Open Access

ARTICLE

A Lightweight Quantum-Secure Authentication and Key Agreement Protocol for Vehicular Ad-Hoc Networks

Lasseni Coulibaly^1,*, Damien Hanyurwimfura¹, Evariste Twahirwa¹, Abubakar Diwani²

1 African Center of Excellence in Internet of Things (ACEIoT), University of Rwanda, Kigali, Rwanda
2 Department of Computer Science and IT, The State University of Zanzibar, Zanzibar, Tanzania

* Corresponding Author: Lasseni Coulibaly. Email:

Computers, Materials & Continua 2026, 89(2), 41 https://doi.org/10.32604/cmc.2026.087148

Received 12 June 2026; Accepted 21 July 2026; Issue published 15 September 2026

Abstract

Intelligent transportation systems, a critical pillar for smart cities, enable real-time vehicular communications to prevent human errors and improve traffic safety and efficiency. However, the open and highly dynamic nature of vehicular networks exposes them to various security threats, including message tampering, impersonation, and privacy violations. Several authentication and key agreement (AKA) protocols have been proposed to mitigate these risks, but often fail to maintain future-proof security against emerging quantum threats or introduce significant latency that affects real-time applications by relying on computationally expensive public-key cryptography, blockchain or centralized architectures. This paper proposes a new AKA protocol that combines hash-based operations with the Blom’s key pre-distribution scheme and the standardized Module-Lattice-Based Key Encapsulation Mechanism (ML-KEM) to achieve lightweight and quantum-secure mutual vehicular authentications in a decentralized architecture. Formal security verifications together with informal security analysis demonstrate resistance against common network attacks, while performance evaluations confirm reduced computational costs up to 99.95% and communication overhead reductions from 8.46% to 87.08% compared with related methods. Moreover, NS-3 simulations under varying densities and mobility conditions demonstrate high packet delivery reliability, low end-to-end authentication latency, and excellent scalability, making the proposed protocol a practical solution for next-generation quantum-secure vehicular networks.

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Keywords

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