Filtering Manually binding No
Table 5-1 Types and features of Address Table
This function includes four submenus:
Address Table
,
Static Address
,
Dynamic Address
and
Filtering Address
.
5.4.1 Address Table
On this page, you can view all the information of the Address Table.
Choose the menu
Switching → MAC Address → Address Table
to load the following page.
Figure 5-13 Address Table
The following entries are displayed on this screen:
Search Option
MAC Address:
Enter the MAC address of your desired entry.
45
VLAN ID:
Port:
Type:
Enter the VLAN ID of your desired entry.
Select the corresponding port number of your desired entry.
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 address table to display the dynamic address entries only.
Filtering:
This option allows the address table to display the filtering address entries only.
Address Table
MAC Address:
VLAN ID:
Port:
Type:
Aging Status:
Displays the MAC address learned by the switch.
Displays the corresponding VLAN ID of the MAC address.
Displays the corresponding Port number of the MAC address.
Displays the Type of the MAC address.
Displays the Aging status of the MAC address.
5.4.2 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.
46
Figure 5-14 Static Address
The following entries are displayed on this screen:
Create Static Address
MAC Address:
VLAN ID:
Port:
Enter the static MAC Address to be bound.
Enter the corresponding VLAN ID of the MAC address.
Select a port from the pull-down list 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.
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
Select:
MAC Address:
VLAN ID:
Port:
Type:
Select the entry to delete or modify the corresponding port number. It is multi-optional.
Displays the static MAC Address.
Displays the corresponding VLAN ID of the MAC address.
Displays the corresponding Port number 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.
Displays the Type of the MAC address.
47
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 can not be 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 can not be added to the Filtering Address Table or bound to a port dynamically.
4. This static MAC address bound function is not available if the 802.1X feature is enabled.
5.4.3 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.
48
Figure 5-15 Dynamic Address
The following entries are displayed on this screen:
Aging Config
Auto Aging:
Aging Time:
Allows you to Enable/Disable the Auto Aging feature.
Enter the Aging Time for the dynamic address.
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.
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.
LAG ID:
Enter the LAG ID of your desired entry.
Dynamic Address Table
Select:
Select the entry to delete the dynamic address or to bind the MAC address to the corresponding port statically. It is multi-optional.
49
MAC Address:
VLAN ID:
Port:
Type:
Aging Status:
Bind:
Displays the dynamic MAC Address.
Displays the corresponding VLAN ID of the MAC address.
Displays the corresponding port number of the MAC address.
Displays the Type of the MAC address.
Displays the Aging Status of the MAC address.
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 decreases the performance of the switch. 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.
5.4.4 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.
Choose the menu
Switching → MAC Address → Filtering Address
to load the following page.
Figure 5-16 Filtering Address
The following entries are displayed on this screen:
Create Filtering Address
50
MAC Address:
VLAN ID:
Enter the MAC Address to be filtered.
Enter the corresponding VLAN ID of the MAC address.
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 Filtering Address Table.
MAC:
Enter the MAC address of your desired entry.
VLAN ID:
Enter the VLAN ID number of your desired entry.
Filtering Address Table
Select:
MAC Address:
VLAN ID:
Port:
Type:
Aging Status:
Select the entry to delete the corresponding filtering address. It is multi-optional.
Displays the filtering MAC Address.
Displays the corresponding VLAN ID.
Here the symbol “__” indicates no specified port.
Displays the Type of the MAC address.
Displays the Aging Status of the MAC address.
51
Note:
1. The MAC address in the Filtering Address Table can not 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.
52
Chapter 6 VLAN
The traditional Ethernet is a data network communication technology based 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 Lay3 switch, etc.
The following figure illustrates a VLAN implementation.
Figure 6-1 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 change its network configuration.
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 segments. 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
53
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.
6.1 802.1Q 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 6-2 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 in this switch.
（
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 untagged 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.
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, and the egress rule of the port
54
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. When the packets are forwarded by the TRUNK port, its VLAN tag will not be changed.
（
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 VLAN the port belongs to.
PVID
PVID (Port Vlan ID) is the default VID of the port. When the switch receives an untagged 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 untagged 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.
Receiving Packets
Port Type
Untagged Packets Tagged Packets
Forwarding Packets
Access
Trunk
General
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.
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 allowed by the port, the packet will be received.
The packet will be forwarded after removing its
VLAN tag.
The packet will be forwarded with its current
VLAN tag.
If the egress rule of port is
TAG, the packet will be
If the VID of packet is forbidden by the port, forwarded with its current
VLAN tag. the packet will be dropped.
If the egress rule of port is
UNTAG, the packet will be forwarded after removing its
VLAN tag.
Table 6-1 Relationship between Port Types and VLAN Packets Processing
IEEE 802.1Q VLAN function is implemented on the
VLAN Config
and
Port Config
pages.
55
6.1.1 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 6-3 VLAN Table
To ensure the normal communication of the factory switch, the default VLAN of all ports is set to
VLAN1. VLAN1 cannot be modified or deleted.
The following entries are displayed on this screen:
VLAN Table
VLAN ID Select
Select
：
：
Click the
Select
button to quick-select the corresponding entry based on the VLAN ID number you entered.
Select the desired entry to delete the corresponding VLAN. It is multi-optional.
VLAN ID
：
Name
：
Displays the ID number of VLAN.
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.
56
Figure 6-4 Create or Modify 802.1Q VLAN
The following entries are displayed on this screen:
VLAN Config
VLAN ID:
Name:
Check:
Enter the ID number of VLAN.
Give a name to the VLAN for identification.
Click the
Check
is valid or not.
button to check whether the VLAN ID you entered
VLAN Members
Port Select:
Select:
Port:
Link Type:
Click the
Select
button to quick-select the corresponding entry based on the port number you entered.
Select the desired port to be a member of VLAN or leave it blank.
It's multi-optional.
Displays the port number.
Displays the Link Type of the port. It can be reset on Port Config screen.
57
Egress Rule:
Select the Egress Rule for the VLAN port member. The default egress rule is UNTAG.
TAG: All packets forwarded by the port are tagged. The packets contain VLAN information.
UNTAG: Packets forwarded by the port are untagged.
Displays the LAG to which the port belongs.
LAG:
6.1.2 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 6-5 802.1Q VLAN – Port Config
The following entries are displayed on this screen:
VLAN Port Config
Port Select:
Select:
Click the
Select
button to quick-select the corresponding entry based on the port number you entered.
Select the desired port for configuration. It is multi-optional.
Port:
Displays the port number.
58
Link Type:
PVID:
LAG:
VLAN:
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, and the egress rule of the port is TAG. The PVID can be set as the VID number of any VLAN the port belongs to.
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 VLAN the port belongs to.
Enter the PVID number of the port.
Displays the LAG to which the port belongs.
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 6-6 View the Current VLAN of Port
The following entries are displayed on this screen:
VLAN of Port
VLAN ID Select:
VLAN ID
：
VLAN Name:
Operation:
Click the
Select
button to quick-select the corresponding entry based on the VLAN ID number you entered.
Displays the ID number of VLAN.
Displays the user-defined description of VLAN.
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 based 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.
59
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.
6.2 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 based 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.
On this page, you can create MAC VLAN and view the current MAC VLANs in the table.
Choose the menu
VLAN → MAC VLAN
to load the following page.
Figure 6-7 Create and View MAC VLAN
The following entries are displayed on this screen:
VLAN Table
60
MAC Address:
Description:
VLAN ID:
Enter the MAC address.
Give a description to the MAC address for identification.
Enter the ID number of the MAC VLAN. This VLAN should be one of the
802.1Q VLANs the ingress port belongs to.
MAC VLAN Table
MAC Select:
Select:
MAC Address:
Description:
VLAN ID:
Operation:
Click the
Select
button to quick-select the corresponding entry based on the MAC address you entered.
Select the desired entry. It is multi-optional.
Displays the MAC address.
Displays the user-defined description of the MAC address.
Displays the corresponding VLAN ID of the MAC address.
Click the
Edit
button to modify the settings of the entry. And click the
Modify
button to apply your settings.
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 based on its connected device.
2 Create VLAN
3 Create MAC 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.
Required. On the
VLAN → MAC VLAN
page, create the MAC
VLAN. For the device in a MAC VLAN, it’s required to set its connected port of switch to be a member of this VLAN so as to ensure the normal communication.
6.3 Protocol VLAN
Protocol VLAN is another way to classify VLANs based 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 based on their actual applications and services effectively.
Protocol VLAN, another way to classify VLANs based on network protocol, can bind ToS provided in the network to VLAN to realize the specific service. Through protocol VLAN, the switch can analyze the received untagged packets on the port and match the packets with the user-defined protocol template according to different encapsulation formats and the values of the special fields.
If a packet is matched, the switch will add a corresponding VLAN tag to it automatically and thus the data of specific protocol can be automatically assigned to the corresponding VLAN for transmission. The network administrator can manage network clients based on their specific applications and services through protocol VLAN.
61
Encapsulation Format of Ethernet Data
This section simply introduces the common used encapsulation format of Ethernet data to understand the procedure for the switch to identify the protocol of packets. At present there are two encapsulation formats of Ethernet data, Ethernet II encapsulation and 802.2/802.3 encapsulation, shown as follows:
Ethernet II encapsulation
802.2/802.3
DA and SA respectively refer to destination MAC address and source MAC address. The number indicates the length of the field in bytes, for example, the length of source MAC address is 12 bytes.
As the maximum length of Ethernet data is 1500 bytes, that is, 0x05DC in hexadecimal, the
Length field in 802.2/802.3 encapsulation ranges from 0x0000 to 0x05DC, but the Type field in Ethernet II encapsulation ranges from 0x0600 to 0xFFF. The Type or Length field in the range of 0x05DD to 0x05FF is recognized as illegal and will be directly discarded. The switch identifies whether a packet is Ethernet II packet or 802.2/802.3 packet according to the ranges of the two fields.
802.2/802.3 encapsulation contains the following three extended formats:
802.3 raw encapsulation
Only the Length field is encapsulated after source MAC address field and destination MAC address field, followed by DATA field without other fields. Currently only IPX protocol supports
802.3 raw encapsulation format. The last two bytes of the Length field in 802.3 raw encapsulation is 0xFFFF.
802.2LLC (Logic Link Control) encapsulation
The Length field, DSAP (Destination Service Access Point) field, SSAP (Source Service
Access Point) field and Control field are encapsulated after source MAC address field and destination MAC address field. The value of Control field is always 3. DSAP field and SSAP field in 802.2 LLC encapsulation are used to identify the upper layer protocol, for example, when both the two fields are 0xE0, it indicates the upper layer protocol is IPX.
802.2 SNAP (Sub-Network Access Protocol) is encapsulated based on 802.3 standard packets. In 802.2 SNAP encapsulation, the values of both DSAP field and SSAP field are always 0XAA, and the value of Control field is 3. The switch differentiates 802.2 LLC and
802.2 SNAP encapsulation formats according to the values of DSAP field and SSAP field.
The device determines the encapsulation format of its sending packets, and a device can send out packets of two encapsulation formats. Ethernet II encapsulation format is the most common used one currently.
802.3 and Ethernet II encapsulation formats are supported in IP protocol, ARP protocol and RARP protocol, but not supported in all protocols. The switch identifies the protocol of the packets by matching eigenvalues of two encapsulation formats.
62
The Procedure for the Switch to Identify Packet Protoco
l
The Implementation of Protocol VLAN
This switch can match packets through protocol template and transmit packets in the specific
VLAN according to the protocol. Protocol template, comprising encapsulation format and protocol type, is the standard to determine the protocol which a packet belongs to. The following table shows the common used encapsulation formats supported in network layer protocol and the protocol templates are for reference. Meanwhile some protocol templates has been preset in the switch, you can create protocol VLAN according to the corresponding protocol template.
Encapsulation
Protocol
IP
（
0x0800
）
Ethernet II
Supported
802.3 raw
Not supported
802.2 LLC
Not supported
802.2 SNAP
Supported
IPX
（
0x8137
）
AppleTalk （ 0x809B ）
Supported Supported Supported Supported
Supported
Not supported
Not supported
Supported
Table 6-2 Protocol types in common use
The packet in Protocol VLAN is processed in the following way:
63
VLAN packets are 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 based 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.
6.3.1 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 6-8 Protocol Group Table
The following entries are displayed on this screen:
Protocol Group Table
Select:
Protocol:
VLAN ID:
Member:
Operation:
Select the desired entry. It is multi-optional.
Displays the protocol of the protocol group.
Displays the corresponding VLAN ID of the protocol group.
Displays the member of the protocol group.
Click the
Edit
button to modify the settings of the entry. And click the
Modify
button to apply your settings.
6.3.2 Protocol Group
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
to load the following page.
64
Figure 6-9 Create Protocol VLAN
The following entries are displayed on this screen:
Protocol Group Config
Protocol:
VLAN ID:
Select the defined protocol template.
Enter the ID number of the Protocol VLAN. This VLAN should be one of the 802.1Q VLANs the ingress port belongs to.
Protocol Group Member
Select your desired port for Protocol VLAN Group.
6.3.3 Protocol Template
The Protocol Template should be created before configuring the Protocol VLAN. By default, the switch has defined the IP Template, ARP Template, RARP Template, etc. You can add more
Protocol Template on this page.
Choose the menu
VLAN → Protocol VLAN → Protocol Template
to load the following page.
Figure 6-10 Create and View Protocol Template
65
The following entries are displayed on this screen:
Create Protocol Template
Protocol Name:
Ether Type:
Frame Type:
Protocol Template Table
Give a name for the Protocol Template.
Enter the Ethernet protocol type field in the protocol template.
Select a Frame Type for the Protocol Template.
Select:
ID
Protocol Name:
Ether Type:
Frame Type
Select the desired entry. It is multi-optional.
Displays the index of the protocol template.
Displays the name of the protocol template.
Displays the Ethernet protocol type field in the protocol template.
Displays the Frame type field for the protocol template.
Note:
The Protocol Template bound to VLAN can not be deleted.
Configuration Procedure:
Step Operation
1 Set the link type for port.
Description
Required. On the
VLAN → 802.1Q VLAN → Port Config
page, set the link type for the port based on its connected device.
2 Create VLAN.
Protocol Required. On the
VLAN → Protocol VLAN → Protocol
Template
page, create the Protocol Template before configuring Protocol VLAN.
4 Create Protocol VLAN. Required. On the
VLAN → Protocol VLAN → Protocol
VLAN
page, select the protocol type and enter the VLAN ID to create a Protocol VLAN.
5 Modify/View VLAN. Optional. On the
VLAN → Protocol VLAN → Protocol VLAN
page, click the
Edit
button to modify/view the information of the corresponding VLAN.
6 Delete 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.
Optional. On the
VLAN → Protocol VLAN → Protocol VLAN
page, select the desired entry to delete the corresponding
VLAN by clicking the
Delete
button.
6.4 Application Example for 802.1Q VLAN
Network Requirements
Switch A is connecting to PC A and Server B;
66
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
the
VLAN → 802.1Q VLAN → Port Config
page, configure
Link Type of the ports the link type of Port 2, Port 3 and Port 4 as ACCESS, TRUNK and
ACCESS respectively
Required.
→ 802.1Q VLAN → VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 2 and Port 3.
Required.
→ 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
the
VLAN → 802.1Q VLAN → Port Config
page, configure
Link Type of the ports the link type of Port 7, Port 6 and Port 8 as ACCESS, TRUNK and
ACCESS respectively.
Required.
→ 802.1Q VLAN → VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 6 and Port 8.
Required.
→ 802.1Q VLAN → VLAN Config
page, create a
VLAN with its VLAN ID as 20, owning Port 6 and Port 7.
67
6.5 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.
Network Diagram
Configuration Procedure
Configure Switch A
Step Operation Description
1
Configure the
Link Type of the
VLAN → 802.1Q VLAN → Port Config
page, configure the link type of Port 11 and Port 12 as GENERAL and TRUNK respectively. ports
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
page, create MAC VLAN10 with the MAC address as 00-19-56-8A-4C-71.
5
Configure MAC
VLAN 20
On
VLAN → MAC VLAN
page, create MAC VLAN10 with the MAC address as 00-19-56-82-3B-70.
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Configure Switch B
Step Operation Description
1 Configure the
VLAN → 802.1Q VLAN → Port Config
page, configure the
Link Type of the ports link type of Port 21 and Port 22 as GENERAL and TRUNK respectively.
On
→ 802.1Q VLAN → VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 21 and Port 22, and configure the egress rule of Port 21 as Untag.
VLAN 10
VLAN 20
On
→ 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.
MAC
VLAN → MAC VLAN
page, create MAC VLAN10 with the MAC address as 00-19-56-8A-4C-71.
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
VLAN → 802.1Q VLAN → Port Config
page, configure the
Link Type of the ports link type of Port 2 and Port 3 as GENERAL, and configure the link type of Port 4 and Port 5 as ACCESS.
On
→ 802.1Q VLAN → VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 2, Port 3 and Port 5,
On
→ 802.1Q VLAN → VLAN Config
page, create a
VLAN with its VLAN ID as 20, owning Port 2, Port 3 and Port 4,
6.6 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.
