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Cisco ME 3400 Ethernet Access Switch Software Configuration Guide
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Chapter 35 Configuring IP Unicast Routing Configuring RIP
Configuring RIP
The Routing Information Protocol (RIP) is an interior gateway protocol (IGP) created for use in small,
homogeneous networks. It is a distance-vector routing protocol that uses broadcast User Datagram
Protocol (UDP) data packets to exchange routing information. The protocol is documented in RFC 1058.
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; it is treated by RIP as a network to implement the default
routing feature. 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.
These sections contain this configuration information:
• Default RIP Configuration, page 35-19
• Configuring Basic RIP Parameters, page 35-20
• Configuring RIP Authentication, page 35-21
• Configuring Summary Addresses and Split Horizon, page 35-22

Default RIP Configuration

Table 35-4 shows the default RIP configuration.
Tab le 35-4 Default RIP Configuration
Feature Default Setting
Auto summary Enabled.
Default-information originate Disabled.
Default metric Built-in; automatic metric translations.
IP RIP authentication key-chain No authentication.
Authentication mode: clear text.
IP RIP receive version According to the version router configuration command.
IP RIP send version According to the version router configuration command.
IP RIP triggered According to the version router configuration command.
IP split horizon Varies with media.
Neighbor None defined.
Network None specified.