Research And Application Of Network Monitor

With the development of network technology of computer, the school has possessed the environment of the network, have launched online teaching,handle official business with no paper at all,online teaching,etc. While the network technology is giving people every aspect of living, working to bring convenience and swift, have brought the threat of the security of the network too. The illegal computer system is invaded,stolen,distorted, destroyed the important data,not only caused losses hard to assess, at the same time but also the application more extensive for information technology placed obstacles.The online security question of campus network becomes more and more outstanding too. The online security of the campus becomes a kind of urgent demand more and more.Therefore, the demand for tools that can analyze, diagnose and test the network performance and security has been increasing, the paper main content is:First.This paper expounds the concept of network monitoring technology, namely the use of computer network interface destination for other computer intercept data message.Secondly,this dissertation introduced how the network monitoring technology-works, giving a thorough analysis on the system architecture, the theory and the main functions of WinPcap development pack. WinPcap, one of the little free software that supports the capture interface with great functions, is the basis on which the real-time testing system is able to capture data. In the environment of Win32, the system uses the library of WinPcap to capture and filter the data packet before it makes a protocol analysis on the captured data.distinctly manifesting the fields of each packet to the user. Meanwhile, it can seize the current state of the network timely as it monitors the local network in real time. Other than the functions mentioned, the system can also perform some specific tasks, for example, automatically giving an alarm when sentimental keywords or illegal IP activities occur, detecting monitor and checking traffic as well.Then followed the basic steps and methods to use WinPcap library to realize the goal of monitoring the network in real time along with the ways to optimize the system.Thirdly,We describe the actuality and future of the network monitoring development.And the design idea of the monitoring under WAN is provided. We analyze the model of capture and filter and the method of protocol analysis in detail. We summarize the factors that affect the efficiency of capture and provide protocol analysis way of two level.Finally,the application example of the school’s monitoring is given, the conclusion on the whole process of the researching and developing is presented, pointing out the problems still existing in the system and the outlook to the future work.