Internet Group Management Protocol Version 1 (IGMPv1)

Internet Group Management Protocol Version 1 (IGMPv1)
As the name indicates,
Internet Group Management Protocol version 1 (IGMPv1)
was the first
version of the protocol. It was a result of RFC 1112. The purpose of this protocol is to enable
hosts to subscribe to or join specified multicast groups. By subscribing to groups, the hosts are
thereby enabled to receive multicast data forwarded from the router.
IGMP has several processes that it executes to manage multicast group subscription
and maintenance. We will discuss them in greater detail so you can get an understanding of
what happens.
Three processes are employed by version 1 of IGMP:

Query

Join

Leave
Managing Multicast in an Internetwork
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These processes are the means by which multicast group membership is maintained. The first
two processes are functional processes, whereas the Leave process is more of a timeout than a
formal request. Each process is defined in detail next.