Research On Re-Routing Mechanism In Anonymous Communication System

The Internet has become a platform for worldwide information dissemination and resource sharing, but many attendant problems have increasingly emerged. How to protect information security and personal privacy is a critical issue.Anonymous communication technology which gets more and more attention now, is an important means to protect an information security and personal privacy, it can meet the both needs of continuously improving individual privacy standard and those of the escalating requirements of network security for the National military, Defense and other related departments, it is increasingly widespread concerned.At present, an important one of the used anonymous communication technologies is the re-routing technology. However, most systems based on the re-routing technology encrypte middle node's information with public key in a nested way and use filled techniques to confuse the input and output of a message, the result of the pursuit of strong anonymity brings a large network overhead. Most of the re-routing techniques use the randomized strategy, the randomly selected relay will bring the corresponding delay as they're geographically far apart, it is difficult to achieve reliable and efficient service. The main research work in the thesis is how to balance both of the anonymity and efficiency of anonymous systems, the main content of the research and innovations are as follows:Firstly, we have reviewed of the development history of anonymous communication and summarized anonymous communication protocols. For the case that the attackers concentrated area will reduce the system's anonymity, the group-routing strategy is put forward, it can disperse the attackers' targets, enhance the system's anonymity and reduce the system's failure rate of the communication at the same time.Secondly, in order to greatly enhance the performance of the system, the re-routing is combined with the trust mechanism to motivate the good behaviors and the malicious acts of system members. The routing decisions evaluating system members based on the reputations can not only improve the anonymous system's efficiency, but also enhance its anonymity. Finally, a new improved simulated anonymous system is designed and implemented. It enhances anti-attack by the nested encryption, enhances the system's anonymity through the group-routing strategy, improves the system's efficiency through the trust model, and then combines practicality and anonymity and efficiency well.