About multicast routing and forwarding

Each multicast routing protocol has its own routing table. Multicast routing information in routing entries generated by the multicast routing protocols and statically configured multicast routing entries are summarized in a set of (S, G) and (*, G) entries. All the (S, G) and (*, G) entries form a general multicast routing table. The optimal multicast routing entries in the general multicast routing table are added to the multicast forwarding table to guide multicast data forwarding.