An Enhanced Offline/Online Heterogeneous Signcryption Protocol With Batch Verification for Edge Computing-Based VANETs

Signcryption can efficiently ensure data confidentiality and authenticity simultaneously, which makes it ideal for use in secure communication of vehicular ad hoc networks (VANETs). Recently, Ali et al. constructed an efficient offline/online heterogeneous signcryption protocol for edge computing-based internet of vehicles (IEEE Trans. Intell. Transp. Syst., vol. 24, no. 12, pp. 14506-14519, Dec. 2023). In this paper, we demonstrate that their signcryption protocol lacks robustness against public key replacement attacks, and then introduce an enhanced signcryption protocol secure in the random oracles. Our certificate-based and identity-based heterogeneous signcryption protocol enables communication between entities in different cryptosystems, while ensuring pseudonym-based conditional privacy for vehicles. Additionally, it supports public verification for tracing malicious behavior from anonymous vehicles. Unlike other protocols, our protocol avoids costly pairings or map-to-point hashes, and incorporates online/offline construction and batch verification, significantly reducing communication delays and computational overhead. Performance analysis shows that our protocol outperforms existing approaches in VANETs.