Routing is a process of selecting a path for traffic across one or more networks. Network routing protocols use metrics to determine the optimal path for data packet delivery. For example, in the case of packet-switching networks such as the internet, routing helps to determine the best paths for Internet Protocol (IP) packets to travel from source to their destination.
Routing is performed by layer 3 or network layer for the process of most efficient path determination.
It can be classified into three categories :
* Static routing
* Dynamic routing
* Default routing
