ospf

OSPF (Open Shortest Path First)

True Link Sate open standard routing protocol, Known as shortest path first routing protocol,  works by using DIJKSTRA algorithm. OSPF uses bandwidth as a default metric to determine the best path to remote network. First a best path tree is constructed and then routing table is populated with resulting best path. It supports classless routing with unlimited hop count. It AS is 110, uses multicast address 224.0.0., it is not multi-routed protocol. It converges very quickly and loop free protocol. It can support load balancing up to 6 equal cast path and does not summarize route by default like EIGRP, IGRP and RIP, it use IP port number 89.

Area:- A logical set of network segments and their attached devices. Areas is 32-bit value usually are connected to other areas via routers, making up a single autonomous system, 50 routers can be in single area.