The Research Of Distributed Bgp Protocol Based On SDN Hierarchical-Controller

Border Gateway Protocol is mainly responsible for exchanging network layer reachable information with other BGP systems as a routing protocol between autonomous systems. However, with the explosive growth of the Internet and the more complex network applications, the storage and computing ability of BGP should be improved obviously. in order to address the problems, such as the sharp increase of the BGP peer session、the burst of route update and the routing jitter, In this paper, we propose a distributed BGP protocol mechanism based on SDN hierarchical controller combined with the method of downloading function, and research its related theory and technology.Firstly, the paper introduces the background, future trends of SDN distributed controllers and distributed BGP protocol, the process of BGP protocol, the architecture design of the hierarchical controller and implementation of the hierarchical controller. Furthermore, we propose hierarchical architecture of distributed BGP protocol based on the analysis of BGP protocol’s function modules, and download functions from route calculation module which is not involved of global state innovatively, thereby improving the computing and storage performance of BGP protocol. Based on this architecture, through the interaction with local controllers and global controller, we propose the scheme of distributed BGP protocol so as to ensure the BGP protocol to handle more BGP session of peers thereby improving the scalability. Additionally, we present a hierarchical BGP protocol algorithm to classify according to BGP session of peers, to cut the routing synchronization information of the internal BGP’s system, thereby achieving synchronization between global controllers. Then, we establish the Petri’s performance model of the hierarchical BGP protocol, solving and testing the throughput rate of update packets, CPU utilization rate and other data from hierarchical BGP protocol so as to evaluate system performance.Finally, testing the three indicators of performances such as the scalability of peer session, routing update rate and route convergence time. Compared by the traditional BGP system, the SDN hierarchical BGP system has more advantages on system scalability, route learning ability and routing efficiency, which illustrates the superiority of the distributed BGP architecture based on hierarchical controller.