Pairing-Free Certificateless Aggregate Signcryption Scheme for Vehicular Sensor Networks

Smart vehicle applications play an increasingly significant role in constructing intelligent transportation systems. Vehicles with sensors are able to form temporary vehicular sensor networks dynamically, in which a mass of data are collected, shared, and aggregated to the traffic administration for improving road safety and efficiency. In such networks, vehicles exchange urgent or sensitive information with others in open wireless channels. To ensure secure and privacy-preserving communications, we develop a new pairing-free certificateless aggregate signcryption scheme based on the elliptic curve cryptosystem. The certificateless setting prevents the proposed scheme from both certificate management and key escrow issues. Aggregate signcryption without pairings realizes the aggregation and simultaneous authentication of multisource data by efficient cryptographic computing. The proposed scheme is proved to achieve confidentiality and unforgeability with the random oracle model. The security analysis shows that the proposed scheme provides forward secrecy, immunity to various known attacks, and pseudonym-based conditional privacy for vehicles. The performance analysis demonstrates that it satisfies more security properties with higher computation efficiency and lower communication overhead than state-of-the-art schemes.