EPP-GAS: An Efficient and Privacy-Preserving Cross Trust-Domain Group Authentication Scheme for Vehicle Platoon Based on Blockchain

The vehicle platooning (VP) going across different regions together, plays an important role in improving traffic efficiency. Then how to perform authentication efficiently for the vehicle platoons becomes the basic requirements in the Internet of Vehicles, especially cross different trust domains. In this paper, we propose an efficient and privacy-preserving cross trust-domain group authentication scheme for VP based on blockchain, named EPP-GAS. We design an extended blockchain model, which encodes the VP authentication parameters into the BM-Tree block, to support the sharing of VP authentication parameters cross multiple trust-domains. Then, we construct group pseudonym based on Shamir’s threshold scheme, to realize anonymous group authentication efficiently. Also, we propose a group authentication scheme with batch identity authentication through dynamic adaption of VP adjustment and efficient re-authentication in the case of authentication failure. Compared with the existing authentication schemes, our scheme has better performance in terms of security, authentication efficiency, communication overhead, and increase efficiency for cross trust-domain group authentication by 31% on average and reduce the communication overhead by 43.9% on average.