In recent years, Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communication brings more and more attention from industry (e.g., Google and Uber) and government (e.g., United States Department of Transportation). These Vehicle-to-Everything (V2X) technologies are widely adopted in future autonomous vehicles. However, security issues have not been fully addressed in V2V and V2I systems, especially in key distribution and key management. The physical layer key generation, which exploits wireless channel reciprocity and randomness to generate secure keys, provides a feasible solution for secure V2V/V2I communication. It is lightweight, flexible, and dynamic. In this paper, the physical layer key generation is brought to the V2I and V2V scenarios. A LoRa-based physical key generation scheme is designed for securing V2V/V2I communications. The communication is based on Long Range (LoRa) protocol, which is able to measure Received Signal Strength Indicator (RSSI) in long-distance as consensus information to generate secure keys. The multi-bit quantization algorithm, with an improved Cascade key agreement protocol, generates secure binary bit keys. The proposed schemes improved the key generation rate, as well as to avoid information leakage during transmission. The proposed physical layer key generation scheme was implemented in a V2V/V2I network system prototype. The extensive experiments in V2I and V2V environments evaluate the efficiency of the proposed key generation scheme. The experiments in real outdoor environments have been conducted. Its key generation rate could exceed 10 bit/s on our V2V/V2I network system prototype and achieve 20 bit/s in some of our experiments. For binary key sequences, all of them pass the suite of statistical tests from National Institute of Standards and Technology (NIST).

中文翻译：

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基于LoRa的物理层密钥生成，用于安全的V2V / V2I通信。

近年来，车对车（V2V）和车对基础设施（V2I）通信引起了业界（例如Google和Uber）和政府（例如美国运输部）的越来越多的关注。这些车辆对一切（V2X）技术已在未来的自动驾驶汽车中广泛采用。但是，在V2V和V2I系统中，尤其是在密钥分发和密钥管理中，安全性问题尚未得到完全解决。利用无线信道互易性和随机性生成安全密钥的物理层密钥生成为安全的V2V / V2I通信提供了可行的解决方案。它轻巧，灵活且动态。本文将物理层密钥生成带到了V2I和V2V方案中。基于LoRa的物理密钥生成方案旨在保护V2V / V2I通信的安全。该通信基于远程（LoRa）协议，该协议能够在长距离内测量接收信号强度指示器（RSSI）作为共识信息以生成安全密钥。具有改进的级联密钥协商协议的多位量化算法可生成安全的二进制位密钥。所提出的方案提高了密钥生成速率，并避免了传输过程中的信息泄漏。在V2V / V2I网络系统原型中实现了所提出的物理层密钥生成方案。在V2I和V2V环境中的大量实验评估了所提出的密钥生成方案的效率。已经在真实的户外环境中进行了实验。在我们的V2V / V2I网络系统原型上，其密钥生成速率可能会超过10位/秒，在我们的某些实验中达到20位/秒。对于二进制密钥序列，它们都通过了美国国家标准技术研究院（NIST）的统计测试套件。