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Network Diagram
Configuration Procedure
Configure Switch A
Step Operation Description
1 Configure the
VLAN → 802.1Q VLAN → Port Config
page, configure the
Link Type of the ports link type of Port 11 and Port 13 as ACCESS, and configure the link type of Port 12 as GENERAL.
On
→ 802.1Q VLAN → VLAN Config
page, create a
VLAN with its VLAN ID as 10, owning Port 12 and Port 13, and configure the egress rule of Port 12 as Untag.
On
→ 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 Untag.
Configure Switch B
Step Operation Description
1 Configure the
VLAN → 802.1Q VLAN → Port Config
page, configure the
Link Type of the ports link type of Port 4 and Port 5 as ACCESS, and configure the link type of
Port 3 as GENERAL.
On
→ 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 Untag.
On
→ 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 Untag.
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Step Operation Description
Protocol
VLAN → Protocol VLAN → Protocol Template
page,
Template configure the protocol template practically. E.g. the IP network packets are encapsulated in Ethernet II format and its Ether Type is 0800; the
AppleTalk network packets are encapsulated in SNAP format and its
PID is 809B.
Protocol
VLAN → Protocol VLAN → Protocol Group
page, create protocol
VLAN 10 VLAN 10 with Protocol as IP and tick Port 3.
Protocol
VLAN → Protocol VLAN → Protocol Group
page, create protocol
VLAN 20 VLAN 20 with Protocol as AppleTalk and tick Port 3.
6.7 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.
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.
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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.
In this switch, only the port with TRUNK link type can be set as the GVRP application entity to maintain the VLAN registration information. GVRP has the following three port registration modes:
Normal, Fixed, and Forbidden.
Normal:
In this mode, a port can dynamically register/deregister a VLAN and propagate the dynamic/static VLAN information.
Fixed:
In this mode, a port cannot register/deregister a VLAN dynamically. It only propagates static VLAN information. That is, the port in Fixed mode only permits the packets of its static
VLAN to pass.
Forbidden:
In this mode, a port cannot register/deregister VLANs. It only propagates VLAN 1 information. That is, the port in Forbidden mode only permits the packets of the default VLAN
(namely VLAN 1) to pass.
Choose the menu
VLAN → GVRP
to load the following page.
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Figure 6-11 GVRP Config
Note:
If the GVRP feature is enabled for a member port of LAG, please ensure all the member ports of this LAG are set to be in the same status and registration mode.
The following entries are displayed on this screen:
Global Config
Allows you to Enable/Disable the GVRP function.
GVRP:
Port Config
Port Select:
Select:
Port:
Status:
Registration
Mode:
Click the
Select
button to quick-select the corresponding entry based on the port number you entered.
Select the desired port for configuration. It is multi-optional.
Displays the port number.
Enable/Disable the GVRP feature for the port. The port type should be set to TRUNK before enabling the GVRP feature.
Select the Registration Mode for the port.
Normal:
In this mode, a port can dynamically register/deregister a VLAN and propagate the dynamic/static VLAN information.
Fixed:
In this mode, a port cannot register/deregister a VLAN dynamically. It only propagates static VLAN information.
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LeaveAll Timer:
Join Timer:
Leave Timer:
Forbidden:
In this mode, a port cannot register/deregister
VLANs. It only propagates VLAN 1 information.
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. The LeaveAll Timer ranges from 1000 to 30000 centiseconds.
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 20 to 1000 centiseconds.
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 60 to 3000 centiseconds.
Displays the LAG to which the port belongs.
LAG:
Note:
LeaveAll Timer >= 10* Leave Timer, Leave Timer >= 2*Join Timer
Configuration Procedure:
Step Operation
1 Set the link type for port.
Description
Required. On the
VLAN → 802.1Q VLAN → Port Config
page, set the link type of the port to be TRUNK.
2 Enable GVRP function. Required. On the
VLAN → GVRP
page, enable GVRP function.
3 Configure the registration Required. On the
VLAN → GVRP
page, configure the mode and the timers for the port. parameters of ports based on actual applications.
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Chapter 7 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
）
: Indicates the value of the priority and MAC address of the bridge.
Bridge ID can be configured and the switch with the lower bridge ID has the higher priority.
Root Bridge
: Indicates the switch has the lowest bridge ID. Configure the best PC 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 network segment. BPDUs are forwarded to the network segment through the designated bridge. The switch with the lowest bridge ID will be chosen as the designated bridge.
Root Path Cost
: Indicates the sum of the path cost of the root port and the path cost of all the switches that packets pass through. The root path cost of the root bridge is 0.
Bridge Priority
: The bridge priority can be set to a value in the range of 0~32768. The lower value priority has the higher priority. The switch with the higher priority has more chance to be chosen as the root bridge.
Root Port
: Indicates the port that has the lowest 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.
Port Priority
: The port priority can be set to a value in the range of 0~255. The lower value priority has the higher priority. The port with the higher priority has more chance to be chosen as the root port.
Path Cost
: Indicates the parameter for choosing the link path by STP. By calculating the path cost,
STP chooses the better links and blocks the redundant links so as to disbranch the ring-network to form a tree-topological ring-free network.
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 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 is the designated port of switch A and port 4 is the designated port of switch B; port 6 is the blocked port of switch C.
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Figure 7-1 Basic STP diagram
STP Timers
Hello Time:
Hello Time ranges from 1 to 10 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 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.
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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
2
If the priority of the BPDU received on the port is lower than that of the BPDU if of the port itself, the switch discards the BPDU and does not change the BPDU of the port.
If the priority of the BPDU is higher than that of the BPDU of the port itself, the switch replaces the BPDU of the port with the received one and compares it with those of other ports on the switch to obtain the one with the highest priority.
Table 7-1 Comparing BPDUs
Selecting the root bridge
The root bridge is selected by BPDU comparing. The switch with the smallest root ID is chosen as the root bridge.
Selecting the root port and designate port
The operation is taken in the following way:
Step Operation
1 For each switch (except the one chosen as the root bridge) in a network, the port that receives the BPDU with the highest priority is chosen as the root port of the switch.
2 Using the root port BPDU and the root path cost, the switch generates a designated port BPDU for each of its ports.
Root ID is replaced with that of the root port;
Root path is replaced with the sum of the root path cost of the root port and the path cost between this port and the root port;
The ID of the designated bridge is replaced with that of the switch;
The ID of the designated port is replaced with that of the port.
3 The switch compares the resulting BPDU with the BPDU of the desired port whose role you want to determine.
If the resulting BPDU takes the precedence over the BPDU of the port, the port is chosen as the designated port and the BPDU of this port is replaced with the resulting BPDU. The port regularly sends out the resulting BPDU;
If the BPDU of this port takes the precedence over the resulting BPDU, the
BPDU of this port is not replaced and the port is blocked. The port only can receive BPDUs.
Table 7-2 Selecting root port and designated port
Tips
：
In a STP with stable 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 premises for the port in the RSTP to transit its state rapidly are as follows.
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The condition for the root port to transit its port state rapidly: The old root port of the switch stops forwarding data and the designated port of the upstream switch begins to forward data.
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-to-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.
MSTP is compatible with both STP and RSTP.
MSTP Elements
MST Region
(Multiple Spanning Tree Region): An MST Region comprises switches with the same region configuration and VLAN-to-Instances mapping relationship.
IST
(Internal Spanning Tree)
:
An IST is a spanning tree in an MST.
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.
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Figure 7-2 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 tree 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
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: Indicates the port that has the lowest 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.
The following diagram shows the different port roles.
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Figure 7-3 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
.
7.1 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.
7.1.1 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 instance. 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 7-4 STP Config
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The following entries are displayed on this screen:
Global Config
STP:
Version:
Select Enable/Disable STP function globally on the switch.
Select the desired STP version on the switch.
STP: Spanning Tree Protocol.
RSTP: Rapid Spanning Tree Protocol.
MSTP: Multiple Spanning Tree Protocol.
Parameters Config
CIST Priority:
Hello Time
Max Age:
Forward Delay:
TxHold Count:
Max Hops:
Enter a value from 0 to 61440 to specify the priority of the switch for comparison in the CIST. CIST priority is an important criterion on determining the root bridge. In the same condition, the switch with the highest priority will be chosen as the root bridge. The lower value has the higher priority. The default value is 32768 and should be exact divisor of 4096.
Enter a value from 1 to 10 in seconds to specify the interval to send BPDU packets. It is used to test the links. 2*(Hello Time + 1)
≤ Max Age. The default value is 2 seconds.
Enter a value from 6 to 40 in seconds to specify the maximum time the switch can wait without receiving a BPDU before attempting to reconfigure. The default value is 20 seconds.
Enter a value from 4 to 30 in seconds to specify the time for the port to transit its state after the network topology is changed.
2*(Forward Delay-1) ≥ Max Age. The default value is 15 seconds.
Enter a value from 1 to 20 to set the maximum number of BPDU packets transmitted per Hello Time interval. The default value is
5pps.
Enter a value from 1 to 40 to set the maximum number of hops that occur in a specific region before the BPDU is discarded. The default value is 20 hops.
Note:
1. 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.
2. An adequate hello time parameter can enable the switch to discover the link failures occurred in the network without occupying too much network resources. A too large hello time parameter may result in normal links being regarded as invalid when packets drop occurred in the links, which in turn result in spanning tree being regenerated. A too small hello time parameter may result in duplicated configuration being sent frequently, which increases the network load of the switches and wastes network resources. 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.
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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.
7.1.2 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 7-5 STP Summary
7.2 Port Config
On this page you can configure the parameters of the ports for CIST
Choose the menu
Spanning Tree → Port Config
to load the following page.
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Figure 7-6 Port Config
The following entries are displayed on this screen:
Port Config
Port Select:
Select:
Port:
Status:
Priority:
ExtPath:
IntPath:
Edge Port:
P2P Link:
MCheck:
STP Version:
Port Role:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for STP configuration. It is multi-optional.
Displays the port number of the switch.
Select Enable /Disable STP function for the desired port.
Enter a value from 0 to 240 divisible by 16. Port priority is an important criterion on determining if the port connected to this port will be chosen as the root port. The lower value has the higher priority.
ExtPath Cost is used to choose the path and calculate the path costs of ports in different MST regions. It is an important criterion on determining the root port. The lower value has the higher priority.
IntPath Cost is used to choose the path and calculate the path costs of ports in an MST region. It is an important criterion on determining the root port. The lower value has the higher priority.
Select Enable/Disable Edge Port. The edge port can transit its state from blocking to forwarding rapidly without waiting for forward delay.
Select the P2P link status. If the two ports in the P2P link are root port or designated port, they can transit their states to forwarding rapidly to reduce the unnecessary forward delay.
Select Enable to perform MCheck operation on the port. Unchange means no MCheck operation.
Displays the STP version of the port.
Displays the role of the port played in the STP Instance.
Root Port: Indicates the port that has the lowest path cost from this bridge to the Root Bridge and forwards packets to the root.
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Port Status:
LAG:
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.
Displays the working status of the port.
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.
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. All the links of ports in a LAG can be configured as point-to-point links.
3. 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.
7.3 MSTP Instance
MSTP combines VLANs and spanning tree together via VLAN-to-instance mapping table
(VLAN-to-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-to-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.
7.3.1 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.
84
Figure 7-7 Region Config
The following entries are displayed on this screen:
Region Config
Region Name:
Revision:
Create a name for MST region identification using up to 32 characters.
Enter the revision from 0 to 65535 for MST region identification.
7.3.2 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 7-8 Instance Config
The following entries are displayed on this screen:
Instance Table
Instance ID Select:
Click the
Select
button to quick-select the corresponding Instance ID
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Select:
Instance:
Status:
Priority:
VLAN ID:
Clear:
based on the ID number you entered.
Select the desired Instance ID for configuration. It is multi-optional.
Displays Instance ID of the switch.
Displays status of the instance.
Enter the priority of the switch in the instance. It is an important criterion on determining if the switch will be chosen as the root bridge in the specific instance.
Enter the VLAN ID which belongs to the corresponding instance ID.
After modification here, the previous VLAN ID will be cleared and mapped to the CIST.
Click the
Clear
button to clear up all VLAN IDs from the instance ID.
The cleared VLAN ID will be automatically mapped to the CIST.
VLAN-Instance Mapping
VLAN ID:
Instance ID:
Enter the desired VLAN ID. After modification here, the new VLAN ID will be added to the corresponding instance ID and the previous VLAN
ID won’t be replaced.
Enter the corresponding instance ID.
Note:
In a network with both GVRP and MSTP enabled, GVRP packets are forwarded along the CIST. If you want to broadcast packets of 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.
7.3.3 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 instance IDs as well as view status of the ports in the specified instance.
Choose the menu
Spanning Tree → MSTP Instance → Instance Port Config
to load the following page.
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Figure 7-9 Instance Port Config
The following entries are displayed on this screen:
Port Config
Instance ID:
Port Select:
Select:
Port:
Priority:
Path Cost:
Port Role:
Port Status:
LAG:
Select the desired instance ID for its port configuration.
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port to specify its priority and path cost. It is multi-optional.
Displays the port number of the switch.
Enter the priority of the port in the instance. It is an important criterion on determining if the port connected to this port will be chosen as the root port.
Path Cost is used to choose the path and calculate the path costs of ports in an MST region. It is an important criterion on determining the root port. The lower value has the higher priority.
Displays the role of the port played in the MSTP Instance.
Displays the working status of the port.
Displays the LAG number which the port belongs to.
Note:
The port status of one port in different spanning tree instances can be different.
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Global configuration Procedure for Spanning Tree function:
Step Operation
1 Make clear roles the switches instances: root bridge or designated bridge
Description
Preparation. play in spanning tree parameters
MSTP Enable Spanning Tree function on the switch and configure MSTP parameters on
Spanning
Tree → STP Config → STP Config
page.
4 for ports
Configure the MST region
Spanning Tree → Port Config → Port Config
page.
Required. Create MST region and configure the role the switch plays in the MST region on
Spanning
Tree → MSTP Instance → Region Config
and
Instance
Config
page. for instance ports and configure MSTP parameters for instance ports on
Spanning Tree → MSTP Instance → Instance Port
Config
page.
7.4 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
and
TC Protect
pages.
Port Protect function is to prevent the devices from any malicious attack against STP features.
7.4.1 Port Protect
On this page you can configure loop protect feature, root protect feature, TC protect feature,
BPDU protect feature and BPDU filter feature for ports. You are suggested to enable corresponding protection feature for the qualified ports.
Loop Protect
In a stable network, a switch maintains the states of ports by receiving and processing BPDU packets from the upstream switch. However, when link congestions or link failures occurred to the network, a down stream switch does not receive BPDU packets for certain period, which results in spanning trees being regenerated and roles of ports being reselected, and causes the blocked ports to transit to forwarding state. Therefore, loops may be incurred in the network.
The loop protect function can suppresses loops. With this function enabled, a port, regardless of the role it plays in instances, is always set to blocking state, when the port does not receive BPDU packets from the upstream switch and spanning trees are regenerated, and thereby loops can be prevented.
Root Protect
A CIST and its secondary root bridges are usually located in the high-bandwidth core region.
Wrong configuration or malicious attacks may result in configuration BPDU packets with higher priorities being received by the legal root bridge, which causes the current legal root bridge to lose
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its position and network topology jitter to occur. In this case, flows that should travel along high-speed links may lead to low-speed links, and network congestion may occur.
To avoid this, MSTP provides root protect function. Ports with this function enabled can only be set as designated ports in all spanning tree instances. When a port of this type receives BDPU packets with higher priority, it transits its state to blocking state and stops forwarding packets (as if it is disconnected from the link). The port resumes the normal state if it does not receive any configuration BPDU packets with higher priorities for a period of two times of forward delay.
TC Protect
A switch removes MAC address entries upon receiving TC-BPDU packets. If a user maliciously sends a large amount of TC-BPDU packets 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.
To prevent the switch from frequently removing MAC address entries, you can enable the TC protect function on the switch. With TC protect function enabled, if the account number of the received TC-BPDUs exceeds the maximum number you set in the TC threshold field, the switch will not performs the removing operation in the TC protect cycle. Such a mechanism prevents the switch from frequently removing MAC address entries.
BPDU Protect
Ports of the switch directly connected to PCs or servers are configured as edge ports to rapidly transit their states. When these ports receive BPDUs, the system automatically configures these ports as non-edge ports and regenerates spanning trees, which may cause network topology jitter.
Normally these ports do not receive BPDUs, but if a user maliciously attacks the switch by sending
BPDUs, network topology jitter occurs.
To prevent this attack, MSTP provides BPDU protect function. With this function enabled on the switch, the switch shuts down the edge ports that receive BPDUs and reports these cases to the administrator. If a port is shut down, only the administrator can restore it.
BPDU Filter
BPDU filter function is to prevent BPDUs flood in the STP network. If a switch receives malicious
BPDUs, it forwards these BPDUs to the other switched in the network, which may result in spanning trees being continuously regenerated. In this case, the switch occupying too much CPU or the protocol status of BPDUs is wrong.
