Privacy-Preserving Location-Based Service in Internet of Vehicles via Oblivious Transfer in Zero-Trust Framework

The dynamism and heterogeneity inherent to the internet of vehicles necessitate its operation within a zero-trust environment. Serving as a vital element in location-based services (LBSs), geographic information is imperative to ensure the proper functioning of navigation, traffic updates, courier service, etc. Location data can potentially reveal extensive personal information of a user, such as social relationships, habits, and health conditions. To alleviate the conflicts amongst privacy, data property, and real-time performance for an LBS in the Internet of Vehicles, a secure point-of-interest information retrieval scheme is presented in this paper. We developed a lightweight fully homomorphic encryption algorithm based on the hardness of the discrete logarithm conjugacy search problem (DLCSP) and implemented it as an oblivious transfer (OT) protocol that not only conceals the query but also safeguards the data assets of the server. The effectiveness of our proposed method was validated experimentally. The results showed that our scheme outperformed state-of-the-art methods in terms of both computation and communication overhead, particularly on the server side. In addition, a simulation-based security validation demonstrated that our scheme is more robust when defined as an OT.