Alloyed Pseudonym Change Strategy for Location Privacy in VANETs

Ensuring safety in vehicular ad hoc networks (VANETs) requires the connected vehicles to exchange real time accurate road information. However, this necessity risks the privacy and may violate the user's confidentiality. The periodically broadcasted beacon messages containing the vehicle's spatiotemporal road information, and signed using the vehicle's temporal public key are the main factors leading to that risk. Since these factors are fundamental for the correct functioning of a vehicular network and, hence, cant’ be ignored, a solution that preserves the location privacy is needed. In this paper, we aim to preserve the location privacy through a robust pseudonym change strategy that ensures the unlinkability. The proposed method confuses the attacker at the pseudonym update phase to thwart the linkability. It combines the “hiding within the crowd” and the “location obfuscation” techniques. The simulation results of the proposed scheme illustrate a high protection level against a global passive attacker executing semantic and syntactic linking attacks. This is further emphasized through the established comparative study.