UNICOM Electric SmartGST-2402M - Manual (Page 60)

UNICOM SmartGST-2402M
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5-4-6-1. IGMP Snooping
The SmartGST-2401 supports IP multicast. Users can enable IGMP protocol on the
Web Management’s Advanced page. It displays the IGMP snooping information where
you can view the difference between the multicast group VID and the member port. The
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, report packets, and manage IP
multicast traffic through the switch. IGMP has three fundamental types of message:
Message Description
Query
A message sent from the querier (IGMP router or switch) asking for a
response from each host belonging to the multicast group.
Report
A message sent by a host to the querier to indicate that the host wants
to be or is a member of a given group indicated in the report message.
Leave
Group
A message sent by a host to the querier to indicate that the host has
ceased to be a member of a specific multicast group.
5-4-6-2. Static MAC Address
When you add a static MAC address, it remains in the switch's address table,
regardless of whether the device is physically connected to the switch or not. This saves
the switch from having to re-learn a device's MAC address when it is disconnected or
the powered-off device is active on the network again.