| 摘要 |
Authentication device 19 performs authentication using an element group image 43 which indicates an element group configured by arranging a plurality of elements. Authentication device 19 transmits screen data representing an authentication screen 41 to an accessing computer in order to display the authentication screen 41 on a display unit of the computer, the authentication screen 41 including the element group image 43, in which some or all of the plurality of elements change, a question 45 answerable by looking at the element group image 43 before a change and the element group image 43 after the change and an answer entry box 47. The question 45 is included in the authentication screen 41 with at least either before or after the change of the element group image 43. The answer entry box 47 is included in the authentication screen 41 after the change of the element group image 43. The authentication is succeeded if the answer entered in the answer entry box 47 is correct. |
