Third party positioning services: novel challenges for location privacy in LBS

Acommon assumption in the research community working on location privacy in locationbased services (LBS) is that the location sources are trusted. In this paper we present a different perspective. We argue that, because of the deployment of wifi-based/hybrid positioning techniques and web-based LBSs, the user’s location is increasingly computed by third-party location providers which may be not fully trusted. This change of perspective challenges the effectiveness of current location privacy-preserving techniques. To support this thesis we present an empirical investigation of the privacy issues raised by web-based LBSs. Moreover, following a holistic approach, we present the problem from three different and complementary angles, i.e., technical, user-based, and legal. The overall picture suggests a novel direction of research.