Authentication system, authentication method and service providing system

An authentication method comprising:

• producing, by an authentication terminal, an artifact authentication result;
• and
• authenticating, by an authentication server, an authentication subject based on the artifact authentication result, wherein
• the producing the artifact authentication result includes:
• authenticating, using an authentication apparatus on the authentication terminal, the authentication subject using inherent information of the authentication subject;
• receiving, at a signal processing section included in the authentication terminal, a subject authentication result, from the authentication apparatus, indicating whether the authentication subject is authenticated;
• receiving, at the signal processing section, designation information from the authentication server;
• inputting, by the signal processing section to an artifact on the authentication terminal only if the authentication subject is authenticated by the authentication apparatus, as an input signal, a signal based on the designation information from the authentication server, the input signal not including the inherent information of the authentication subject;
• performing, at the artifact, an operation in accordance with the input signal and outputting, from the artifact, a result of the operation as an operation result;
• and
• outputting, from the signal processing section to the authentication server, as the artifact authentication result, an output signal in accordance with the operation result of the artifact, and
• the authenticating the authentication subject based on the artifact authentication result includes:
• storing information indicating an input/output characteristic of the artifact;
• and
• authenticating the authentication subject based on whether the artifact authentication result indicates that the input signal resulted in the output signal in accordance with the input/output characteristic of the artifact;
• wherein the producing the artifact authentication result further includes:
• storing a plurality of input signals in association with a plurality of addresses;
• determining a base address with the authentication server;
• and
• inputting the input signal, from the signal processing section to the artifact, at an address shifted from the base address by an address offset designated by the authentication server.