A Lightweight Certificateless Cross-domain Authentication Scheme for 6G-Based Internet of Vehicles (IoVs)

6G wireless communication technology is set to provide the Internet of Vehicles (IoVs) with increased data transmission rates and reduced latency. Specifically, the high device density and end-to-end communication capabilities of 6G networks will enable vehicles to exchange information more effectively with other vehicles and road infrastructure, which is of significant importance for enhancing traffic efficiency and reducing accidents. Given the openness of the IoVs and the high dynamism of vehicular nodes, the realization of secure cross-regional vehicular travel has become a widely concerned issue. Researchers globally have integrated blockchain technology into the IoVs, proposing a series of cross-domain authentication schemes. However, these schemes still face challenges such as substantial certificate management pressure and communication delays. In response to these issues, we propose a cross-domain batch authentication scheme under the 6G network environment, which alleviates storage pressure by employing certificateless public key cryptography and does not involve third-party entities such as Certificate Authorities (CA) or Public Key Infrastructures (PKI). Additionally, our scheme utilizes Elliptic Curve Cryptography (ECC) to reduce the computational overhead of the scheme. The shorter key lengths in ECC imply that, at the same level of security, ECC algorithms offer faster computation speeds and require less processing power and storage space. Experiments have demonstrated that our proposed scheme significantly enhances the authentication efficiency of messages across trust domains, reducing computational overhead by more than 22.1%in the authentication of a large volume of cross-domain messages compared to other schemes.