KYLAND Technology SICOM3024P, Web Operation Manual

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Advanced Configuration
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the port that receives the IGMP report to the member port list. If a router port exists, it is
also added to the member port list. Then the switch forwards the IGMP report to other
devices through the router port, so that the other devices establish the same multicast
entry.
6.8.3 Principle
IGMP Snooping manages and maintains multicast group members by exchanging related
packets among IGMP-enabled devices. The related packets are as follows:

General query packet: The querier periodically sends general query packets (destination
IP address: 224.0.0.1) to confirm whether or not the multicast group has member ports.
After receiving the query packet, a non-querier device forwards the packet to all its
connected ports.

Specific query packet: If a device wants to leave a multicast group, it sends an IGMP
leave packet. After receiving the leave packet, the querier sends a specific query packet
(destination IP address: IP address of the multicast group) to confirm whether the group
contains other member ports.

Membership report packet: If a device wants to receive the data of a multicast group, the
device sends an IGMP report packet (destination IP address: IP address of the multicast
group) immediately to respond to the IGMP query packet of the group.

Leave packet: If a device wants to leave a multicast group, the device will send an IGMP
leave packet (destination IP address: 224.0.0.2).
6.8.4 Web Configuration
1. Enable IGMP Snooping, as shown in the following figure.