Which protocol uses the concept of successor and feasible successor routes?

The protocol that utilizes the concept of successor and feasible successor routes is EIGRP (Enhanced Interior Gateway Routing Protocol). EIGRP employs these concepts as part of its route selection process in order to maintain efficient and reliable routes within a network.

A successor route in EIGRP is the primary route to a destination, which is used for data forwarding. It is the best route based on metrics such as bandwidth, delay, load, and reliability. A feasible successor, on the other hand, is a backup route that can be used if the successor route fails. For a route to be considered a feasible successor, it must meet certain criteria, primarily that its advertised distance must be less than the feasible distance of the successor.

This dual-route approach allows EIGRP to provide fast convergence and ensures redundancy, helping to minimize downtime if a primary route becomes unavailable. The ability to rapidly switch between the successor and feasible successor routes enhances network resilience and performance.

In comparison, OSPF (Open Shortest Path First) focuses on link-state updates and path determination based on cost metrics, while RIP (Routing Information Protocol) relies on hop count as its sole metric and does not use the concepts of successor and feasible successor. IS-IS (Intermediate System to Intermediate