OVERVIEW OF RIP

OVERVIEW OF RIP

RIP is an Interior Gateway Protocol (IGP) first used in computer routing in the ARPAnet as early as 1969. It is primarily intended for use in homogeneous networks of moderate size.

To determine the best path to a distant network, a router using RIP always selects the path that has the least number of hops. Each router that data must traverse is considered to be one hop.

ROUTING TABLE

The routing table in a router using RIP contains an entry for every known destination network. Each routing table entry contains the following information:

IP address of the destination network

Metric (hop count) to the destination network

IP address of the next router

Timer that tracks the amount of time since the entry was last updated

The router exchanges an update message with each neighbor every 30 seconds (default value), or if there is a change to the overall routed topology (also called triggered updates). If a router does not receive an update message from its neighbor within the route timeout period (180 seconds by default), the router assumes the connection between it and its neighbor is no longer available.

SPLIT HORIZON

Split horizon is a scheme for avoiding problems caused by including routes in updates sent to the router from which the route was learned. Split horizon omits routes learned from a neighbor in updates sent to that neighbor.

POISON REVERSE

Like split horizon, poison reverse is a scheme for eliminating the possibility of loops in the routed topology. In this case, a router advertises a route over the same port that supplied the route, but the route uses a hop count of 16, defining it as unreachable.

SUMMIT SWITCH INSTALLATION AND USER GUIDE

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Extreme Networks Summit1 manual Overview of RIP, Routing Table, Split Horizon, Poison Reverse