TP Link Video Games TL SL2428 User Manual

TL-SL2428  
24-Port 10/100Mbps + 4-Port Gigabit  
Smart Switch  
Rev: 1.0.0  
1910010675  
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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:  
AT  
ES  
LT  
BG  
FI  
BY  
FR  
MT  
SK  
CA  
GB  
NL  
TR  
CZ  
GR  
NO  
UA  
DE  
HU  
PL  
DK  
IE  
EE  
IT  
LV  
SE  
PT  
RO  
RU  
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CONTENTS  
III  
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IV  
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V
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Package Contents  
The following items should be found in your box:  
One TL-SL2428 24-Port 10/100Mbps + 4-Port Gigabit Smart Switch  
One power cord  
Two mounting brackets and other fittings  
Installation Guide  
Resource CD for TL-SL2428 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-SL2428 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 TL-SL2428 mentioned in this Guide stands for TL-SL2428 24-Port 10/100Mbps  
+ 4-Port Gigabit Smart Switch without any explanation.  
Menu NameSubmenu NameTab page indicates the menu structure. SystemSystem  
InfoSystem 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  
Ignoring this type of note might result in a malfunction or damage to the  
device.  
Note:  
Tips:  
This format indicates important information that helps you make better use  
of your device.  
1.3 Overview of This Guide  
Chapter  
Introduction  
Chapter 1 About This Guide  
Chapter 2 Introduction  
Introduces the guide structure and conventions.  
Introduces the features, application and appearance of TL-SL2428  
switch.  
Chapter 3 Login to the Switch  
Introduces how to log on to TL-SL2428 Web management page.  
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Chapter  
Introduction  
Chapter 4 System  
This module is used to configure system properties of the switch.  
Here mainly introduces:  
System Info: Configure the description, system time, Daylight  
Saving Time and network parameters of the switch.  
User Manage: 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: Access Security is configured to control the  
users logging on to the Web management page.  
Chapter 5 Switching  
This module is used to configure basic functions of the switch. Here  
mainly introduces:  
Port: Configure the basic features for the port.  
LAG: Configure Link Aggregation Group. LAG is to combine a  
number of ports together to make a single high-bandwidth data  
path.  
Traffic Monitor: Monitor the traffic of each port  
MAC Address: Configure the address table of the switch.  
Chapter 6 VLAN  
This module is used to configure VLANs to control broadcast in  
LANs. Here mainly introduces:  
802.1Q VLAN: Configure port-based VLAN.  
Chapter 7 Spanning Tree  
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.  
Chapter 8 Multicast  
This module is used to configure multicast function of the switch.  
Here mainly introduces:  
IGMP Snooping: Configure global parameters of IGMP Snooping  
function, port properties, VLAN and multicast VLAN.  
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.  
Chapter 9 QoS  
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.  
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Chapter  
Introduction  
Chapter 10 SNMP  
This module is used to configure SNMP function to provide a  
management frame to monitor and maintain the network devices.  
Here mainly introduces:  
SNMP Config: Configure global settings of SNMP function.  
Notification: Configure notification function for the management  
station to monitor and process the events.  
RMON: Configure RMON function to monitor network more  
efficiently.  
Chapter 11 Maintenance  
This module is used to assemble the commonly used system tools  
to manage the switch. Here mainly introduces:  
System Monitor: Monitor the memory and CPU of the switch.  
Log: View configuration parameters on the switch.  
Device Diagnose:  
Cable Test: Test the connection status of the cable connected  
to the switch.  
Loopback: Test if the port of the switch and the connected  
device are available.  
Network Diagnose: Test if the destination is reachable and the  
account of router hops from the switch to the destination.  
Appendix A Specifications  
Appendix B Configure the PCs  
Appendix C Glossary  
Lists the hardware specifications of the Switch  
Introduces how to configure the PCs.  
Lists the glossary used in this manual.  
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Chapter 2 Introduction  
Thanks for choosing the TL-SL2428 24-Port 10/100Mbps + 4-Port Gigabit Smart Switch!  
2.1 Overview of the Switch  
Designed for workgroups and departments, TL-SL2428 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. QoS and IGMP snooping/filtering optimize voice and video  
application. SNMP, RMON, WEB Log-in bring abundant management policies. TL-SL2428 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  
+ 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  
+ Supports 255 active VLAN groups and 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  
+ Control the users logging on to the Web management page.  
Manageability  
+ Supports SNMP v1/v2c/v3, RMON and web access.  
+ Port Mirroring enables monitoring selected ingress/egress traffic.  
2.3 Appearance Description  
2.3.1 Front Panel  
Figure 2-1 Front Panel  
The following parts are located on the front panel of the Switch:  
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Reset: With the Switch powered on, press Reset button for five seconds to reset the software  
setting to its factory default settings.  
10/100Mbps Ports: Designed to connect to the device with a bandwidth of 10Mbps or  
100Mbps. Each has a corresponding 10/100M LED.  
10/100/1000Mbps Ports: Designed to connect to the device with a bandwidth of 10Mbps,  
100Mbps or 1000Mbps. Each has a corresponding 1000M LED.  
SFP Ports: Designed to install the SFP module. It shares LEDs with 1000Mbps ports. When a  
1000Mbps SFP module is inserted into the SFP port, On (green) LED of 1000M means a  
device is linked to the port and Flashing (green) LED of 1000M indicates data is being  
transmitted or received on the port.  
LEDs  
Name  
Status  
Indication  
On(green) The Switch is powered on.  
Power  
Flashing/Off The Switch is powered off or power supply is abnormal.  
Flashing  
On/Off  
On  
The Switch is working normally.  
System  
The Switch is powered off or the Switch is working abnormally.  
A device is linked to the corresponding port.  
Data is being transmitted or received.  
Flashing  
Green  
Yellow  
On  
10/100M  
The linked device is running at 100Mbps.  
The linked device is running at 10Mbps.  
A device is linked to the corresponding port.  
Data is being transmitted or received.  
Flashing  
Green  
Yellow  
1000M  
The linked device is running at 1000Mbps.  
The linked device is running at 10/100Mbps.  
Note:  
When using the SFP port with a 100M module or a gigabit module, you need log on to the GUI  
(Graphical User Interface) of the Switch and configure its corresponding Speed and Duplex mode  
on SwitchingPortPort 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.  
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2.3.2 Rear Panel  
The rear panel of TL-SL2428 features a power socket and a Grounding Terminal (marked with ).  
Figure 2-2 Rear Panel  
Grounding Terminal: TL-SL2428 already comes with Lightning Protection Mechanism. You  
can also ground the Switch through the PE (Protecting Earth) cable of AC cord or with Ground  
Cable. For detail information, please refer to Installation Guide.  
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 Saving  
Config. You are suggested to click Saving 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 Manage, 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 24 10/100Mbps RJ45 ports, 4  
10/100/1000Mbps RJ45 ports and 2 SFP ports of the switch. The ports labeled as 1-24 are  
10/100Mbps ports; the ports labeled as 26-28 are 10/100/1000Mbps ports; the ports labeled as  
27F and 28F are SFP ports.  
Choose the menu SystemSystem InfoSystem Summary to load the following page.  
Figure 4-1 System Summary  
Port Status  
Indicates the 100Mbps port is not connected to a device.  
Indicates the 100Mbps port is at the speed of 100Mbps.  
Indicates the 100Mbps port is at the speed of 10Mbps.  
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Indicates the 1000Mbps port is not connected to a device.  
Indicates the 1000Mbps port is at the speed of 1000Mbps.  
Indicates the 1000Mbps port is at the speed of 10Mbps or 100Mbps.  
Indicates the SFP port is not connected to a device.  
Indicates the SFP port is at the speed of 1000Mbps.  
Indicates the SFP port is 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:  
Displays the port number of the switch.  
Displays the type of the port.  
Type:  
Speed:  
Status:  
Displays the maximum transmission speed 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. Figure 4-3 displays the bandwidth utilization monitored  
every four seconds. Monitoring the bandwidth utilization on each port facilitates you to monitor the  
network traffic and analyze the network abnormities.  
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Figure 4-3 Bandwidth Utilization  
Bandwidth Utilization  
Rx:  
Select Rx to display the bandwidth utilization of receiving packets  
on this port.  
Tx:  
Select Tx to display the bandwidth utilization of sending packets  
on this port.  
4.1.2 Device Description  
On this page you can configure the description of the switch, including device name, device location  
and system contact.  
Choose the menu SystemSystem InfoDevice Description to load the following page.  
Figure 4-4 Device Description  
The following entries are displayed on this screen:  
Device Description  
Device Name:  
Enter the name of the switch.  
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Device Location:  
System Contact:  
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, or synchronize with PC’s clock as the system time.  
Choose the menu SystemSystem InfoSystem Time to load the following page.  
Figure 4-5 System Time  
The following entries are displayed on this screen:  
Time Info  
Current  
Date:  
System  
Time  
Displays the current date and time of the switch.  
