Spatial Cloaking Revisited: Distinguishing Information Leakage from Anonymity

Abstract. Location-based services (LBS) are receiving increasing popularity as they provide convenience to mobile users with on-demand information. The use of these services, however, poses privacy issues as the user locations and queries are exposed to untrusted LBSs. Spatial cloaking techniques provide privacy in the form of k-anonymity; i.e., they guarantee that the (location of the) querying user u is indistinguishable from at least k-1 others, where k is a parameter specified by u at query time. To achieve this, they form a group of k users, including u, and forward their minimum bounding rectangle (termed anonymizing spatial region, ASR) to the LBS. The rationale behind sending an ASR instead of the distinct k locations is that exact user positions (querying or not) should not be disclosed to the LBS. This results in large ASRs with considerable dead-space, and leads to unnecessary performance degradation. Additionally, there is no guarantee regarding the amount of location info...

• Type: Conference
• Year: 2009
• Where: SSD
• Authors: Kar Way Tan, Yimin Lin, Kyriakos Mouratidis
• Keywords: Database, Minimum Bounding Rectangle, Spatial Cloaking, Spatial Cloaking Techniques, SSD 2009