车联网(IoV)在通过连接人们来推进智能交通方面至关重要,车辆,基础设施,和云服务器(CS)。然而,IoV内的开放接入无线信道容易受到恶意攻击。因此,认证密钥协商协议对于确保车辆通信安全和保护车辆隐私至关重要。然而,尽管小组中的车辆遭到破坏,它们仍然可以更新组密钥并获得现有组密钥协商协议中的通信内容。因此,保证妥协后的前向安全性(PCFS)仍然具有挑战性。动态密钥轮换是实现PCFS的常用方法,这带来了沉重的计算和通信负担。为了解决这些问题,为IoV设计了一种高效、鲁棒的PCFS连续组密钥协商(ER-CGKA)方案。提出和提交流程用于支持异步组密钥更新。此外,基于TreeKEM架构,计算成本和通信开销显著降低。此外,我们采用阈值机制来抵抗恶意车辆的串通攻击,这增强了ER-CGKA方案的鲁棒性。安全性分析表明,该方案满足IoV的所有基本安全要求,并实现了PCFS。性能评估结果表明,我们的ER-CGKA方案的计算成本降低了18.82%(客户端)和33.18%(CS),由于假名被用来实现有条件的隐私保护,通信开销增加了约55.57%。因此,我们的ER-CGKA方案是安全和实用的。
The Internet of Vehicles (IoV) counts for much in advancing intelligent transportation by connecting people, vehicles, infrastructures, and cloud servers (CS). However, the open-access wireless channels within the IoV are susceptible to malicious attacks. Therefore, an authentication key agreement protocol becomes essential to ensure secure vehicular communications and protect vehicle privacy. Nevertheless, although the vehicles in the group are compromised, they can still update the group key and obtain the communication content in the existing group key agreement protocols. Therefore, it is still challenging to guarantee post-compromise forward security (PCFS). Dynamic key rotation is a common approach to realizing PCFS, which brings a heavy computation and communication burden. To address these issues, an efficient and robust continuous group key agreement (ER-CGKA) scheme with PCFS is designed for IoV. The propose-and-commit flow is employed to support asynchronous group key updates. Besides, the computation cost and communication overhead are significantly reduced based on the TreeKEM architecture. Furthermore, we adopt the threshold mechanism to resist the collusion attacks of malicious vehicles, which enhances the ER-CGKA scheme\'s robustness. Security analysis indicates that the proposed scheme satisfies all the fundamental security requirements of the IoV and achieves PCFS. The performance evaluation results show that our ER-CGKA scheme demonstrates a reduction in the computation cost of 18.82% (Client) and 33.18% (CS) approximately, and an increase in communication overhead of around 55.57% since pseudonyms are utilized to achieve conditional privacy-preserving. Therefore, our ER-CGKA scheme is secure and practical.