Displays the current time source of the switch.  
Current  
Source:  
Time Config  
Manual:  
When this option is selected, you can set the date and time  
manually.  
Synchronize  
PC’S Clock:  
with  
When this option is selected, the administrator PC’s clock is  
utilized.  
Note:  
The system time will be restored to the default when the switch is restarted and you need  
reconfigure the system time of the switch.  
4.1.4 Daylight Saving Time  
On this page you can configure the Daylight Saving Time of the switch, including DST Status,  
Predefined Mode, Recurring Mode and Date Mode.  
Choose the menu SystemSystem InfoDaylight Saving Time to load the following page.  
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Figure 4-6 System Time  
The following entries are displayed on this screen:  
DST Status:  
Enable or Disable the DST.  
Predefined Mode:  
Select a predefined DST configuration.  
USA: First Sunday in April, 02:00 ~ Last Sunday in October,  
02:00.  
Australia: First Sunday in October, 02:00 ~ First Sunday in  
April, 03:00.  
European: Last Sunday in March, 01:00 ~ Last Sunday in  
October, 01:00.  
New Zealand: First Sunday in October, 02:00 ~ Last Sunday in  
March, 03:00.  
Recurring Mode:  
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.  
Date Mode:  
Specify the DST configuration in Date mode. This configuration is  
one-off in use.  
Offset: Specify the time adding in minutes when Daylight  
Saving Time comes  
Start/End Time: Select starting time and ending time of Daylight  
Saving Time  
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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 SystemSystem InfoSystem 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:  
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.  
Management VLAN:  
Enter the ID of management VLAN, the only VLAN through which  
you can get access to the switch. By default VLAN1 owning all the  
ports is the Management VLAN and you can access the switch via  
any port on the switch. However, if another VLAN is created and  
set to be the Management VLAN, you may have to reconnect the  
management station to a port that is a member of the  
Management VLAN.  
IP Address:  
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.  
Subnet Mask:  
Enter the subnet mask of the switch.  
Enter the default gateway of the switch.  
Default Gateway:  
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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, the switch will keep obtaining IP address from DHCP server until success.  
4. If DHCP or BOOTP option is selected, the switch will gets network parameters dynamically  
from the Internet, so IP address, subnet mask and default gateway can not be configured.  
5. By default, the default IP address is 192.168.0.1.  
4.2 User Manage  
User Manage 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 Manage 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 SystemUser ManageUser 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 SystemUser ManageUser 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:  
Create a name for users’ login.  
Select the access level to login.  
Access Level:  
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.  
User Status:  
Select Enable/Disable the user configuration.  
Type a password for users’ login.  
Retype the password.  
Password:  
Confirm 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,  
Displays the current user ID, user name, access level and user  
status.  
Access Level and  
status:  
Operation:  
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 SystemSystem ToolsConfig 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 SystemSystem ToolsConfig 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 SystemSystem ToolsFirmware 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 SystemSystem ToolsSystem 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 SystemSystem ToolsSystem 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 is configured to control the users logging on to the Web management page.  
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 Manage.  
Choose the menu SystemAccess SecurityAccess 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:  
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.  
IP Address&Mask  
MAC Address:  
Port:  
These fields can be available for configuration only when IP-based  
mode is selected. Only the users within the IP-range you set here  
are allowed for 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 are allowed for login.  
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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  
Select Enable/Disable the Number Control function.  
Number Control;  
Admin Number:  
Enter the maximum number of the users logging on to the Web  
management page as Admin.  
Guest Number:  
Enter the maximum number of the users logging on to the Web  
management page as Guest.  
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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 and Port Isolation 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 SwitchingPortPort Config to load the following page.  
Figure 5-1 Port Config  
Here you can view and configure the port parameters.  
Port Config  
Port Select:  
Click the Select button to quick-select the corresponding port  
based on the port number you entered.  
Select:  
Select the desired port for configuration. It is multi-optional.  
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Port:  
Displays the port number.  
Description:  
Status:  
Give a description to the port for identification.  
Allows you to Enable/Disable the port. When Enable is  
selected, the port can forward the packets normally.  
Speed and Duplex:  
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.  
Flow Control:  
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.  
LAG:  
Note:  
Displays the LAG number which the port belongs to.  
1.  
The switch can not be managed through the disabled port. Please enable the port which is  
used to manage the switch.  
2.  
3.  
The parameters of the port members in a LAG should be set as the same.  
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.  
5.1.2 Port Mirror  
Port Mirror, a 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 SwitchingPortPort Mirror to load the following page.  
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Figure 5-2 Mirroring Port  
The following entries are displayed on this screen.  
Mirror Group List  
Group:  
Displays the mirror group number.  
Mirroring:  
Mode:  
Displays the mirroring port number.  
Displays the mirror mode, the value will be "Ingress" or "Egress",  
Displays the mirrored ports.  
Mirrored Port:  
Operation:  
Click Edit to configure the mirror group.  
Click Edit to display the following figure.  
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Figure 5-3 Mirroring Port  
The following entries are displayed on this screen.  
Mirror Group  
Number:  
Select the mirror group number you want to configure.  
Select the mirroring port number.  
Mirroring Port  
Mirroring Port:  
Mirrored Port  
Port Select:  
Click the Select button to quick-select the corresponding port based  
on the port number you entered.  
Select:  
Port:  
Select the desired port as a mirrored port. It is multi-optional.  
Displays the port number.  
Ingress:  
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.  
Egress:  
Select Enable/Disable the Egress feature. When the Egress is  
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enabled, the outgoing packets sent by the mirrored port will be  
copied to the mirroring port.  
LAG:  
Note:  
Displays the LAG number which the port belongs to. The LAG  
member can not be selected as the mirrored port or mirroring port.  
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 SwitchingPortPort Security to load the following page.  
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Figure 5-4 Port Security  
The following entries are displayed on this screen:  
Port Security  
Select:  
Select the desired port for Port Security configuration. It is  
multi-optional.  
Port:  
Displays the port number.  
Max Learned MAC:  
Specify the maximum number of MAC addresses that can be  
learned on the port.  
Learned Num:  
Learn Mode:  
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.  
Status:  
Select Enable/Disable the Port Security feature for the port.  
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Note:  
The Port Security function is disabled for the LAG port member. Only the port is removed from the  
LAG, will the Port Security function be available for the port.  
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 “SwitchingPortPort Isolation” to load the following page.  
Figure 5-5 Port Isolation Config  
The following entries are displayed on this screen:  
Port Isolation Config  
Port:  
Select the port number to set its forwardlist.  
Select the port that to be forwarded to.  
Forward Portlist:  
Port Isolation List  
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Port:  
Display the port number.  
Display the forwardlist.  
Forward Portlist:  
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, VLAN, port attributes, MAC Address Learning mode  
and other associated settings. The further explains are following:  
If the ports, which are enabled for the STP, QoS, Port Isolation 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,  
and Static MAC Address Binding, can not be added to the LAG.  
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.  
The LAG function is implemented on the LAG Table and Static LAG 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 SwitchingLAGLAG Table to load the following page.  
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Figure 5-6 LAG Table  
The following entries are displayed on this screen:  
Global Config  
Hash Algorithm:  
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:  
Select the desired LAG. It is multi-optional.  
Displays the LAG number here.  
Group Number:  
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.  
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Figure 5-7 Detail Information  
5.2.2 Static LAG  
On this page, you can manually configure the LAG.  
Choose the menu SwitchingLAGStatic LAG to load the following page.  
Figure 5-8 Static LAG  
The following entries are displayed on this screen:  
LAG Config  
Group Number:  
Description:  
Select a Group Number for the LAG.  
Displays the description of LAG.  
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Member Port  
Member Port:  
Select the port as the LAG member. Clearing all the ports of  
the LAG will delete this LAG.  
Tips:  
The LAG can be deleted by clearing its all member ports.  
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 SwitchingTraffic MonitorTraffic Summary to load the following page.  
Figure 5-9 Traffic Summary  
The following entries are displayed on this screen:  
Auto Refresh  
Auto Refresh:  
Allows you to Enable/Disable refreshing the Traffic Summary  
automatically.  
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Refresh Rate:  
Traffic Summary  
Port Select:  
Enter a value in seconds to specify the refresh interval.  
Click the Select button to quick-select the corresponding port based  
on the port number you entered.  
Port:  
Displays the port number.  
Packets Rx:  
Displays the number of packets received on the port. The error  
packets are not counted in.  
Packets Tx:  
Octets Rx:  
Displays the number of packets transmitted on the port.  
Displays the number of octets received on the port. The error octets  
are counted in.  
Octets Tx:  
Statistics:  
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 SwitchingTraffic MonitorTraffic Statistics to load the following page.  
Figure 5-10 Traffic Statistics  
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The following entries are displayed on this screen:  
Auto Refresh  
Auto Refresh:  
Allows you to Enable/Disable refreshing the Traffic Summary  
automatically.  
Refresh Rate:  
Statistics  
Port:  
Enter a value in seconds to specify the refresh interval.  
