Network Traffic Monitoring System Based On SNMP And JAVA

Network management is related to lots of aspects in running of networks, and has become one of the most important contents in the current information networks. Of the network management, traffic monitor, statistically analyzing are the most fundamental parts. They are the basis of network management, which can effectively help administrators make performance management, accounting management, fault management and make proper decisions. WBM (Web based management) is a combination of network management technology and web technology. It offers greater power than traditional tools in management. Administrators can detect and control their networks from any places and from any Web browsers. Management is not limited to the network management stations as usual. Java plays an important role in WBM, which is an object-oriented interpretive language with a famous slogan "compile once, run everywhere" and is very suitable to write distributed network management software.This thesis brings forward a method to monitor the traffic load on network-links. Firstly, network traffic data are acquired through SNMP protocols. Then the traffic data are stored in the RRD (Round Robin Database) files and GIF graphs are made in the end (PNG and JPEG formats are supported). Besides the daily traffic graphs, it also creates visual representations of the traffic during the last seven days, the last four weeks and the last twelve months. These graphs can be embedded in the HTML files which are present to administrators visually.Following the method mentioned above, I implement a network traffic monitor system. Its two prior advantages over other systems are "free of configuration" and cross-platform. "Free of configuration" means that without writing or modifying any configuration files, just through web pages, administrators can add or delete devices under management. Through web pages, administrators can freely select or adjust the interfaces to be monitored. In addition, the system is written in Java, acquiring the cross-platform ability. It can run under Unix/Linux. Without any change, it can also run under Windows NT/2000, Windows XP.Applying the MVC model, the system has a clear architecture. Servlet plays apart as controller, Jsp as View and Javabean as model. The business logic is implemented completely in Javabeans, so these codes can be exported to non-web based network management easily. In order to make up for the defect of web technology - weak in real time reactions, Applet is used in client's part. Applet makes a connection to the server actively, so mutual communications are established. The server applies NIO (the new I/O). Only one thread is needed to keep connections with all the clients. In this way, the server is relieved notably and efficiency is improved.Facts prove that the traffic monitor system making use of SNMP and Java is easy to use and portable. And the good architecture ensures the code is reusable and extensible. So, it possesses great practical value for application.