Which routing protocol needs to maintain a consistent view of the network topology?

The routing protocol that needs to maintain a consistent view of the network topology is OSPF (Open Shortest Path First). OSPF is a link-state routing protocol that requires each router in the OSPF area to have a complete and identical view of the network topology to make accurate routing decisions. This is accomplished through the use of Link State Advertisements (LSAs), which allow routers to share information about their directly connected links and their states.

Each OSPF router independently computes the shortest path to each destination using the Dijkstra algorithm, based on the complete topology map it has constructed from the LSAs. This ensures that all routers have a synchronized understanding of the network’s structure, contributing to efficient routing and fault tolerance.

In contrast, other protocols like EIGRP are distance vector protocols that do not require a full view of the topology but rather use metrics to determine the best paths. While RIP also relies on distance-vector principles, BGP, being a path vector protocol, focuses more on policy-based routing rather than maintaining a detailed view of topology changes. Therefore, OSPF is specifically designed to require a consistent view of the entire network to function effectively.