With BPDU filter function enabled, a port does not receive or forward BPDUs, but it sends out its own BPDUs. Such a mechanism prevents the switch from being attacked by BPDUs so as to guarantee generation the spanning trees correct.
Choose the menu
Spanning Tree → STP Security → Port Protect
to load the following page.
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Figure 7-10 Port Protect
The following entries are displayed on this screen:
Port Protect
Port Select:
Select:
Port:
Loop Protect:
Root Protect:
TC Protect:
BPDU Protect:
BPDU Filter:
LAG:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for port protect configuration. It is multi-optional.
Displays the port number of the switch.
Loop Protect is to prevent the loops in the network brought by recalculating STP because of link failures and network congestions.
Root Protect is to prevent wrong network topology change caused by the role change of the current legal root bridge.
TC Protect is to prevent the decrease of the performance and stability of the switch brought by continuously removing MAC address entries upon receiving TC-BPDUs in the STP network.
BPDU Protect is to prevent the edge port from being attacked by maliciously created BPDUs
BPDU Filter is to prevent BPDUs flood in the STP network.
Displays the LAG number which the port belongs to.
7.4.2 TC Protect
When TC Protect is enabled for the port on
Port Protect
page, the TC threshold and TC protect cycle need to be configured on this page.
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Choose the menu
Spanning Tree → STP Security → TC Protect
to load the following page.
Figure 7-11 TC Protect
The following entries are displayed on this screen:
TC Protect
TC Threshold:
Enter a number from 1 to 100. It is the maximum number of the
TC-BPDUs received by the switch in a TC Protect Cycle. The default value is 20.
TC Protect Cycle:
Enter a value from 1 to 10 to specify the TC Protect Cycle. The default value is 5.
7.5 Application Example for STP 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 the STP with B as the root bridge. The data in VLAN102, 104 and 106 are transmitted in the STP with C as the root bridge.
Network Diagram
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Configuration Procedure
Configure Switch A:
Step Operation Description
On
→ 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.
On
→ STP Config → STP Config
page, enable STP function and select MSTP version.
On
Spanning Tree → STP 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-to-Instance
Spanning Tree → MSTP Instance → Instance
mapping table of the MST region
Config
page, configure VLAN-to-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
On
→ 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.
On
→ STP Config → STP Config
page, enable STP function and select MSTP version.
On
Spanning Tree → STP 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-to-Instance
Spanning Tree → MSTP Instance → Instance
mapping table of the MST region
Config
page, configure VLAN-to-Instance mapping table. Map VLAN 101, 103 and 105 to Instance 1; map
VLAN 102, 104 and 106 to Instance 2.
5 Configure switch B as the root bridge of Instance 1
On
Spanning Tree → MSTP Instance → Instance
Config
page, configure the priority of Instance 1 to be 0.
6 Configure switch B as the On
Spanning Tree → MSTP Instance → Instance
designated bridge of Instance 2
Config
4096.
page, configure the priority of Instance 2 to be
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Configure Switch C:
Step Operation Description
On
→ 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.
On
→ STP Config → STP Config
page, enable STP function and select MSTP version.
On
Spanning Tree → STP 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-to-Instance
Spanning Tree → MSTP Instance → Instance
mapping table of the MST region
Config
page, configure VLAN-to-Instance mapping table. Map VLAN 101, 103 and 105 to Instance 1; map
VLAN 102, 104 and 106 to Instance 2.
5 Configure switch C as the root 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 Instance 2 to be 0.
Configure Switch D:
Step Operation Description
On
→ 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.
On
→ STP Config → STP Config
page, enable STP function and select MSTP version.
On
Spanning Tree → STP 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-to-Instance
Spanning Tree → MSTP Instance → Instance
mapping table of the MST region
Config
page, configure VLAN-to-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.
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Chapter 8 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
Figure 8-1 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;
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.
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Multicast 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 8-1 Range of the special multicast IP
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 Figure 8-2.
Figure 8-2 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 addresses.
Multicast Address Table
The switch is forwarding multicast packets based on the multicast address table. As the transmission of multicast packets can not 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 entry can not 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 8-3 below.
VLAN ID Multicast IP Port
Figure 8-3 Multicast Address Table
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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
and
Packet Statistics
.
8.1 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 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.
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3. IGMP Leave Message
The host, running IGMPv1, does not send IGMP leave message when leaving a multicast group, as a result, the switch can not 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 switch 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.
8.1.1 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.
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Figure 8-4 Basic Config
The following entries are displayed on this screen:
Global Config
IGMP Snooping:
Unknown Multicast:
Select Enable/Disable IGMP Snooping function globally on the switch.
Select the operation for the switch to process unknown multicast,
Forward or Discard.
IGMP Snooping Status
Description:
Member:
Displays IGMP Snooping status.
Displays the member of the corresponding status.
8.1.2 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.
99
Figure 8-5 Port Config
The following entries are displayed on this screen:
Port Config
Port Select:
Select:
Port:
IGMP Snooping:
Fast Leave:
LAG:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for IGMP Snooping feature configuration. It is multi-optional.
Displays the port of the switch.
Select Enable/Disable IGMP Snooping for the desired port.
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 the multicast group upon receiving IGMP leave messages.
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.
8.1.3 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.
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Figure 8-6 VLAN Config
The following entries are displayed on this screen:
VLAN Config
VLAN ID:
Router Port Time:
Member Port Time:
Leave Time:
Static Router Ports:
Enter the VLAN ID to enable IGMP Snooping for the desired
VLAN.
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.
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.
Specify the interval between the switch receiving a leave message from a host and the switch removing the host from the multicast groups.
Select the static router ports which are mainly used in the network with stable topology.
VLAN Table
VLAN ID Select:
Select:
VLAN ID:
Router Port Time:
Member Port Time:
Click the
Select
button to quick-select the corresponding VLAN ID based on the ID number you entered.
Select the desired VLAN ID for configuration. It is multi-optional.
Displays the VLAN ID.
Displays the router port time of the VLAN.
Displays the member port time of the VLAN.
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Leave Time:
Router Port:
Displays the leave time of the VLAN.
Displays the router port of the VLAN.
Note:
The settings here will be invalid when multicast VLAN is enabled
Configuration procedure:
Step Operation Description
function and for the port on
Multicast → IGMP
Snooping → Snooping Config
and
Port Config
page.
2 Configure the multicast parameters for VLANs
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.
8.1.4 Multicast VLAN
In old multicast transmission mode, when users in different VLANs apply for join the same multicast group, the multicast router will duplicate this multicast information and deliver each
VLAN owning a receiver one copy. This mode wastes a lot of bandwidth.
The problem above can be solved by configuring a multicast VLAN. By adding switch ports to the multicast VLAN and enabling IGMP Snooping, you can make users in different VLANs share the same multicast VLAN. This saves the bandwidth since multicast streams are transmitted only within the multicast VLAN and also guarantees security because the multicast VLAN is isolated from user VLANS.
Before configuring a multicast VLAN, you should firstly configure a VLAN as multicast VLAN and add the corresponding ports to the VLAN on the
802.1Q VLAN
page. If the multicast VLAN is enabled, the multicast configuration for other VLANs on the
VLAN Config
page will be invalid, that is, the multicast streams will be transmitted only within the multicast VLAN.
Choose the menu
Multicast → IGMP Snooping → Multicast VLAN
to load the following page.
Figure 8-7 Multicast VLAN
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The following entries are displayed on this screen:
Multicast VLAN
Multicast VLAN:
VLAN ID:
Router Port Time:
Member Port Time:
Leave Time:
Router Ports:
Select Enable/Disable Multicast VLAN feature.
Enter the VLAN ID of the multicast VLAN.
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.
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.
Specify the interval between the switch receiving a leave message from a host, and the switch removing the host from the multicast groups.
Select the static router ports which are mainly used in the network with stable topology.
Note:
1. The router port should be in the multicast VLAN, otherwise the member ports can not receive multicast streams.
2. The Multicast VLAN won't take effect unless you first complete the configuration for the corresponding VLAN owning the port on the
802.1Q VLAN
page.
3. The link type of the member ports in the multicast VLAN can only be GENERAL.
4. Configure the link type of the router port in the multicast VLAN as TRUNK or configure the egress rule as TAG and the link type as GENERAL otherwise all the member ports in the multicast VLAN can not receive multicast streams.
5. After a multicast VLAN is created, all the IGMP packets will be processed only within the multicast VLAN.
Configuration procedure:
Step Operation Description
2 function
Create a multicast VLAN and for the port on
Multicast → IGMP
Snooping → Snooping Config
and
Port Config
page.
Required. Create a multicast VLAN and add all the member ports and router ports to the VLAN on the
VLAN → 802.1Q
VLAN
page.
Configure the link type of the member ports as
GENERAL.
Configure the link type of the router ports as TRUNK or configure the egress rule as tagged GENERAL.
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Step Operation Description
4 multicast VLAN
Multicast → IGMP Snooping → Multicast VLAN
page.
It is recommended to keep the default time parameters.
Look over the configuration If it is successfully configured, the VLAN ID of the multicast
VLAN will be displayed in the IGMP Snooping Status table on the
Multicast → IGMP Snooping → Snooping Config
page.
Application Example for Multicast VLAN:
Network Requirements
Multicast source sends multicast streams via the router, and the streams are transmitted to user A and user B through the switch.
Router: Its WAN port is connected to the multicast source; its LAN port is connected to the switch.
The multicast packets are transmitted in VLAN3.
Switch: Port 3 is connected to the router and the packets are transmitted in VLAN3; port 4 is connected to user A and the packets are transmitted in VLAN4; port 5 is connected to user B and the packets are transmitted in VLAN5.
User A: Connected to Port 4 of the switch.
User B: Connected to port 5 of the switch.
Configure a multicast VLAN, and user A and B receive multicast streams through the multicast
VLAN.
Network Diagram
Configuration Procedure
104
Step Operation
1 Create VLANs
Description
Create three VLANs with the VLAN ID 3, 4 and 5 respectively, and specify the description of VLAN3 as Multicast VLAN on
VLAN → 802.1Q VLAN
page.
2 Configure
VLAN → 802.1Q VLAN
function pages.
For port 3, configure its link type as GENERAL and its egress rule as TAG, and add it to VLAN3, VLAN4 and VLAN5.
For port 4, configure its link type as GENERAL and its egress rule as UNTAG, and add it to VLAN3 and VLAN 4.
For port 5, configure its link type as GENERAL and its egress rule as UNTAG, and add it to VLAN3 and VLAN 5.
3 Enable IGMP
Multicast → IGMP
Snooping function
Snooping → Snooping Config
page. Enable IGMP Snooping function for port 3, port4 and port 5 on
Multicast → IGMP
Snooping → Port Config
page.
5
VLAN VLAN as 3 and keep the other parameters as default on
Multicast → IGMP Snooping → Multicast VLAN
page.
Check Multicast VLAN
3-5
and
Multicast VLAN 3
will be displayed in the IGMP
Snooping Status table on the
Multicast → IGMP
Snooping → Snooping Config
page.
8.2 Multicast IP
In a network, receivers can join different multicast groups appropriate to their needs. The switch forwards multicast streams based on multicast address table. The Multicast IP can be implemented on
Multicast IP Table
,
Static Multicast IP
page.
8.2.1 Multicast IP Table
On this page you can view the multicast IP table on the switch.
Choose the menu
Multicast → Multicast IP → Multicast IP Table
to load the following page.
Figure 8-8 Multicast IP Table
The following entries are displayed on this screen:
105
Search Option
Multicast IP:
VLAN ID:
Port:
Type:
Enter the multicast IP address the desired entry must carry.
Enter the VLAN ID the desired entry must carry.
Select the port number the desired entry must carry.
Select the type the desired entry must carry.
All: Displays all multicast IP entries.
Static: Displays all static multicast IP entries.
Dynamic: Displays all dynamic multicast IP entries.
Multicast IP Table
Multicast IP
VLAN ID:
Forward Port
Type:
Displays multicast IP address.
Displays the VLAN ID of the multicast group.
Displays the forward port of the multicast group.
Displays the type of the multicast IP.
Note:
If the configuration on VLAN Config page and multicast VLAN page is changed, the switch will clear up the dynamic multicast addresses in multicast address table and learn new addresses.
8.2.2 Static Multicast IP
Static Multicast IP table, isolated from dynamic multicast group and multicast filter, is not learned by IGMP Snooping. It can enhance the quality and security for information transmission in some fixed multicast groups.
Choose the menu
Multicast → Multicast IP → Static Multicast IP
to load the following page.
Figure 8-9 Static Multicast IP Table
The following entries are displayed on this screen:
Create Static Multicast
106
Multicast IP:
VLAN ID:
Forward Port:
Search Option
Search Option:
Enter static multicast IP address.
Enter the VLAN ID of the multicast IP.
Enter the forward port of the multicast group.
Select the rules for displaying multicast IP table to find the desired entries quickly.
All: Displays all static multicast IP entries.
Multicast IP: Enter the multicast IP address the desired entry must carry.
VLAN ID: Enter the VLAN ID the desired entry must carry.
Port: Enter the port number the desired entry must carry.
Static Multicast IP Table
Select:
Multicast IP:
VLAN ID:
Forward Port:
Select the desired entry to delete the corresponding static multicast IP. It is multi-optional.
Displays the multicast IP.
Displays the VLAN ID of the multicast group.
Displays the forward port of the multicast group.
8.3 Multicast Filter
When IGMP Snooping is enabled, you can specified the multicast IP-range the ports can join so as to restrict users ordering multicast programs via configuring multicast filter rules.
When applying for a multicast group, the host will send IGMP report message. After receiving the report message, the switch will firstly check the multicast filter rules configured for the receiving port. If the port can be added to the multicast group, it will be added to the multicast address table; if the port can not be added to the multicast group, the switch will drop the IGMP report message.
In that way, the multicast streams will not be transmitted to this port, which allows you to control hosts joining the multicast group.
8.3.1 IP-Range
On this page you can figure the desired IP-ranges to be filtered.
Choose the menu
Multicast → Multicast Filter → IP-Range
to load the following page.
107
Figure 8-10 Multicast Filter
The following entries are displayed on this screen:
Create IP-Range
IP Range ID:
Start Multicast IP:
End Multicast IP:
Enter the IP-range ID.
Enter start multicast IP of the IP-range you set.
Enter end multicast IP of the IP-range you set.
IP-Range Table
IP-Range ID Select:
Select:
IP-Range ID:
Start Multicast IP:
End Multicast IP:
Click the
Select
button to quick-select the corresponding IP-range
ID based on the ID number you entered.
Select the desired entry to delete or modify the corresponding
IP-range. It is multi-optional.
Displays IP-range ID.
Displays start multicast IP of the IP-range.
Displays end multicast IP of the IP-range.
8.3.2 Port Filter
On this page you can configure the multicast filter rules for port. Take the configuration on this page and the configuration on IP-Range page together to function to implement multicast filter function on the switch.
Choose the menu
Multicast → Multicast Filter → Port Filter
to load the following page.
108
Figure 8-11 Port Filter
The following entries are displayed on this screen:
Port Filter Config
Port Select:
Select:
Port:
Filter:
Action Mode:
Bound IP-Range (ID):
Max Groups:
LAG:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for multicast filtering. It is multi-optional.
Displays the port number.
Select Enable/Disable multicast filtering feature on the port.
Select the action mode to process multicast packets when the multicast IP is in the filtering IP-range.
Permit: Only the multicast packets whose multicast IP is in the
IP-range will be processed.
Deny: Only the multicast packets whose multicast IP is not in the IP-range will be processed.
Enter the IP-range ID the port will be bound to. The binding
IP-range IDs of the port can be cleared by entering null value in this field and click
Apply
button to submit the configuration.
Specify the maximum number of multicast groups to prevent some ports taking up too much bandwidth.
Displays the LAG number which the port belongs to.
Note:
1. Multicast Filter feature can only have effect on the VLAN with IGMP Snooping enabled.
2. Multicast Filter feature has no effect on static multicast IP.
109
3. Up to 5 IP-Ranges can be bound to one port.
Configuration Procedure:
Step Operation Description
1 Configure Configure IP-Range to be filtered on
Multicast → Multicast Filter → IP-Range
page.
2 Configure multicast filter rules for ports
Optional. Configure multicast filter rules for ports on
Multicast → Multicast Filter → Port Filter
page.
8.4 Packet Statistics
On this page you can view the multicast data traffic on each port of the switch, which facilitates you to monitor the IGMP messages in the network.
Choose the menu
Multicast → Packet Statistics
to load the following page.
Figure 8-12 Packet Statistics
The following entries are displayed on this screen:
Auto Refresh
Auto Refresh:
Refresh Period:
Select Enable/Disable auto refresh feature.
Enter the time from 3 to 300 in seconds to specify the auto refresh period.
110
IGMP Statistics
Port Select:
Port:
Query Packet:
Report Packet (V1):
Report Packet (V2):
Report Packet (V3):
Leave Packet:
Error Packet:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Displays the port number of the switch.
Displays the number of query packets the port received.
Displays the number of IGMPv1 report packets the port received.
Displays the number of IGMPv2 report packets the port received.
Displays the number of IGMPv3 report packets the port received.
Displays the number of leave packets the port received.
