IGMP Snooping
IGMP Snooping is the process of listening to IGMP network traffic. IGMP Snooping, as implied by
the name, is a feature that allows a layer 2 switch to “listen in” on the IGMP conversation between
hosts and routers by processing the layer3 IGMP packets sent in a multicast network.
When IGMP Snooping is enabled in a switch it analyzes all IGMP packets between hosts
connected to the switch and multicast routers in the network. When a switch hears an IGMP report
from a host for a given multicast group, the switch adds the host’s port number to the multicast list
for that group. And, when the switch hears an IGMP Leave, it removes the host’s port from the table
entry.
It prevents flooding of IP multicast traffic, and limits bandwidth intensive video traffic to only the
subscribers.
IGMP Configuration
➤
IGMP Enabled: When enabled, the switch monitors network traffic to determine which hosts
want to receive multicast traffic.
➤
Router Ports: Set if ports are connecting to the IGMP administrative routers.
➤
Unregistered IPMC Flooding enabled: Set the forwarding mode for unregistered (not-joined) IP
multicast traffic. The traffic floods when enabled, and forward to router-ports when disabled.
Wildix WSG08POE User Manual
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