Enter a port number and click the Select button to view the traffic  
statistics of the corresponding port.  
Received:  
Sent:  
Displays the details of the packets received on the port.  
Displays the details of the packets transmitted on the port.  
Broadcast:  
Displays the number of good broadcast packets received or  
transmitted on the port. The error frames are not counted in.  
Multicast:  
Displays the number of good multicast packets received or  
transmitted on the port. The error frames are not counted in.  
Unicast:  
Displays the number of good unicast packets received or  
transmitted on the port. The error frames are not counted in.  
Alignment Errors:  
Displays the number of the received packets that have a bad  
Frame Check Sequence (FCS) with a non-integral octet  
(Alignment Error). The length of the packet is between 64 bytes  
and 1518 bytes.  
UndersizePkts:  
Displays the number of the received packets (excluding error  
packets) that are less than 64 bytes long.  
Pkts64Octets:  
Displays the number of the received packets (including error  
packets) that are 64 bytes long.  
Pkts65to127Octets:  
Pkts128to255Octets:  
Pkts256to511Octets:  
Pkts512to1023Octets:  
PktsOver1023Octets:  
Collisions:  
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 more than 1023 bytes long.  
Displays the number of collisions experienced by a port during  
packet transmissions.  
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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 facilitate the  
switch to reduce broadcast packets and enhance the efficiency of packets forwarding remarkably.  
The address filtering feature allows the switch to filter the undesired packets and forbid its  
forwarding so as to improve the network security.  
The types and the features of the MAC Address Table are listed as the following:  
Type  
Configuration Aging out Being kept after Relationship between the  
Way  
reboot  
bound MAC address and  
the port  
(if the configuration  
is saved)  
Static  
Address  
Table  
Manually  
configuring  
No  
Yes  
No  
Yes  
The bound MAC address can  
not be learned by the other  
ports in the same VLAN.  
Dynamic  
Address  
Table  
Automatically  
learning  
No  
The bound MAC address can  
be learned by the other ports  
in the same VLAN.  
Filtering  
Address  
Table  
Manually  
configuring  
Yes  
-
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 SwitchingMAC AddressAddress Table to load the following page.  
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Figure 5-11 Address Table  
The following entries are displayed on this screen:  
Search Option  
MAC Address:  
VLAN ID:  
Port:  
Enter the MAC address of your desired entry.  
Enter the VLAN ID of your desired entry.  
Select the corresponding port number of your desired entry.  
Select the type of your desired entry.  
Type:  
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:  
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.  
Port:  
Type:  
Aging Status:  
Displays the Aging status of the MAC address.  
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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 SwitchingMAC AddressStatic Address to load the following page.  
Figure 5-12 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:  
Select the entry to delete or modify the corresponding port number. It  
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is multi-optional.  
MAC Address:  
VLAN ID:  
Port:  
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.  
Type:  
Displays the Type of the MAC address.  
Aging Status:  
Displays the Aging Status of the MAC address.  
Note:  
1. If the corresponding port number of the MAC address is not correct, or the connected port (or  
the device) has been changed, the switch 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.  
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 aging out the MAC address.  
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 SwitchingMAC AddressDynamic Address to load the following page.  
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Figure 5-13 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.  
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.  
MAC Address:  
VLAN ID:  
Port:  
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.  
Type:  
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Aging Status:  
Bind:  
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 SwitchingMAC AddressFiltering Address to load the following page.  
Figure 5-14 Filtering Address  
The following entries are displayed on this screen:  
Create Filtering Address  
MAC Address:  
VLAN ID:  
Enter the MAC Address to be filtered.  
Enter the corresponding VLAN ID of the MAC address.  
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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:  
Select the entry to delete the corresponding filtering address. It is  
multi-optional.  
MAC Address:  
VLAN ID:  
Port:  
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.  
Type:  
Aging Status:  
Note:  
The MAC address in the Filtering Address Table can not be added to the Static Address Table or  
bound to a port dynamically.  
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Chapter 6 VLAN  
The traditional Ethernet is a data network communication technology basing on CSMA/CD (Carrier  
Sense Multiple Access/Collision Detect) via shared communication medium. Through the  
traditional Ethernet, the overfull hosts in LAN will result in serious collision, flooding broadcasts,  
poor performance or even breakdown of the Internet. Though connecting the LANs through  
switches can avoid the serious collision, the flooding broadcasts can not 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 and  
etc. The following figure illustrates a VLAN implementation.  
Figure 6-1 VLAN implementation  
Compared with the traditional Ethernet, VLAN enjoys the following advantages.  
1Broadcasts are confined to VLANs. This decreases bandwidth utilization and improves  
network performance.  
2Network 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.  
3Network 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  
segment. This switch supports 802.1Q VLAN to classify VLANs. VLAN tags in the packets are  
necessary for the switch to identify packets of different VLANs. The switch can analyze the  
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received untagged packets on the port and match the packets with the 802.1Q VLAN. 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  
1TPID: TPID is a 16-bit field, indicating that this data frame is VLAN-tagged. By default, it is  
0x8100.  
2Priority: Priority is a 3-bit field, referring to 802.1p priority. Refer to section “QoS & QoS  
profile” for details.  
3CFI: 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.  
4VLAN ID: VLAN ID is a 12-bit field, indicating the ID of the VLAN to which this packet  
belongs. It is in the range of 0 to 4,095. Generally, 0 and 4,095 is not used, so the field is in  
the range of 1 to 4,094.  
VLAN ID identifies the VLAN to which a packet belongs. When the switch receives an  
un-VLAN-tagged packet, it will encapsulate a VLAN tag with the default VLAN ID of the inbound  
port for the packet, and the packet will be assigned to the default VLAN of the inbound port for  
transmission.  
In this User Guide, the tagged packet refers to the packet with VLAN tag whereas the untagged  
packet refers to the packet without VLAN tag, and the priority-tagged packet refers to the packet  
with VLAN tag whose VLAN ID is 0.  
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:  
1ACCESS: 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.  
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2TRUNK: The TRUNK port can be added in multiple VLANs, and the egress rule of the port  
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.  
3GENERAL: 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 un-VLAN-tagged  
packet, it will add a VLAN tag to the packet according to the PVID of its received port and forward  
the packets.  
When creating VLANs, the PVID of each port, indicating the default VLAN to which the port  
belongs, is an important parameter with the following two purposes:  
1When the switch receives an un-VLAN-tagged packet, it will add a VLAN tag to the packet  
according to the PVID of its received port  
2PVID 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  
Forwarding Packets  
Untagged Packets  
Tagged Packets  
If the VID of packet is  
the same as the PVID  
of the port, the packet  
will be received.  
The  
packet  
will  
be  
Access  
Trunk  
forwarded after removing its  
VLAN tag.  
If the VID of packet is  
not the same as the  
PVID of the port, the  
packet will be dropped.  
When  
packets  
untagged  
are  
received, the port  
will add the default  
VLAN tag, i.e. the  
PVID of the ingress  
port, to the packets.  
The  
packet  
will  
be  
forwarded with its current  
VLAN tag.  
If the VID of packet is  
allowed by the port, the  
packet will be received.  
If the egress rule of port is  
TAG, the packet will be  
forwarded with its current  
VLAN tag.  
If the VID of packet is  
forbidden by the port,  
the packet will be  
dropped.  
General  
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  
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IEEE 802.1Q VLAN function is implemented on the VLAN Config and Port Config pages.  
6.1.1 VLAN Config  
On this page, you can view the current created 802.1Q VLAN.  
Choose the menu VLAN802.1Q VLANVLAN 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. The Web Management Page of switch can only be accessed through the ports in VLAN1.  
VLAN1 can not be modified or deleted.  
The following entries are displayed on this screen:  
VLAN Table  
Click the Select button to quick-select the corresponding entry  
VLAN ID Select:  
based on the VLAN ID number you entered.  
Select the desired entry to delete the corresponding VLAN. It is  
multi-optional.  
Select:  
Displays the ID number of VLAN.  
VLAN ID:  
Displays the user-defined description of VLAN.  
Displays the port members in the VLAN.  
Description:  
Members:  
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.  
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Figure 6-4 Create or Modify 802.1Q VLAN  
The following entries are displayed on this screen:  
VLAN Config  
VLAN ID:  
Enter the ID number of VLAN.  
Description:  
Give a description to the VLAN for identification.  
VLAN Members  
Port Select:  
Click the Select button to quick-select the corresponding entry  
based on the port number you entered.  
Select:  
Select the desired port to be a member of VLAN or leave it blank.  
It's multi-optional.  
Port:  
Displays the port number.  
Link Type:  
Displays the Link Type of the port. It can be reset on Port Config  
screen.  
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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  
LAG:  
Displays the LAG to which the port belongs.  
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 VLAN802.1Q VLANPort 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:  
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.  
Select:  
Port:  
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Select the Link Type from the pull-down list for the port.  
Link Type:  
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.  
