This attribute determines the metric usage for this RIP instance.
This flag is used to determine the way metrics are incremented.
RFC1058 way :
Sending Update: This is to use the metric for the route from the routing
table as the advertised metric to be sent for that route. Nothing is ever
added to this value from the sending side. The only special case
handling is that if the route being advertised is the network route of a
directly connectednetwork, the metric in the routing table will be zero.
Then the RipIf interface metric for the interface being advertised is used
as the advertise metric. If the interface being advertised is not a Rip
interface, then metric value of 1 is used.
Receiving Update: Add receiving interface's RIP metric to the metric for
the route in the received advertisement and install the result in the
receiver's routing table as the metric for that route.
Older way:
Sending Updates: Add the out going interfaces rip metric to the metric
for a route in the routing table to form the metric to be advertised for
that route.
Receiving Updates: The metric received in the advertisement for a route
is put directly in the routing table as the metric for that route.
Note: It is recommended that, all the routers in this autonomous system
should be following the rfc1058 metric system.
Setting this flag to disabled will have the effect of running the RIP with
old metric incrementing system.