Displays the number of error packets the port received.
111
Chapter 9 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 9-1 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 four schedule modes: SP, WRR, SP+WRR and Equ.
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.
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.
112
Figure 9-2 802.1Q 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.
Figure 9-3 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; 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 four scheduling queues,
TC0, TC1, TC2 and TC3. TC0 has the lowest priority while TC3 has the highest priority. The switch provides four schedule modes: SP, WRR, SP+WRR and Equ. whole bandwidth. Packets in the queue with lower priority are sent only when the queue with higher priority is empty. The switch has four egress queues labeled as TC0, TC1, TC2 and
TC3. In SP mode, their priorities increase in order. TC3 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.
113
Figure 9-4 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 can not 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 and TC3 is 1:2:4:8.
Figure 9-5 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, TC3 is in the SP group; TC0, TC1 and TC2 belong to the WRR group and the weight value ratio of TC0, TC1 and TC2 is 1:2:4. In this way, when scheduling queues, the switch allows TC3 to occupy the whole bandwidth following the SP mode and the TC0, TC1 and TC2 in the WRR group will take up the bandwidth according to their ratio 1:2:4.
4. Equ-Mode: Equal-Mode. In this mode, all the queues occupy the bandwidth equally. The weight value ratio of all the queues is 1:1:1:1.
114
The QoS module is mainly for traffic control and priority configuration, including three submenus:
DiffServ
,
Bandwidth Control
and
Voice VLAN
.
9.1 DiffServ
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.
This switch implements three priority modes based on port, on 802.1P and on DSCP, and supports four queue scheduling algorithms. The port priorities are labeled as CoS0, CoS1… CoS7.
The DiffServ function can be implemented on
Port Priority
,
DSCP Priority
,
802.1P/CoS mapping
and
Schedule Mode
pages.
9.1.1 Port Priority
On this page you can configure the port priority.
Choose the menu
QoS → DiffServ → Port Priority
to load the following page.
Figure 9-6 Port Priority Config
The following entries are displayed on this screen:
Port Priority Config
Select:
Port:
Priority:
LAG:
Configuration Procedure:
Select the desired port to configure its priority. It is multi-optional.
Displays the physical port number of the switch.
Specify the priority for the port.
Displays the LAG number which the port belongs to.
115
Step Operation
1 Select the port priority
Description
Required. On
QoS → DiffServ → Port Priority
page, configure the port priority.
2 Configure the mapping
QoS → DiffServ → 802.1P/CoS mapping
relation between the CoS page, configure the mapping relation between the CoS priority and TC and TC.
3 Select a schedule mode Required. On
QoS → DiffServ → Schedule Mode
page, select a schedule mode.
9.1.2 DSCP Priority
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 DSCP
Priority is enabled, 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 8021.1P Priority mode is enabled; the untagged non-IP datagram are mapped based on port priority mode.
Choose the menu
QoS → DiffServ → DSCP Priority
to load the following page.
Figure 9-7 DSCP Priority
The following entries are displayed on this screen:
DSCP Priority Config
DSCP Priority:
Select Enable or Disable DSCP Priority.
Priority Level
116
DSCP:
Indicates the priority determined by the DS region of IP datagram.
It ranges from 0 to 63.
Priority:
Indicates the 802.1P priority the packets with tag are mapped to.
The priorities are labeled as CoS0 ~ CoS7.
Configuration Procedure:
Step Operation Description
1 Configure the mapping
QoS → DiffServ → DSCP Priority
page, relation between the DSCP priority and 802.1P priority enable DSCP Priority and configure the mapping relation between the DSCP priority and CoS.
2 Configure the mapping
QoS → DiffServ → 802.1P/CoS mapping
relation between the CoS and the TC page, configure the mapping relation between the CoS and the TC.
3 Select a schedule mode Required. On
QoS → DiffServ → Schedule Mode
page, select a schedule mode.
9.1.3 802.1P/CoS mapping
On this page you can configure the mapping relation between the 802.1P priority tag-id/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 → DiffServ → 802.1P/CoS mapping
to load the following page.
Figure 9-8 802.1P/CoS mapping
The following entries are displayed on this screen:
Priority and CoS-mapping Config
Tag-id/Cos-id:
Indicates the precedence level defined by IEEE802.1P and the
CoS ID.
117
Queue TC-id:
Indicates the priority level of egress queue the packets with tag and CoS-id are mapped to. The priority levels of egress queue are labeled as TC0, TC1, TC2 and TC3.
Configuration Procedure:
Step Operation Description
1 Configure the mapping
QoS → DiffServ → 802.1P/CoS mapping
relation between the 802.1P priority Tag/CoS and the TC page, configure the mapping relation between the
802.1P priority Tag/CoS and the TC.
2 Select a schedule mode Required. On
QoS → DiffServ → Schedule Mode
page,, select a schedule mode.
9.1.4 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… TC3.
Choose the menu
QoS → DiffServ → Schedule Mode
to load the following page.
Figure 9-9 Schedule Mode
The following entries are displayed on this screen:
Schedule Mode Config
SP-Mode:
WRR-Mode:
SP+WRR-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.
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 and TC3 is 1:2:4:8.
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, TC3 is in the SP group; TC0, TC1 and TC2 belong to the WRR group and the weight value ratio of
TC0, TC1 and TC2 is 1:2:4. In this way, when scheduling queues, the switch allows TC3 to occupy the whole bandwidth following the
SP mode and the TC0, TC1 and TC2 in the WRR group will take up the bandwidth according to their ratio 1:2:4.
118
Equ-Mode:
Equal-Mode. In this mode, all the queues occupy the bandwidth equally. The weight value ratio of all the queues is 1:1:1:1.
9.2 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.
9.2.1 Rate Limit
Rate limit functions to control the ingress/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 9-10 Rate Limit
The following entries are displayed on this screen:
Rate Limit Config
Port Select:
Select:
Port:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for Rate configuration. It is multi-optional.
Displays the port number of the switch.
119
Ingress Rate (bps):
Egress Rate(bps):
Configure the bandwidth for receiving packets on the port. You can select a rate from the dropdown list or select "Manual" to set
Ingress rate, the system will automatically select integral multiple of 64Kbps that closest to the rate you entered as the real Ingress rate.
Configure the bandwidth for sending packets on the port. You can select a rate from the dropdown list or select "Manual" to set
Egress rate, the system will automatically select integral multiple of 64Kbps that closest to the rate you entered as the real Egress rate.
Displays the LAG number which the port belongs to.
LAG:
Note:
1. If you enable ingress rate limit feature for the storm control-enabled port, storm control feature will be disabled for this port.
2. When selecting "Manual" to set Ingress/Egress rate, the system will automatically select integral multiple of 64Kbps that closest to the rate you entered as the real Ingress/Egress rate.
For example, if you enter 1000Kbps for egress rate, the system will automatically select
1024Kbps as the real Egress rate.
3. 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.
9.2.2 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.
120
Figure 9-11 Storm Control
The following entries are displayed on this screen:
Storm Control Config
Port Select:
Select:
Port:
Broadcast Rate
(bps):
Multicast Rate
(bps):
UL-Frame Rate
(bps):
LAG:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for Storm Control configuration. It is multi-optional.
Displays the port number of the switch.
Select the bandwidth for receiving broadcast packets on the port.
The packet traffic exceeding the bandwidth will be discarded.
Select Disable to disable the storm control function for the port.
Select the bandwidth for receiving multicast packets on the port.
The packet traffic exceeding the bandwidth will be discarded.
Select Disable to disable the storm control function for the port.
Select the bandwidth for receiving UL-Frame on the port. The packet traffic exceeding the bandwidth will be discarded. Select
Disable to disable the storm control function for the port.
Displays the LAG number which the port belongs to.
Note:
If you enable storm control feature for the ingress rate limit-enabled port, ingress rate limit feature will be disabled for this port.
121
9.3 Voice VLAN
Voice VLANs are configured specially for voice data stream. By configuring Voice VLANs and adding the ports with voice devices attached to voice VLANs, you can perform QoS-related configuration for voice data, ensuring the transmission priority of voice data stream and voice quality.
OUI Address (Organizationally unique identifier address)
The switch can determine whether a received packet is a voice packet by checking its source MAC address. If the source MAC address of packet complies with the OUI addresses configured by the system, the packet is determined as voice packets and transmitted in voice VLAN.
An OUI address is a unique identifier assigned by IEEE (Institute of Electrical and Electronics
Engineers) to a device vendor. It comprises the first 24 bits of a MAC address. You can recognize which vendor a device belongs to according to the OUI address. The following table shows the
OUI addresses of several manufacturers. The following OUI addresses are preset of the switch by default.
Number OUI Address Vendor
Table 9-1 OUI addresses on the switch
Port Voice VLAN Mode
A voice VLAN can operate in two modes: automatic mode and manual mode.
Automatic Mode: In this mode, the switch will automatically add a port which receives voice packets to voice VLAN and determine the priority of the packets through learning the source MAC of the UNTAG packets sent from IP phone when it is powered on. The aging time of voice VLAN can be configured on the switch. If the switch does not receive any voice packet on the ingress port within the aging time, the switch will remove this port from voice VLAN. Voice ports are automatically added into or removed from voice VLAN.
Manual Mode: You need to manually add the port of IP phone to voice VLAN, and then the switch will assign ACL rules and configure the priority of the packets through learning the source MAC address of packets and matching OUI address.
In practice, the port voice VLAN mode is configured according to the type of packets sent out from voice device and the link type of the port. The following table shows the detailed information.
122
Port Voice VLAN
Mode
Voice
Stream Type
Link type of the port and processing mode
Automatic Mode TAG voice stream
TRUNK: Supported. The default VLAN of the port can not be voice VLAN.
GENERAL: Supported. The default VLAN of the port can not be voice VLAN and the egress rule of the access port in the voice VLAN should be TAG.
UNTAG voice stream
ACCESS: Supported.
TRUNK: Not supported.
GENERAL: Supported. The default VLAN of the port should be voice VLAN and the egress rule of the access port in the voice VLAN should be UNTAG.
Manual Mode stream
TRUNK
：
Supported. The default VLAN of the port should not be voice VLAN.
GENERAL ： Supported. The default VLAN of the port can not be voice VLAN and the egress rule of the access port in the voice VLAN should be TAG.
UNTAG voice stream
ACCESS: Supported.
TRUNK: Not supported.
GENERAL: Supported. The default VLAN of the port should be voice VLAN and the egress rule of the access port in the voice VLAN should be UNTAG.
Table 9-2 Port voice VLAN mode and voice stream processing mode
Security Mode of Voice VLAN
When voice VLAN is enabled for a port, you can configure its security mode to filter data stream. If security mode is enabled, the port just forwards voice packets, and discards other packets whose source MAC addresses do not match OUI addresses. If security mode is not enabled, the port forwards all the packets.
Security
Mode
Packet Type
Enable
Disable
Processing Mode
UNTAG packet
Packet with voice
VLAN TAG
Packet with other
VLAN TAG
When the source MAC address of the packet is the OUI address that can be identified, the packet can be transmitted in the voice
VLAN. Otherwise, the packet will be discarded.
The processing mode for the device to deal with the packet is determined by whether the port permits the VLAN or not, independent of voice VLAN security mode.
UNTAG packet
Packet with voice
VLAN TAG
Do not check the source MAC address of the packet and all the packets can be transmitted in the voice VLAN.
Packet with other
VLAN TAG
The processing mode for the device to deal with the packet is determined by whether the port permits the VLAN or not, independent of voice VLAN security mode.
Table 9-3 Security mode and packets processing mode
123
Note:
Don’t transmit voice stream together with other business packets in the voice VLAN except for some special requirements.
The Voice VLAN function can be implemented on
Global Config, Port Config
and
OUI Config
pages.
9.3.1 Global Config
On this page, you can configure the global parameters of the voice VLAN, including VLAN ID, aging time, the transmission priority of the voice packets and so on.
Choose the menu
QoS → Voice VLAN → Global Config
to load the following page.
Figure 9-12 Global Config
The following entries are displayed on this screen:
Global Config
Voice VLAN:
VLAN ID:
Aging Time:
Priority:
Select Enable/Disable Voice VLAN function.
Enter the VLAN ID of the voice VLAN.
Specifies the living time of the member port in auto mode after the
OUI address is aging out.
Select the priority of the port when sending voice data. The default priority is 6.
9.3.2 Port Config
Before the voice VLAN function is enabled, the parameters of the ports in the voice VLAN should be configured on this page.
Choose the menu
QoS → Voice VLAN → Port Config
to load the following page.
124
Figure 9-13 Port Config
Note:
To enable voice VLAN function for the LAG member port, please ensure its member state accords with its port mode.
If a port is a member port of voice VLAN, changing its port mode to be “Auto” will make the port leave the voice VLAN and will not join the voice VLAN automatically until it receives voice streams.
The following entries are displayed on this screen:
Port Config
Port Select:
Select:
Port:
Port Mode:
Security Mode:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select the desired port for voice VLAN configuration. It is multi-optional.
Displays the port number of the switch.
Select the mode for the port to join the voice VLAN.
Auto: In this mode, the switch automatically adds a port to the voice VLAN or removes a port from the voice VLAN by checking whether the port receives voice data or not
Manual: In this mode, you can manually add a port to the voice VLAN or remove a port from the voice VLAN.
Configure the security mode for forwarding packets.
Disable: All packets are forwarded.
Enable: Only voice data are forwarded.
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Member State:
LAG:
Displays the state of the port in the current voice VLAN.
Displays the LAG number which the port belongs to.
9.3.3 OUI Config
The switch supports OUI creation and adds the MAC address of the special voice device to the
OUI table of the switch. The switch determines whether a received packet is a voice packet by checking its OUI address. The switch analyzes the received packets. If the packets are recognized as voice packets, the access port will be automatically added to the Voice VLAN.
Choose the menu
QoS → Voice VLAN → OUI Config
to load the following page.
Figure 9-14 OUI Config
The following entries are displayed on this screen:
Create OUI
OUI:
Mask:
Description:
Enter the OUI address of the voice device.
Enter the OUI address mask of the voice device.
Give a description to the OUI for identification.
OUI Table
Select:
OUI:
Mask:
Description:
Select the desired entry to view the detailed information.
Displays the OUI address of the voice device.
Displays the OUI address mask of the voice device.
Displays the description of the OUI.
Configuration Procedure of Voice VLAN:
126
Step Operation Description
1 Configure the link Required. On
VLAN → 802.1Q VLAN → Port Config
page, type of the port configure the link type of ports of the voice device.
2
3
Create VLAN
Add OUI address
Required. On
VLAN → 802.1Q VLAN → Port Config
page,, click the
Create
button to create a VLAN.
Optional. On
QoS → Voice VLAN → OUI Config
page, you can check whether the switch is supporting the OUI template or not. If not, please add the OUI address.
4 Configure the parameters of the ports in voice VLAN.
QoS → Voice VLAN → Port Config
the parameters of the ports in voice VLAN.
page, configure
5
Enable Voice VLAN
Required. On
QoS → Voice VLAN → Global Config
page, configure the global parameters of voice VLAN.
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Chapter 10 ACL
ACL (Access Control List) is used to filter packets by configuring match rules and process policies of packets in order to control the access of the illegal users to the network. Besides, ACL functions to control traffic flows and save network resources. It provides a flexible and secured access control policy and facilitates you to control the network security.
On this switch, ACLs classify packets based on a series of match conditions, which can be L2-L4 protocol key fields carried in the packets. A time-range based ACL enables you to implement ACL control over packets by differentiating the time-ranges.
The ACL module is mainly for ACL configuration of the switch, including four submenus:
Time-Range
,
ACL Config, Policy Config
and
Policy Binding
.
10.1 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, week time and holiday 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 week time section to make ACLs effective on the fixed days of the week; configure a holiday section to make
ACLs effective on some special days. In each time-range, four time-slices can be configured.
The Time-Range configuration can be implemented on
Time-Range Summary
,
Time-Range
Create
and
Holiday Config
pages.
10.1.1 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 10-1 Time-Range Table
The following entries are displayed on this screen:
Time-Range Table
Select:
Index:
Select the desired entry to delete the corresponding time-range.
Displays the index of the time-range.
Time-Range Name:
Displays the name of the time-range.
Slice:
Displays the time-slice of the time-range.
Mode:
Detail:
Displays the mode the time-range adopts.
Click the
Detail
button to display the complete information of this time–range.
128
10.1.2 Time-Range Create
On this page you can create time-ranges.
Choose the menu
ACL → Time-Range → Time-Range Create
to load the following page.
Figure 10-2 Time-Range Create
Note:
To successfully configure time-ranges, please firstly specify time-slices and then time-ranges.
The following entries are displayed on this screen:
Create Time-Range
Name:
Holiday:
Absolute:
Week:
Enter the name of the time-range for time identification.
Select Holiday you set as a time-range. The ACL rule based on this time-range takes effect only when the system time is within the holiday.
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.
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.
Create Time-Slice
Start Time:
End Time:
Time-Slice Table
Index:
Start Time:
Set the start time of the time-slice.
Set the end time of the time-slice.
Displays the index of the time-slice.
Displays the start time of the time-slice.
