BGP - multicast routing

In situations where you want to run multicast services across multiple ASes, you can use MP-BGP to ensure that multicast routing information is propagated from AS to AS.

PIM is the protocol used inside an AS for routing of multicast traffic. It establishes multicast distribution trees and propagates multicast traffic along these trees within the AS.

MP-BGP, on the other hand, is an extension of BGP that supports multicast. It’s used to carry multicast routing information between different ASes.