Apart from adding support for IPv6 addresses, PIMv6 adds the following functionality to existing PIM implementation:
The Address List Option, in a Hello message, advertises all the secondary addresses associated with the source interface of the router originating the message. These addresses are associated with the neighbor, and are used to compute the neighbor‘s primary address. The function NBR uses information gathered through PIM Hello messages to map the IP address A of a directly connected PIM neighbor on interface I to the primary IP address of the same router. The primary IP address of a neighbor is the address that it uses as the source of its PIM Hello messages.
Two PIMv6 domains can be connected through an IPv4 network. In this case, PIMv6 routers across the domains communicate over the IPv4 network by tunneling the IPv6 packets inside IPv4 headers. To enable such communication, PIMv6 provides support for Tunnel interfaces.
The following tunnel types are supported: