# A Blockchain Solution for the Internet of Vehicles with Better Filtering and Adaptive Capabilities
## 1 Introduction  
The development of automobiles has gone through several stages, from steam-powered vehicles to modern electric and self-driving cars; automobile intelligence has become an important innovation direction [1, 2, 3], attracting widespread attention. Smart cars employ advanced information technology, artificial intelligence, and sensor technology, providing a safer, more convenient, and comfortable travel experience. The earliest automobile intelligence concentrated on the car, such as through intelligent driving assistance, in-car entertainment systems, and voice control to improve safety, comfort, and convenience [4, 5]. These technologies perform data processing inside the vehicle. With new communication technologies, such as fifth-generation (5G) [6] and the forthcoming sixth-generation (6G) mobile communication [7], vehicles have begun to connect with external entities, bringing unprecedented opportunities and challenges to the automotive industry. Vehicular Networking [8] is an important component of the intelligent transportation system. It provides a trusted platform connecting vehicles, road infrastructure, and cloud services. Vehicles in the network can interact and integrate valuable information in real time, improving the vehicle's capabilities in control execution [9], decision-making [10], and environmental perception [11]. However, due to the high speed of vehicles and thedynamic topology of the system caused by sudden interactions, collaboration between vehicles faces security and privacy challenges. Identity authentication is a critical mechanism for enhancing the robustness of IoV systems and ensuring stable operation [12]. During regular operation, IoV systems may be subject to malicious attacks, such as compromised vehicles intentionally transmitting false information about road conditions to other vehicles, or tampered data at compromised base stations, which can severely compromise the security and reliability of the system. Traditional password-based identity authentication methods, primarily relying on encryption mechanisms like public key infrastructure (PKI), suffer from poor scalability and adaptability. Compared with traditional password authentication, trust management [13] is more flexible, secure, and efficient, and is more suitable for the complex, changeable scenarios of the vehicular network. It can calculate the credibility of messages, and allocate, calculate, and update the reputation values of vehicles, which are generally stored in a central cloud server or roadside unit (RSU). However, the servers storing data are vulnerable to attack [14; 15], which may result in the inability to provide reliable and consistent trust services for the entire vehicle network, and can affect the safety of property and passengers. Blockchain technology is considered a good solution for the above problems. This distributed ledger technology was proposed by [PERSON] in 2008 and first implemented with Bitcoin in 2009 [16]. It is based on cryptography and distributed computing, enabling distributed nodes to trade with each other and maintain consistent and tamper-proof ledgers without the supervision of a centralized institution. It links transaction records in blocks in chronological order and uses cryptographic algorithms to ensure they are tamper-proof and secure. Due to its privacy and security characteristics, blockchain has been widely studied and has been applied in non-financial scenarios, such as decentralized storage [17], content delivery [18], and key management [19]. Leveraging the decentralized, tamper-proof, and transparent characteristics of blockchain technology and integrating it with IoV can establish a decentralized and authorized system using the Byzantine consensus algorithm. This integration addresses critical challenges related to data sharing and security. Although blockchain technology has demonstrated significant potential in enhancing security, privacy, and trust in vehicular networks, it still faces inherent limitations.