Private Contact Tracing on Trajectory Data

Private contact tracing (PCT) has been used in many applications including healthcare, crime investigation, and bureaucracy. In this paper, we present a privacy-preserving trajectory-based PCT scheme. Unlike Bluetooth-based contact tracing, where the contact detection decision is made on each device, the proposed scheme performs the contact detection decision on the server using a trusted execution environment (TEE). The proposed PCT scheme preserves privacy of the users. The scheme is experimented on Intel Software Guard Extensions (SGX) platform and the experimental results demonstrate its practicality in real-world applications.