Car Data Chain is a new ecological automotive service platform developed based on blockchain technology. It integrates blockchain technology into transaction scenarios, circulation scenarios, and service scenarios in the automotive industry, and stores automotive data from a series of information such as factory, sales, maintenance, and repair on the chain. Blockchain technology establishes a trust system based on machines rather than conventions. The decentralized system composed of technologies such as smart contracts and distributed databases makes the automotive service industry more transparent, authoritative, and fair. On the Car Data Chain platform, automobile manufacturers, sales points, automobile trading markets, automobile finance companies, automobile rental companies, insurance companies, and banks can all join the platform to form a comprehensive automobile service system and provide users with high-quality solutions....