What is the priority of the routing table in relation to the RPF?

The priority of the routing table in relation to the Reverse Path Forwarding (RPF) is indeed to prioritize the shortest distance route. RPF is a technique used in multicast routing to ensure that multicast traffic is forwarded only on interfaces that lead back to the source of that traffic. To do this effectively, the routing table is consulted to determine which available routes are the shortest and thus most efficient.

When the RPF checks incoming packets, it uses the information from the routing table to construct the path back to the source and compare it against the interface on which the multicast packet was received. If the interface aligns with the shortest path defined in the routing table, then RPF validates the incoming packet as legitimate. This method helps prevent routing loops and ensures that multicast traffic is being delivered optimally.

The accuracy of the multicast routing relies heavily on the routing table reflecting the best routes, which are typically those with the shortest metrics or distances. Hence, the emphasis on the shortest distance route being prioritized validates the operation of the RPF in proper network functioning.