129
End Time:
Delete:
Displays the end time of the time-slice.
Click the
Delete
button to delete the corresponding time-slice.
10.1.3 Holiday Config
Holiday mode is applied as a different secured access control policy from the week mode. On this page you can define holidays according to your work arrangement.
Choose the menu
ACL → Time-Range → Holiday Config
to load the following page.
Figure 10-3 Holiday Configuration
The following entries are displayed on this screen:
Create Holiday
Start Date:
End Date:
Holiday Name:
Specify the start date of the holiday.
Specify the end date of the holiday.
Enter the name of the holiday.
Holiday Table
Select:
Index:
Holiday Name:
Start Date:
End Date:
Select the desired entry to delete the corresponding holiday.
Displays the index of the holiday.
Displays the name of the holiday.
Displays the start date of the holiday.
Displays the end date of the holiday.
10.2 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.
The ACL Config function can be implemented on
ACL Summary
,
ACL Create
,
MAC ACL
,
Standard-IP ACL
and
Extend-IP ACL
pages.
130
10.2.1 ACL Summary
On this page, you can view the current ACLs configured in the switch.
Choose the menu
ACL → ACL Config → ACL Summary
to load the following page.
Figure 10-4 ACL Summary
The following entries are displayed on this screen:
Search Option
Select ACL:
ACL Type:
Rule Order:
Select the ACL you have created
Displays the type of the ACL you select.
Displays the rule order of the ACL you select.
Rule Table
Here you can view the information about the ACL rule you select.
10.2.2 ACL Create
On this page you can create ACLs.
Choose the menu
ACL → ACL Config → ACL Create
to load the following page.
Figure 10-5 ACL Create
The following entries are displayed on this screen:
Create ACL
ACL ID:
Rule Order:
Enter ACL ID of the ACL you want to create.
User Config order is set to be match order in this ACL.
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10.2.3 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, VLAN ID, and EtherType carried in the packets.
Choose the menu
ACL → ACL Config → MAC ACL
to load the following page.
Figure10-6 Create MAC Rule
The following entries are displayed on this screen:
Create MAC ACL
ACL ID:
Rule ID:
Operation:
S-MAC:
D-MAC:
MASK:
VLAN ID:
EtherType:
User Priority:
Time-Range:
Select the desired MAC ACL for configuration.
Enter the rule ID.
Select the operation for the switch to process packets which match the rules.
Permit: Forward packets.
Deny: Discard Packets.
Enter the source MAC address contained in the rule.
Enter the destination MAC address contained in the rule.
Enter MAC address mask. If it is set to 1, it must strictly match the address.
Enter the VLAN ID contained in the rule.
Enter EtherType contained in the rule.
Select the user priority contained in the rule for the tagged packets to match.
Select the time-range for the rule to take effect.
132
10.2.4 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.
Figure10-7 Create Standard-IP Rule
The following entries are displayed on this screen:
Create Standard-IP ACL
ACL ID:
Rule ID:
Operation:
S-IP:
D-IP:
Mask:
Time-Range:
Select the desired Standard-IP ACL for configuration.
Enter the rule ID.
Select the operation for the switch to process packets which match the rules.
Permit: Forward packets.
Deny: Discard Packets.
Enter the source IP address contained in the rule.
Enter the destination IP address contained in the rule.
Enter IP address mask. If it is set to 1, it must strictly match the address.
Select the time-range for the rule to take effect.
10.2.5 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.
Choose the menu
ACL → ACL Config → Extend-IP ACL
to load the following page.
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Figure10-8 Create Extend-IP Rule
The following entries are displayed on this screen:
Create Extend-IP ACL
ACL ID:
Rule ID:
Operation:
S-IP:
D-IP:
Mask:
IP Protocol:
TCP Flag
：
S-Port:
D-Port:
DSCP:
IP ToS:
Select the desired Extend-IP ACL for configuration.
Enter the rule ID.
Select the operation for the switch to process packets which match the rules.
Permit: Forward packets.
Deny: Discard Packets.
Enter the source IP address contained in the rule.
Enter the destination IP address contained in the rule.
Enter IP address mask. If it is set to 1, it must strictly match the address.
Select IP protocol contained in the rule.
Configure TCP flag when TCP is selected from the pull-down list of IP
Protocol.
Configure TCP/IP source port contained in the rule when TCP/UDP is selected from the pull-down list of IP Protocol.
Configure TCP/IP destination port contained in the rule when
TCP/UDP is selected from the pull-down list of IP Protocol.
Enter the DSCP information contained in the rule.
Enter the IP-ToS contained in the rule.
134
IP Pre:
Time-Range:
Enter the IP Precedence contained in the rule.
Select the time-range for the rule to take effect.
10.3 Policy Config
A Policy is used to control the data packets those match the corresponding ACL rules by configuring ACLs and actions together for effect. The operations here include stream mirror, stream condition, QoS remarking and redirect.
The Policy Config can be implemented on
Policy Summary
,
Police Create
and
Action Create
pages.
10.3.1 Policy Summary
On this page, you can view the ACL and the corresponding operations in the policy.
Choose the menu
ACL → Policy Config → Policy Summary
to load the following page.
Figure 10-9 Policy Summary
The following entries are displayed on this screen:
Search Option
Select Policy:
Select name of the desired policy for view. If you want to delete the desired policy, please click the
Delete
button.
Action Table
Select:
Index:
ACL ID:
S-Mirror:
S-Condition:
Redirect:
QoS Remark:
Select the desired entry to delete the corresponding policy.
Enter the index of the policy.
Displays the ID of the ACL contained in the policy.
Displays the source mirror port of the policy.
Displays the source condition added to the policy.
Displays the redirect added to the policy.
Displays the QoS remark added to the policy.
10.3.2 Policy Create
On this page you can create the policy.
Choose the menu
ACL → Policy Config → Policy Create
to load the following page.
135
Figure 10-10 Create Policy
The following entries are displayed on this screen:
Create Policy
Policy Name:
Enter the name of the policy.
10.3.3 Action Create
On this page you can add ACLs and create corresponding actions for the policy.
Choose the menu
ACL → Policy Config → Action Create
to load the following page.
Figure 10-11 Action Create
The following entries are displayed on this screen:
Create Action
Select Policy:
Select ACL:
S-Mirror:
Select the name of the policy.
Select the ACL for configuration in the policy.
Select S-Mirror to mirror the data packets in the policy to the specific port.
136
S-Condition:
Redirect:
QoS Remark:
Select S-Condition to limit the transmission rate of the data packets in the policy.
Rate: Specify the forwarding rate of the data packets those match the corresponding ACL.
Out of Band: Specify the disposal way of the data packets those are transmitted beyond the rate.
Select Redirect to change the forwarding direction of the data packets in the policy.
Destination Port: Forward the data packets those match the corresponding ACL to the specific port.
Select QoS Remark to forward the data packets based on the QoS settings.
DSCP: Specify the DSCP region for the data packets those match the corresponding ACL.
Local Priority: Specify the local priority for the data packets those match the corresponding ACL.
10.4 Policy Binding
Policy Binding function can have the policy take its effect on a specific port/VLAN. The policy 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 policy only when the policy is bound to the port/VLAN.
The Policy Binding can be implemented on
Binding Table
,
Port Binding
and
VLAN Binding
pages.
10.4.1 Binding Table
On this page view the policy bound to port/VLAN.
Choose the menu
ACL → Policy Binding → Binding Table
to load the following page.
Figure 10-12 Binding Table
The following entries are displayed on this screen:
Search Option
Select a show mode appropriate to your needs.
Show Mode:
Policy Bind Table
Select:
Select the desired entry to delete the corresponding binding policy.
137
Index:
Policy Name:
Interface:
Direction:
Displays the index of the binding policy.
Displays the name of the binding policy.
Displays the port number or VLAN ID bound to the policy.
Displays the binding direction.
10.4.2 Port Binding
On this page you can bind a policy to a port.
Choose the menu
ACL → Policy Binding → Port Binding
to load the following page.
Figure 10-13 Bind the policy to the port
The following entries are displayed on this screen:
Port-Bind Config
Policy Name:
Port:
Select the name of the policy you want to bind.
Enter the number of the port you want to bind.
Port-Bind Table
Index:
Policy Name:
Port:
Direction:
Displays the index of the binding policy.
Displays the name of the binding policy.
Displays the number of the port bound to the corresponding policy.
Displays the binding direction.
10.4.3 VLAN Binding
On this page you can bind a policy to a VLAN.
Choose the menu
ACL → Policy Binding → VLAN Binding
to load the following page.
138
Figure10-14 Bind the policy to the VLAN
The following entries are displayed on this screen:
VLAN-Bind Config
Policy Name:
VLAN ID:
VLAN-Bind Table
Index:
Policy Name:
VLAN ID:
Direction:
Select the name of the policy you want to bind.
Enter the ID of the VLAN you want to bind.
Displays the index of the binding policy.
Displays the name of the binding policy.
Displays the ID of the VLAN bound to the corresponding policy.
Displays the binding direction.
Configuration Procedure:
Step Operation
1 Configure time-range
Description
effective Required. On
ACL → Time-Range
configuration pages, configure the effective time-ranges for ACLs.
Required. On
ACL → ACL Config
configuration pages, configure ACL rules to match packets.
Required. On
ACL → Policy Config
configuration pages, configure the policy to control the data packets those match the corresponding ACL rules.
4 Bind the policy to the Required. On
ACL → Policy Binding
configuration pages, port/VLAN bind the policy to the port/VLAN to make the policy effective on the corresponding port/VLAN.
10.5 Application Example for ACL
Network Requirements
1. The manager of the R&D department can access to the forum of the company and the Internet without any forbiddance. The MAC address of the manager is 00-46-A5-5D-12-C3.
2. The staff of the R&D department can not access to the Internet during the working time but can visit the forum all day.
139
3. The staff of the marketing department can access to the Internet all day but can not visit the forum during the working time.
4. The R&D department and marketing department can not communicate with each other.
Network Diagram
Configuration Procedure
Step Operation
1 Configure
Time-range
Description
On
ACL → Time-Range
page, create a time-range named work_time.
Select Week mode and configure the week time from Monday to Friday.
Add a time-slice 08:00~18:00.
2 Configure requirement 1
On
On
ACL
ACL
→
→
ACL Config
ACL Config
→
→
ACL Create
MAC ACL
page, create ACL 11. page, select ACL 11, create Rule 1, configure the operation as Permit, configure the S-MAC as
00-46-A5-5D-12-C3 and mask as FF-FF-FF-FF-FF-FF, and configure the time-range as No Limit.
On
ACL → Policy Config → Policy Create
page, create a policy named manager.
On
ACL → Policy Config → Action Create
page, add ACL 11 to Policy manager.
On
ACL → Policy Binding → Port Binding
page, select Policy manager to bind to port 3.
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Step Operation Description
and 4
On requirement 2
ACL → ACL Config → ACL Create
page, create ACL 100.
On
ACL → ACL Config → Standard-IP ACL
page, select ACL 100, create Rule 1, configure operation as Deny, configure S-IP as
10.10.70.1 and mask as 255.255.255.0, configure D-IP as 10.10.50.1 and mask as 255.255.255.0, configure the time-range as No Limit.
On
ACL → ACL Config → Standard-IP ACL
page, select ACL 100, create Rule 2, configure operation as Deny, configure S-IP as
10.10.70.1 and mask as 255.255.255.0, configure D-IP as 10.10.88.5 and mask as 255.255.255.255, configure the time-range as No Limit.
On
ACL → ACL Config → Standard-IP ACL
page, select ACL 100, create Rule 3, configure operation as Permit, configure S-IP as
10.10.70.1 and mask as 255.255.255.0, configure D-IP as 10.10.88.5 and mask as 255.255.255.0, configure the time-range as work_time.
On
ACL → Policy Config → Policy Create
page, create a policy named limit1.
On
ACL → Policy Config → Action Create
page, add ACL 100 to Policy limit1.
On
ACL → Policy Binding → Port Binding
page, select Policy limit1 to bind to port 3. for requirement 3 and 4
ACL → ACL Config → ACL Create
page, create ACL 101.
On
ACL → ACL Config → Standard-IP ACL
page, select ACL 101, create Rule 4, configure operation as Deny, configure S-IP as
10.10.70.1 and mask as 255.255.255.0, configure D-IP as 10.10.50.1 and mask as 255.255.255.0, configure the time-range as No Limit.
On
ACL → ACL Config → Standard-IP ACL
page, select ACL 101, create Rule 5, configure operation as Deny, configure S-IP as
10.10.70.1 and mask as 255.255.255.0, configure D-IP as 10.10.88.5 and mask as 255.255.255.255, configure the time-range as No Limit.
On
ACL → Policy Config → Policy Create
page, create a policy named limit2.
On
ACL → Policy Config → Action Create
page, add ACL 101 to Policy limit2.
On
ACL → Policy Binding → Port Binding
page, select Policy limit2 to bind to port 4.
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Chapter 11 Network Security
Network Security module is to provide the multiple protection measures for the network security, including four submenus:
IP-MAC Binding
,
ARP Inspection
,
DoS Defend
and
802.1X
. Please configure the functions appropriate to your need.
11.1 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. Based on the IP-MAC binding table and ARP
Inspection functions, you can control the network access and only allow the Hosts matching the bound entries to access the network.
The following three 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
）
Scanning: You can quickly get the information of the IP address, MAC address, VLAN ID and the connected port number of the Hosts in the LAN via the ARP Scanning function, and bind them conveniently. You are only requested to enter the range of the IP address on the ARP Scanning page for the scanning.
（ 3 ） 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.
These three methods are also considered as the sources of the IP-MAC Binding entries. The entries from various sources should be different from one another to avoid collision. Among the entries in collision, only the entry from the source with the highest priority will take effect. These three sources (Manual, Scanning and Snooping) are in descending order of priority.
The
IP-MAC Binding
function is implemented on the
Binding Table
,
Manual Binding
,
ARP
Scanning
and
DHCP Snooping
pages.
11.1.1 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 11-1 Binding Table
142
The following entries are displayed on this screen:
Search Option
Source:
Select a Source from the pull-down list and click the
Search
button to view your desired entry in the Binding Table.
All:
All the bound entries will be displayed.
Manual:
Only the manually added entries will be displayed.
Scanning:
Only the entries formed via ARP Scanning will be displayed.
Snooping:
Only the entries formed via DHCP Snooping will be displayed.
Binding Table
IP Select:
Select:
Host Name:
IP Address:
MAC Address:
VLAN ID:
Port:
Protect Type:
Source:
Collision:
Click the
Select
button to quick-select the corresponding entry based on the IP address you entered.
Select the desired entry to modify the Host Name and Protect
Type. It is multi-optional.
Displays the Host Name here.
Displays the IP Address of the Host.
Displays the MAC Address of the Host.
Displays the VLAN ID here.
Displays the number of port connected to the Host.
Allows you to view and modify the Protect Type of the entry.
Displays the Source of the entry.
Displays the Collision status of the entry.
Warning:
Indicates that the collision may be caused by the
MSTP function.
Critical:
Indicates that the entry has a collision with the other entries.
Note:
1 Among the entries with Critical collision level, the one with the highest Source priority will take effect.
2 Among the conflicting entries with the same Source priority, only the last added or edited one will take effect.
11.1.2 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.
Choose the menu
Network Security → IP-MAC Binding → Manual Binding
to load the following page.
143
Figure 11-2 Manual Binding
The following entries are displayed on this screen:
Manual Binding Option
Host Name:
IP Address:
MAC Address:
VLAN ID:
Port:
Protect Type:
Manual Binding Table
Select:
Host Name:
IP Address:
MAC Address:
VLAN ID:
Port:
Protect Type:
Collision:
Enter the Host Name.
Enter the IP Address of the Host.
Enter the MAC Address of the Host.
Enter the VLAN ID.
Select the number of port connected to the Host.
Select the Protect Type for the entry.
Select the desired entry to be deleted. It is multi-optional.
Displays the Host Name here.
Displays the IP Address of the Host.
Displays the MAC Address of the Host.
Displays the VLAN ID here.
Displays the number of port connected to the Host.
Displays the Protect Type of the entry.
Displays the Collision status of the entry.
Warning:
Indicates that the collision may be caused by the MSTP function.
Critical:
Indicates that the entry has a collision with the other entries.
144
11.1.3 ARP Scanning
ARP (Address Resolution Protocol) is used to analyze and map IP addresses to the corresponding
MAC addresses so that packets can be delivered to their destinations correctly. IP address is the address of the Host on Network layer. MAC address, the address of the Host on Data link layer, is necessary for the packet to reach the very device. So the destination IP address carried in a packet need to be translated into the corresponding MAC address.
ARP functions to translate the IP address into the corresponding MAC address and maintain an
ARP Table, where the latest used IP address-to-MAC address mapping entries are stored. When the Host communicates with a strange Host, ARP works as the following figure shown.
Figure 11-3 ARP Implementation Procedure
（ 1 ） Suppose there are two hosts in the LAN: Host A and Host B. To send a packet to Host B,
Host A checks its own ARP Table first to see if the ARP entry related to the IP address of Host
B exists. If yes, Host A will directly send the packets to Host B. If the corresponding MAC address is not found in the ARP Table, Host A will broadcast ARP request packet, which contains the IP address of Host B, the IP address of Host A, and the MAC address of Host A, in the LAN.
