Authentication method, authentication system and authentication apparatus

An authentication system comprising:

• a portable information device;
• and
• an authentication apparatus,
• wherein the portable information device includes a display and a processor which executes processing comprising;
• acquisition processing for acquiring shared information that is sharable with the authentication apparatus when authentication of an electronic ticket stored in the portable information device is performed;
• generation processing for generating a bar code based on the shared information acquired in the acquisition processing and the electronic ticket;
• and
• display processing for displaying, on the display, the bar code generated in the generation processing, and
• wherein the authentication apparatus includes a bar code scanner and a processor which executes processing comprising;
• read processing for reading the electronic ticket and the shared information from the bar code displayed on the portable information device;
• and
• authentication processing for performing the authentication of the electronic ticket by making a comparison between contents of the shared information read together with the electronic ticket in the read processing and shared information in the authentication apparatus.

An authentication apparatus for authenticating an electronic ticket stored in a portable information device, comprising

• a bar code scanner;
• and
• a processor which executes processing comprising:
• read processing for reading the electronic ticket and shared information from a bar code displayed on the portable information device;
• and
• authentication processing for performing authentication of the electronic ticket by making a comparison between contents of the shared information read together with the electronic ticket in the read processing and shared information in the authentication apparatus.