Authentication device and authentication method

An authentication method executed by an authentication device that authenticates a user using person specifiable information, the authentication device including an electronic control unit that includes a storage unit configured to store person specifiable information for each of a plurality of registered users who are registered in advance and association information in which the plurality of registered users are associated with a predetermined terminal possessed by the plurality of registered users, the authentication method comprising:

• by the electronic control unit using the person specifiable information for the plurality of registered users and the association information stored in the storage unit,
• acquiring person specifiable information from an authentication target user;
• acquiring identification information that is transmitted from a terminal;
• specifying a user associated with the terminal transmitting the identification information based on the association information and the identification information;
• setting an order of the plurality of registered users based on the user specified;
• and
• authenticating the authentication target user by executing a comparison process between the person specifiable information of the authentication target user and the person specifiable information for the plurality of registered users stored in the storage unit in the order set.

A non-transitory storage medium for an authentication device that authenticates a user using person specifiable information, the authentication device including an electronic control unit that includes a storage unit configured to store person specifiable information for each of a plurality of registered users who are registered in advance and association information in which the plurality of registered users are associated with a predetermined terminal possessed by the plurality of registered users, the non-transitory storage medium including control logic executable by a computer processor so that the electronic control unit using the person specifiable information for the plurality of registered users and the association information stored in the storage unit:

• acquires person specifiable information from an authentication target user;
• acquires identification information that is transmitted from a terminal;
• specifies a user associated with the terminal transmitting the identification information based on the association information and the identification information;
• sets an order of the plurality of registered users based on the user specified;
• and
• authenticates the authentication target user by executing a comparison process between the person specifiable information of the authentication target user and the person specifiable information for the plurality of registered users stored in the storage unit in the order set.