Message authentication and conditional privacy preservation are two critical security issues in vehicular ad hoc networks (VANETs), which have been extensively studied in recent years. To achieve these security issues, many information security technologies have been proposed so far. Among them, pseudonyms-based and group-based messages signing and verifying are two of the main methods adopted in recently published literature. However, analysis points out that both of the two technologies have their downsides. To address these issues, a secure and efficient message authentication protocol (SEMA) is proposed in this article, which aims to achieve mutual authentication among vehicles and road-side units (RSUs) in VANETs by combining the advantages of pseudonyms-based and group-based methods. Security analysis shows that SEMA is robust to various security attacks. Performance evaluation demonstrates that SEMA is computationally lightweight on both vehicles and RSUs. Finally, simulations are performed to prove the feasibility in highway and urban environment.

中文翻译：

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SEMA：VANET的安全高效的消息身份验证协议

消息身份验证和有条件的隐私保护是车载自组织网络（VANET）中的两个关键安全问题，近年来已对其进行了广泛的研究。为了实现这些安全问题，迄今为止已经提出了许多信息安全技术。其中，基于假名和基于组的消息签名和验证是最近发表的文献中采用的两种主要方法。但是，分析指出，这两种技术都有其缺点。为了解决这些问题，本文提出了一种安全高效的消息身份验证协议（SEMA），旨在通过结合基于假名和分组的优点，在VANET中实现车辆和路边单元（RSU）之间的相互身份验证。基础的方法。安全分析表明，SEMA可以抵抗各种安全攻击。性能评估表明，SEMA在车辆和RSU上在计算上都是轻量级的。最后，进行了仿真，以证明在高速公路和城市环境中的可行性。