Game Theory and Trust Management Driven Dynamic Proof-of-Work Blockchain Consensus Algorithm for Securing Internet of Vehicles

Recently, the dynamic Proof of Work (PoW) mechanism has attracted considerable attention as a promising consensus mechanism for implementing blockchain in the Internet of Vehicles (IoV) due to its superior scalability, security, and efficiency. However, existing protocols fail to address two critical issues, i.e., how to precisely quantify the relationship between dynamic difficulty and trust value and how to assess the motivation for mining in relation to mining costs. Addressing these issues is crucial for developing a secure, efficient, and adaptable dynamic PoW mechanism. To address these issues, we propose a trust management algorithm that assesses the trustworthiness of Roadside Units (RSUs) that function as consensus or mining nodes. Based on the results of this trust evaluation, a difficulty adjustment algorithm rooted in the Principal-Agent game theory was designed to implement a dynamic PoW mechanism for IoV. This approach leads to a Nash equilibrium between vehicles and RSUs, thereby ensuring the security, efficiency, and stability of the IoV blockchain system. Simulations demonstrated that the proposed dynamic PoW consensus algorithm significantly improves consensus efficiency, enhances system security, and reduces computational costs, offering a robust solution for data sharing in IoV.