3Com WX3000 operation manual RIP Configuration, RIP Overview, Basic Concepts, RIP routing database

3 RIP Configuration

When configuring RIP, go to these sections for information you are interested in:

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RIP Overview

RIP Configuration Task List

RIP Configuration Example

Troubleshooting RIP Configuration

The term router in this chapter refers to a router in a generic sense or a WX3000 series device running a routing protocol.

RIP Overview

Routing information protocol (RIP) is a simple interior gateway protocol (IGP) suitable for small-sized networks. RIP is not recommended in complicated large networks.

Basic Concepts

RIP

RIP is a distance-vector (D-V) algorithm–based protocol. It uses port 520 to exchange routing information through UDP packets.

RIP uses hop count (also called routing cost) to measure the distance to a destination address. In RIP, the hop count from a router to its directly connected network is 0, and that to a network which can be reached through another router is 1, and so on. To restrict the time to converge, RIP prescribes that the cost is an integer ranging from 0 and 15. The hop count equal to or exceeding 16 is defined as infinite; that is, the destination network or host is unreachable. This limitation makes RIP not suitable for large networks.

To improve performance and avoid routing loop, RIP supports split horizon. Besides, RIP can import routes discovered by other routing protocols.

RIP routing database

Each RIP router has a routing table containing routing entries of all reachable destinations, and each routing entry contains:

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Destination address: IP address of a host or network.

Next hop: IP address of an interface on the adjacent router that IP packets should pass through to reach the destination.

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