Hangout: A Privacy Preserving Location Based Social Networking Service

As mobile devices enter a new era with high speed connectivity and increasing compute capabilities a new class of applications called social networking applications is being showcased as the next revolution in mobile computing. In this class of applications each user in a social group contributes their knowledge about their surrounding environments and the collective knowledge can then be exploited by the group members for a personal or social benefit. As the popularity of mobile social networks increases there is a growing realization that information collected about an individual user can compromise one's privacy and potentially security. It is in this context we developed HangOut a privacy preserving social networking application. Hangout protects user’s private information not only from other malicious users but even from system administrators who may have unrestricted access to the backend server that is providing the social networking service. Hangout uses location and time distortions, symmetric key encryption where the keys are exchanged in a peer-to-peer fashion and several client side controls to aggressively protect privacy with minimal degradation in user’s perceived service value.