网络匿名度量研究综述

保护网络空间隐私的愿望推动了匿名通信系统的研究，使得用户可以在使用互联网服务时隐藏身份和通信关系等敏感信息，不同的匿名通信系统提供不同强度的匿名保护，如何量化和比较这些系统提供的匿名程度从开始就是重要的研究主题，如今正得到更多关注，成为新的研究焦点，需要开展更多的研究和应用.匿名度量可以帮助用户了解匿名通信系统提供的保护级别，帮助开发者在设计和改进匿名通信系统时提供客观和科学的依据.给出了匿名度量研究的通用框架，包含匿名通信、匿名攻击和匿名度量三个部分及其相互关系.综述了匿名度量领域的研究工作，寻找其发展脉络和特点，按时间线回顾和归纳基于多种理论和方法的匿名度量标准，结合匿名通信攻击技术对典型的度量方法各自的特点和相互关系进行梳理和比较，介绍度量研究新的进展，展望研究的下一步方向和发展趋势.分析表明，匿名度量有助于判断匿名通信系统是否提供了所承诺的匿名性，用于表达匿名程度的度量标准越来越多样，基于信息论的度量方法应用最为广泛，随着Tor等匿名通信系统的大规模部署，出现了基于统计数据针对真实系统和基础设施进行的匿名性评估.随着匿名技术的新发展，如何扩展度量标准应用于新出现的匿名技术，如何组合度量标准以适用于新的匿名系统，都是有应用前景的研究方向.

Survey on Anonymity Metrics in Communication Network

The desire to protect privacy in cyberspace has promoted the design of anonymous communication systems. Anonymity ensures that users do not expose sensitive information such as identity and communication relationship when using Internet services. Different anonymous communication systems provide different strength of anonymity protection. How to quantify and compare the degree of anonymity has been an important research topic since its beginning. And now it is getting more and more attention, and becoming a new research focus, more researches and applications are necessary to be carried out. Anonymity metrics can help users understand the levels of protection achieved through anonymous communication systems, and help developers gain objective and scientific basis for designing and improving anonymous communication systems. A general framework for anonymity metrics research is presented, including anonymous communication technology, attacks against anonymous communication technology, anonymity metrics, and their relationships.This paper surveyed the researches in anonymity metric field, looking for their development and characteristics. A variety of theories and methods of anonymity metrics were reviewed and summarized following the time line. Considering attacks against anonymous communication, the characteristics and mutual relations of typical metric methods were sorted out, analyzed and compared. And the new progresses were introduced, looking forward to the research direction and development trend. The analysis shows that anonymity metrics help to determine whether anonymous communication systems can provide promised anonymity, the metrics are becoming more diverse, and the metrics based on information theory are the most widely used. With the large-scale deployment of anonymous communication systems such as Tor, evaluations for real practical systems and infrastructures based on statistical data have emerged. New anonymous technologies have been developed rapidly recently, how to extend the metrics to the emerging technologies and how to combine different metrics to adapt to the emerging systems are the new research directions with good application prospects.