Edge-Assisted Hierarchical Batch Authentication Scheme for VANETs

With the development of novel information technologies and transportation systems, vehicular ad hoc networks (VANETs) have become an important means to improve drivers' experience and reduce road accidents. There are still some challenges regarding vehicle privacy information security and information transmission efficiency in VANETs. To address these challenges, edge nodes are utilized to verify signatures in some existing work, which can reduce the computational overhead of the trusted authority (TA) and improve the efficiency of authentication schemes. Although authentication efficiency has been improved, these schemes also bring potential security risks. Edge nodes located in outdoor environments are vulnerable to attacks, which may result in problems with verification. The TA may verify security parameters twice, such as identities or signatures, resulting in a redundant authentication problem. An authentication scheme assisted by edge nodes is proposed in this article as a solution to this problem. Road-side units (RSUs) serve as edge nodes to verify messages from vehicles and generate lists of valid and invalid messages via a batch detection algorithm, to assist the TA in checking authentication results. Furthermore, the TA can get a correct and valid message list only by a batch check of RSUs results. The proposed scheme also provides an efficient solution to the problem of authentication. In addition, by delegating most authentication tasks to RSUs, the overall efficiency of the scheme is improved. For example, when 100 messages are generated, the batch authentication overhead and transmission overhead of the proposed scheme are approximately 98% and 61% of the ECC-based scheme proposed in the literature. The security analysis and experimental analysis demonstrate that the proposed scheme meets the security requirements of VANETs and has a smaller computational overhead and communication cost than previous work.