PVID:  
LAG:  
Enter the PVID number of the port.  
Displays the LAG to which the port belongs.  
VLAN:  
Click the Detail button to view the information of the VLAN to  
which the port belongs.  
Click the Detail button to view the information of the corresponding VLAN  
Figure 6-6 View the Current VLAN of Port  
The following entries are displayed on this screen:  
VLAN of Port  
VLAN ID Select:  
Click the Select button to quick-select the corresponding entry  
based on the VLAN ID number you entered.  
Displays the ID number of VLAN.  
VLAN ID:  
Displays the user-defined description of VLAN.  
Allows you to remove the port from the current VLAN.  
VLAN Description:  
Operation:  
Configuration procedure:  
Step Operation  
Description  
1
Set the link type for Required. On the VLAN802.1Q VLANPort Config page, set  
port.  
the link type for the port basing on its connected device.  
2
Create VLAN.  
Required. On the VLAN802.1Q VLANVLAN 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.  
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3
4
Modify/View VLAN.  
Delete VLAN  
Optional. On the VLAN802.1Q VLANVLAN Config page,  
click the Edit/Detail button to modify/view the information of the  
corresponding VLAN.  
Optional. On the VLAN802.1Q VLANVLAN Config page,  
select the desired entry to delete the corresponding VLAN by  
clicking the Delete button.  
6.2 Application Example for 802.1Q VLAN  
Network Requirements  
Switch A is connecting to PC A and Server B;  
Switch B is connecting to PC B and Server A;  
PC A and Server A is in the same VLAN;  
PC B and Server B is in the same VLAN;  
PCs in the two VLANs cannot communicate with each other.  
Network Diagram  
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Configuration Procedure  
Configure Switch A  
Step  
Operation  
Description  
1
Configure  
the Required. On VLAN802.1Q VLANPort Config page, configure  
Link Type of the the link type of Port 2, Port 3 and Port 4 as ACCESS, TRUNK and  
ports  
ACCESS respectively  
2
3
Create VLAN10  
Required. On VLAN802.1Q VLANVLAN Config page, create a  
VLAN with its VLANID as 10, owning Port 2 and Port 3.  
Create VLAN20  
Required. On VLAN802.1Q VLANVLAN Config page, create a  
VLAN with its VLANID as 20, owning Port 3 and Port 4.  
Configure Switch B  
Step  
Operation  
Description  
1
Configure  
the Required. On VLAN802.1Q VLANPort Config page, configure  
Link Type of the the link type of Port 7, Port 6 and Port 8 as ACCESS, TRUNK and  
ports  
ACCESS respectively.  
2
3
Create VLAN10  
Required. On VLAN802.1Q VLANVLAN Config page, create a  
VLAN with its VLANID as 10, owning Port 6 and Port 8.  
Create VLAN20  
Required. On VLAN802.1Q VLANVLAN Config page, create a  
VLAN with its VLANID as 20, owning Port 6 and Port 7.  
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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 IDBridge 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 0~61440. 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.  
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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.  
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.  
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STP Generation  
In the beginning  
In the beginning, each switch regards itself as the root, and generates a configuration BPDU for  
each port on it as a root, with the root path cost being 0, the ID of the designated bridge being that  
of the switch, and the designated port being itself.  
Comparing BPDUs  
Each switch sends out configuration BPDUs and receives a configuration BPDU on one of its ports  
from another switch. The following table shows the comparing operations.  
Step Operation  
1
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
2
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.  
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  
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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.  
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 tress  
is called an instance. As well as STP, MSTP uses BPDUs to generate spanning tree. The only  
difference is that the BPDU for MSTP carry 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 TreeSTP ConfigSTP Config to load the following page.  
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Figure 7-4 STP Config  
The following entries are displayed on this screen:  
Global Config  
STP:  
Select Enable/Disable STP function globally on the switch.  
Select the desired STP version on the switch.  
Version:  
STP: Spanning Tree Protocol.  
RSTP: Rapid Spanning Tree Protocol.  
MSTP: Multiple Spanning Tree Protocol.  
Parameters Config  
CIST Priority:  
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.  
Hello Time  
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.  
Max Age:  
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.  
Forward Delay:  
TxHoldCount:  
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.  
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Max Hops:  
Note:  
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.  
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.  
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 TreeSTP ConfigSTP Summary to load the following page.  
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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 TreePort 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:  
Click the Select button to quick-select the corresponding port based  
on the port number you entered.  
Select:  
Port:  
Select the desired port for STP configuration. It is multi-optional.  
Displays the port number of the switch.  
Status:  
Priority:  
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:  
IntPath Cost:  
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.  
Edge Port:  
P2P Link:  
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.  
MCheck:  
Select Enable to perform MCheck operation on the port. Unchange  
means no MCheck operation.  
STP Version:  
Port Role:  
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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Designated Port: Indicates the port that forwards packets to a  
downstream network segment or switch.  
Master Port: Indicates the port that connects a MST region to the  
common root. The path from the master port to the common root  
is the shortest path between this MST region and the common  
root.  
Alternate Port: Indicates the port that can be a backup port of a  
root or master port.  
Backup Port: Indicates the port that is the backup port of a  
designated port.  
Disabled: Indicates the port that is not participating in the STP.  
Port Status:  
Displays the working status of the port.  
Forwarding: 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.  
LAG:  
Note:  
Displays the LAG number which the port belongs to.  
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 TreeMSTP InstanceRegion Config to load the following page.  
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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 TreeMSTP InstanceInstance Config to load the following page.  
Figure 7-8 Instance Config  
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The following entries are displayed on this screen:  
Instance Table  
Instance ID Select: Click the Select button to quick-select the corresponding Instance ID  
based on the ID number you entered.  
Select:  
Select the desired Instance ID for configuration. It is multi-optional.  
Displays Instance ID of the switch.  
Instance:  
Status:  
Select Enable/Disable the instance.  
Priority:  
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.  
VLAN ID:  
Clear:  
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:  
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.  
Instance ID:  
Note:  
Enter the corresponding instance ID.  
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.  
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 TreeMSTP InstanceInstance 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 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:  
Select the desired port to specify its priority and path cost. It is  
multi-optional.  
Port:  
Displays the port number of the switch.  
Priority:  
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:  
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.  
Port Role:  
Port Status:  
LAG:  
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.  
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Note:  
The port status of one port in different spanning tree instances can be different.  
Global configuration Procedure for Spanning Tree function:  
Step Operation  
Description  
Make clear roles the switches Preparation.  
play in spanning tree  
1
instances: root bridge or  
designated bridge  
2
Globally  
parameters  
configure  
MSTP Required. Enable Spanning Tree function on the switch  
and configure MSTP parameters on Spanning  
TreeSTP ConfigSTP Config page.  
3
4
Configure MSTP parameters Required. Configure MSTP parameters for ports on  
for ports  
Spanning TreePort ConfigPort Config page.  
Configure the MST region  
Required. Create MST region and configure the role the  
switch plays in the MST region on Spanning  
TreeMSTP InstanceRegion Config and Instance  
Config page.  
5
Configure MSTP parameters Optional. Configure different instances in the MST region  
for instance ports  
and configure MSTP parameters for instance ports on  
Spanning TreeMSTP InstanceInstance 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.  
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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  
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 attack 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 TreeSTP SecurityPort 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:  
Click the Select button to quick-select the corresponding port based  
on the port number you entered.  
Select:  
Select the desired port for port protect configuration. It is  
multi-optional.  
Port:  
Displays the port number of the switch.  
Loop Protect:  
Loop Protect is to prevent the loops in the network brought by  
recalculating STP because of link failures and network congestions.  
Root Protect:  
TC Protect:  
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:  
BPDU Protect is to prevent the edge port from being attacked by  
maliciously created BPDUs  
BPDU Filter:  
LAG:  
BPDU Filter is to prevent BPDUs flood in the STP network.  
Displays the LAG number which the port belongs to.  
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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.  
Choose the menu Spanning TreeSTP SecurityTC 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 VLAN01, 103 and 105 are transmitted in the STP with B as the root bridge. The  
data in VLAN02, 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  
1
Configure ports  
On VLAN802.1Q VLAN page, configure the link type  
of the related ports as Trunk, and add the ports to VLAN  
101 and VLAN 106. The detailed instructions can be  
found in the section 802.1Q VLAN.  
2
Enable STP function  
On Spanning TreeSTP ConfigSTP Config page,  
enable STP function and select MSTP version.  
On Spanning TreeSTP ConfigPort Config page,  
enable MSTP function for the port.  
3
4
Configure the region name and On Spanning TreeMSTP InstanceRegion Config  
the revision of MST region  
page, configure the region as TP-LINK and keep the  
default revision setting.  
Configure  
VLAN-to-Instance On Spanning TreeMSTP InstanceInstance  
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  
1
Configure ports  
On VLAN802.1Q VLAN page, configure the link type  
of the related ports as Trunk, and add the ports to VLAN  
101 and VLAN 106. The detailed instructions can be  
found in the section 802.1Q VLAN.  
