Link State Routing Protocols
Link state protocols also fall into the classless category of routing protocols, and they work within packet-switched networks. OSPF and IS-IS are two examples of link state routing protocols.
Remember, for a protocol to be a classless routing protocol, the subnet-mask information must be carried with the routing update. This enables every router to identify the best route to each and every network, even those that don’t use class-defined default subnet masks (i.e., 8, 16, or 24 bits), such as VLSM networks. All neighbor routers know the cost of the network route that’s being advertised. One of the biggest differences between link state and distance vector protocols is that link state protocols learn and maintain much more information about the internetwork than distance vector routing protocols do. Distance vector routing protocols only maintain routing tables with the destination routes and vector costs (like hop counts) in them. Link state...