LAAS-KM: Lightweight authentication with aggregate signature verification and key management protocol for VANETs

Abstract

Vehicular Ad Hoc Networks (VANETs) are a significant component of upcoming intelligent transportation systems. VANETs improve road safety by sending danger alerts to drivers; therefore, their messages must be secure and unaltered. Digital signatures are used to verify the integrity and authenticity of transmitted messages; however, existing digital signature-based schemes require a high computational time owing to the repeated use of mathematical operations. To address this issue, a novel signature aggregation and key management (LAAS-KM) scheme is proposed in this paper to reduce the computational cost without compromising security. First, the LAAS-KM allows roadside infrastructure to cluster multiple vehicle signatures into a compact signature to reduce the large computational overhead during the verification process. Moreover, LAAS-KM supports group communication with novel key management to update keys as vehicles move and network topologies change dynamically in VANETs. Moreover, the security analysis section indicates that the LAAS-KM can prevent various security attacks, including impersonation and replay attacks. Furthermore, a formal security analysis is performed using the Scyther tool to validate the critical security properties of LAAS-KM. Performance evaluations show that LAAS-KM outperforms traditional schemes in terms of communication and computation overheads. Finally, a practical simulation is performed using MATLAB, and the performance metrics are analyzed.