2
Enable STP function  
On Spanning TreeSTP ConfigSTP Config page,  
enable STP function and select MSTP version.  
On Spanning TreeSTP ConfigPort Config page,  
enable MSTP function for the port.  
3
4
Configure the region name and On Spanning TreeMSTP InstanceRegion Config  
the revision of MST region  
page, configure the region as TP-LINK and keep the  
default revision setting.  
Configure  
VLAN-to-Instance On Spanning TreeMSTP InstanceInstance  
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
6
Configure switch B as the root On Spanning TreeMSTP InstanceInstance  
bridge of Instance 1  
Config page, configure the priority of Instance 1 to be 0.  
Configure switch  
B
as the On Spanning TreeMSTP InstanceInstance  
designated bridge of Instance 2 Config page, configure the priority of Instance 2 to be  
4096.  
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Configure Switch C:  
Step Operation  
Description  
1
Configure ports  
On VLAN802.1Q VLAN page, configure the link type  
of the related ports as Trunk, and add the ports to VLAN  
101 and VLAN 106. The detailed instructions can be  
found in the section 802.1Q VLAN.  
2
Enable STP function  
On Spanning TreeSTP ConfigSTP Config page,  
enable STP function and select MSTP version.  
On Spanning TreeSTP ConfigPort Config page,  
enable MSTP function for the port.  
3
4
Configure the region name and On Spanning TreeMSTP InstanceRegion Config  
the revision of MST region  
page, configure the region as TP-LINK and keep the  
default revision setting.  
Configure  
VLAN-to-Instance On Spanning TreeMSTP InstanceInstance  
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
6
Configure switch C as the root On Spanning TreeMSTP InstanceInstance  
bridge of Instance 1  
Config page, configure the priority of Instance 1 to be  
4096.  
Configure switch C as the root On Spanning TreeMSTP InstanceInstance  
bridge of Instance 2  
Config page, configure the priority of Instance 2 to be 0.  
Configure Switch D:  
Step Operation  
Description  
1
Configure ports  
On VLAN802.1Q VLAN page, configure the link type  
of the related ports as Trunk, and add the ports to VLAN  
101 and VLAN 106. The detailed instructions can be  
found in the section 802.1Q VLAN.  
2
Enable STP function  
On Spanning TreeSTP ConfigSTP Config page,  
enable STP function and select MSTP version.  
On Spanning TreeSTP ConfigPort Config page,  
enable MSTP function for the port.  
3
4
Configure the region name and On Spanning TreeMSTP InstanceRegion Config  
the revision of MST region  
page, configure the region as TP-LINK and keep the  
default revision setting.  
Configure  
VLAN-to-Instance On Spanning TreeMSTP InstanceInstance  
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.  
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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.  
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  
way as shown in Figure 8-1.  
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 sends 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  
1. Multicast IP Address:  
As specified by IANA (Internet Assigned Numbers Authority), Class D IP addresses are used as  
destination addresses of multicast packets. The multicast IP addresses range from  
224.0.0.0~239.255.255.255. The following table displays the range and description of several  
special multicast IP addresses.  
Multicast IP address range Description  
Reserved multicast addresses for routing protocols  
and other network protocols  
224.0.0.0224.0.0.255  
Addresses for video conferencing  
224.0.1.0224.0.1.255  
Local management multicast addresses, which are  
used in the local network only  
239.0.0.0239.255.255.255  
Table 8-1 Range of the special multicast IP  
2. Multicast MAC Address:  
When a unicast packet is transmitted in an Ethernet network, the destination MAC address is the  
MAC address of the receiver. When a multicast packet is transmitted in an Ethernet network, the  
destination is not a receiver but a group with uncertain number of members, so a multicast MAC  
address, a logical MAC address, is needed to be used as the destination address.  
As stipulated by IANA, the high-order 24 bits of a multicast MAC address begins with 01-00-5E  
while the low-order 23 bits of a multicast MAC address are the low-order 23 bits of the multicast IP  
address. The mapping relationship is described as 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 address.  
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.  
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VLAN ID  
Multicast IP  
Port  
Figure 8-3 Multicast Address Table  
IGMP Snooping  
In the network, the hosts apply to the near Router for joining (leaving) a multicast group by sending  
IGMP (Internet Group Management Protocol) messages. When the up-stream device forwards  
down the multicast data, the switch is responsible for sending them to the hosts. IGMP Snooping is  
a multicast control mechanism, which can be used on the switch for dynamic registration of the  
multicast group. The switch, running IGMP Snooping, manages and controls the multicast group via  
listening to and processing the IGMP messages transmitted between the hosts and the multicast  
router, thereby effectively prevent 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,  
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it will be added to the multicast address table with its member port time specified; if the receiving  
port is already a member port, its member port time will be directly reset.  
3. IGMP Leave Message  
The host, running IGMPv1, does not send IGMP leave message when leaving a multicast group,  
as a result, the switch 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 remove the whole multicast group and send IGMP leave message to the  
router.  
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 MulticastIGMP SnoopingSnooping 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:  
Select Enable/Disable IGMP Snooping function globally on the  
Switch.  
Unknown Multicast:  
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 MulticastIGMP SnoopingPort Config to load the following page.  
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Figure 8-5 Port Config  
The following entries are displayed on this screen:  
Port Config  
Port Select:  
Click the Select button to quick-select the corresponding port  
based on the port number you entered.  
Select:  
Select the desired port for IGMP Snooping feature configuration. It  
is multi-optional.  
Port:  
Displays the port of the Switch.  
IGMP Snooping:  
Fast Leave:  
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.  
LAG:  
Note:  
Displays the LAG number which the port belongs to.  
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 MulticastIGMP SnoopingVLAN 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:  
Enter the VLAN ID to enable IGMP Snooping for the desired  
VLAN.  
Router Port Time:  
Member Port Time:  
Leave Time:  
Specify the aging time of the router port. Within this time, if the  
switch doesn’t receive IGMP query message from the router port,  
it will consider this port is not a router port any more.  
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.  
Static Router Port:  
Select the static router port which is mainly used in the network  
with stable topology.  
VLAN Table  
VLAN ID Select:  
Click the Select button to quick-select the corresponding VLAN ID  
based on the ID number you entered.  
Select:  
Select the desired VLAN ID for configuration. It is multi-optional.  
Displays the VLAN ID.  
VLAN ID:  
Router Port Time:  
Member Port Time:  
Leave Time:  
Displays the router port time of the VLAN.  
Displays the member port time of the VLAN.  
Displays the leave time of the VLAN.  
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Router Port:  
Note:  
Displays the router port of the VLAN.  
The settings here will be invalid when multicast VLAN is enabled  
Configuration procedure:  
Step Operation  
Description  
Enable IGMP Snooping Required. Enable IGMP Snooping globally on the switch  
function and for the port on MulticastIGMP  
SnoopingSnooping Config and Port Config page.  
Configure the multicast Optional. Configure the multicast parameters for VLANs on  
1
2
parameters for VLANs  
MulticastIGMP SnoopingVLAN 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 MulticastIGMP SnoopingMulticast 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:  
Select Enable/Disable Multicast VLAN feature.  
Enter the VLAN ID of the multicast VLAN.  
Router Port Time:  
Specify the aging time of the router port. Within this time, if the  
switch doesn’t receive IGMP query message from the router port,  
it will consider this port is not a router port any more.  
Member Port Time:  
Leave Time:  
Specify the aging time of the member port. Within this time, if the  
switch doesn’t receive IGMP report message from the member  
port, it will consider this port is not a member port any more.  
Specify the interval between the switch receiving a leave message  
from a host, and the switch removing the host from the multicast  
groups.  
Router Ports:  
Note:  
Select the static router port which is mainly used in the network  
with stable topology.  
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  
1
2
Enable IGMP Snooping Required. Enable IGMP Snooping globally on the switch  
function  
and  
for  
the  
port  
on  
MulticastIGMP  
SnoopingSnooping Config and Port Config page.  
Create a multicast VLAN  
Required. Create a multicast VLAN and add all the member  
ports and router ports to the VLAN on the VLAN802.1Q  
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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3
4
Configure parameters for Optional. Enable and configure a multicast VLAN on the  
multicast VLAN  
MulticastIGMP SnoopingMulticast 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 MulticastIGMP SnoopingSnooping 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  
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Configuration Procedure  
Step Operation  
Description  
1
2
Create VLANs  
Create three VLANs with the VLAN ID 3, 4 and 5 respectively,  
and specify the description of VLAN3 as Multicast VLAN on  
VLAN802.1Q VLAN page.  
Configure ports  
On VLAN802.1Q 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 Enable IGMP Snooping function globally on MulticastIGMP  
Snooping function  
SnoopingSnooping Config page. Enable IGMP Snooping  
function for port 3, port4 and port 5 on MulticastIGMP  
SnoopingPort Config page.  
4
5
Enable  
VLAN  
Multicast Enable Multicast VLAN, configure the VLAN ID of a multicast  
VLAN as 3 and keep the other parameters as default on  
MulticastIGMP SnoopingMulticast VLAN page.  
Check Multicast VLAN 3-5 and Multicast VLAN 3 will be displayed in the IGMP  
Snooping Status table on the MulticastIGMP  
SnoopingSnooping 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 MulticastMulticast IPMulticast IP Table to load the following page.  
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Figure 8-8 Multicast IP Table  
The following entries are displayed on this screen:  
Search Option  
Multicast IP:  
VLAN ID:  
Port:  
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.  
Type:  
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:  
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.  
Forward Port  
Type:  
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 MulticastMulticast IPStatic Multicast IP to load the following page.  
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Figure 8-9 Static Multicast IP Table  
The following entries are displayed on this screen:  
Create Static Multicast  
Multicast IP:  
VLAN ID:  
Enter static multicast IP address.  
Enter the VLAN ID of the multicast IP.  
Enter the forward port of the multicast group.  
Forward Port:  
Search Option  
Search Option:  
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:  
Select the desired entry to delete the corresponding static  
multicast IP. It is multi-optional.  
Multicast IP:  
VLAN ID:  
Displays the multicast IP.  
Displays the VLAN ID of the multicast group.  
Displays the forward port of the multicast group.  
Forward Port:  
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.  
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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 MulticastMulticast FilterIP-Range to load the following page.  
Figure 8-10 Multicast Filter  
The following entries are displayed on this screen:  
Create IP-Range  
IP Range ID:  
Enter the IP-range ID.  
Start Multicast IP:  
End Multicast IP:  
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:  
Click the Select button to quick-select the corresponding IP-range  
ID based on the ID number you entered.  
Select:  
Select the desired entry to delete or modify the corresponding  
IP-range. It is multi-optional.  
IP-Range ID:  
Displays IP-range ID.  
Start Multicast IP:  
End Multicast IP:  
Displays start multicast IP of the IP-range.  
Displays end multicast IP of the IP-range.  
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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 MulticastMulticast FilterPort Filter to load the following page.  
Figure 8-11 Port Filter  
The following entries are displayed on this screen:  
Port Filter Config  
Port Select:  
Click the Select button to quick-select the corresponding port  
based on the port number you entered.  
Select:  
Select the desired port for multicast filtering. It is multi-optional.  
Displays the port number.  
Port:  
Filter:  
Select Enable/Disable multicast filtering feature on the port.  
Action Mode:  
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.  
Bound IP-Range (ID):  
Max Groups:  
Enter the IP-rang ID the port will be bound to.  
Specify the maximum number of multicast groups to prevent some  
ports taking up too much bandwidth.  
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LAG:  
Note:  
Displays the LAG number which the port belongs to.  
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.  
3. Up to 15 IP-Ranges can be bound to one port.  
Configuration Procedure:  
Step Operation  
Description  
1
Configure IP-Range  
Required. Configure IP-Range to be filtered on  
MulticastMulticast FilterIP-Range page.  
2
Configure multicast filter Optional. Configure multicast filter rules for ports on  
rules for ports  
MulticastMulticast FilterPort 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 MulticastPacket Statistics to load the following page.  
Figure 8-12 Packet Statistics  
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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.  
IGMP Statistics  
Port Select:  
Click the Select button to quick-select the corresponding port  
based on the port number you entered.  
Port:  
Displays the port number of the switch.  
Query Packet:  
Report Packet (V1):  
Report Packet (V2):  
Report Packet (V3):  
Leave Packet:  
Error Packet:  
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.  
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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.  
1. Port Priority  
Port priority is a priority level of the port. After port priority is configured, the data stream will be mapped  
to the egress queues directly according to the priority level of the port.  
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2. 802.1P Priority  
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.  
3. DSCP Priority  
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 if 8021.1P Priority mode is enabled; the untagged non-IP datagram are mapped  
based on port priority mode.  
Schedule Mode  
When the network is congested, the problem that many packets compete for resources must be  
solved, usually in the way of queue scheduling. The switch implements 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.  
1. SP-Mode: Strict-Priority Mode. In this mode, the queue with higher priority will occupy the  
whole bandwidth. Packets in the queue with lower priority are sent only when the queue with  
higher priority is empty. The switch has 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.  
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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.  
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The QoS module is mainly for traffic control and priority configuration, including three submenus:  
DiffServ and Bandwidth Control.  
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 TC0, TC1, TC2 and TC3.  
The DiffServ function can be implemented on Port Priority, 802.1P Priority, DSCP Priority and  
Schedule Mode pages.  
9.1.1 Port Priority  
On this page you can configure the port priority.  
Choose the menu QoSDiffServPort 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:  
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.  
Priority:  
LAG:  
Displays the LAG number which the port belongs to.  
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Note:  
To complete QoS function configuration, you have to go to the Schedule Mode page to select a  
schedule mode after the configuration is finished on this page.  
Configuration Procedure:  
Step Operation  
Description  
1
Log on to the Port Priority  
page  
2
Select the desired ports for Select the desired ports. It is multi-optional.  
configuration  
3
4
Select the port priority  
Select a schedule mode  
Required. Select a priority from TC0 to TC3.  
Required. Log on to the Schedule Mode page to  
select a schedule mode.  
9.1.2 802.1P Priority  
On this page you can configure 802.1P priority. 802.1P gives the Pri field in 802.1Q tag a  
recommended definition. This field is used to divide packets into 8 priorities. When 802.1P Priority is  
enabled, the packets with 802.1Q tag are mapped to different priority levels based on 802.1P priority  
mode. The untagged packets are mapped based on port priority mode.  
Choose the menu QoSDiffServ802.1P Priority to load the following page.  
Figure 9-7 802.1P Priority  
The following entries are displayed on this screen:  
802.1P Priority Config  
802.1P Priority:  
Select Enable/Disable 802.1P Priority.  
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Priority Level  
Tag-id/CoS-id:  
Indicates the precedence level defined by IEEE802.1P and the  
CoS ID  
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  
Note:  
To complete QoS function configuration, you have to go to the Schedule Mode page to select a  
schedule mode after the configuration is finished on this page.  
Configuration Procedure:  
Step Operation  
Description  
1
2
3
4
Log on to the 802.1P Priority  
page  
Enable  
function  
802.1P  
priority Required. By default, the 802.1P priority function is  
disabled.  
Map the 802.1P priority tag to Required. Select 802.1P priority tag and the  
the priority level  
corresponding priority level.  
Select a schedule mode  
Required. Log on to the Schedule Mode page to  
select a schedule mode.  
9.1.3 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 QoSDiffServDSCP Priority to load the following page.  
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Figure 9-8 DSCP Priority  
The following entries are displayed on this screen:  
DSCP Priority Config  
DSCP Priority:  
Priority Level  
DSCP:  
Select Enable or Disable DSCP Priority.  
Indicates the priority determined by the DS region of IP datagram.  
It ranges from 0 to 63.  
Priority Level:  
Indicates the priority level the packets with tag are mapped to. The  
priority levels are labeled as TC0, TC1, TC2 and TC3.  
Note:  
To complete QoS function configuration, you have to go to the Schedule Mode page to select a  
schedule mode after the configuration is finished on this page.  
Configuration procedure:  
Step Operation  
Description  
1
Log on to the DSCP Priority  
page  
2
Enable DP priority function  
Required. By default, the DSCP priority function is  
disabled.  
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3
4
Map the DSCP priority to the Required. Select DSCP priority and the corresponding  
priority level  
priority level.  
Select a schedule mode  
Required. Log on to the Schedule Mode page to  
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 QoSDiffServSchedule Mode to load the following page.  
Figure 9-9 Schedule Mode  
The following entries are displayed on this screen:  
Schedule Mode Config  
SP-Mode:  
Strict-Priority Mode. In this mode, the queue with higher priority  
will occupy the whole bandwidth. Packets in the queue with lower  
priority are sent only when the queue with higher priority is empty.  
WRR-Mode:  
Weight Round Robin Mode. In this mode, packets in all the  
queues are sent in order based on the weight value for each  
queue. The weight value ratio of TC0, TC1, TC2 and TC3 is  
1:2:4:8.  
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.  
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.  
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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 QoSBandwidth ControlRate Limit to load the following page.  
Figure 9-10 Rate Limit  
The following entries are displayed on this screen:  
Rate Limit Config  
Port Select:  
Click the Select button to quick-select the corresponding port  
based on the port number you entered.  
Select:  
Select the desired port for Rate configuration. It is multi-optional.  
Displays the port number of the Switch.  
Port:  
Ingress Rate(Kbps):  
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.  
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Egress Rate(Kbps):  
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.  
LAG:  
Note:  
Displays the LAG number which the port belongs to.  
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 1023Kbps 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 QoSBandwidth ControlStorm Control to load the following page.  
Figure 9-11 Storm Control  
The following entries are displayed on this screen:  
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Storm Control Config  
Port Select:  
Click the Select button to quick-select the corresponding port  
based on the port number you entered.  
