Routing Protocols with the help of Diagram

         Routers communicates with each other using Routing protocols. The protocols help routers to learn the network topology and changes that occur in the network topology . routing protocols use routing algorithms to decide the best output path for the received packet. Routing algorithm is a part of network layer software and should be correct, stable and simple. It should decide the perfect path for the packet depending on the network topology and traffic. For finding the best path, router considers number of hops, time delay and communication cost of the packet transmission.

   A large Internet is divided into groups of networks called as Autonomous System -AS . An AS consists of network groups and routers which are managed by  a single organization. Interior routing is used within AS, whereas, Exterior routing provides routing between two ASs.


Protocol Diagram :