Dell SmartFabric OS10 User Guide Release 10.5.4

Anycast RP using PIM

PIM Anycast RP provides load balancing and redundancy capabilities for Rendezvous Point (RP) routers in a multicast domain.

This feature allows you to configure two or more RPs with same IP address (RP address) in a multicast group. The shared RP address is advertised in Interior Gateway Protocol (IGP). The RP routers that share the same RP address form an Anycast RP set. Each router in the Anycast RP set is configured with two IP addresses: a shared RP address on the Loopback interface and a separate, unique IP address. The unique IP address is used for communication between the RPs. The Loopback address must be reachable to all PIM routers in the multicast domain. This configuration allows the RPs to share the load for source registration and to act as back-up routers for each other.

PIM enables multiple RPs to inform each other about active sources. When a source registers with an RP, that RP sends a PIM register message to all other members of the RP set informing that there is a new active source. Thus, each RP in the multicast domain knows about the active sources of the other RPs.

IGP protocols such as OSPF routes the sources and receivers to the RPs with the best route. Packets sent to the RP address are delivered to the nearest RP with this address. When an RP with the best route fails, IGP automatically recalculates the best route and takes the sources and receivers to the closest operating RP. This failover mechanism ensures that connectivity is maintained, and traffic disruption is minimal.