Reseach On Infrastructural Information Filtering System Based On Software Defined Network

Nowadays, many organizations are more and more devoting into the research of information filtering system. In particular, as the information security issue comes back into people’s sight again, our nation is accelerating the updating of communication security strategy. Both the monitoring and the analyzing of Internet information play huge roles in information security. Besides, information filtering technology is also the foundation of forbidden information blocking and accessing-oriented management in common networks. So far, most of the information filtering systems are implemented at the users’ end, and a small number of information filtering systems are at servers’ end. All of the systems are not completely adaptive to the various practical situations, due to the regardless of security in data forwarding. Because of the defects on their own, the systems are easy to bypass despite the improvement on accuracy brought with the developing of algorithms. So the information filtering systems can not fulfill the demand of networks. Especially when the status of networks is changing, and the content of information is complicated, the systems are not conveniently re-configurable. However, the invention of SDN(Software defined network) gives us a new prospective of information filtering system. The framework of SDN outlines a forwarding-layer-based information filtering system. This dissertation starts with analyzing the requirements of information filtering, describes the design of information filtering module based on SDN, which can be configured by SDN controller to be adaptive to different applications. For being implemented in forwarding plane, it is not possible to bypass by users’ behavior.Our work includes following content: 1. Analyzing the framework of common information filtering systems, and summarizing the features of the most representative ones. 2. Analyzing the theories regarding information filtering, including string-match algorithms, information classifying algorithms. 3. A brief introduction to SDN, describing the combination of information filtering and SDN framework. 4. Aiming at the functional requirements, we accomplished designing of the information filtering system for OpenFlow formatted data packet. The system supports both accessing-oriented filtering and content-oriented filtering. 5. Build the testing environment, doing tests for all the functions realized in the system.