PIM Sparse-Mode (SM) Notes – RFC 4601

Uses both Shared-Tree (*,G) and Source-Tree (S,G). PIM Sparse-Mode (SM) steps: Discover PIM neighbor and elect DR. PIM is the infrastructure to deliver the multicast packet. It builds the multicast network hop-by-hop. It takes the advantage of the routing table to perform RPF but it does not really matter what routing protocol derives it from….