Which interior gateway routing protocol is based on the shortest path first or link-state algorithm?

The correct answer, Open Shortest Path First (OSPF), is indeed based on the shortest path first (SPF) or link-state algorithm. OSPF functions by creating a complete map of the entire network topology, allowing routers to use Dijkstra’s algorithm to determine the most efficient route for data packets.

This link-state approach means that OSPF routers share information about the state of their links with all other routers within the same area, enabling them to maintain a consistent view of the network. This leads to quicker convergence times and more robust routing decisions compared to distance-vector protocols.

In contrast, the other options represent different types of routing mechanisms. Routing Information Protocol (RIP) employs a distance-vector algorithm, which computes routes based on the number of hops rather than evaluating the actual path characteristics. Enhanced Interior Gateway Routing Protocol (EIGRP), while it utilizes aspects of both distance-vector and link-state, does not strictly adhere to the link-state model. Border Gateway Protocol (BGP) is an exterior gateway protocol used primarily for routing between different autonomous systems, and it operates on a completely different basis than interior gateway routing protocols like OSPF.

Thus, OSPF is the only choice that accurately fits the criteria of using