An Efficient Post-Quantum Lattice-Based Encryption Scheme for Secure Communication in Vehicular Ad-Hoc Networks

Vehicular ad-hoc networks (VANET) are the key to advancing intelligent transportation and reducing traffic congestion. Nevertheless, the rapid increase in vehicle diversity introduces numerous challenges to maintaining secure and efficient vehicle communications. To address these challenges, we propose a new identity-based encryption scheme (IBES) based on lattice-based cryptography for secure communication in VANETs. Our scheme ensures timely message receipt, preserves the confidentiality of vehicle identity, and enables rapid authentication. Our scheme protects VANET devices against both active and passive attacks in their resource-constrained environment. The formal analysis verifies that adaptively chosen message attacks cannot break the encryption scheme using the random oracle model. The informal analysis shows that the scheme meets the security goals and is strong enough to protect against side-channel, man-in-the-middle (MITM), and replay attacks. Additionally, the SCYTHER tool is used for formal security validation, and the security analysis shows that the protocol is strong against chosen-plaintext attacks. We evaluate the effectiveness of the proposed scheme against existing approaches, focusing on the security attributes offered, computation, and communication cost. Our scheme shows lower storage overhead and higher authentication efficiency than similar existing schemes. Therefore, this combination establishes the proposed scheme as an efficient and practical solution for VANET.