BCDAP-DGS: Dynamic Group Signature and Batch Cross-Domain Authentication Protocol for Intelligent Transportation

The Internet of Vehicles (IoV), as a core component of intelligent transportation systems, significantly enhances the intelligence level of traffic management by enabling efficient vehicle-to-vehicle (V2V) and vehicle-to-infrastructure information sharing. However, the highly dynamic and open nature of the IoV poses severe security challenges in cross-domain scenarios, mainly due to the lack of trust relationships between different domains, making it difficult to achieve efficient and secure cross-domain authentication(CDA). Existing CDA mechanisms in the IoT context often suffer from high computational complexity, excessive communication overhead, and poor scalability for large-scale deployments. This paper proposes a Batch CDA Protocol based on Dynamic Group Signatures (BCDAP-DGS) to address these issues. The proposed protocol incorporates non-interactive zero-knowledge (NIZK) proofs to achieve secure identity verification without requiring additional data exchange. By leveraging dynamic group signature techniques, BCDAP-DGS supports real-time updates of vehicle membership status and provides conditional anonymity. In addition, an online/offline authentication framework is designed by incorporating vehicle location information to precompute related parameters, thereby significantly improving CDA efficiency. A formal security analysis is conducted under the random oracle model, demonstrating that the proposed protocol satisfies essential security properties, including anonymity, non-frameability, unforgeability, and traceability. Experimental results and performance comparisons show that the proposed protocol outperforms existing schemes in terms of both security and efficiency, making it well-suited for large-scale and highly dynamic IoV CDA scenarios.