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User Manual
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IGMP Proxy
IP hosts use Internet group management protocol (IGMP) to report their multicast group
memberships to neighboring routers. Similarly, multicast routers use IGMP to discover
which of their hosts belong to multicast groups. Your router supports IGMP proxy that
handles IGMP messages. When enabled, your router acts as a proxy for a LAN host
making requests to join and leave multicast groups, or a multicast router sending
multicast packets to multicast groups on the WAN side.
IGMP Proxy
IGMP ProxyIGMP Proxy
IGMP Proxy
Multicasting is a form of limited broadcast. UDP is used to send datagrams to all hosts
that belong to what is called a Host Group. A host group is a set of one or more hosts
identified by a single IP destination address. The following statements apply to host
groups:

Anyone can join or leave a host group at will.
 There are no restrictions on a host’s location.

There are no restrictions on the number of members that may belong to a host
group.

A host may belong to multiple host groups.