IP multicast architecture
IP multicast addresses the following issues:
Where should the multicast source transmit information to? (Multicast addressing.)
What receivers exist on the network? (Host registration.)
Where is the multicast source that will provide data to the receivers? (Multicast source discovery.)
How is the information transmitted to the receivers? (Multicast routing.)
IP multicast is an end-to-end service. The multicast architecture involves the following parts:
Addressing mechanism—A multicast source sends information to a group of receivers through a multicast address.
Host registration—Receiver hosts can join and leave multicast groups dynamically. This mechanism is the basis for management of group memberships.
Multicast routing—A multicast distribution tree (a forwarding path tree for multicast data on the network) is constructed for delivering multicast data from a multicast source to receivers.
Multicast applications—A software system that supports multicast applications, such as video conferencing, must be installed on multicast sources and receiver hosts. The TCP/IP stack must support reception and transmission of multicast data.