ABSTRACT
Routing is the procedure of finding a path from a sender to every receiver or destination in the network. Routing algorithms calculate these paths. There are several routing protocols, ranging from simple telephone network routing protocols to complex Internet routing protocols. The terms
routing
and
forwarding
are usually used interchangeably in the networksrelated literature, but these two terms are quite different in their operations. Routers deploy both of these processes. Routing is responsible for determining the end-to-end paths that packets will take from sender to destination. Routing is implemented by routing algorithms, which are responsible for filling in and updating the routing tables. A routing table contains at least two columns: the first is the address of a destination network, and the second the address of the network node that is the next hop to this destination. When a packet arrives at a router, the router controller looks up the routing table to decide the next hop for the packet. Forwarding is concerned with the localized action of a router for transferring a datagram from an input link interface to the appropriate output link interface.
