MPSL: A Mobile Phone-Based Physical-Social Location Verification System

In this paper, we introduce a new concept, Physical-Social Location (PSL), and propose MPSL, a mobile phone-based system to verify users’ self-report location claims for mobile social network service (MSNS). Unlike instant discrete location points, PSLs are geographic regions obtained over longer timescales and center around regularly visited locations of social significance, e.g., workplaces or neighborhoods. PSL verification can prevent the user from reporting fake locations, e.g. GPS coordinate, trajectory or geographic profile, to location-sensitive applications as well as aid online credibility in MSNS. In our MPSL system, a user’s location claim is proved by a set of selective co-located people serving as ”witnesses”. It is composed of two parts, i.e., proof generation and verification. The former leverages a certain number of co-located people to generate co-location certificates as location proofs during their physical encounters via Bluetooth. An efficient verification scheme is proposed to make our system accurate and adaptive. Besides, incentive are taken into account to keep our distributed system applicable. We have implemented the MPSL system using real-world Nokia N82 phones. Our experimental results show that our mobile phone based system can achieve high verification accuracy and good privacy protection.