DVMRP is the original IP Multicast routing protocol. It was designed to run over both multicast capable lans (like Ethernet) as well as through non-multicast capable routers. In this case, the IP Multicast packets are "tunneled" through the routers as unicast packets. This replicates the packets and has an effect on performance, but has provided an intermediate solution for IP Multicast routing on the Internet while router vendors decide to support native IP Multicast routing.
An earlier version of DVMRP was documented as RFC 1075 but it is not representative of the protocol in use today. The GATED version of DVMRP is compatible with the XEROX PARC releases 2.x and 3.x. It will perform pruning and grafting if the upstream neighbor supports it. It understands the capability flags introduced in XEROX PARC Release 3.5.
This is a preliminary release of DVMRP.
dvmrp yes | no | on | off [ { interface interface_list dvrmp_parameters [enable | disable] [metric metric] [threshold threshold] [ratelimit rate] [advertise network [(mask mask) | (masklen number)] [metric metric]] ; tunnel host lcladdr local_address [enable | disable] [metric metric] [threshold threshold] [ratelimit rate] ; traceoptions trace_options ; } ] ;
The dvmrp statement enables or disables the DVMRP protocol. If the dvmrp statement is not specified, the default is dvmrp off; If enabled, DVMRP will default to enabling all interfaces that are multicast capable. These interfaces are identified by the IFF_MULTICAST interface flag.
Note: only one multicast routing protocol can be configured on a port at a time.
The options are as follows:
Packet tracing options (which may be modified with detail, send or recv):
See the sample multicast router configurations.
Last updated April 26, 1997.
Gated@gated.merit.edu