AUTHENTICATION SYSTEM AND AUTHENTICATION METHOD

PROBLEM TO BE SOLVED: To heighten strength of security of an authentication method having the low strength of the security when strength of the security of a plurality of authentication methods varies. SOLUTION: This authentication system has: an authentication information issuing part (S16) issuing authentication information according as it is authenticated by a biological authentication device; an authentication information storage part (S19) associating and storing the issued authentication information and user identification information of a user authenticated by the biological authentication device; an authentication information reception part (S23) receiving authentication information inputted by the user authenticated by a password authentication device; and a third authentication part (YES at S24) authenticating the user authenticated by the password authentication device on the condition that the received authentication information accords with the authentication information associated to the user identification information of the user authenticated by the password authentication device. COPYRIGHT: (C)2009,JPO&INPIT