User authentication method and user authentication server

摘要: A user authentication method suitably for use in mobile information terminals, which minimizes load entering necessary while ensuring security is disclosed. Before using a service to be provided by client provider on the Internet, registers his personal including unique identification of terminal with provider. Then, when uses content server via terminal, sends encrypted information. The decrypts received and performs basis decrypted also checks charging surrogate registration user. If authenticated found registered, permits provide requested terminal.