| 摘要 |
PROBLEM TO BE SOLVED: To easily take a measure against impersonation by a third person by judging user terminal side authentication logic and authenticating a keyword by using the user terminal side authentication logic regarding a user authentication server connectable to a user terminal which transmits a user side conversion keyword converted according to the user terminal side authentication logic. SOLUTION: The user side authentication logic is judged by a user ID in an authentication logic judgment part 13. In a conversion keyword verification part 18, a keyword conversion part provided with server side authentication logic corresponding to the user side authentication logic is selected from a plurality of the keyword conversion parts 19-21, a server side conversion keyword is acquired and compared with the user side conversion keyword received in a user side conversion keyword reception part 17 and the keyword is verified. |
