an interface
OSPF is a link-state routing protocol.
There are actually two OSPF and IS-IS
OSPF is a link-state routing protocol that helps Routers exchange IP routes. OSPF Adjacencies is the established "neighborship" between two OSPF routers in order to make the exchange of routes. In this case, Adjacency means the same as "peering", that the OSPF speakers (routers) are able to "talk" to each other.
The "ip ospf cost" command can be used to manually set the cost of an OSPF-enabled interface. The "bandwidth" command can indirectly affect OSPF metric calculation by adjusting the bandwidth on an interface, which in turn affects the OSPF metric calculation.
link state advertisement
OSPF is a classless link-state routing protocol. RIP version 1 and IGRP are both classful distance vector routing protocols, EIGRP is a hybrid protocol that supports classless addressing.
the extensive flooding of LSAs throughout the OSPF areathe excessive adjacencies when the number of routers increases
OSPF
RIP is an Interior Gateway Protocol and the most widely accepted routing protocol. It is also known by the name of the Unix daemon program routed. RIP is straightforward: it arranges to have routers to broadcast their entire current routing database periodically OSPF is a link-state algorithm. OSPF specifies a class of messages called link-state advertisements (LSAs) that allow routers to update each other about the LAN and WAN links to which they are connected. When a change is made to the network, LSAs flow between routers. OSPF routers receive link-state updates and store them in a topology database in memory. OSPF networks as an end-station-to-router protocol. OSPF addresses all the deficiencies of RIP, without affecting connectivity to RIP based networks.
OSPF LSA throttling helps the dampening of LSA updates in OSPF during times of network instability.
OSPF is short form of open shortest path first. OSPF is based on linked state routing.
OSPF uses the path cost metric to determine the best route to a destination network. The path cost is based on the bandwidth of the link. Lower path costs indicate faster or more desirable paths.