Blockchain-Based Central Bank Digital Currencies: A Comprehensive Survey

In this information age, real currency is transitioning to digital currency. Blockchain technology has introduced smart contracts and distributed ledger technology, leading to new research directions in various fields including finance, the Internet of Things, and energy. Central Bank Digital Currency (CBDC) based on blockchain has been incorporated into the technical choices of central banks in various countries. This paper examines the current research and implementation of central bank digital currency by various central banks worldwide. It provides an overview of CBDC's definition, operational status, and technical characteristics. Additionally, this paper highlights the challenges and issues associated with CBDC systems in the current environment. These problems include security issues, performance issues, privacy protection issues, and legal issues. In this regard, some literature has proposed solutions, which are analyzed and summarized in this paper. We classify and summarize the existing problems and propose effective solutions, including using fragmentation technology to increase transaction throughput and implementing corresponding regulatory measures to strengthen supervision.