Readjusting the privacy goals in Vehicular Ad-Hoc Networks: A safety-preserving solution using non-overlapping time-slotted pseudonym pools

Abstract

Current proposals for privacy measures in vehicular networking commonly suffer from either of three limitations: Many are so drastic that they compromise road traffic safety, a primary goal of vehicular networks. Others are more compliant, but (despite adding substantial overhead) are ineffective at protecting users’ privacy against state-of-the-art attackers. The last group suffers from neither limitation, but undermine accountability and are thus in conflict with the requirements of future vehicular networks. As a consequence, workable privacy protection is often thought unattainable and privacy protection simply disregarded in the many field experiments, proposals, and standardization documents to date. In this work, we start fresh with a readjusted view on privacy goals and the capacities of a state-of-the-art attacker in mind, taking a structured approach to deriving a holistic solution for location privacy protection in Vehicular Ad-Hoc Networks (VANETs): We show that local privacy protection cannot be attained without compromising road traffic safety – nor does it have to be. Our approach is based on synchronized time-slotted pseudonym pools and the local announcing of pseudonym changes. By this, we overcome the privacy–safety problem while at the same time increasing privacy for all users. Our system is fully compatible with the requirements of vehicular networks and current standardization efforts.