Distance vector algorithms (also known as Bellman-Ford algorithms) call for each router to send all or some portion of its routing table only to its neighbors. Distance vector algorithms perform routing decisions based upon information provided by neighboring routers.

Distance vector protocols use fewer system resources but can suffer from slow convergence and may use metrics that do not scale well to larger systems. Distance vector protocols are based on finding the distance (number of hops) and vector (direction) to any link on the internetwork. The algorithms involve passing copies of a complete routing table from router to router on a periodic basis.

This type of routing protocol requires that each router simply inform its neighbors of its routing table. For each network path, the receiving routers pick the neighbor advertising the lowest cost and then adds this entry into their routing table for readvertisement. RIP and IGRP are common distance vector routing protocols.

Web Links Distance Vector Routing http://www.cs.uwa.edu.au/~chris/ cnet/aricstewart/