A Privacy-Preserving Mechanism for Requesting Location Data Provider with Wi-Fi Access Points

With the democratization of mobile devices embedding different positioning capabilities, the location of users is now collected to track the location of users. When used for behav-ioral profiling, this tracking for enhancing raises more and more privacy concerns.Depending on the permissions, mobile applications can get a fine-grained user's location from the GPS or a coarse-grained location by requesting location data provider with surrounding Wi-Fi access points for instance. While using the GPS does not rely on external untrusted party, requesting a location data provider clearly exposes the location of users. Whereas location privacy has been an active research field this last decade, most of the contributions are performed on GPS-based data, and it is not clear how to efficiently protect Wi-Fi-based positioning to preserve the users' privacy. In this paper, we propose a novel solution to preserve users' privacy from curious location data providers when requesting users' location from Wi-Fi while supporting high-utility. The key idea behind our online approach is to combine a random sampling (for controlling the quantity of revealed information) and a obfuscation scheme (for ensuring privacy-preserving information disclosure). We exhaustively evaluate our solution with a real dataset of mobility traces collected through multiple sensors. We show that the proposed approach provides a trade-off between privacy (i.e., avoiding to reveal its true location) and utility (i.e., still benefiting from services such as places recommendation) fully control-lable by the users. Lastly, we also discuss the integration of our protection scheme in mobile operating systems.