AUTHENTICATION METHOD, AUTHENTICATION DEVICE, PROGRAM, AND RECORDING MEDIUM

An authentication method and the like which is able to flexibly perform authentication for an information processing devices having different security levels in accordance with transaction conditions at a high security level. A Web server (1) receives information related to biometric authentication concerning a computer (2), receives information related to identification information for identifying the computer (2) and receives information related to environment of the computer (2). The Web server (1) also receives an electronic signature transmitted from the computer (2). A level determining means determines a biometric level based on the received information related to biometric authentication, machine level based on the information related to identification information and an environment level based on the information related to environment. A correcting means corrects the determined level based on validity of the electronic signature by a secret key which is paired with the user's electronic certification. When the level determined by all of the corrected biometric level, machine level and environment level is equal to or more than a reference level stored in advance, the judging means judges the device as positive.