The vehicular ad hoc network (VANET) is a basic component of intelligent transportation systems. Due to the growing security and privacy-preserving requirements of the VANET, a lot of conditional privacy-preserving authentication (CPPA) protocols have been proposed in recent years. Unfortunately, the traditional CPPA protocols, which are based on a trusted authority (TA) and rely solely on classical mathematical problems, cannot resist quantum attacks. Moreover, these protocols do not take into account the increasingly complex traffic flow in the VANET and cannot utilize fog nodes (FNs) to assist in the TA’s authentication work. In this paper, we design a lattice-based and fog-assisted conditional privacy-preserving authentication (LFCPPA) protocol to solve the above challenges. Compared to existing solutions, we have made the following improvements. First, our protocol is resistant to quantum attacks. Second, the solution supports batch processing of signature verification and mutual authentication of identity between the TA / FNs and vehicles. Third, in our design, FNs reduce the computing pressure of the TA to improve the efficiency of the system. In addition, we demonstrate the security of the protocol under the random oracle model with provable security. Finally, the efficiency and security of this scheme are better than similar solutions. Specifically, compared with the latest scheme, in terms of computational cost, our scheme is reduced by 74.47%, 85.58%, 19.69%, and 85.90% in the four stages of the protocol. Meanwhile, in terms of communication cost, our protocol reduces it by 89.98%.

中文翻译：

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基于格子的条件隐私保留批量认证协议，用于雾辅助车辆自组网


车辆自组网 （VANET） 是智能交通系统的基本组成部分。由于 VANET 的安全性和隐私保护要求不断增长，近年来提出了许多有条件的隐私保护身份验证 （CPPA） 协议。遗憾的是，传统的 CPPA 协议基于可信权威 （TA） 并仅依赖于经典数学问题，无法抵御量子攻击。此外，这些协议没有考虑到 VANET 中日益复杂的流量，无法利用雾节点 （FN） 来协助 TA 的身份验证工作。在本文中，我们设计了一种基于晶格和雾辅助的条件隐私保护身份验证 （LFCPPA） 协议来解决上述挑战。与现有解决方案相比，我们进行了以下改进。首先，我们的协议可以抵抗量子攻击。其次，该解决方案支持 TA / FN 与车辆之间签名验证和身份相互认证的批处理。第三，在我们的设计中，FN 减轻了 TA 的计算压力，从而提高了系统的效率。此外，我们还演示了随机预言机模型下协议的安全性，并具有可证明的安全性。最后，该方案的效率和安全性优于同类方案。具体来说，与最新的方案相比，在计算成本方面，我们的方案在协议的四个阶段分别降低了 74.47%、85.58%、19.69% 和 85.90%。同时，在通信成本方面，我们的协议降低了 89.98%。