Asante Technologies 35516 user manual Configuring RIP, Enable RIP, Allow Unicast Updates for RIP

5.4 Configuring RIP

The Routing Information Protocol (RIP) is a commonly used interior gateway protocol (IGP) created for use in small, homogeneous networks. It is a distance-vector routing protocol, documented in RFC 1058.

RIP uses broadcast User Datagram Protocol (UDP) data packets to exchange routing information. The IC35516 sends, or advertises, routing information updates every 30 seconds. If a router does not receive an update from another router for 180 seconds or more, it will mark the routes served by the non-updating router as being unusable. If there is still no update after another 120 seconds, the router will remove all routing table entries for the non-updating router.

RIP uses the metric hop count 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 metric of zero; an unreachable network has a metric of 16. This makes RIP an unsuitable routing protocol for large networks with many routers.

A router that is running RIP can receive a default network via an update from another router that is running RIP, or the router can source the default network itself with RIP. In both cases, the default network is advertised to other RIP neighbors. RIP sends updates to the interfaces in the specified networks. If an interface's network is not specified, it will not be advertised in any RIP update. The IC35516 supports RIP Version 2.

5.4.1 Enable RIP

RIP must be enabled before carrying out any other of the RIP commands. To enter router configuration mode for RIP, start in global configuration mode and enter the following command(s):

Router(config)#

Router(config)# router rip

Router(config-rip-router)#

The network command enables RIP interfaces between certain numbers of a special network address. For example, if the network for 10.0.0.0/24 is RIP enabled, this would result in all the addresses from 10.0.0.0 to 10.0.0.255 being enabled for RIP.

Command	Purpose
router rip	Enable a RIP routing process, which places you in router
	configuration mode.
network {IP prefix}	Associate a network with a RIP routing process.

5.4.2 Allow Unicast Updates for RIP

Because RIP is normally a broadcast protocol, in order for RIP routing updates to reach non-broadcast networks, it is necessary to establish a direct link between routers. Use the following command in router configuration mode.

Command	Purpose
neighbor ip-address	Define a neighboring router with which to exchange routing
	information.

To control the set of interfaces with which you want to exchange routing updates, you can disable the sending of routing updates on specified interfaces by configuring the passive-interfacecommand.

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