Select:  
Select the desired port for Storm Control configuration. It is  
multi-optional.  
Port:  
Displays the port number of the Switch.  
Broadcast Rate (bps):  
Multicast Rate (bps):  
UL-Frame Rate (bps):  
LAG:  
Enable/Disable broadcast control feature for the port.  
Enable/Disable multicast control feature for the port.  
Enable/Disable UL-Frame control feature 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.  
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Chapter 10 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 restarting the device.  
MIB: MIB is the set of the managed objects. MIB defines a few attributes of the managed objects,  
including the names, the access rights, and the data types. Every SNMP Agent has its own MIB.  
The SNMP Management station can read/write the MIB objects basing on its management right.  
SNMP Management Station is the manager of SNMP network while SNMP Agent is the managed  
object. The information between SNMP Management Station and SNMP Agent are exchanged  
through SNMP (Simple Network Management Protocol). The relationship among SNMP  
Management Station, SNMP Agent and MIB is illustrated in the following figure.  
Figure 10-1 Relationship among SNMP Network Elements  
SNMP Versions  
This switch supports SNMP v3, and is compatible with SNMP 1 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: Basing on SNMP v1 and SNMP v2c, SNMP v3 extremely enhances the security and  
manageability. It adopts VACM (View-based Access Control Model) and USM (User-Based  
Security Model) authentication. The user can configure the authentication and the encryption  
functions. The authentication function is to limit the access of the illegal user by authenticating the  
senders of packets. Meanwhile, the encryption function is used to encrypt the packets transmitted  
between SNMP Management Station and SNMP Agent so as to prevent any information being  
stolen. The multiple combinations of authentication function and encryption function can  
guarantee a more reliable communication between SNMP Management station and SNMP Agent.  
MIB Introduction  
To uniquely identify the management objects of the device in SNMP messages, SNMP adopts the  
hierarchical architecture to identify the managed objects. It is like a tree, and each tree node  
represents a managed object, as shown in the following figure. Thus the object can be identified  
with the unique path starting from the root and indicated by a string of numbers. The number string  
is the Object Identifier of the managed object. In the following figure, the OID of the managed  
object B is {1.2.1.1}. While the OID of the managed object A is {1.2.1.1.5}.  
Figure 10-2 Architecture of the MIB tree  
SNMP Configuration Outline  
1. Create View  
The SNMP View is created for the SNMP Management Station to manage MIB objects. The  
managed object, uniquely identified by OID, can be set to under or out of the management of  
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 a 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.  
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3. Create SNMP User  
The User is configured in a SNMP Group can manage the switch via the client program on  
management station. The specified User Name and the Auth/Privacy Password are used for  
SNMP Management Station to access the SNMP Agent, functioning as the password.  
SNMP module is used to configure the SNMP function of the switch, including three submenus:  
SNMP Config, Notification and RMON.  
10.1 SNMP Config  
The SNMP Config can be implemented on the Global Config, SNMP View, SNMP Group,  
SNMP User and SNMP Community pages.  
10.1.1 Global Config  
To enable SNMP function, please configure the SNMP function globally on this page.  
Choose the menu SNMPSNMP ConfigGlobal Config to load the following page.  
Figure 10-3 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.  
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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 informs from Switch.  
Note:  
The amount of Engine ID characters must be even.  
10.1.2 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 SNMPSNMP ConfigSNMP View to load the following page.  
Figure 10-4 SNMP View  
The following entries are displayed on this screen:  
View Config  
View Name:  
Give a name to the View for identification. Each View can  
include several entries with the same name.  
MIB Object ID:  
View Type:  
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.  
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View Table  
Select:  
Select the desired entry to delete the corresponding view. All  
the entries of a View will be deleted together.  
View Name:  
View Type:  
Displays the name of the View entry.  
Displays the type of the View entry.  
Displays the OID of the View entry.  
MIB Object ID:  
10.1.3 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 SNMPSNMP ConfigSNMP Group to load the following page.  
Figure 10-5 SNMP Group  
The following entries are displayed on this screen:  
Group Config  
Group Name:  
Enter the SNMP Group name. The Group Name, Security Model  
and Security Level compose the identifier of the SNMP Group.  
These three items of the Users in one group should be the same.  
Security Model:  
Select the Security Model for the SNMP Group.  
v1: SNMPv1 is defined for the group. In this model, the  
Community Name is used for authentication. SNMP v1 can be  
configured on the SNMP Community page directly.  
v2c: SNMPv2c is defined for the group. In this model, the  
Community Name is used for authentication. SNMP v2c can be  
configured on the SNMP Community page directly.  
v3: SNMPv3 is defined for the group. In this model, the USM  
mechanism is used for authentication. If SNMPv3 is enabled,  
the Security Level field is enabled for configuration.  
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Security Level:  
Select the Security Level for the SNMP v3 Group.  
noAuthNoPriv: No authentication and no privacy security  
levels are used.  
authNoPriv: Only the authentication security level is used.  
authPriv: Both the authentication and the privacy security  
levels are used.  
Read View:  
Write View:  
Select the View to be the Read View. The management access is  
restricted to read-only, and changes cannot be made to the  
assigned SNMP View.  
Select the View to be the Write View. The management access is  
writing only and changes can be made to the assigned SNMP  
View. The View defined both as the Read View and the Write View  
can be read and modified.  
Notify View:  
Select the View to be the Notify View. The management station  
can receive notification messages of the assigned SNMP view  
generated by the Switch's SNMP agent.  
Group Table  
Select:  
Select the desired entry to delete the corresponding group. It's  
multi-optional.  
Group Name:  
Security Model:  
Security Level:  
Read View:  
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.  
Write View:  
Notify View:  
Operation:  
Click the Edit button to modify the Views in the entry and click the  
Modify button to apply.  
Note:  
Every Group should contain a Read View. The default Read View is viewDefault.  
10.1.4 SNMP User  
The User in a 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 SNMPSNMP ConfigSNMP User to load the following page.  
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Figure 10-6 SNMP User  
The following entries are displayed on this screen:  
User Config  
User Name:  
User Type:  
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.  
Group Name:  
Select the Group Name of the User. The User is classified to  
the corresponding Group according to its Group Name,  
Security Model and Security Level.  
Security Model:  
Security Level:  
Auth Mode:  
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.  
Auth Password:  
Privacy 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.  
Privacy Password:  
Enter the Privacy Password.  
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User Table  
Select:  
Select the desired entry to delete the corresponding User. It is  
multi-optional.  
User Name:  
User Type:  
Displays the name of the User.  
Displays the User Type.  
Group Name:  
Security Model:  
Security Level:  
Auth Mode:  
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.  
Privacy Mode:  
Operation:  
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.  
10.1.5 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 SNMPSNMP ConfigSNMP Community to load the following page.  
Figure 10-7 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.  
MIB View:  
Select the MIB View for the community to access.  
Community Table  
Select:  
Select the desired entry to delete the corresponding Community. It  
is multi-optional.  
Community Name:  
Access:  
Displays the Community Name here.  
Displays the right of the Community to access the View.  
Displays the Views which the Community can access.  
MIB View:  
Operation:  
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  
Description  
1
Enable SNMP function globally.  
Required. On the SNMPSNMP ConfigGlobal  
Config page, enable SNMP function globally.  
2
Create SNMP View.  
Create SNMP Group.  
Create SNMP User.  
Required. On the SNMPSNMP ConfigSNMP  
View page, create SNMP View of the management  
agent. The default View Name is viewDefault and the  
default OID is 1.  
3
4
Required. On the SNMPSNMP ConfigSNMP  
Group page, create SNMP Group for SNMPv3 and  
specify SNMP Views with various access levels for  
SNMP Group.  
Required. On the SNMPSNMP ConfigSNMP  
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  
Description  
1
Enable SNMP function globally.  
Required. On the SNMPSNMP ConfigGlobal  
Config page, enable SNMP function globally.  
2
Create SNMP View.  
Required. On the SNMPSNMP ConfigSNMP  
View page, create SNMP View of the management  
agent. The default View Name is viewDefault and the  
default OID is 1.  
3
Create  
SNMP Required alternatively.  
Community  
directly.  
Create SNMP Community directly.  
On the SNMPSNMP ConfigSNMP  
Community page, create SNMP Community  
based on SNMP v1 and SNMP v2c.  
Create SNMP Group and SNMP User.  
Configure  
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.  
access level  
for the User.  
Create  
Group and SNMP  
User.  
SNMP  
10.2 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.  
InformInform 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 has a higher security than the Trap type, which is  
employed on SNMPv3.  
On this page, you can configure the notification function of SNMP.  
Choose the menu SNMPNotificationNotification to load the following page.  
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Figure 10-8 Notification Config  
The following entries are displayed on this screen:  
Create Notification  
IP Address:  
Enter the IP Address of the management Host.  
UDP Port:  
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.  
User:  
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.  
