A Method of An Anonymous Authentication For Flat-rate Service

As the ubiquitous society spreads rapidly, various private information circulates in large quantities. Information increases explosively in recent years, the importance of privacy protection has risen. When the Web services are used, they need not identify who is the user in some cases. In this paper, we propose the authentication method that achieves privacy protection with authorization without identification. Our method makes it possible to protect user’s privacy information when the services. We discuss the security of the attacks, and the untraceability from attribute information to identity information. Thereby we show the effectiveness of our method.