In EIGRP, what is defined as an alternate route to the destination that meets the feasibility condition?

In EIGRP (Enhanced Interior Gateway Routing Protocol), a feasible successor is defined as an alternate route to the destination that meets the feasibility condition. This means that the feasible successor is a backup route that can be used if the primary route (successor) fails.

The feasibility condition requires that the reported distance of the alternate route must be less than the feasible distance of the current successor route. This helps in ensuring that the alternate path can be considered valid and reliable for routing decisions. The feasible successor is important for loop-free operation in EIGRP, as it allows for rapid convergence when there is a failure in the primary route.

The other terms mentioned, such as successor, feasible distance, and advertised distance, play different roles in the EIGRP routing process. The successor is the primary next-hop route to the destination. Feasible distance refers to the metric of the best currently known route to that destination. Advertised distance is the metric that a neighbor router reports for a route to a specific destination. While these terms are related and critical for EIGRP's function, they do not define an alternate route that meets the feasibility condition, which is specifically described by the term feasible successor.