Cooperative perception is crucial for connected automated vehicles in intelligent transportation systems (ITSs); however, ensuring the authenticity of perception data remains a challenge as the vehicles cannot verify events that they do not witness independently. Various studies have been conducted on establishing the authenticity of data, such as trust-based statistical methods and plausibility-based methods. However, these methods are limited as they require prior knowledge such as previous sender behaviors or predefined rules to evaluate the authenticity. To overcome this limitation, this study proposes a novel approach called zero-knowledge Proof of Traffic (zk-PoT), which involves generating cryptographic proofs to the traffic observations. Multiple independent proofs regarding the same vehicle can be deterministically cross-verified by any receivers without relying on ground truth, probabilistic, or plausibility evaluations. Additionally, no private information is compromised during the entire procedure. A full on-board unit software stack that reflects the behavior of zk-PoT is implemented within a specifically designed simulator called Flowsim. A comprehensive experimental analysis is then conducted using synthesized city-scale simulations, which demonstrates that zk-PoT's cross-verification ratio ranges between 80 % to 96 %, and 80 % of the verification is achieved in 2 s, with a protocol overhead of approximately 25 %. Furthermore, the analyses of various attacks indicate that most of the attacks could be prevented, and some, such as collusion attacks, can be mitigated. The proposed approach can be incorporated into existing works, including the European Telecommunications Standards Institute (ETSI) and the International Organization for Standardization (ISO) ITS standards, without disrupting the backward compatibility.

翻译：协同感知对于智能交通系统（ITS）中的网联自动驾驶车辆至关重要，然而确保感知数据的真实性仍是一项挑战——因为车辆无法独立验证其未直接目击的事件。现有研究主要通过基于信任的统计方法和基于合理性的方法验证数据真实性，但这些方法存在局限性，需要依赖先验知识（如发送方历史行为或预定义规则）进行真实性评估。为突破这一限制，本文提出一种名为零知识交通证明（zk-PoT）的新方法，通过生成交通观测数据的密码学证明来实现验证。任何接收方均可对同一车辆产生的多个独立证明进行确定性交叉验证，而无需依赖地面实况、概率或合理性评估。同时，整个流程不会泄露任何隐私信息。我们在自主设计的仿真器Flowsim中实现了反映zk-PoT行为的完整车载单元软件栈，并基于合成城市场景仿真开展了全面实验分析。结果表明：zk-PoT的交叉验证比率可达80%至96%，80%的验证过程在2秒内完成，协议开销约为25%。此外，针对多种攻击的分析显示，该方法可防范绝大多数攻击场景，并能缓解共谋攻击等特定威胁。本方案可无缝集成至现有体系（包括欧洲电信标准协会与国际标准化组织的ITS标准），且不破坏后向兼容性。