Location Privacy: User-Centric Threat Analysis

Information that describes the geographic locations of a person over time is a fairly new class of potentially privacy-harming data. In pace with certain technological advances of the recent years, more and more location data is generated and processed by various systems. Its usage for different location-based services (including the integration into social network services) encounters a steep and still ongoing rise in popularity. Besides communication infrastructure based localization methods that map IP-addresses, GSM-cell identifiers or wireless router MAC-addresses to geographic locations, the main contribution to this development comes from the proliferation of GPS-enabled mobile user devices. The critical point is that plain location data has the potential to both identify a single user and disclose sensitive information about that user's activity at the same time. This makes the robust anonymization of position information a non-trivial task and has created a lively branch in privacy research over the last years.