quote of the day, doyle, dv versus path vector...

from ospf and is-is, jeff doyle


All of the vector protocols with the exception of BGP are commonly called distance vector protocols. BGP is called a path vector protocol, because it tracks not paths through routers but paths through autonomous systems. Is there really any difference between distance vector and path vector? At least one acquaintance likes to differentiate them by saying that a distance vector route is a sum of quantities, whereas path vector is a sequence of quantities. My own opinion is that it is all semantics. Although BGP has a different application than an IGP, and does indeed describe its routes as a series of AS numbers, it is still a distance vector protocol.