Distance Vector routing
Maintain a “vector” of distances to each possible destination at each router. (Bunch of signposts)
How to find distances ?
- Distance to local network is 0.
- Look in neighbors’ distance vectors, and add link cost to reach the neighbor
- Find which direction yields minimum distance to to particular destination. Turn signpost (I.e. next hop, and cost) that way.
- Keep checking if neighbors change their signposts (vectors) and modify local vector (signposts) if necessary.
- Simple to code. Naturally a distributed algorithm. Based on “Bellman-Ford” algorithm.