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LPA: a new location-based privacy-preserving authentication protocol in VANET

In this paper, we introduce a location-based privacy-preserving authentication protocol (LPA) in vehicular ad hoc networks (VANETs) to address the issue on conditional privacy preservation in which safety messages can be anonymously authenticated by peer vehicles while an authority can trace the sender in a dispute. Specifically, in the LPA protocol, we propose a top-down security system: the top authority (TA) authorizes the roadside units (RSUs) to issue group certificates to the onboard units (OBUs). In addition, we also introduce RSU neighbor set to enhance security and efficiency. We demonstrate the merits of the proposed scheme through extensive analysis and performance evaluation. Copyright © 2011 John Wiley & Sons, Ltd.