Unified Identity Authentication System Based on Blockchain

In traditional centralized application construction and data storage modes, the application servers and the users are not in equal position in user information management. The application server can store and abuse the user's information under the circumstances that the users are not aware, and the user cannot revoke the authorization from the application server. Therefore, this paper proposes an identity management system combined with blockchain technology, which can return the management right of user information to users. This system adopts a three-layer architecture composed of blockchain layer, virtual chain layer and storage layer, and encapsulates all functions in each layer. It has good flexibility, and is easy to add new technologies, with good extensibility. The blockchain records the user's information state to realize the consensus and integrity of the user's data. The virtual chain layer is responsible for the main logical functions and encapsulates the user's request into a blockchain transaction, maintaining a good portability. The storage layer is responsible for the actual file storage and is responsible for file routing, backup, and query. Comprehensively speaking, based on the above three layers' architecture, the system implements the user's privacy granularity control, the user file's external storage, and combines the zero-knowledge proof to update the user's private key. In view of the application environment of this system, the access time delay and efficiency of the P2P storage system are simulated. It solves the problems of centralized application construction and data storage mode under which users cannot fully control personal information and privacy protection.