The complex behavior of the open shortest path first(OSPF) algorithm was modeled using a stochastic Petri net.The model was simplified by removing the time-consuming part of the analysis from the OSPF algorithm.The simulation results show that the OSPF algorithm performs differently for different network state.When the network changes frequently,the OSPF load is focused on routing calculations, but when the network is stable,the OSPF load is focused on searching the link state advertisement.This paper provi...