Vehicular ad hoc network (VANET) has been a promising technology in smart transportation system, which can enable information exchange between vehicles and roadside units (RSUs). However, the privacy of vehicles and RSUs is a critical challenge in VANET, as they may expose sensitive information to malicious attackers or unauthorized parties. Many existing authenticated key agreement (AKA) schemes aim to protect the privacy of vehicles and RSUs, but they often neglect the physical security of the devices involved in the communication. Therefore, we propose an efficient and privacy-preserving AKA scheme in VANET, which embeds physical unclonable function (PUF) and fuzzy extraction (FE) technology. PUF is a physical device that generates random strings based on their intrinsic characteristics and external inputs, which can protect the secrets in the devices from being stolen by attackers. FE can compensate for the drawbacks of PUF affected by environmental factors. Our scheme preserves the identity privacy of legitimate RSUs and vehicles, as well as intercepts and traces the identity of malicious attackers. In addition, we eliminate the involvement of the third party (TP) in the AKA phase to better meet the high-speed driving of vehicles. Finally, we conduct formal and informal security analyses in random oracle model (ROM), which prove that our scheme can resist various attacks. We also show in the performance analysis that our scheme has the lowest computational cost, communication overhead, and total energy consumption.

中文翻译：

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EPAKA：一种基于 VANET 物理安全性的高效且保护隐私的身份验证密钥协议方案


车载自组网 （VANET） 一直是智能交通系统中一项很有前途的技术，它可以实现车辆和路边单元 （RSU） 之间的信息交换。然而，车辆和 RSU 的隐私是 VANET 的一个关键挑战，因为它们可能会将敏感信息暴露给恶意攻击者或未经授权的各方。许多现有的经过身份验证的密钥协议 （AKA） 方案旨在保护车辆和 RSU 的隐私，但它们往往忽视了通信中涉及的设备的物理安全性。因此，我们在 VANET 中提出了一种高效且隐私保护的 AKA 方案，该方案嵌入了物理不可克隆函数 （PUF） 和模糊提取 （FE） 技术。PUF 是一种物理设备，它根据自身的内在特性和外部输入生成随机字符串，可以保护设备中的机密不被攻击者窃取。FE 可以补偿 PUF 受环境因素影响的缺点。我们的方案保留了合法 RSU 和车辆的身份隐私，并拦截和追踪恶意攻击者的身份。此外，我们消除了第三方 （TP） 在 AKA 阶段的参与，以更好地满足车辆的高速驾驶。最后，我们在随机预言机模型 （ROM） 中进行了正式和非正式的安全分析，证明我们的方案可以抵御各种攻击。我们还在性能分析中表明，我们的方案具有最低的计算成本、通信开销和总能耗。