PIM Group-to-Rendezvous-Point Mapping

Each PIM-SM router in a Protocol Independent Multicast (PIM) Domain which supports Any Source Multicast (ASM) maintains Group-to-RP mappings which are used to identify a Rendezvous Point(RP) for a specific multicast group. PIM-SM has defined an algorithm to choose a RP from the Group-to-RP mappings learned using various mechanisms. This algorithm does not consider the PIM mode and the mechanism through which a Group-to-RP mapping was learned. This document defines a standard algorithm to deterministically choose between several Group-to-RP mappings for a specific group. This document first explains the requirements to extend the Group-to-RP mapping algorithm and then proposes the new algorithm.