Security Model:  
Security Level:  
noAuthNoPriv: No authentication and no privacy security  
level are used.  
authNoPriv: Only the authentication security level is used.  
authPriv: Both the authentication and the privacy security  
levels are used.  
Type:  
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.  
Retry:  
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.  
Timeout:  
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:  
Select the desired entry to delete the corresponding  
management station.  
IP Address:  
UDP Port:  
User:  
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.  
Security Model:  
Security Level:  
Type:  
Timeout:  
Displays the maximum time for the switch to wait for the  
response from the management station before resending a  
request.  
Retry:  
Displays the amount of times the switch resends an inform  
request.  
Operation:  
Click the Edit button to modify the corresponding entry and  
click the Modify button to apply.  
10.3 RMON  
RMON (Remote Monitoring) basing on SNMP (Simple Network Management Protocol)  
architecture, functions to monitor the network. RMON is currently a commonly used network  
management standard defined by Internet Engineering Task Force (IETF), which is mainly used to  
monitor the data traffic across a network segment or even the entire network so as to enable the  
network administrator to take the protection measures in time to avoid any network malfunction. In  
addition, RMON MIB records network statistics information of network performance and  
malfunction periodically, based on which the management station can monitor network at any time  
effectively. RMON is helpful for network administrator to manage the large-scale network since it  
reduces the communication traffic between management station and managed agent.  
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.  
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Alarm Group  
Alarm Group is configured to monitor the specific alarm variables. When the  
value of a monitored variable exceeds the threshold, an alarm event is  
generated, which triggers the switch to act in the set way.  
The RMON Groups can be configured on the History Control, Event Config and Alarm Config  
pages.  
10.3.1 History Control  
On this page, you can configure the History Group for RMON.  
Choose the menu SNMPRMONHistory Control to load the following page.  
Figure 10-9 History Control  
The following entries are displayed on this screen:  
History Control Table  
Select:  
Select the desired entry for configuration.  
Index:  
Displays the index number of the entry.  
Port:  
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.  
Interval:  
Owner:  
Status:  
10.3.2 Event Config  
On this page, you can configure the RMON events.  
Choose the menu SNMPRMONEvent Config to load the following page.  
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Figure 10-10 Event Config  
The following entries are displayed on this screen:  
Event Table  
Select:  
Index:  
Select the desired entry for configuration.  
Displays the index number of the entry.  
User:  
Enter the name of the User or the community to which the  
event belongs.  
Description:  
Type:  
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.  
Owner:  
Status:  
Enter the name of the device or user that defined the entry.  
Select Enable/Disable the corresponding event entry.  
10.3.3 Alarm Config  
On this page, you can configure Statistic Group and Alarm Group for RMON.  
Choose the menu SNMPRMONAlarm Config to load the following page.  
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Figure 10-11 Alarm Config  
The following entries are displayed on this screen:  
Alarm Table  
Select:  
Select the desired entry for configuration.  
Displays the index number of the entry.  
Index:  
Variable:  
Port:  
Select the alarm variables form the pull-sown list.  
Select the port on which the Alarm entry acts.  
Sample Type:  
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.  
Rising Threshold:  
Rising Event:  
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.  
Falling Threshold:  
Falling Event:  
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.  
Alarm Type:  
Specify the type of the alarm.  
All: The alarm event will be triggered either the sampled  
value exceeds the Rise Hold or is under the Fall Hold.  
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 11 Maintenance  
Maintenance module, assembling the commonly used system tools to manage the switch,  
provides the convenient method to locate and solve the network problem.  
1System Monitor: Monitor the utilization status of the memory and the CPU of switch.  
2Log: View the configuration parameters of the switch and find out the errors via the Logs.  
3Cable Test: Test the connection status of the cable to locate and diagnose the trouble spot  
of the network.  
4Loopback: Test whether the ports of the switch and its peer device are available.  
5Network Diagnose: Test whether the destination device is reachable and detect the route  
hops from the switch to the destination device.  
11.1 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.  
11.1.1 CPU Monitor  
Choose the menu MaintenanceSystem MonitorCPU Monitor to load the following page.  
Figure 11-1 CPU Monitor  
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Click the Monitor button to enable the switch to monitor and display its CPU utilization rate every  
four seconds.  
11.1.2 Memory Monitor  
Choose the menu MaintenanceSystem MonitorMemory Monitor to load the following page.  
Figure 11-2 Memory Monitor  
Click the Monitor button to enable the switch to monitor and display its Memory utilization rate  
every four seconds.  
11.2 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  
The system is unusable.  
emergencies  
0
1
2
3
4
Action must be taken immediately.  
Critical conditions  
alerts  
critical  
errors  
Error conditions  
Warnings conditions  
warnings  
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Normal but significant conditions  
Informational messages  
Debug-level messages  
notifications  
informational  
debugging  
5
6
7
Table 11-1 Log Level  
The Log function is implemented on the Log Table, Local Log, Remote Log and Backup Log  
pages.  
11.2.1 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 MaintenanceLogLog Table to load the following page.  
Figure 11-3 Log Table  
The following entries are displayed on this screen:  
Log Info  
Index:  
Time:  
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.  
Module:  
Severity:  
Content:  
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.  
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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.  
11.2.2 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_4 are saved in log file meanwhile. On this page,  
you can set the output channel for logs.  
Choose the menu MaintenanceLogLocal Log to load the following page.  
Figure 11-4 Local Log  
The following entries are displayed on this screen:  
Local Log Config  
Select:  
Select the desired entry to configure the corresponding local log.  
Log Buffer:  
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.  
Log File:  
Severity:  
Status:  
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.  
11.2.3 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 MaintenanceLogRemote Log to load the following page.  
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Figure 11-5 Log Host  
The following entries are displayed on this screen:  
Log Host  
Index:  
Displays the index of the log host. The switch supports 4 log  
hosts.  
Host IP:  
Configure the IP for the log host.  
UDP Port:  
Displays the UDP port used for receiving/sending log  
information. Here we use the standard port 514.  
Severity:  
Specify the severity level of the log information sent to each log  
host. Only the log with the same or smaller severity level value  
will be sent to the corresponding log host.  
Status:  
Note:  
Enable/Disable the log host.  
The Log Server software is not provided. If necessary, please download it on the Internet.  
11.2.4 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 MaintenanceLogBackup Log to load the following page.  
Figure 11-6 Backup Log  
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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.  
11.3 Device Diagnose  
This switch provides Cable Test and Loopback functions for device diagnose.  
11.3.1 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 MaintenanceDevice DiagnoseCable Test to load the following page.  
Figure 11-7 Cable Test  
The following entries are displayed on this screen:  
Cable Test  
Port:  
Select the port for cable testing.  
Displays the Pair number.  
Pair:  
Status:  
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.  
Length:  
Error:  
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.  
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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.  
11.3.2 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 MaintenanceDevice DiagnoseLoopback to load the following page.  
Figure 11-8 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.  
11.4 Network Diagnose  
This switch provides Ping test and Tracert test functions for network diagnose.  
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11.4.1 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.  
Choose the menu MaintenanceNetwork DiagnosePing to load the following page.  
Figure 11-9 Ping  
The following entries are displayed on this screen:  
Ping Config  
Destination IP:  
Ping Times:  
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.  
Data Size:  
Interval:  
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.  
11.4.2 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 MaintenanceNetwork DiagnoseTracert to load the following page.  
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Figure 11-10Tracert  
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.  
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Appendix A: Specifications  
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  
Standards  
IEEE802.1p Priority  
IEEE802.1q VLAN Bridge  
Ethernet: 10Mbps HD20Mbps FD  
Transmission Rate  
Fast Ethernet: 100Mbps HD200Mbps FD  
Gigabit Ethernet: 2000Mbps FD  
10Base-T: UTP/STP of Cat. 3 or above  
100Base-TX: UTP/STP of Cat. 5 or above  
Transmission Medium  
100Base-FX: MMF or SMF SFP Module (Optional)  
1000Base-T: 4-pair UTP (100m) of Cat. 5, Cat. 5e, Cat. 6  
1000Base-X: MMF or SMF SFP Module (Optional)  
PowerSystem10/100M LEDs1000M LEDs  
LED  
Transmission Method  
Store and Forward  
10BASE-T14881pps/port  
Packets Forwarding Rate 100BASE-TX148810pps/port  
1000Base-T1488095pps/port  
Operating Temperature: 0~ 40℃  
Operating  
Storage Temperature: -40~ 70℃  
Environment  
Operating Humidity: 10% ~ 90% RH Non-condensing  
Storage Humidity: 5% ~ 90% RH Non-condensing  
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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. Configure TCP/IP component  
1) On the Windows taskbar, click the Start button, and then click Control Panel.  
2) Click the Network and Internet Connections 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).  
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Figure B-2  
5) The following TCP/IP Properties window will display and the IP Address tab is open on  
this window by default.  
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Figure B-3  
6) Select Use the following IP address. 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.  
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Appendix C: 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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