Tp-Link T2600G-28MPS (TL-SG3424P) [160/379] Snooping config

3. Member Leave Message

The host will send IGMP leave message when leaving a multicast group to inform the router of

its leaving.

When Immediate Leave is not enabled in a VLAN and a leave message is received on a port of

this VLAN, the switch will generate Multicast-Address-Specific Queries (MASQs) on this port to

check if there are other members in this multicast group. The user can control when a port

membership is removed for an existing address in terms of the number and interval of MASQs.

If there is no Report message received from this port during the switch maximum response

time, the port on which the MASQ was sent is deleted from the multicast group. If the deleted

port is the last member of the multicast group, the multicast group is also deleted. The switch

will send leave message to the router ports of the VLAN.

In IPv4，Layer 2 switches can use IGMP Snooping to limit the flooding of multicast traffic by

dynamically configuring Layer 2 interfaces so that IPv4 multicast data is selectively forwarded

to a list of ports that want to receive the data. This list is constructed by snooping IPv4

multicast control packets.

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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.

Last Listener Query Interval: The interval between the switch sends out MASQs.

Last Listener Query Count: The number of MASQs that the switch sends before aging out a

multicast address when there is no IGMP report response.

The IGMP Snooping function can be implemented on the following pages: Snooping Config,

Port Config, VLAN Config, Multicast VLAN, Querier Config, Profile Config, Profile Binding,

Packet Statistics and IGMP Authentication.

9.1.1 Snooping Config

To configure the IGMP Snooping on the switch, please firstly configure IGMP global

configuration and related parameters on this page.

If the multicast address of the received multicast data is not in the multicast address table, the

switch will broadcast the data in the VLAN. When Unknown Multicast Discard feature is enabled,

the switch drops the received unknown multicast so as to save the bandwidth and enhance the

process efficiency of the system. Please configure this feature appropriate to your needs.

Choose the menu Multicast →IGMP Snooping →Snooping Config to load the following page.

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