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IGMP (Internet Group Multicast Protocol) is a network-layer protocol used to establish
membership in a Multicast group - it is not used to carry user data. IGMP version 2 (RFC 2236)
is an improvement over version 1 (RFC 1112) but IGMP version 1 is still in wide use. If you
would like to read more detailed information about interoperability between IGMP version 2
and version 1, please see sections 4 and 5 of RFC 2236. The class D IP address is used to
identify host groups and can be in the range 224.0.0.0 to 239.255.255.255. The address
224.0.0.0 is not assigned to any group and is used by IP multicast computers. The address
224.0.0.1 is used for query messages and is assigned to the permanent group of all IP hosts
(including gateways). All hosts must join the 224.0.0.1 group in order to participate in IGMP.
The address 224.0.0.2 is assigned to the multicast routers group.
The BIPAC-5100/5100W supports both IGMP version 1 (IGMP-v1) and IGMP version 2
(IGMP-v2). At start up, the BIPAC-5100/5100W queries all directly connected networks to
gather group membership. After that, the BIPAC-5100/5100W periodically updates this
information. IP multicasting can be enabled/disabled on the BIPAC-5100/5100W LAN and/or
WAN interfaces in the web configurator (LAN; WAN). Select None to disable IP multicasting on
these interfaces.
4.5 Configuring LAN
Click LAN to open the following screen.
The following table describes the labels in this screen.