User’s Manual of WGSD-1022/WGSD-8000

on the network.

The Time-to-Live (TTL) field of query messages is set to 1 so that the queries will not be forwarded to other sub networks.

IGMP version 2 introduces some enhancements such as a method to elect a multicast queried for each LAN, an explicit leave message, and query messages that are specific to a given group.

The states a computer will go through to join or to leave a multicast group are shown below:

Non-Member

Leave Group

Leave Group

(Stop Timer)

Join Group

 

(Send Report,

 

Start Timer)

 

Query Received

 

Delaying Member

(Start Timer)

Idle Member

Report Received

 

 

 

(Stop Timer)

 

 

Timer Expried

 

 

(Send report)

 

IGMP State Transitions

IGMP Snooping Configuration

The default status of the IGMP Snooping function is disabled. To turn on the IGMP Snooping, select “Enable” of the IGMP Snooping Status field and click on the “OK” button to save.

4.3.3.1 IGMP Configuration

The switch support IP multicast, you can enable IGMP protocol on web management's switch setting advanced page, then display the IGMP snooping information in this page, you can view difference multicast group VID and member port in here, IP multicast addresses range from 224.0.0.0 through 239.255.255.255.

The Internet Group Management Protocol (IGMP) is an internal protocol of the Internet Protocol (IP) suite. IP manages multicast traffic by using switches, routers, and hosts that support IGMP. Enabling IGMP allows the ports to detect IGMP queries and report packets and manage IP multicast traffic through the switch. IGMP have three fundamental types of message as follows:

Message

Description

 

 

A message sent from the querier (IGMP router or switch) asking for a response

Query

from each host belonging to the multicast group.

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