Privacy-preserving authentication scheme with full aggregation in VANET

Abstract Vehicular Ad-hoc Network (VANET) is the fundamental of intelligent transportation systems. Security and privacy are the important issues needed to be addressed. Existing schemes for privacy-preserving vehicular communications face many challenges, such as strong assumption on ideal tamper-proof device (TPD) and reducing the cost of computation and communication. In order to overcome the challenge, we propose a privacy-preserving authentication scheme with full aggregation in VANET, using certificateless aggregate signature to achieve secure vehicle-to-infrastructure (V2I) communications. The technique of aggregate signature can achieve message authentication and greatly save the bandwidth and computation resources. In addition, we use pseudonym to realize conditional privacy preserving and a trace authority (TRA) is responsible for generating pseudonym and tracking the real identity during the communication if it is necessary. When a vehicle enters an area under a new road side unit (RSU)’s coverage, we pre-calculate some data for once, thus the computation cost in sign phase can be reduced. The length of aggregated signature is constant which reduces the communication and storage overhead.