The Control Plane: Distance Vector - Routing Information Protocol

Introduction

The Routing Information Protocol (RIP) based on the famous Belmman-Ford algorithm belongs to the distance vector class of routing algorithms and was used in ARPANET. While it used to be incredibly popular, it’s not used very much now. There are other distance vector routing algorithms too such as Ford-Fulkerson.

Initial State

Each router or ‘node,’ maintains a routing table that initially contains the estimated cost to each of its neighbors.

Consider the following example of a small network where the yellow circles represent nodes, the black lines represent links, and the purple numbers represent the cost of each link.