How Protocol Independent Muliticast - Sparse Mode (PIM-SM) works

RFC-2902 encouraged the evaluation and written reports on these multicast protocols, and mechanisms for different types of protocols. I did my master thesis at the University of Colorado, Boulder and concluded that PIM-SM was the best solution at the time for inter domain multicast routing protocols. The following is a summary on how PIM-SM works.

The most important part of the Inter Domain Multicast Routing protocol is captured here.