Multicast-enabled end hosts use the Internet Group Management Protocol (IGMP) to communicate group membership information to nearby multicast routers, facilitating the efficient delivery of multicast traffic.
The protocol that multicast-enabled end hosts use to communicate group membership information is IGMP, which stands for Internet Group Management Protocol. It is a communications protocol used by hosts and adjacent routers on IPv4 networks to establish multicast group memberships.
IGMP is used for one-to-many networking applications such as online streaming video and gaming, and allows more efficient use of resources when supporting these types of applications. IGMP operates between the client computer and a local multicast router. Devices in the network can then use this group membership information to direct multicast traffic to the appropriate receivers without broadcasting to devices that do not wish to receive the multicast traffic.