Research On Simulating Border Gateway Protocol

In recent years, the Internet has already penetrated into all aspects of our life, while Internet research has become a hot. As a standard protocol between Autonomous System in fact, BGP obtains extensive research because of its importance. Compared to measurement and analysis research means, network simulation is low cost, simple, and have a certain degree of authenticity, can perform details of network protocols, and can guarantee a certain scale. It is widely used in the protocol studies. Because BGP involve large-scale network and complex topology, the main way to study BGP is using simulation.Currently, the problem with BGP simulation is poor efficiency because BGP itself is complex and the complexity directtly affects simulation results.This paper first summarizes the overall current BGP simulations, including the convergence time and BGP routing strategy. We discuss the relationship between these factors and BGP simulation efficiciency and analyze the reasons for poor effeciency. And we introduce some techniques to improve simulation efficiency by reducing BGP simulation memory consumption. Second, we elaborate BGP routing strategy simulation, and implement BGP simulation system based on NS-2 by modifying Zebra bgpd module. Finally, we invent some optimized simulation strategies (including deleting TCP characteristics, changing the KeepAlive-Notisfication way and improving route search algorithm). Through these promotions we improve simulation efficiency. It is proved by experiments that these optimized strategies can reduce our simulaton time by approximate 85% and reduce simulation events by about 95%.