2. Multicast addressing

2.1 Multicast group concept

IP multicast is based on the notion of a group. A multicast group identifies a set of receivers who are interested in receiving a particular data stream. This group has no limit:

• physical or geographical: multicast terminals can be located on any Internet network;

• numeric: the size of a multicast group can vary from a single terminal to all the terminals in the IP multicast network.

Terminals interested in receiving traffic must join the group using IGMP (Internet Group Management Protocol ) for IPv4 terminals, or MLD (Multicast Listener Discovery ) for IPv6 terminals. A terminal must be a member of a group to receive a given multicast stream....