CISCO CCNA 200-301 Q184

Which of the following values will be used by a router to make a routing decision when two routes have been learned from OSPF?

A. cost
B. administrative distance
C. composite metric
D. hop count

Correct Answer: A

Explanation:
When two routes have been learned by OSPF to same network, the best route will be chosen based on lowest cost. Cost is the metric used in OSPF to choose the best route from all candidate routes learned through OSPF.

Administrative distance is a measure of the trustworthiness of the routing information source. It is a value used by a router to choose between multiple known routes that have been learned from different routing sources, such as different routing protocols. When routes are learned from the same routing protocol, their administrative distance will be equal, and the router will then choose the route with the lowest metric value of the routing protocol. In this case, that metric is the OSPF cost.

The composite metric is the metric used by EIGRP to choose a route when multiple routes have been learned by EIGRP. Hop count is the metric used by RIP to choose a route when multiple routes have been learned by RIP.