Patent ID: 8290875

Claim:
An authentication method, comprising: dividing a credit card number into a first portion and a second portion different from the first portion, the credit card number being completely reconstructable from the first portion and the second portion; transmitting (1) the first portion of the credit card number from a portable telephone device ( 10 ) of a user to an ID issuance server ( 20 ); transmitting (2) a one-time ID corresponding to the first portion of the credit card number from the ID issuance server ( 20 ) to the portable telephone device ( 10 ); transmitting (3) the first portion of the credit card number and the one-time ID from the ID issuance server ( 20 ) to a number construction and authentication processing server ( 40 ); transmitting (4) the second portion of the credit card number, the one-time ID and user purchase data from a computer ( 11 ) of the user to a service provision server ( 30 ) via the internet; forming settlement data at the service provision server ( 30 ) from the purchase data; transmitting (5) the second portion of the credit card number, the one-time ID and the settlement data from the service provision server ( 30 ) to the number construction and authentication processing server ( 40 ); ensuring at the number construction and authentication processing server ( 40 ) that the one-time ID received with the second portion of the credit card number matches the one-time ID received with the first portion of the credit card number; reconstructing the full credit card number at the number construction and authentication processing server ( 40 ) from the first and second portions of the credit card number; forming a settlement checking result at the number construction and authentication processing server ( 40 ) from the full credit card number and the settlement data; transmitting (6) the settlement checking result from the number construction and authentication processing server ( 40 ) to the service provision server ( 30 ); forming an order result at the service provision server ( 30 ) from the settlement checking result; and transmitting (7) the order result from the service provision server ( 30 ) to the computer ( 11 ) of the user via the internet.