efficiently determine the best route from one point to all points. Several protocols are available
to determine the best path for multicast routing. Distance Vector Multicast Routing Protocol
(DVMRP) was the first multicast routing protocol to be widely accepted. As the name implies,
DVMRP is a distance vector protocol. It has many similarities to RIP. DVMRP served the
networking community well as a first-generation multicast routing protocol. Its periodic
updates and hop count limitations disqualify it as the preferred protocol for today's
internetworks. DVMRP should be employed in new designs only when backward compatibility
to an existing infrastructure is a design concern.
enabled on a Cisco router. PIM allows any unicast routing protocol to support IP multicast. PIM
can be integrated into existing networks that are running IGRP, EIGRP, RIP, and OSPF.
Multicast Open Shortest Path First (MOSPF) allows multicast traffic to be forwarded within an
OSPF v2 unicast network.