What role does Auto-RP serve in a PIM network?

Auto-RP is used in Protocol Independent Multicast sparse-mode environments to distribute rendezvous point information automatically. In PIM sparse mode, multicast routers must know which RP is responsible for specific multicast group ranges. Without a dynamic RP-discovery mechanism, administrators would have to configure RP information manually across routers. Auto-RP solves that by allowing candidate RPs to announce themselves and mapping agents to advertise group-to-RP mappings throughout the multicast domain. Therefore, option B is correct. Option A is incorrect because Auto-RP does not distribute IGMP traffic; IGMP operates between hosts and local multicast routers to manage group membership. Option C is wrong because Auto-RP does not automate leaf-router configuration generally; it specifically distributes RP mapping information. Option D is also inaccurate because Auto-RP does not perform an election in the same way as BSR. It advertises candidate RP and mapping-agent information so routers can learn RP mappings. The key ENCOR concept is multicast control-plane discovery for PIM sparse-mode RP selection. References/topics: ENCOR multicast, PIM sparse mode, Auto-RP, rendezvous point discovery, multicast group-to-RP mapping.