IP multicast is a method of sending Internet Protocol (IP) datagrams to a group of interested receivers in a single transmission. It is often employed for streaming media applications on the Internet and private networks. The method is the IP-specific version of the general concept of multicast networking. It uses specially reserved multicast address blocks in IPv4 and IPv6. In IPv6, IP multicast addressing replaces broadcast addressing as implemented in IPv4.
IP multicast is described in RFC 1112. IP multicast was first standardized in 1986. Its specifications have been augmented in RFC 4604 to include group management and in RFC 5771 to include administratively scoped addresses.
Read more about IP Multicast: Technical Description, Addressing, Protocols and Applications, Routing, Layer 2 Delivery, Reliable Multicast, Wireless (802.11) Considerations, Implementations, History and Milestones, Commercial Deployment, IP Multicast Software