Owner's Manual

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A multicast group is a group of end nodes that want to receive multicast packets from a multicast
application. After joining a multicast group, a host node must continue to periodically issue
reports to remain a member. Any multicast packets belonging to that multicast group are then
forwarded by the Switch from the port.
A Switch supporting IGMP Snooping can passively snoop on IGMP Query, Report, and Leave
packets transferred between IP Multicast switches and IP Multicast hosts to determine the IP
Multicast group membership. IGMP Snooping checks IGMP packets passing through the network
and configures multicasting accordingly. Based on the IGMP query and report messages, the
Switch forwards traffic only to the ports that request the multicast traffic. It enables the Switch
to forward packets of multicast groups to those ports that have validated host nodes. The Switch
can also limit flooding of traffic to IGMP designated ports. This improves network performance by
restricting the multicast packets only to switch ports where host nodes are located. IGMP
Snooping significantly reduces overall Multicast traffic passing through your Switch. Without
IGMP Snooping, Multicast traffic is treated in the same manner as a broadcast transmission,
which forwards packets to all ports on the network.
IGMPv1 Defined in RFC 1112. An explicit join message is sent to the Switch, but a
timeout is used to determine when hosts leave a group.
IGMPv2 Defined in RFC 2236. Adds an explicit leave message to the join message so
that
Switch can more easily determine when a group has no interested listeners on a
LAN.
IGMPv3 Defined in RFC 3376. Support for a single source of content for a multicast
group.
Global Settings
Click to enable or disable the IGMP Snooping feature for the Switch. Next, select whether you
wish to use V2 or V3. Finally, select whether you wish to enable or disable the Report Suppression
feature for the Switch.