Which dynamic routing protocol uses a cost based on interface bandwidth as its metric?

Open Shortest Path First (OSPF) is a dynamic routing protocol that utilizes cost as its metric, which is determined based on the bandwidth of the interfaces. OSPF calculates the cost for each route by using the formula: cost = 100,000,000/bandwidth in bits per second. This means that higher bandwidth interfaces will result in a lower cost, making them more preferable for routing decisions. By considering bandwidth, OSPF can effectively choose the most efficient path through a network.

In contrast, other dynamic routing protocols use different metrics for path selection. For instance, Routing Information Protocol (RIP) uses hop count as its metric, which does not factor in the bandwidth of the links. Enhanced Interior Gateway Routing Protocol (EIGRP) employs a Composite Metric that considers bandwidth, delay, load, and reliability, but it does not exclusively base its calculations solely on bandwidth. Intermediate System to Intermediate System (IS-IS) also uses a metric system that can be configurable but does not inherently focus on bandwidth in the same way that OSPF does.

Thus, OSPF's use of interface bandwidth as a basis for its cost metric makes it distinct among these options, leading to more optimized routing decisions that prioritize high