Abstract: Link State routing protocols do not view networks in terms of adjacent routers and hop counts. Using the SPF algorithm, the router creates a "topological database“. OSPF and IS-IS, split traffic evenly over shortest paths based on link weights. However, optimizing the link weights for OSPF/ IS-IS to the offered traffic is a well-known NP-hard problem, and even the best setting of the weights can deviate significantly from an optimal distribution of the traffic. A new link-state routing protocol, PEFT that splits traffic over multiple paths with an exponential penalty on longer paths. The survey shows the best routing algorithm by comparing the previous results with the algorithms named as link state, hop by hop, optimal and adaptive.

Keywords: Link State, Hop by Hop, Optimal, Adaptive.