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Interface
Cost
100 This value is used by the router in calculating the shortest path.
The default cost is calculated by using the bandwidth of the
interface. For this purpose, the bandwidth is taken as that of the
highest bandwidth port in the VLAN linked to the interface. The
interface cost is inversely proportional to this bandwidth. The
shortest path is that with the lowest cost, given by the highest
bandwidth
Transit
Delay
1 second The estimated number of seconds it takes to transmit a link state
update packet over this interface.
Range: 0-3600 seconds
Retransmit
Interval
5
seconds
The number of seconds between retransmitting link-state
advertisements to router adjacencies on this interface. This value
is also used when retransmitting database descriptions and
link-state request packets.
Range: 0-3600 seconds
Hello
Interval²
10
seconds
The interval, in seconds, between sending Hello packets out the
router interface. This interval determines how fast topology
changes will be detected. However, for small intervals, more
overhead will be incurred in exchanging routing information.
Range: 1-65535 seconds
Dead
Interval²
40
seconds
The number of seconds that a router’s Hello packets have not
been seen before its neighbors declare the router down. This
should be a multiple of the Hello interval.
Range: 1-65535 seconds
Poll
Interval
120
seconds
The interval, in seconds, between sending Hello packets to a
neighboring router from which Hello packets have not been
received for the Dead Interval period of time. The poll interval
must be much larger than the Hello Interval.
1. The Area ID is used to specify a group of contiguous networks and hosts. OSPF
protocol broadcast messages are restricted by area to limit their impact on network
performance.
2. This value must be the same for all routers attached to a common network.
Configuring DVMRP
Distance Vector Multicast Routing Protocol is used to route multicast traffic to nodes
which have requested a specific multicast service via IGMP. (See “DVMRP Routing
Protocol” on chapter 4.) To configure DVMRP, you must specify the routing metric,
probe interval, and neighbor router timeout.