Link state routing protocol is more suitable for large networks, but because of its complexity, making the router needs more CPU resources. It can find disconnected links or newly connected routers in a shorter period of time, making the convergence time of the protocol shorter than that of the distance vector routing protocol. Normally, when no HELLO packet is received from the neighboring station within 10 seconds, it considers that the neighboring station is unreachable. A link-state router sends an update message to its neighbors informing it of all the links it knows about. It determines the metric of the optimal path as a numerical cost, the value of which is generally determined by the bandwidth of the link. The link with the least cost is considered optimal. In the shortest path first algorithm, the value of the maximum possible cost can be almost infinite.

If there is no change in the network, the router periodically refresh the routing table is not updated on it. Link state routing protocols are as follows: IPOSPF, IPXNLSP and IS-IS.

Can a router use both a distance vector routing protocol and a link-state routing protocol? Each interface can be configured to use different routing protocols; however, they must be able to exchange routing information by redistributing routes.