Which choice below is the earliest and the most commonly found
Interior Gateway Protocol?

A.
OSPF

B.
RIP

C.
IGRP

D.
EAP

Explanation:
The Routing Information Protocol (RIP) bases its routing path on
the distance (number of hops) to the destination. RIP maintains optimum
routing paths by sending out routing update messages if the
network topology changes. For example, if a router finds that a particular
link is faulty, it will update its routing table, then send a copy of
the modified table to each of its neighbors.
* the Open Shortest Path First (OSPF) is a link-state hierarchical routing algorithm
intended as a successor to RIP. It features least-cost routing, multipath
routing, and load balancing.
* the Internet Gateway Routing Protocol (IGRP) is a Cisco protocol that uses a composite metric
as its routing metric, including bandwidth, delay, reliability, loading, and maximum transmission
unit.
* the Extensible Authentication Protocol (EAP), is a general protocol for PPP authentication that
supports multiple remote authentication mechanisms. Source: Introduction to Cisco Router
Configuration edited by Laura Chappell (Cisco
Press, 1999).