SACS:一种可扩展的匿名通信系统

SACS: a Scalable Anonymous Communication System

匿名通信的主要目的是隐藏通信双方的身份或通信关系,从而实现网络用户的个人通信隐私及对涉密通信更好的保护.目前匿名系统的研究主要在于提高匿名性能,许多原型系统借助于多个代理的重路由技术、填充包技术和加密技术来达到匿名发送或匿名接收的目的.而当匿名系统真正要被应用于现实网络中时,系统管理方式和管理代价直接会影响到系统的可扩展性.目前的许多匿名原型系统采用集中式管理机制,不能承受大量用户的存在,因此都无法应用于大规模的网络环境中.本文基于Crowds系统,提出了一种新的匿名通信系统SACS的结构与协议描述,引入了分区域管理机制,实现了对系统内成员的分布式管理,有效地降低了匿名系统的管理开销,具有很好的可扩展性.概率分析与测试结果表明新的系统在减少系统的附加管理开销、支持良好扩展性的同时保持了与原Crowds系统相当的匿名性.

The main purpose of anonymous communication system is to conceal sender, receiver or relation of communication, protecting the privacy of person or some special organization. There have been some researches on improving anonymity degree in some prototype system, using technologies such as rerouting, padding and encrypting, but most of them ignore the cost for management in system, which are not able to support large quantities of users and restrain the Scalability of system in realization. This paper proposed a new architecture and protocol of anonymous communication system based on Crowds system. Using distributed domain-managing scheme, the system make its members be managed by different servers. So, the cost for management in the system can be decreased obviously and the system can scale well in real network. Both results of probability analysis and simulation indicate that the new system can keep almost the same anonymity with Crowds while scaling well and decreasing the cost obviously.