APPLAUS: A Privacy-Preserving Location Proof Updating System for location-based services

TLDR

Location‑based services depend on mobile devices to report their position, but this allows users to spoof locations and gain unauthorized access. This paper proposes APPLAUS, a privacy‑preserving location‑proof updating system that lets co‑located Bluetooth devices generate and exchange proofs to prevent such spoofing. APPLAUS uses periodically changing pseudonyms to protect source location privacy, and a user‑centric model that lets users assess privacy levels in real time before accepting proof exchanges. Experiments show that APPLAUS can be deployed on existing infrastructure with minimal computation or power cost while effectively preserving source location privacy.

Abstract

Today's location-sensitive service relies on user's mobile device to determine its location and send the location to the application. This approach allows the user to cheat by having his device transmit a fake location, which might enable the user to access a restricted resource erroneously or provide bogus alibis. To address this issue, we propose A Privacy-Preserving LocAtion proof Updating System (APPLAUS) in which co-located Bluetooth enabled mobile devices mutually generate location proofs, and update to a location proof server. Periodically changed pseudonyms are used by the mobile devices to protect source location privacy from each other, and from the untrusted location proof server. We also develop user-centric location privacy model in which individual users evaluate their location privacy levels in real-time and decide whether and when to accept a location proof exchange request based on their location privacy levels. APPLAUS can be implemented with the existing network infrastructure and the current mobile devices, and can be easily deployed in Bluetooth enabled mobile devices with little computation or power cost. Extensive experimental results show that our scheme, besides providing location proofs effectively, can significantly preserve the source location privacy.