The Distance Vector MulticastRouting Protocol (DVMRP) is a receiver-based routing protocol with a distance vector algorithm that determines the shortest path to the data source. It is a standard protocol for multicast backbones that determines the previous transmission segment back to the source in each case. Its basis is a reverse path flooding method. In this process, the router sends data packets at periodic intervals over all paths known to it in order to learn about the neighboring routers.
The determined connections are documented in extensive status tables. Since the routers and switches build a separate DVMRP tree for each group ID, the amount of information can become very extensive.
DVMRP is based on the Routing Information Protocol( RIP) and uses the Internet Group Management Protocol( IGMP) to exchange routing datagrams with neighboring routers. Multicast data units are forwarded using the RPM method, Reverse Path Multicasting. The specifications for the Distance Vector Multicast Routing Protocol date from 1988 and are described in RFC 1075.