Message Authentication Mechanism and Privacy Protection in the Context of Vehicular Ad Hoc Networks

Vehicular ad hoc networks (VANETs) have been widely researched in recent years. VANETs are used mostly for road safety and traffic efficiency; therefore, it is imperative that the communication between vehicles is rapid and secure in a VANET environment. In the present study, bilinear pairings were used to construct a complete message authentication scheme. This scheme provided the following features: (1) vehicle or roadside unit (RSU) parameters were determined via a hierarchical protocol, which prevented potentially a large computational overhead for a single node; (2) message broadcasts and private communications between vehicles in the transmission range of the same RSU were enabled; (3) message broadcasts and private communications between vehicles in the transmission ranges of different RSUs were enabled; (4) a fast handoff mechanism was established for vehicles in the transmission ranges of different RSUs; and (5) mechanisms for message broadcasts and private communication were established for vehicles in areas where RSUs were sparsely located. Based on the experimental results, our scheme was confirmed to be superior to previous schemes. In terms of security, our scheme offered the following features: confidentiality, message integrity, nonrepudiation, conditional anonymity, and conditional untraceability.