Configuring Global Dvmrp Settings - SMC Networks SMC6724L3 Management Manual

M R
ULTICAST OUTING
to build up a source-rooted multicast delivery tree that allows it to prevent
looping and determine the shortest path to the source of this multicast
traffic.
source
branch
leaf
leaf
When this router receives the multicast message, it checks its unicast
routing table to locate the port that provides the shortest path back to the
source. If that path passes through the same port on which the multicast
message was received, then this router records path information for the
concerned multicast group in its routing table and forwards the multicast
message on to adjacent routers, except for the port through which the
message arrived. This process eliminates potential loops from the tree and
ensures that the shortest path (in terms of hop count) is always used.

Configuring Global DVMRP Settings

DVMRP is used to route multicast traffic to nodes which have requested a
specific multicast service via IGMP. This router uses Reverse Path
Forwarding (RPF) to build a shortest-path delivery tree that begins at the
source and spreads out to reach group members through the network.
RPF uses three different techniques to dynamically reconfigure the
multicast spanning tree: broadcasting, pruning, and grafting.
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