Question: is is routing protocol vs ospf?
Answer: Comparison with OSPF. Both IS-IS and Open Shortest Path First (OSPF) are link-state protocols, and both use the same Dijkstra algorithm for computing the best path through the network. ... While OSPF was natively built to route IP and is itself a Layer 3 protocol that runs on top of IP, IS-IS is an OSI Layer 2 protocol.