A Personal Privacy-Ensured User Authentication Scheme

User authentication verifies the legitimacy of users and prevents service providers from offering services to unauthorized parties. The concept is widely applied in various scenarios, including everyday access control systems and IoT applications. With growing concerns about personal privacy, ensuring user anonymity has become increasingly important. In addition to privacy, user convenience is also a key factor influencing the willingness to adopt a system. To address these concerns, we propose a user authentication scheme that ensures personal privacy. The system consists of a backend server, multiple users, and multiple control units. Each user is issued or equipped with an authentication unit. An authorized user can be authenticated by a control unit, with assistance from the backend server, without revealing their identity to the control unit. The scheme is suitable for applications requiring privacy-preserving authentication. Furthermore, to enhance generality, the proposed design ensures computational efficiency and allows the authentication unit to adapt to specific application requirements.