L3 Protocols
Last updated
Last updated
Internet Group Management Protocol (IGMP) Snooping allows a switch to forward multicast traffic intelligently. Multicasting is used to support real-time applications such as video conferencing or streaming audio. A multicast server does not have to establish a separate connection with each client. It merely broadcasts its service to the network, and any host that wishes to receive the multicast register with their local multicast switch.
A multicast group is a group of end nodes that want to receive multicast packets from a multicast application. After joining a multicast group, a host node must continue to periodically issue reports to remain a member. Any multicast packets belonging to that multicast group are then forwarded by the switch from the port.
A switch supporting IGMP Snooping can passively snoop on IGMP Query, Report, and Leave packets transferred between IP Multicast switches and IP Multicast hosts to determine the IP Multicast group membership. IGMP Snooping checks IGMP packets passing through the network and configures multicasting accordingly. Based on the IGMP query and report messages, the switch forwards traffic only to the ports that request the multicast traffic. It enables the switch to forward packets of multicast groups to those ports that have validated host nodes. The switch can also limit flooding of traffic to IGMP designated ports. This improves network performance by restricting the multicast packets only to switch ports where host nodes are located. IGMP Snooping significantly reduces overall Multicast traffic passing through your switch. Without IGMP Snooping, Multicast traffic is treated in the same manner as a broadcast transmission, which forwards packets to all ports on the network.
IGMPv1
Defined in RFC 1112. An explicit join message is sent to the switch, but a timeout is used to determine when hosts leave a group.
IGMPv2
Defined in RFC 2236. Adds an explicit leave message to the join message so that the switch can more easily determine when a group has no interested listeners on a LAN.
IGMPv3
Defined in RFC 3376. Support for a single source of content for a multicast group.
Click to enable or disable the IGMP Snooping feature for the switch. Next, select whether you wish to use V2 or V3. Finally, select whether you wish to enable or disable the Report Suppression feature for the switch.
Items
Descriptions
Status
Select to enable or disable IGMP Snooping on the switch. The switch snoops all IGMP packets it receives to determine which segments should receive packets directed to the group address when enabled. The default setting is: Disabled.
Report Suppression
Select whether Report Suppression is Enabled or Disabled for IGMP Snooping. The Report Suppression feature limits the amount of membership reports the member sends to multicast capable routers.
Click Apply to update the system settings.
Review or configure Fast leave option per switch port.
Use the IGMP Snooping VLAN Settings to configure IGMP Snooping settings for VLANs on the system. The switch performs IGMP Snooping on VLANs that send IGMP packets. You can specify the VLANs that IGMP Snooping should be performed on. Choose from the drop-down box whether to enable or disable IGMP Snooping. Next, choose to enable or disable Fast Leave for the VLAN ID.
Items
Descriptions
VLAN ID
Displays the VLAN ID.
IGMP Snooping Status
Enables or disables the IGMP Snooping feature for the specified VLAN ID.
Version
Select the IGMP version you wish to use. If an IGMP packet received by the interface has a version higher than the specified version, this packet will be dropped.
If Fast Leave is not used, a multicast querier will send a GS-query message when an IGMPv2/v3 group leave message is received. The querier stops forwarding traffic for that group only if no host replies to the query within the specified timeout period. If Fast Leave is enabled, the switch assumes that only one host is connected to the port. Therefore, Fast Leave should only be enabled on a port if it is connected to only one IGMP-enabled device.
Fast Leave is supported only with IGMPv2 or IGMPv3 Snooping when IGMP Snooping is enabled. Fast Leave does not apply to a port if the switch has learned that a multicast querier is attached to it.
Fast Leave can improve bandwidth usage for a network which frequently experiences many IGMP host add and leave requests.
IGMP Snooping requires that one central switch to periodically query all end devices on the network to announce their multicast memberships and this central device is the IGMP querier. The snooping switch sends out periodic queries with a time interval equal to the configured querier query interval. The IGMP query keeps the switch updated with the current multicast group membership information. If the switch does not receive the updated membership information, then it will stop forwarding multicasts to specified VLANs.
Items
Descriptions
VLAN ID
Displays the VLAN ID.
Querier State
Select whether to enable or disable the IGMP querier state for the specified VLAN ID.
A querier can periodically ask their hosts if they wish to receive multicast traffic. The querier feature will check whether hosts wish to receive multicast traffic when enabled. An elected querier will assume the role of querying the LAN for group members and then propagate the service requests onto any upstream multicast switch to ensure that it will continue to receive the multicast service. This feature is only supported for IGMPv1 and v2 snooping.
Querier Version
Enter the version of IGMP packet that will be sent by this port. If an IGMP packet received by the port has a version higher than the specified version, this packet will be dropped.
Querier Status
Display the querier status.
Interval
Enter the amount of time in seconds between general query transmissions. The default is 125 seconds.
Max Response Interval
Enter the maximum response time used in the queries that are sent by the snooping querier. The default is 10 seconds.
Startup Query Counter
Enter the number of the startup query counter.
Startup Query Interval
Specify the Startup Query Interval.
The Group List displays VLAN ID, group IP address, and members port in the IGMP Snooping list.
The Router Settings shows the learned multicast router attached port if the port is active and a member of the VLAN. Select the VLAN ID you would like to configure and enter the Static and Forbidden ports for the specified VLAN IDs. All IGMP packets snooped by the switch will be forwarded to the multicast router reachable from the port.
