Privacy-Preserving Location Tracking of Lost or Stolen Devices: Cryptographic Techniques and Replacing Trusted Third Parties with DHTs

摘要

We tackle the problem of building privacy-preserving device-tracking systems - or private methods to assist in the recovery of lost or stolen Internet-connected mobile devices. The main goals of such systems are seemingly contradictory: to hide the device's legitimately-visited locations from third-party services and other parties (location privacy) while simultaneously using those same services to help recover the device's location(s) after it goes missing (device-tracking). We propose a system, named Adeona, that nevertheless meets both goals. It provides strong guarantees of location privacy while preserving the ability to efficiently track missing devices. We build a version of Adeona that uses OpenDHT as the third party service, resulting in an immediately deploy-able system that does not rely on any single trusted third party. We describe numerous extensions for the basic design that increase Adeona's suitability for particular deployment environments.