（ 2 ） Since the ARP request packet is broadcasted, all hosts in the LAN can receive it. However, only the Host B recognizes and responds to the request. Host B sends back an ARP reply packet to Host A, with its MAC address carried in the packet.
（
3
）
Upon receiving the ARP reply packet, Host A adds the IP address and the corresponding
MAC address of Host B to its ARP Table for the further packets forwarding.
ARP Scanning function enables the switch to send the ARP request packets of the specified IP field to the Hosts in the LAN or VLAN. Upon receiving the ARP reply packet, the switch can get the
IP address, MAC address, VLAN and the connected port number of the Host by analyzing the packet and bind them conveniently.
Choose the menu
Network Security → IP-MAC Binding → ARP Scanning
to load the following page.
145
Figure 11-4 ARP Scanning
The following entries are displayed on this screen:
Scanning Option
Start IP Address:
End IP Address:
VLAN ID:
Scan:
Specify the Start IP Address.
Specify the End IP Address.
Enter the VLAN ID. If blank, the switch will send the untagged packets for scanning.
Click the
Scan
button to scan the Hosts in the LAN.
Scanning Result
Select:
Host Name:
IP Address:
MAC Address:
VLAN ID:
Port:
Protect Type:
Collision:
Select the desired entry to be bound or deleted.
Displays the Host Name here.
Displays the IP Address of the Host.
Displays the MAC Address of the Host.
Displays the VLAN ID here.
Displays the number of port connected to the Host.
Displays the Protect Type of the entry.
Displays the Collision status of the entry.
Warning:
Indicates that the collision may be caused by the
MSTP function.
Critical:
Indicates that the entry has a collision with the other entries.
11.1.4 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
146
network configuration protocol optimized and developed based 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 address for several Clients, which is illustrated in the following figure.
Figure 11-5 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.
147
Figure 11-6 Interaction between a DHCP client and a DHCP server
（
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 based 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.
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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.
（ 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 11-7 DHCP Cheating Attack Implementation Procedure
DHCP Snooping feature only allows the port connected to the DHCP Server as the trusted port to forward 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 and the other security protection features.
DHCP Snooping feature prevents the network from the DHCP Server Cheating Attack by discarding the DHCP packets on the distrusted port, so as to enhance the network security.
149
Choose the menu
Network Security → IP-MAC Binding → DHCP Snooping
to load the following page.
Figure 11-8 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.
The following entries are displayed on this screen:
DHCP Snooping Config
150
DHCP Snooping:
Global Flow Control:
Decline Threshold:
Decline Flow Control:
Enable/Disable the DHCP Snooping function globally.
Select the value to specify the maximum amount of DHCP messages that can be forwarded by the switch per second. The excessive massages will be discarded.
Select the value to specify the minimum transmission rate of the
Decline packets to trigger the Decline protection for the specific port.
Select the value to specify the Decline Flow Control. The traffic flow of the corresponding port will be limited to be this value if the transmission rate of the Decline packets exceeds the
Decline Threshold.
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 replace the Option 82 field of the packets with the switch defined one.
Drop:
Indicates to discard the packets including the Option
82 field.
Customization:
Circuit ID:
Remote ID:
Enable/Disable the switch to define the Option 82.
Enter the sub-option Circuit ID for the customized Option 82.
Enter the sub-option Remote ID for the customized Option 82.
Port Config
Port Select:
Select:
Port:
Trusted Port:
MAC Verify:
Flow Control:
Decline Protect:
LAG:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select your desired port for configuration. It is multi-optional.
Displays the port number.
Select Enable/Disable the port to be a Trusted Port. Only the
Trusted Port can receive the DHCP packets from DHCP servers.
Select Enable/Disable the MAC Verify feature. There are two fields of the DHCP packet containing the MAC address of the
Host. The MAC Verify feature is to compare the two fields and discard the packet if the two fields are different.
Select Enable/Disable the Flow Control feature for the DHCP packets. The excessive DHCP packets will be discarded.
Select Enable/Disable the Decline Protect feature.
Displays the LAG to which the port belongs to.
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11.2 ARP Inspection
According to the ARP Implementation Procedure stated in 11.1.3 ARP Scanning, it can be found
that ARP protocol can facilitate the Hosts in the same network segment to communicate with one another or access to external network via Gateway. However, 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 can not access the network normally. The ARP Attack implemented by imitating Gateway is illustrated in the following figure.
Figure 11-9 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 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 can not communicate with the legal terminal Hosts normally. The ARP Attack implemented by cheating Gateway is illustrated in the following figure.
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Figure 11-10 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 can not communicate with each other normally. The ARP Attack implemented by cheating terminal
Hosts is illustrated in the following figure.
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Figure 11-11 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.
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Figure 11-12 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.
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. 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 can not access the external network.
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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. Based 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.
11.2.1 ARP Detect
ARP Detect feature enables the switch to detect the ARP packets based 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.
Choose the menu
Network Security → ARP Inspection → ARP Detect
to load the following page.
Figure 11-13 ARP Detect
The following entries are displayed on this screen:
ARP Detect
ARP Detect:
Enable/Disable the ARP Detect function, and click the
Apply
button to apply.
Trusted Port
Trusted Port:
Select the port for which the ARP Detect function is unnecessary as the Trusted Port . The specific ports, such as up-linked port, routing port and LAG port, should be set as Trusted Port. To ensure the normal communication of the switch, please configure the ARP Trusted Port before enabling the ARP Detect function.
Note:
ARP Detect and ARP Defend cannot be enabled at the same time.
156
Configuration Procedure:
Step Operation Description
1 Bind the IP address, MAC address, VLAN ID and the connected Port number of the Host together.
Required. On the
IP-MAC Binding
page, bind the IP address, MAC address, VLAN ID and the connected Port number of the Host together via Manual Binding, ARP
Scanning or DHCP Snooping.
2 Enable the protection for the bound entry.
Required. On the
Network Security → IP-MAC
Binding → Binding Table
page, specify a protect type for the corresponding bound entry.
3 Specify the trusted port. Required. On the
Network Security → ARP
Inspection → ARP Detect
page, specify the trusted port.
The specific ports, such as up-linked port, routing port and LAG port, should be set as Trusted Port.
4 Enable ARP Detect feature. Required. On the
Network Security → ARP
Inspection → ARP Detect
page, enable the ARP Detect feature.
11.2.2 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 11-14 ARP Defend
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The following entries are displayed on this screen:
ARP Defend
Port Select:
Select:
Port:
Defend:
Speed:
Current Speed:
Status:
LAG:
Operation:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select your desired port for configuration. It is multi-optional.
Displays the port number.
Select Enable/Disable the ARP Defend feature for the port.
Enter a value to specify the maximum amount of the received ARP packets per second.
Displays the current speed of the received ARP packets.
Displays the status of the ARP attack.
Displays the LAG to which the port belongs to.
Click the
Recover
button to restore the port to the normal status.
The ARP Defend for this port will be re-enabled.
Note:
1. It’s not recommended to enable the ARP Defend feature for the LAG member port.
2. ARP Detect and ARP Defend cannot be enabled at the same time.
11.2.3 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.
158
Figure 11-15 ARP Statistics
The following entries are displayed on this screen:
Auto Refresh
Auto Refresh:
Refresh Interval:
Illegal ARP Packet
Port:
Trusted Port:
Illegal ARP Packet:
Enable/Disable the Auto Refresh feature.
Specify the refresh interval to display the ARP Statistics.
Displays the port number.
Indicates the port is an ARP Trusted Port or not.
Displays the number of the received illegal ARP packets.
11.3 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 a few types of DoS attack listed in the following table.
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DoS Attack Type
Land Attack
Scan SYNFIN
Description
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.
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
NULL Scan Attack
The attacker sends the illegal packet with its TCP index, FIN, URG and
PSH field set to 1.
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 Land
Attack, the system performance of the attacked Host is reduced since the
Host circularly attempts to build a connection with the attacker.
Ping Flooding
SYN/SYN-ACK Flooding
The attacker floods the destination system with Ping broadcast storm packets to forbid the system to respond to the legal communication.
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 11-1 Defendable DoS Attack Types
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.
160
Figure 11-16 DoS Defend
The following entries are displayed on this screen:
Configure
DoS Defend:
Enable/Disable DoS Defend function.
Defend Table
Select:
Defend Type:
Select the entry to enable the corresponding Defend Type.
Displays the Defend Type name.
Tips:
You are suggested to take the following further steps to ensure the network security.
1. It’s recommended to inspect and repair the system vulnerability regularly. It is also necessary to install the system bulletins and backup the important information in time.
2. The network administrator is suggested to inspect the physic environment of the network and block the unnecessary network services.
3. Enhance the network security via the protection devices, such as the hardware firewall.
11.4 802.1X
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 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.
161
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 11-17 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 controlled port according to the instructions (accept or reject) received from the RADIUS server.
162
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 11-18 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.
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.
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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 can not 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.
Figure 11-19 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
164
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
,
Port Config
and
Radius Server
pages.
11.4.1 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.
165
Figure 11-20 Global Config
The following entries are displayed on this screen:
Global Config
802.1X:
Authentication Method:
Guest VLAN:
Guest VLAN ID:
Enable/Disable the 802.1X function.
Select the Authentication Method from the pull-down list.
EAP-MD5:
IEEE 802.1X authentication system uses extensible authentication protocol (EAP) to exchange information between the switch and the
authentication data can be encapsulated in the advanced protocol (such as RADIUS) packets to be transmitted to the authentication server.
PAP:
IEEE 802.1X authentication system uses extensible authentication protocol (EAP) to exchange information between the switch and the client. The transmission of EAP packets is terminated at the switch and the EAP packets are converted to the other protocol (such as RADIUS) packets for transmission.
Enable/Disable the Guest VLAN feature.
Enter your desired VLAN ID to enable the Guest VLAN feature. The supplicants in the Guest VLAN can access the specified network source.
Authentication Config
Quiet:
Quiet Period:
Enable/Disable the Quiet timer.
Specify a value for Quiet Period. Once the supplicant failed to the 802.1X Authentication, then the switch will not
166
Retry Times:
Supplicant Timeout:
Server Timeout:
respond to the authentication request from the same supplicant during the Quiet Period.
Specify the maximum transfer times of the repeated authentication request.
Specify the maximum time for the switch to wait for the response from supplicant before resending a request to the supplicant.
Specify the maximum time for the switch to wait for the response from authentication server before resending a request to the authentication server.
11.4.2 Port Config
On this page, you can configure the 802.1X features for the ports based on the actual network.
Choose the menu
Network Security → 802.1X
→ Port Config
to load the following page.
Figure 11-21 Port Config
The following entries are displayed on this screen:
Port Config
Port Select:
Select:
Port:
Status:
Click the
Select
button to quick-select the corresponding port based on the port number you entered.
Select your desired port for configuration. It is multi-optional.
Displays the port number.
Select Enable/Disable the 802.1X authentication feature for the
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Guest VLAN:
Control Mode:
Control Type:
port.
Select Enable/Disable the Guest VLAN feature for the port.
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.
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.
Displays the authentication status of the port.
Displays the LAG to which the port belongs to.
Authorized:
LAG:
11.4.3 Radius Server
RADIUS (Remote Authentication Dial-In User Service) server provides the authentication service for the switch via the stored client information, such as the user name, password, etc, with the purpose to control the authentication and accounting status of the clients. On this page, you can configure the parameters of the authentication server.
Choose the menu
Network Security → 802.1X
→ Radius Server
to load the following page.
Figure 11-22 Radius Server
The following entries are displayed on this screen:
Authentication Config
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Primary IP:
Secondary IP:
Authentication Port:
Authentication KEY:
Enter the IP address of the authentication server.
Enter the IP address of the alternate authentication server.
Set the UDP port of authentication server(s). The default port is 1812
Set the shared password for the switch and the authentication servers to exchange messages.
Accounting Config
Accounting:
Primary IP:
Secondary IP:
Accounting Port:
Accounting Key:
Enable/Disable the accounting feature.
Enter the IP address of the accounting server.
Enter the IP address of the alternate accounting server.
Set the UDP port of accounting server(s). The default port is 1813.
Set the shared password for the switch and the accounting servers to exchange messages.
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 can not be enabled for LAG member ports. That is, the port with 802.1X function enabled can not 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 Required. For the client computers, you are required to software. install the 802.1X software TpSupplicant provided on the
CD. For the installation guide, please refer to
globally. On the
Network Security → 802.1X
→ Global Config
page, configure the 802.1X function globally.
4 Configure the parameters of the authentication server
Required. On the
Network Security → 802.1X
→ Radius
Server
page, configure the parameters of the server.
5 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 based on the actual network.
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Chapter 12 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 based 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.
Figure 12-1 Relationship among SNMP Network Elements
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 can not communicate with each other normally. You can select the management mode with proper security level according to your actual application requirement.
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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:
Based 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}.
Figure 12-2 Architecture of the MIB tree
SNMP Configuration Outline
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
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
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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
.
12.1 SNMP Config
The
SNMP Config
can be implemented on the
Global Config
,
SNMP View
,
SNMP Group
,
SNMP User
and
SNMP Community
pages.
12.1.1 Global Config
To enable SNMP function, please configure the SNMP function globally on this page.
Choose the menu
SNMP → SNMP Config → Global Config
to load the following page.
Figure 12-3 Global Config
The following entries are displayed on this screen:
Global Config
SNMP:
Enable/Disable the SNMP function.
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.
Remote Engine
Remote Engine ID:
Specify the Remote Engine ID for switch. The Engine ID is a unique alphanumeric string used to identify the SNMP engine on the remote device which receives traps and informs from switch.
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Note:
The amount of Engine ID characters must be even.
12.1.2 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.
Figure 12-4 SNMP View
The following entries are displayed on this screen:
View Config
View Name:
MIB Object ID:
View Type:
Give a name to the View for identification. Each View can include several entries with the same name.
Enter the Object Identifier (OID) for the entry of View.
Select the type for the view entry.
Include: The view entry can be managed by the SNMP management station.
Exclude: The view entry can not be managed by the SNMP management station.
View Table
Select:
View Name:
View Type:
MIB Object ID:
Select the desired entry to delete the corresponding view. All the entries of a View will be deleted together.
Displays the name of the View entry.
Displays the type of the View entry.
Displays the OID of the View entry.
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12.1.3 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.
Figure 12-5 SNMP Group
The following entries are displayed on this screen:
Group Config
Group Name:
Security Model:
Security Level:
Read View:
Enter the SNMP Group name. 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.
Select the Security Model for the SNMP Group.
v1:
Community Name is used for authentication. SNMP v1 can be configured on the SNMP Community page directly.
v2c:
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.
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.
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.
174
Write View:
Notify 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.
Select the View to be the Notify View. The management station can receive trap messages of the assigned SNMP view generated by the switch's SNMP agent.
Group Table
Select:
Group Name:
Security Model:
Security Level:
Read View:
Write View:
Notify View:
Operation:
Select the desired entry to delete the corresponding group. It is multi-optional.
Displays the Group Name here.
Displays the Security Model of the group.
Displays the Security Level of the group.
Displays the Read View name in the entry.
Displays the Write View name in the entry.
Displays the Notify View name in the entry.
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 viewDefault.
12.1.4 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.
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Figure 12-6 SNMP User
The following entries are displayed on this screen:
User Config
User Name:
User Type:
Group Name:
Security Model:
Security Level:
Auth Mode:
Auth Password:
Privacy Mode:
Privacy Password:
Enter the User Name here.
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.
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.
Select the Security Model for the User.
Select the Security Level for the SNMP v3 User.
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.
Enter the password for authentication.
Select the Privacy Mode for the SNMP v3 User.
None: No privacy method is used.
DES: DES encryption method is used.
Enter the Privacy Password.
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User Table
Select:
User Name:
User Type:
Group Name:
Security Model:
Security Level:
Auth Mode:
Privacy Mode:
Operation:
Select the desired entry to delete the corresponding User. It is multi-optional.
Displays the name of the User.
Displays the User Type.
Displays the Group Name of the User.
Displays the Security Model of the User.
Displays the Security Level of the User.
Displays the Authentication Mode of the User.
Displays the Privacy Mode of the User.
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 Model and Security Level.
12.1.5 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.
Choose the menu
SNMP → SNMP Config → SNMP Community
to load the following page.
Figure 12-7 SNMP Community
The following entries are displayed on this screen:
Community Config
Community Name:
Access:
Enter the Community Name here.
Defines the access rights of the community.
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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.
Select the MIB View for the community to access.
MIB View:
Community Table
Select:
Community Name:
Access:
MIB View:
Operation:
Select the desired entry to delete the corresponding Community. It is multi-optional.
Displays the Community Name here.
Displays the right of the Community to access the View.
Displays the Views which the Community can access.
Click the
Edit
button to modify the MIB View and the Access right of the Community, and then click the
Modify
button to apply.
Note:
The default MIB View of SNMP Community is viewDefault.
