
2.4 Multicast Routing Fundamentals 125
2.4.3 Protocol Independent Multicast
Protocol Independent Multicast, PIM, is a major multicast routing protocol for IPv4, and is the
only protocol for IPv6 available in the real world. PIM basically requires that all routers in a
routing domain support the protocol, and, unlike DVMRP (Distance Vector Multicast Routing
Protocol [RFC1075]), PIM does not require tunneling for bypassing routers that do not support
the protocol.
PIM version 2, the current version of PIM, supports multiple network protocols: the packet
format and the specification support both IPv4 and IPv6 (and even other or future network
protocols). ...