Patent ID: 7035831

Claim:
A reversible generation process of altered payment cards by a mathematical algorithm, for Ecommerce transactions carried out over the Internet, and using cards furnished with a determined payment card number, comprising a BIN in the first positions, intermediary positions and a final digit referred to as the “Check Digit” and data corresponding to the expiry date, once the customer has decided on the real payment card, wherein: An Authentication Server of an issuer generates a transaction signature with prior authentication by a payment cardholder; The Authentication Server of the issuer carries out the decimalisation of the transaction signature to obtain a valid permutation number according to the number of positions to be permuted on the payment card number; The payment card's intermediary digits are permuted by fixing of a BIN by a processor and maintaining the Check Digit of the payment card and at the same time by changing the payment card's expiry date, which is used as the altered card's expiry date; The altered card is sent in the data flow of the transaction of the means of payment to carry out the corresponding authorisation request in a processing centre of the issuer instead of with the original, through an acquiring server; The processing centre of the issuer generates the transaction signature by the same process as the authentication server in the first step; the decimalisation of the transaction signature is calculated in the same way as in the second step; the expiry date of the real card is obtained by the inverse process of changing the altered card's expiry date to put each digit of the altered payment card number back in the initial positions on the original card carrying out the inverse permutation process ( 15 ) of the process carried out in the third step to put each digit of the altered payment card number back in the initial positions on the original card; the processing centre of the issuer generates the altered number when necessary in the lifecycle of the transaction.