D-Link DGS-3308TG User Manual page 106

Interface Name:[
field. This must be a previously defined IP interface. See Setting up IP Interfaces in Chapter 6 of this manual
for more information.
Note: The Distance Vector Multicast Routing Protocol (DVMRP) is a hop-based method of building
multicast delivery trees from multicast sources to all nodes of a network. Because the delivery
trees are 'pruned' and 'shortest path', DVMRP is relatively efficient. Because multicast group
membership information is forwarded by a distance-vector algorithm, propagation is slow.
DVMRP is optimized for high delay (high latency) relatively low bandwidth networks, and can
be considered as a 'best-effort' multicasting protocol. See Chapter 5, Distance-Vector Multicasting
Routing Protocol for more information.
Note: DVMRP resembles the Routing Information Protocol (RIP), but is extended for multicast
delivery. It relies upon RIP hop counts to calculate 'shortest paths' back to the source of a
multicast message, but defines a 'route cost' to calculate which branches of a multicast delivery
tree should be 'pruned' – once the delivery tree is established.
Note: When a sender initiates a multicast, DVMRP initially assumes that all users on the network will
want to receive the multicast message. When an adjacent router receives the message, it checks
its unicast routing table to determine the interface that gives the shortest path (lowest cost) back
to the source. If the multicast was received over the shortest path, then the adjacent router
enters the information into its tables and forwards the message. If the message is not received
on the shortest path back to the source, the message is dropped.
Note: DVMRP version 3 incorporates the Reverse Path Multicasting algorithm. See Chapter 5, Reverse
Path Multicasting, for more information.
Neighbor Time-Out Interval:[35
the time period for which DVMRP will hold Neighbor Router reports before issuing poison route messages. The
default is 35 seconds.
Figure 6-44. DVMRP Interface Configuration screen
] – Enter the name of the IP interface for which DVMRP is to be configured in this
] – This field allows an entry between 1 and 65,535 seconds and defines
8-port Gigabit Ethernet Switch User's Guide
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