Configuration Procedure:
If SNMPv3 is employed, please take the following steps:
Step Operation
1 Enable function globally.
2
3
4
Create SNMP View.
Create SNMP Group.
Create SNMP User.
Description
Required. On the
SNMP → SNMP Config → Global
Config
page, enable
SNMP
function globally.
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.
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.
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.
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If SNMPv1 or SNMPv2c is employed, please take the following steps:
Step Operation
1 Enable SNMP function globally.
2 Create SNMP View.
Description
Required. On the
SNMP → SNMP Config → Global
Config
page, enable
SNMP
function globally.
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.
3
Community directly.
Configure access level for the User.
Create SNMP
Group and SNMP
User.
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.
12.2 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.
On this page, you can configure the notification function of SNMP.
Choose the menu
SNMP → Notification → Notification
to load the following page.
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Figure 12-8 Notification Config
The following entries are displayed on this screen:
Create Notification
IP Address:
UDP Port:
User:
Security Model:
Security Level:
Type:
Retry:
Timeout:
Enter the IP Address of the management Host.
Enter the number of the UDP port used to send notifications.
The UDP port functions with the IP address for the notification sending. The default is 162.
Enter the User name of the management station.
Select the Security Model of the management station.
Select the Security Level for the SNMP v3 User.
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.
Select the type for the notifications.
Trap:
Indicates traps are sent.
Inform:
Indicates informs are sent. The Inform type has a higher security than the Trap type.
Specify the amount of times the switch resends an inform request. 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.
Specify the maximum time for the switch to wait for the response from the management station before resending a request.
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Notification Table
Select:
IP Address:
UDP Port:
User:
Security Model:
Security Level:
Type:
Timeout:
Retry:
Operation:
Select the desired entry to delete the corresponding management station.
Displays the IP Address of the management host.
Displays the UDP port used to send notifications.
Displays the User name of the management station.
Displays the Security Model of the management station.
Displays the Security Level for the SNMP v3 User.
Displays the type of the notifications.
Displays the maximum time for the switch to wait for the response from the management station before resending a request.
Displays the amount of times the switch resends an inform request.
Click the
Edit
button to modify the corresponding entry and click the
Modify
button to apply.
12.3 RMON
RMON (Remote Monitoring) based 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.
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 which 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.
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The
RMON
Groups can be configured on the
History Control, Event Config
and
Alarm Config
pages.
12.3.1 History Control
On this page, you can configure the History Group for RMON.
Choose the menu
SNMP → RMON → History Control
to load the following page.
Figure 12-9 History Control
The following entries are displayed on this screen:
History Control Table
Select:
Index:
Port:
Interval:
Owner:
Status:
Select the desired entry for configuration.
Displays the index number of the entry.
Specify the port from which the history samples were taken.
Specify the interval to take samplings from the port.
Enter the name of the device or user that defined the entry.
Select Enable/Disable the corresponding sampling entry.
12.3.2 Event Config
On this page, you can configure the RMON events.
Choose the menu
SNMP → RMON → Event Config
to load the following page.
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Figure 12-10 Event Config
The following entries are displayed on this screen:
Event Table
Select:
Index:
User:
Description:
Type:
Owner:
Status:
Select the desired entry for configuration.
Displays the index number of the entry.
Enter the name of the User or the community to which the event belongs.
Give a description to the event for identification.
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.
Enter the name of the device or user that defined the entry.
Select Enable/Disable the corresponding event entry.
12.3.3 Alarm Config
On this page, you can configure Statistic Group and Alarm Group for RMON.
Choose the menu
SNMP → RMON → Alarm Config
to load the following page.
183
Figure 12-11 Alarm Config
The following entries are displayed on this screen:
Alarm Table
Select:
Index:
Variable:
Port:
Sample Type:
Rising Threshold:
Rising Event:
Falling Threshold:
Falling Event:
Alarm Type:
Select the desired entry for configuration.
Displays the index number of the entry.
Select the alarm variables from the pull-down list.
Select the port on which the Alarm entry acts.
Specify the sampling method for the selected variable and comparing the value against the thresholds.
Absolute:
Compares the values directly 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.
Enter the rising counter value that triggers the Rising Threshold alarm.
Select the index of the corresponding event which will be triggered if the sampled value is larger than the Rising
Threshold.
Enter the falling counter value that triggers the Falling Threshold alarm.
Select the index of the corresponding event which will be triggered if the sampled value is lower than the Falling
Threshold.
Specify the type of the alarm.
All:
The alarm event will be triggered either the sampled value exceeds the Rising Threshold or is under the Falling
Threshold.
Rising:
When the sampled value exceeds the Rising
Threshold, an alarm event is triggered.
Falling:
When the sampled value is under the Falling
Threshold, an alarm event is triggered.
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Interval:
Owner:
Status:
Enter the alarm interval time in seconds.
Enter the name of the device or user that defined the entry.
Select Enable/Disable the corresponding alarm 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.
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Chapter 13 Cluster
With the development of network technology, the network scale is getting larger and more network devices are required, which may result in a more complicated network management system. As a large number of devices need to be assigned different network addresses and every management device needs to be respectively configured to meet the application requirements, manpower are needed.
The Cluster Management function can solve the above problem. It is mainly used to central manage the scattered devices in the network. A network administrator can manage and maintain the switches in the cluster via a management switch. The management switch is the commander of the cluster and the others are member switches.
The typical topology is as follows.
Figure 13-1 Cluster topology
Cluster Role
According to their functions and status in a cluster, switches in the cluster play different roles. You can specify the role a switch plays. There are four roles.
Commander Switch:
Indicates the device that can configure and manage all the devices in a cluster. It discovers and determins the candidate switches by collecting NDP (Neighbor Discovery
Protocol) and NTDP (Neighbor Topology Discovery Protocol).
Member Switch:
Indicates the device that is managed in a cluster.
Candidate Switch:
Indicates the device that does not belong to any cluster though it can be added to a cluster.
Individual Switch:
Indicates the device with cluster feature disabled.
The roles can be changed from one to anther following the specified rules.
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The current switch you create cluster is specified as the commander switch.
The commander switch discovers and determines candidate switches by collecting related information.
After being added to the cluster, the candidate switch becomes to be the member switch.
After being removed from the cluster, the member switch becomes to be the candidate switch.
The commander switch becomes to be the candidate switch only when the cluster is deleted.
Note:
TL-SG3210/TL-SG3216/TL-SG3424 switch cannot be configured as commander switch to manage the cluster.
Introduction to Cluster
Cluster functions to configure and manage the switches in the cluster based on three protocols,
NDP, NTDP and CMP (Cluster Management Protocol).
NDP: All switches get neighbor information by collecting NDP.
NTDP: The commander switch collects the NDP information and neighboring connection information of each device in a specific network range to determine the candidate switches in the cluster.
Cluster maintenance: The commander switch adds the candidate switch to the cluster and removes the member switch from the cluster according to the collected NTDP information.
The Cluster module, mainly used for cluster management configuration, including three submenus:
NDP
,
NTDP
and
Cluster
.
13.1 NDP
NDP (Neighbor Discovery Protocol) is used to get the information of the directly connected neighbor devices to support cluster establishing. An NDP-enabled device sends NDP packets regularly to neighbor devices as well as receives NDP packets from neighbor devices. An NDP packet carries the NDP information (including the device name, MAC address, firmware version and so on).
A switch keeps and maintains a neighbor information table, which contains the NDP information of each neighbor switch. If a switch receives the NDP information of a new neighbor, it will add the information to the neighbor information table. If the received NDP information is different from the old information, the switch will update it in the neighbor information table; if the received NDP information is the same with the old information, the switch will just update the aging time; if the switch does not receive NDP information within the aging time, the switch will remove the corresponding information from the table automatically.
The NDP function can be implemented on
Neighbor Info
,
NDP Summary
and
NDP Config
pages.
13.1.1 Neighbor Info
On this page you can view the NDP neighbor information of the switch.
Choose the menu
Cluster → NDP → Neighbor Info
to load the following page.
187
Figure 13-2 Neighbor Information
The following entries are displayed on this screen:
Neighbor
Search Option:
Select the information the desired entry should contain and then click the
Search
button to display the desired entry in the following
Neighbor Information table.
Neighbor Info
Native Port:
Remote Port:
Device Name:
Device MAC:
Firmware Version:
Aging Time:
Displays the port number of the switch.
Displays the port number of the neighbor switch which is connected to the corresponding port.
Displays the name of the neighbor switch.
Displays MAC address of the neighbor switch.
Displays the firmware version of the neighbor switch.
Displays the period for the switch s to keep the NDP packets from the neighbor switch.
13.1.2 NDP Summary
On this page you can view the NDP configuration of the switch.
Choose the menu
Cluster → NDP → NDP Summary
to load the following page.
188
Figure 13-3 NDP Summary
The following entries are displayed on this screen:
Global Config
NDP:
Aging Time:
Displays the global NDP status (enabled or disabled) for the switch.
Displays the period for the neighbor switch to keep the NDP packets from this switch.
Displays the interval to send NDP packets.
Hello Time:
Port Status
Port:
NDP:
Send NDP Packets:
Receive NDP Packets:
Error NDP Packets:
Neighbors:
Displays the port number of the switch.
Displays the NDP status (enabled or disabled) for the current port.
Displays the count of currently sent NDP packets.
Displays the count of currently received NDP packets.
Displays the count of currently received error NDP packets.
Displays the count of the connected neighbors.
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Detail
：
Click the
Detail
button to view the complete information collected for the port.
13.1.3 NDP Config
On this page you can configure the NDP function for the switch.
Choose the menu
Cluster → NDP → NDP Config
to load the following page.
Figure 13-4 NDP Config
The following entries are displayed on this screen:
Global Config
NDP:
Aging Time:
Select Enable/Disable NDP function globally.
Enter the period for the neighbor switch to keep the NDP packets from this switch.
Enter the interval to send NDP packets.
Hello Time:
Port Config
Select:
Port:
NDP:
Enable:
Select the desired port to configure its NDP status.
Displays the port number of the switch.
Displays NDP status of the current port.
Click the
Enable
button to enable NDP for the port you select.
Disable:
Click the
Disable
button to disable NDP for the port you select.
Note:
1. NDP function is effective only when NDP function is enabled globally and for the port.
190
2. The aging time should be set over the hello time value, otherwise this setting will be invalid and will not take effect.
13.2 NTDP
NTDP (Neighbor Topology Discovery Protocol
） is used for the commander switch to collect NDP information. NTDP transmits and forwards NTDP topology collection request based on NDP neighbor information table, and collects the NDP information and neighboring connection information of each device in a specific network range. The commander switch can collects the specified topology in the network regularly and you can also enable topology collection manually on the commander switch.
After the commander switch sends out NTDP request packets, lots of switches receive the request packets and send out response packets at the same time, which may result in network congestion and the commander switch overload. To avoid the above problem, two time parameters are designed to control the spread speed of NTDP request packets.
NTDP hop delay: Indicates the time between the switch receiving NTDP request packets and the switch forwarding NTDP request packets for the first time.
NTDP port delay: Indicates the time between the port forwarding NTDP request packets and its adjacent port forwarding NTDP request packets over.
The NTDP function can be implemented on
Device Table
,
NTDP Summary
and
NTDP Config
pages.
13.2.1 Device Table
On this page you can view the information of the devices collected by NTDP. Meanwhile, no matter whether a cluster is established, on this page you can manually collect NTDP information at any time to manage and control devices.
Choose the menu
Cluster → NTDP → Device Table
to load the following page.
Figure 13-5 Device Table
The following entries are displayed on this screen:
Device Table
Device Type:
Device MAC:
Cluster Name:
Displays the device description collected through NTDP.
Displays the MAC address of this device.
Displays the cluster name of this device.
191
Role:
Hops:
Neighbor Info:
Collect Topology:
Displays the role this device plays in the cluster.
Commander: Indicates the device that can configure and manage all the devices in a cluster.
Member: Indicates the device that is managed in a cluster.
Candidate: Indicates the device that does not belong to any cluster though it can be added to a cluster.
Individual: Indicates the device with cluster feature disabled.
Displays the hop count from this device to the switch.
Click the
Detail
button to view the complete information of this device and its neighbors.
Click the
Collect Topology
button to collect NTDP information of the switch so as to collect the latest network topology.
Click the
Detail
button to view the complete information of this device and its neighbors.
Figure 13-6 Information of the Current Device
13.2.2 NTDP Summary
On this page you can view the NTDP configuration.
Choose the menu
Cluster → NTDP → NTDP Summary
to load the following page.
192
Figure 13-7 NTDP Summary
The following entries are displayed on this screen:
Global Config
NTDP:
NTDP Interval Time:
NTDP Hops:
NTDP Hop Delay:
NTDP Port Delay:
Displays the NTDP status (enabled or disabled) of the switch globally.
Displays the interval to collect topology information.
Displays the hop count the switch topology collects.
Displays the time between the switch receiving NTDP request packets and the switch forwarding NTDP request packets for the first time.
Displays the time between the port forwarding NTDP request packets and its adjacent port forwarding NTDP request packets over.
Port Status
Port:
NTDP:
Displays the port number of the switch.
Displays NTDP status (enabled or disabled) of the current port.
13.2.3 NTDP Config
On this page you can configure NTDP globally.
Choose the menu
Cluster → NTDP → NTDP Config
to load the following page.
193
Figure 13-8 NTDP Config
The following entries are displayed on this screen:
Global Config
NTDP:
NTDP Interval Time:
NTDP Hops:
NTDP Hop Delay:
NTDP Port Delay:
Select Enable/Disable NTDP for the switch globally.
Enter the interval to collect topology information. The default is 1 minute.
Enter the hop count the switch topology collects. The default is 3 hops.
Enter the time between the switch receiving NTDP request packets and the switch forwarding NTDP request packets for the first time. The default is 200 milliseconds.
Enter the time between the port forwarding NTDP request packets and its adjacent port forwarding NTDP request packets over. The default is 20 milliseconds.
Port Config
Select:
Port:
NTDP:
Select the desired port for NTDP status configuration.
Displays the port number of the switch.
Displays NTDP status (enabled or disabled) of the current port.
194
Enable:
Disable:
Click the
Enable
button to enable NTDP feature for the port you select.
Click the
Disable
button to disable NTDP feature for the port you select.
Note:
NTDP function is effective only when NTDP function is enabled globally and for the port.
13.3 Cluster
A commander switch can recognize and add the candidate switch to a cluster automatically based on NDP and NTDP. You can manually add the candidate switch to a cluster. If the candidate switch is successfully added to the cluster, it will get a private IP address assigned by the commander switch. You can manage and configure the member switch via the commander switch.
The Cluster function can be implemented on
Cluster Summary
and
Cluster Config
pages.
13.3.1 Cluster Summary
On this page you can view the status of the current cluster.
Choose the menu
Cluster → Cluster → Cluster Summary
to load the following page.
For a candidate switch, the following page is displayed:
Figure 13-9 Cluster Summary for Candidate Switch
The following entries are displayed on this screen:
Global
Cluster:
Cluster Role:
Displays the cluster status (enabled or disabled) of the switch.
Displays the role the switch plays in the cluster.
For a member switch, the following page is displayed:
195
Figure 13-10 Cluster Summary for Member Switch
The following entries are displayed on this screen:
Global Config
Cluster:
Cluster Role:
Cluster Name:
Commander MAC:
Displays the cluster status (enabled or disabled) of the switch.
Displays the role the switch plays in the cluster.
Displays the name of the current cluster the switch belongs to.
Displays the MAC address of the commander switch.
For an individual switch, the following page is displayed:
Figure 13-11 Cluster Summary for Individual Switch
The following entries are displayed on this screen:
Global Config
Cluster:
Cluster Role:
Displays the cluster status (enabled or disabled) of the switch.
Displays the role the switch plays in the cluster.
13.3.2 Cluster Config
On this page you can configure the status of the cluster the switch belongs to.
Choose the menu
Cluster → Cluster → Cluster Config
to load the following page.
For a candidate switch, the following page is displayed.
196
Figure 13-12 Cluster Configuration for Candidate Switch
The following entries are displayed on this screen:
Current Role
Role:
Displays the role the current switch plays in the cluster.
Role Change
Individual:
Select this option to change the role of the switch to be individual switch.
For a member switch, the following page is displayed.
Figure 13-13 Cluster Configuration for Member Switch
The following entries are displayed on this screen:
Current Role
Role:
Displays the role the current switch plays in the cluster.
Role Change
Individual:
Select this option to change the role of the switch to be individual switch.
For an individual switch, the following page is displayed.
197
Figure 13-14 Cluster Configuration for Individual Switch
The following entries are displayed on this screen:
Current Role
Role:
Displays the role the current switch plays in the cluster.
Role Change
Candidate:
Select this option to change the role of the switch to be candidate switch.
13.4 Application Example for Cluster Function
Network Requirements
Three switches form cluster, one commander switch (Here take TP-LINK TL-SL5428E as an example) and two member switches (Here take TP-LINK TL-SG3216 as an example). The administrator manages all the switches in the cluster via the commander switch.
Port 1 of the commander switch is connecting to the external network, port 2 is connecting to member switch 1 and port 3 is connecting to member switch 2.
