面向基于位置服务的一种改进型隐私感知虚假位置选择机制

An Improved Privacy-Aware Dummy Location Selection Scheme in LBSs

基于位置的服务已经逐渐成为人们生活中的重要部分,然而在无线信道中传输位置信息容易受到各种攻击,导致严重的隐私泄露问题。为此,本文考虑隐私保护等级以及实际虚假位置区域,将虚假位置选择问题建模为多目标优化问题,进而提出一种低复杂度的隐私程度可控的虚假位置选择机制。本文首先从候选虚假位置中选择出请求率差异在指定范围内的虚假位置,保护一定的隐私等级,然后从中找出K-1个虚假位置,最大化总泛化面积。为了更准确确定总泛化面积,本文推导出两位置区域的相交面积。安全分析验证了本文提出的算法可以对抗主动攻击以及被动攻击。与其他算法相比,仿真结果也证明了本文提出的算法可以在保护用户隐私等级的情况下增大总泛化面积。

Location-Based Service （LBS） becomes increasingly important for our daily life. However, the localization information in the air is vulnerable to various attacks, which results in serious privacy concerns. To overcome this problem, we formulate a multi-objective optimization problem with considering both the query probability and the practical dummy location region. A low complexity dummy location selection scheme with the controllable privacy level is proposed. For preserving the privacy level, we first find several candidate dummy locations with various query probabilities, whose dif- ferences from the query probability of the real user is within a specified threshold. Among these selected candidates, a cloaking area based algorithm is then offered to find the remaining K-1 dummy locations to maximize the cloaking area. The intersected area between two dummy locations is also derived to assist to determine the total cloaking area. Security analysis verifies the effectiveness of our scheme against the passive and active adversaries. Compared with other methods, simulation results show that the proposed dummy location scheme can improve the privacy level and enlarge the cloaking area simultaneously.