Query-Privacy-Aware Location Cloaking for Mobile P2P System

Location-based Services (LBS) have brought the potential threats of mobile users’ sensitive personal information. Privacy-aware in LBS is including location privacy and query privacy. Unfortunately, existing privacy protection algorithms rarely pay attention to both of them. This paper proposes a novel privacy protection method which combines K-anonymity and L-diversity to protect both location privacy and query privacy. Two effective queryprivacy-aware methods are introduced into the cloaking algorithm. One is the history sharing scheme which confuses history queries within tolerance time. Another is the batch query scheme which confuses real queries presented by the peers. Our technique is suitable for P2P mobile networks, which can effectively eliminate the bottleneck of system brought by the anonymizer. In addition, we develop an imprecise location scheme to prevent the inference attack of few malicious peers. The experiments show that the proposed algorithms are effective to protect users’ location privacy and query privacy in the mobile P2P system.