Which routing protocol typically uses more CPU resources on a router?

Link State routing protocols are known for typically using more CPU resources compared to other types, such as Distance Vector protocols. This is primarily because Link State protocols maintain a full and comprehensive view of the entire network topology. Each router participating in the protocol constructs a complete map of the network by exchanging Link State advertisements (LSAs) with other routers.

This process involves several resource-intensive tasks, like calculating the shortest path to each destination using algorithms such as Dijkstra's algorithm. Since each router must process LSAs from all other routers to maintain accurate network topology information, link state protocols demand more processing power and memory.

In contrast, Distance Vector protocols, like RIP, rely on simpler calculations based on distance metrics and only share information about routes they know directly with neighboring routers. This less complex method generally requires fewer CPU resources because it does not need to maintain an entire view of the network and perform extensive computations.

Considering the various routing options, Link State protocols stand out for their increased resource usage, making this the correct choice for the question.