Abstract: In order to cope with the problem that the adversary can identify the real location of the user in continuous query service, in spite of the utilization of privacy protection method of distributed system architecture. This paper proposes a cell uncertainty extension method to provide location privacy protection for continuous query. This method utilizes the cache of collaborative users who located in the uncertainty continuous region to provide services for neighboring users, then reduces the direct interaction about information between the user and the service provider during the whole process of continuous query service. Furthermore, this method also leads the result of that the untrusted service provider cannot obtain enough information about the user to initiate the attack for users identification, and then provides a better privacy protection service for the user. At last, this paper utilizes the security analysis to verify the privacy protection level of the proposed method, and then utilizes the experimental verification to further verify the security of the proposed method as well as its execution efficiency.

Key words: location-based services, privacy protection, users collaboration, uncertainty extension

摘要： 针对分布式系统架构的基于位置服务隐私保护方法在连续位置查询服务中可能会受到的差异识别攻击，提出了一种单元格不确定性扩张的连续匿名区域隐私保护方法。该方法通过连续匿名区域内的协作用户缓存查询结果，并提供给需要同类查询结果的邻近用户的方法，降低申请者在整个连续位置查询服务的过程中与位置服务提供商之间的直接信息交互量，使得不可信的服务提供商无法获得足够的申请者信息来发动差异识别攻击，最大程度地保护了申请者的位置隐私。最后，通过安全性分析验证了所提出方法的隐私保护能力，同时利用实验验证进一步证明了该算法的安全性和执行效率。

关键词: 基于位置服务, 隐私保护, 用户协作, 不确定性扩张