Explain why IGMP is needed in a network?
The IGMP or Internet Group Management Protocol is an internet protocol that gives a way for a computer connected to the internet to report or state its multicast group membership to nearby routers. In multicasting, a computer connected to the internet is allowed to send or transmit content to numerous computers that have identified themselves as interested in accepting the content from the originating computer.
The IGMP or Internet Group Management Protocol is part of the network layer which is used in the OSI or Open Systems Interconnection communication model. It is officially described in the IETF or Internet Engineering Task Force RFC or Request for Comments 2236. IGMP snooping is the process or method of listening to IGMP network traffic.
This feature lets a network switch to listen in or eavesdrop on the IGMP conversation between routers and hosts.