IP pool: 175.128.0.1, Mask: 255.255.255.0.
Network Diagram
Figure 13-15 Network diagram
198
Configuration Procedure
Configure the member switch
Step Operation
1
2
Enable NDP function on the switch and for port 1
Description
On
Cluster → NDP → NDP Config
page, enable NDP function.
Enable NTDP function on the switch and for port 1
On
Cluster → NTDP → NTDP Config
page, enable
NTDP function.
Configure the commander switch
Step Operation
1
2
3
4
Enable NDP function on the switch and for port 1, port 2 and port 3
Description
On
Cluster → NDP → NDP Config
page, enable NDP function.
Enable NTDP function on the switch and for port 1, port 2 and port 3
On
Cluster → NTDP → NTDP Config
page, enable
NTDP function.
Create a cluster and configure the related parameters
On
Cluster → Cluster → Cluster Config
page, configure the role as Commander and enter the related information.
IP pool: 175.128.0.1
Mask: 255.255.255.0
Configure the member switch On
Cluster → Cluster → Member Config
page, select the member switch and click the
Manage
button to log on to its Web management page.
Or On
Cluster → Cluster → Cluster Topology
page, double-click the switch icon to view its detailed information; click the switch icon and click the
Manage
button to log on to the Web management page.
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Chapter 14 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
）
Cable Test: Test the connection status of the cable to locate and diagnose the trouble spot of the network.
（ 4 ） Loopback: Test whether the ports of the switch and its peer device are available.
（ 5 ） Network Diagnostics: Test whether the destination device is reachable and detect the route hops from the switch to the destination device.
14.1 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.
14.1.1 CPU Monitor
Choose the menu
Maintenance → System Monitor → CPU Monitor
to load the following page.
200
Figure 14-1 CPU Monitor
Click the
Monitor
button to enable the switch to monitor and display its CPU utilization rate every four seconds.
14.1.2 Memory Monitor
Choose the menu
Maintenance → System Monitor → Memory Monitor
to load the following page.
201
Figure 14-2 Memory Monitor
Click the
Monitor
button to enable the switch to monitor and display its Memory utilization rate every four seconds.
14.2 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
Table 14-1 Log Level
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The
Log
function is implemented on the
Log Table
,
Local Log
,
Remote Log
and
Backup Log
pages.
14.2.1 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.
Figure 14-3 Log Table
The following entries are displayed on this screen:
Log Info
Index:
Time:
Module:
Severity:
Content:
Displays the index of the log information.
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.
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.
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.
Displays the content of the log information.
Note:
1. The logs are classified into eight levels based on severity. The higher the information severity is, the lower the corresponding level is.
2. This page displays logs in the log buffer, and at most 512 logs are displayed.
203
14.2.2 Local Log
Local Log is the log information saved in switch. By default, all system logs are saved in log buffer and the logs with severities from level_0 to level_2 are saved in log file meanwhile. On this page, you can set the output channel for logs.
Choose the menu
Maintenance → Log → Local Log
to load the following page.
Figure 14-4 Local Log
The following entries are displayed on this screen:
Local Log Config
Select:
Log Buffer:
Log File:
Severity:
Status:
Select the desired entry to configure the corresponding local log.
Indicates the RAM for saving system log. The inforamtion in the log buffer is displayed on the Log Table page. It will be lost when the switch is restarted.
Indicates the flash sector for saving system log. The inforamtion in the log file will not be lost after the switch is restarted and can be exported on the Backup Log page.
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.
Enable/Disable the channel.
14.2.3 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.
204
Figure 14-5 Log Host
The following entries are displayed on this screen:
Log Host
Index:
Host IP:
UDP Port:
Severity:
Status:
Displays the index of the log host. The switch supports 4 log hosts.
Configure the IP for the log host.
Displays the UDP port used for receiving/sending log information. Here we use the standard port 514.
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.
Enable/Disable the log host.
Note:
The Log Server software is not provided. If necessary, please download it on the Internet.
14.2.4 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.
Figure 14-6 Backup Log
205
The following entry is displayed on this screen:
Backup Log
Backup Log:
Click the
Backup Log
button to save the log as a file to your computer.
Note:
It will take a few minutes to backup the log file. Please wait without any operation.
14.3 Device Diagnostics
This switch provides Cable Test and Loopback functions for device diagnostics.
14.3.1 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 Diagnostics → Cable Test
to load the following page.
Figure 14-7 Cable Test
The following entries are displayed on this screen:
Cable Test
Port:
Pair:
Status:
Length:
Error:
Select the port for cable testing.
Displays the Pair number.
Displays the connection status of the cable connected to the port. The test results of the cable include normal, close, open, short, impedance or unknown.
If the connection status is normal, here displays the length range of the cable.
If the connection status is close, open or impedance, here displays the error length of the cable.
206
Note:
1. The Length displayed here is the length of pair cable not that of the physical cable.
2. The test result is just for your reference.
14.3.2 Loopback
Loopback test function, looping the sender and the receiver of the signal, is used to test whether the port of the switch is available as well as to check and analyze the physical connection status of the port to help you locate and solve network malfunctions.
Choose the menu
Maintenance → Device Diagnostics → Loopback
to load the following page.
Figure 14-8 Loopback
The following entries are displayed on this screen:
Loopback Type
Internal:
External:
Select Internal to test whether the port is available.
Select External to test whether the device connected to the port of the switch is available
Loopback Port
Loopback Port:
Test:
Select the desired port for loopback test.
Click the
Test
button to start the loopback test for the port.
14.4 Network Diagnostics
This switch provides Ping test and Tracert test functions for network diagnostics.
14.4.1 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.
207
Choose the menu
Maintenance → Network Diagnostics → Ping
to load the following page.
Figure 14-9 Ping
The following entries are displayed on this screen:
Ping Config
Destination IP:
Ping Times:
Data Size:
Interval:
Enter the IP address of the destination node for Ping test.
Enter the amount of times to send test data during Ping testing. The default value is recommended.
Enter the size of the sending data during Ping testing. The default value is recommended.
Specify the interval to send ICMP request packets. The default value is recommended.
14.4.2 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.
Choose the menu
Maintenance → Network Diagnostics → Tracert
to load the following page.
208
Figure 14-10 Tracert
The following entries are displayed on this screen:
Tracert Config
Destination IP:
Max Hop:
Enter the IP address of the destination device.
Specify the maximum number of the route hops the test data can pass through.
209
Appendix A: Specifications
Standards
Transmission Rate
Transmission Medium
LED
IEEE802.3 10Base-T Ethernet
IEEE802.3u 100Base-TX/100Base-FX Fast Ethernet
IEEE802.3ab 1000Base-T Gigabit Ethernet
IEEE802.3z 1000Base-X Gigabit Ethernet
IEEE802.3x Flow Control
IEEE802.1p QoS
IEEE802.1q VLAN
IEEE802.1X Port-based Access Authentication
Ethernet: 10Mbps HD
，
20Mbps FD
Fast Ethernet: 100Mbps HD
，
200Mbps FD
Gigabit Ethernet: 2000Mbps FD
10Base-T: UTP/STP of Cat. 3 or above
100Base-TX: UTP/STP of Cat. 5 or above
100Base-FX: MMF or SMF SFP Module (Optional)
1000Base-T: 4-pair UTP ( ≤ 100m) of Cat. 5, Cat. 5e, Cat.6
or above
1000Base-X: MMF or SMF SFP Module (Optional)
Power, System,1000Mbps, Link/Act
Transmission Method
Store and Forward
Packets Forwarding Rate
10BASE-T
：
14881pps/port
100BASE-TX
：
148810pps/port
1000Base-T
：
1488095pps/port
Operating
Environment
Operating Temperature: 0 ~ 40
℃
Storage Temperature: -40 ~ 70
℃
Operating Humidity: 10% ~ 90% RH Non-condensing
Storage Humidity: 5% ~ 90% RH Non-condensing
210
Appendix B: Configuring the PCs
In this section, we’ll introduce how to install and configure the TCP/IP correctly in Windows 2000.
First make sure your Ethernet Adapter is working, refer to the adapter’s manual if necessary.
1) On the Windows taskbar, click the
Start
button, and then click
Control Panel
. the icon, and then click on the
Network
Connections
tab in the appearing window.
3) Right click the icon that showed below, select Properties on the prompt page.
Figure B-1
4) In the prompt page that showed below, double click on the
Internet Protocol (TCP/IP)
.
Figure B-2
211
following window will display and the
IP Address
tab is open on this window by default.
Figure B-3
6) Select . And the following items will be available. If the switch's
IP address is 192.168.0.1, specify IP address as 192.168.0.x (x is from 2 to 254), and the
Subnet mask
as 255.255.255.0.
Now:
Click
OK
to save your settings.
212
Appendix C: Load Software Using FTP
If there is something wrong with the firmware of the switch and the switch cannot be launched, you can load firmware to the switch via FTP function. FTP (File Transfer Protocol), a protocol in the application layer, is mainly used to transfer files between the remote server and the local PCs. It is a common protocol used in the IP network for files transfer.
1. Hardware Installation
Figure C-1
1
）
Connect FTP server to port 1 of the switch.
2
）
Connect the Console port of the PC to the switch.
3
）
Save the firmware of the switch in the shared file of FTP server. Please write down the user name, password and the firmware name.
2. Configure the Hyper Terminal
After the hardware installation, please take the following steps to configure the hyper terminal of the management PC to manage the switch.
1
）
Select
Start
→
All Programs
→
Accessories
→
Communications
→
Hyper Terminal
to open hyper terminal.
213
Figure C-2 Open Hyper Terminal
2
）
The Connection Description Window will prompt shown as Figure C-3. Enter a name into the Name field and click
OK
.
Figure C-3 Connection Description
3
）
Select the port to connect in the following figure and then click
OK
.
214
Figure C-4 Select the port to connect
4
）
Configure the port selected in the step above shown as the following figure. Configure
Bits per second
as 38400,
Data bits
as 8,
Parity
as None,
Stop bits
as 1,
Flow control
as None, and then click
OK
.
Figure C-5 Port Settings
3. Download Firmware via bootUtil menu
To download firmware to the switch via FTP function, you need to enter into the bootUtil menu of the switch and take the following steps.
1 ） Connect the console port of the PC to the console port of the switch and open hyper terminal. Connect FTP server to port 1 of the switch.
2 ） Power off and restart the switch. When you are prompted that “Press CTRL-B to enter the bootUtil” in the hyper terminal, please press CTRL-B key to enter into bootUtil menu shown as the figure below.
215
Figure C-6 bootUtil Menu
As the prompt is displayed for a short time, you are suggested not to release the CTRL-B key until you enter into bootUtil menu after powering on the switch.
3
）
After entering into bootUtil menu, please firstly configure the IP parameters of the switch.
The format is:
ifconfig ip
xxx.xxx.xxx.xxx
mask
255.255.255.0
gateway
xxx.xxx.xxx.xxx.
For example: Configure the IP address as 192.168.0.22, mask as 255.255.255.0 and gateway as192.168.0.1. The detailed command is shown as the figure below. Enter the command and press
Enter
.
[TL-SG3216] :
ifconfig ip
192.168.0.22
mask 255.255.255.0 gateway
192.168.0.1
4
）
Configure the parameters of the FTP server which keeps the upgrade firmware. Later you can download the firmware to the switch from the FTP server. The format of the command is:
ftp host
xxx.xxx.xxx.xxx
user
xxxxx
pwd
xxxxx
file
xxxxxx.bin.
Here take the following parameters of the FTP server as an example. IP address is
192.168.0.146; the user name and password for login to the FTP server are both 123; the name of the upgrade firmware is tl_sg3216_up.bin. The detailed command is shown as the following figure. Enter the command and press
Enter
.
[TL-SG3216] :
ftp host
192.168.0
.146 user 123 pwd 123 file tl_sg3216_up.bin
5 ） Enter the upgrade command and press
Enter
to upgrade the firmware. After a while, the prompt “You can only use the port 1 to upgrade” will display in the hyper terminal shown as the following figure.
[TL-SG3216] :
upgrade
You can only use the port 1 to upgrade.
6
）
When the prompt “Are you sure to upgrade the firmware[Y/N]:” displays, please enter
Y
to start upgrade or enter
N
to quit upgrade shown as the following figure. The # icon indicates it is upgrading. After upgrading, the [TL-SG3216] command will display.
Are you sure to upgrade the firmware[Y/N] :
y
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
# # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
[TL-SG3216] :
7
）
Please enter start command to start the switch shown as the following figure. Enter the user name and password (the default user name and password are both admin) to login to the CLI command window and you can manage the switch via CLI command.
216
[TL-SG3216] :
start
Start . . . . . . . . . .
* * * * * * * * * * * * * * * * * * * * * *
User Access Login
* * * * * * * * * * * * * * * * * * * * * *
User :
217
Appendix D: 802.1X Client Software
In 802.1X mechanism, the supplicant Client should be equipped with the corresponding client software complied with 802.1X protocol standard for 802.1X authentication. When the switch
TL-SG3216 works as the authenticator system, please take the following instructions to install the
TpSupplicant provided on the attached CD for the supplicant Client.
1) Insert the provided CD into your CD-ROM drive. Open the file folder and double click the icon continue.
to load the following figure. Choose the proper language and click
Next
to
Figure D-1 Choose Setup Language
2) Please wait for the InstallShield Wizard preparing the setup shown as the following screen.
Figure D-2 Preparing Setup
3) Then the following screen will appear. Click
Next
to continue. If you want to stop the installation, click
Cancel
.
218
Figure D-3 Welcome to the InstallShield Wizard
4) To continue, choose the destination location for the installation files and click
Next
on the following screen.
Figure D-4 Choose Destination Location
By default, the installation files are saved on the Program Files folder of system disk. Click the
Change
button to modify the destination location proper to your need.
5) Till now, The Wizard is ready to begin the installation. Click
Install
to start the installation on the following screen.
219
Figure D-5 Install the Program
6) The InstallShield Wizard is installing TpSupplicant shown as the following screen. Please wait.
Figure D-6 Setup Status
7) On the following screen, click
Finish
to complete the installation.
220
Figure D-7 InstallShield Wizard Complete
Note:
Please pay attention to the tips on the above screen. If you have not installed WinPcap 4.0.2 or the higher version on your computer, the 802.1X Client Software TpSupplicant can not work. It’s recommended to go to http://www.winpcap.org to download the latest version of WinPcap for installation.
If you want to remove the TpSupplicant, please take the following steps:
1) On the Windows taskbar, click the
Start
button, point to
All Programs
TP-LINK
TpSupplicant
, and then click
Uninstall TP-LINK 802.1X
, shown as the following figure.
Figure D-8 Uninstall TP-LINK 802.1X
221
2) Then the following screen will appear. If you want to stop the remove process, click
Cancel
.
Figure D-9 Preparing Setup
3) On the continued screen, click
Yes
to remove the application from your PC.
4) Click to complete.
Figure D-10 Uninstall the Application
3. Configuration
Figure D-11 Uninstall Complete
1) After completing installation, double click the icon to run the TP-LINK 802.1X Client
Software. The following screen will appear.
222
Figure D-12 TP-LINK 802.1X Client
Enter the
Name
and the
Password
specified in the Authentication Server. The length of
Name
and
Password
should be less than 16 characters. the button on Figure D-12 to load the following screen for configuring the connection properties.
Figure D-13 Connection Properties
Send 802.1X protocol packets by Unicast:
When this option is selected, the Client will send the
EAPOL Start packets to the switch via multicast and send the 802.1X authentication packets via unicast.
Obtain an IP address automatically:
Select this option if the Client automatically obtains the IP address from DHCP server. After passing the authentication, the Client can be assigned the IP address by DHCP server. The Client can access the network after getting the new IP address.
Auto reconnect after timeout:
Select this option to allow the Client to automatically start the connection again when it does not receive the handshake reply packets from the switch within a period.
223
3) To continue, click
Connect
button after entering the
Name
and
Password
on Figure D-12.
Then the following screen will appear to prompt that the Radius server is being searched.
Figure D-14 Authentication Dialog
4) When passing the authentication, the following screen will appear.
Figure D-15 Successfully Authenticated
5) Double click the icon on the right corner of desktop, and then the following connection status screen will pop up.
Figure D-16 Connection Status
4. FAQ:
Q1:
Why does this error dialog box pop up when starting up the TP-LINK 802.1X Client Software?
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A1:
It’s because the supported DLL file is missing. You are suggested to go to http://www.winpcap.org to download WinPcap 4.0.2 or the higher version for installation, and run the client software again.
Q2:
Is this TP-LINK 802.1X Client Software compliable with the switches of the other manufacturers?
A2:
No. This TP-LINK 802.1X Client Software is customized for TP-LINK switches.
Q3:
Is it safe to set the password being automatically saved ？
A3:
Yes. The password saved in the configuration files is encrypted.
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Appendix E: 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.
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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 is made 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.
Multicast Switching
A process whereby the switch filters incoming multicast frames for services which no attached host has registered, or forwards them to all ports contained within the designated multicast group.
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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-slave 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.
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.
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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.
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Key Features
- Layer 2 Switch
- Link aggregation
- QoS
- Security
- Manageability