Items
Descriptions
VLAN ID
Displays the VLAN ID.
Dynamic Port List
Displays router ports that have been dynamically configured.
Static Port list
Designates a range of ports as being connected to multicast-enabled routers. Ensures that all the packets will reach the multicast-enabled router.
Forbidden Port List
Designates a range of ports as being disconnected to multicast-enabled routers. Ensures that the forbidden router port will not propagate routing packets out.
Multicast Listener Discovery (MLD) Snooping operates on the IPv6 traffic level for discovering multicast listeners on a directly attached port and performs a similar function to IGMP Snooping for IPv4. MLD snooping allows the switch to examine MLD packets and make forwarding decisions based on content. MLD Snooping limits IPv6 multicast traffic by dynamically configuring the switch port so that multicast traffic is forwarded only to those ports that wish to receive it. This reduces the flooding of IPv6 multicast packets in the specified VLANs. Both IGMP and MLD Snooping can be active at the same time.
Item
Description
Status
Select to Enable or Disable MLD Snooping on the switch. The switch
snoops all MLD packets it receives to determine which segments should receive packets directed to the group address when enabled.
Mode
Select the MLD mode you wish to use either IP or MAC mode.
Report
Suppression
The report suppression feature limits the amount of membership reports the member sends to multicast capable routers.
Click Apply to update the system settings.
If the Fast Leave feature is not used, a multicast querier will send a GS-query message when an MLD group leave message is received. The querier stops forwarding traffic for that group only if no host replies to the query within the specified timeout period. If Fast Leave is enabled, the switch assumes that only one host is connected to the port. Therefore, Fast Leave should only be enabled on a port if it is connected to only one MLD-enabled device.
Fast Leave does not apply to a port if the switch has learned that a multicast querier is attached to it. Fast Leave can improve bandwidth usage for a network which frequently experiences many MLD host add and leave requests.
Item
Description
VLAN ID
Displays the VLAN ID.
MLD Snooping Status
Select to enable or disable the MLD snooping feature for the specified VLAN ID.
Version
Select the MLD version you wish to use. If an MLD packet received by the interface has a version higher than the specified version, this packet will be dropped.
Fast Leave
Enables or disables the MLD snooping Fast Leave feature for the specified VLAN ID. Enabling this feature allows the switch to immediately remove the Layer 2 LAN port from its forwarding table entry upon receiving an MLD leave message without first sending out an MLD group-specific (GS) query to the port.
Select from the drop-down list whether to enable or disable MLD Snooping. Next, select to enable or disable Fast Leave for the specified VLAN ID.
IGMP Snooping requires that one central switch to periodically query all end devices on the network to announce their multicast memberships and this central device is the IGMP querier. The snooping switch sends out periodic queries with a time interval equal to the configured querier query interval. The IGMP query keeps the switch updated with the current multicast group membership information. If the switch does not receive the updated membership information, then it will stop forwarding multicasts to specified VLANs.
Items
Descriptions
VLAN ID
Displays the VLAN ID.
Querier State
Select whether to enable or disable the IGMP querier state for the specified VLAN ID.
A querier can periodically ask their hosts if they wish to receive multicast traffic. The querier feature will check whether hosts wish to receive multicast traffic when enabled. An elected querier will assume the role of querying the LAN for group members and then propagate the service requests onto any upstream multicast switch to ensure that it will continue to receive the multicast service. This feature is only supported for IGMPv1 and v2 snooping.
Querier Status
Display the querier status.
Interval
Enter the amount of time in seconds between general query transmissions. The default is 125 seconds.
The Group List displays the VLAN ID, Group address, and member ports in the MLD Snooping List.
The Router Settings feature shows the learned multicast router attached port if the port is active and a member of the VLAN. Select the VLAN ID you would like to configure and enter the static and forbidden ports for the specified VLAN IDs that are utilizing MLD Snooping. All MLD packets snooped by the switch will be forwarded to the multicast router reachable from the port.
Item
Description
VLAN ID
Displays the VLAN ID.
Dynamic Port List
Displays router ports that have been dynamically configured.
Static Port List
Designates a range of ports as being connected to multicast-enabled routers. Ensure that all the packets will reach the multicast-enabled router.
Forbidden Port List
Designates a range of ports as being disconnected to multicast-enabled routers. Ensures that the forbidden router port will not propagate routing packets out.
This feature provides an extra layer of security by filtering untrusted DHCP messages where users can specify authorized DHCP servers for the networks and connect to the switch's trusted ports to serve underlying clients on this switch.
Items
Descriptions
DHCP Snooping Status
Select to enable or disable the DHCP Snooping feature.
MAC Verify
Select to enable or disable the MAC address verification feature.
This page lists the VLANs configured on the switch with DHCP Snooping default disabled.
Users can click Edit button to enable DHCP snooping on a specific VLAN.
Switch ports can be configured as either trusted or untrusted ports, respectively.
Choose "Enabled" and click the Apply button to activate this feature.
Specify the DHCP server's IP address to be relayed.
Static route is a routing type in which network administrators can configure the routes into the routing table and it's used by the network device to send packets to a destination network via a specific IPv4 or IPv6 route/gateway.
Click the Apply button to accept the changes or the Cancel button to discard them.VLAN Settings
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
Click the Apply button to accept the changes or the Cancel button to discard them.
