The Research Of Topology Discovery And Attack Detection Technology Based On OSPF Protocol

With the rapid development of the internet, our social has entered into the age of network, large-scale application of the network promotes the spread of information and the development of the society. Routers are the infrastructures of the network and routing protocol is an important part of the internet. Exchange of information between different regions through routers and other equipment, routing protocol is an important method to regulate these communications.The OSPF protocol which is a distributed link state protocol, it is one kind of the most widely used intra-domain routing protocol which has the advantages of fast rapidity of convergence, low network traffic and non-routing loop at the current.This paper paied close attention to topology discovery and attack detection based on OSPF protocol.Firstly, this paper introduces some basic knowledge of OSPF protocol; Secondly, a new algorithm of real-time network topology discovery based on OSPF protocol has been proposed, the algorithm uses a passive packet capture method can obtains the information of network topology such as the relationship of the links between routers without making influence of network by analyzing the Router-LSA and Network-LSA, it has high accuracy and good real-time performance. Thirdly, this paper described the attack detection method based on feature recognition by analyzing the security mechanism and vulnerability of OSPF protocol in detail. Finally, we finished the design and implementation of a routing attack detection system based on the topology discovery algorithm and attack detection method proposed before, then described detailed the modules and the implement method of the system. After that, we used some related operation to test the function of the system. In the end, the testing result shows that, the system can get a complete and accurate network topology in a short period of time and have the real-time attack alarms.