Cisco IE 4000, Software Configuration Manual

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Configuring IP Unicast Routing
Configuring RIP
Switch(config-router)#
end
Configuring RIP
The Routing Information Protocol (RIP) is an interior gateway protocol (IGP) used in small, homogeneous networks. It is
a distance-vector routing protocol that uses broadcast User Datagram Protocol (UDP) data packets to exchange routing
information. You can find detailed information about RIP in
IP Routing Fundamentals, published by Cisco Press.
Using RIP, the switch sends routing information updates (advertisements) every 30 seconds. If a router does not receive
an update from another router for 180 seconds or more, it marks the routes served by that router as unusable. If there is
still no update after 240 seconds, the router removes all routing table entries for the non-updating router.
RIP uses hop counts to rate the value of different routes. The hop count is the number of routers that can be traversed
in a route. A directly connected network has a hop count of zero; a network with a hop count of 16 is unreachable. This
small range (0 to 15) makes RIP unsuitable for large networks.
If the router has a default network path, RIP advertises a route that links the router to the pseudonetwork 0.0.0.0. The
0.0.0.0 network does not exist, but is treated by RIP as a network to implement default routing. The switch advertises
the default network if a default was learned by RIP or if the router has a gateway of last resort and RIP is configured with
a default metric. RIP sends updates to the interfaces in specified networks. If an interface’s network is not specified, it
is not advertised in any RIP update.
This section includes the following topics:

Default RIP Configuration, page 818

Configuring Basic RIP Parameters, page 818

Configuring RIP Authentication, page 820

Configuring Split Horizon, page 821