Which routing protocol uses hop count as a metric for path selection?

The routing protocol that utilizes hop count as a metric for path selection is RIPv2 (Routing Information Protocol version 2). This protocol is a distance-vector routing protocol, and it measures the distance to a destination in terms of hops, with each hop representing a router that data must pass through. RIPv2 limits the number of hops to a maximum of 15, which means that if a destination is more than 15 hops away, it is considered unreachable.

RIPv2's use of a simple metric such as hop count allows for easier implementation and understanding, especially in smaller networks. However, this can also lead to limitations in larger and more complex networks due to the lack of consideration for factors such as bandwidth or link latency, which other protocols like OSPF or IS-IS take into account. Thus, the distinct approach of RIPv2, focusing solely on hop count, clearly distinguishes it in the landscape of routing protocols.