Patent ID: 8271391

Claim:
A method for securing an on-line transaction conducted by a client using a chipcard, said client being able to use a processing station, said processing station being able to communicate on line with an authentication authority, said processing station being equipped with a man/machine interface such as a screen, and a chipcard reader, the chipcard reader comprising a proximity test for verifying the physical presence of the client in the immediate vicinity of the processing station, an authentication test for the holder of the chipcard, and a transaction non-repudiation test, wherein the proximity test involves entry of information by the client which is determined to be equivalent to information sent to the client by the chipcard directly or via the chipcard reader, wherein the non-repudiation test comprises the following steps: storing commercial information relating to the on-line transaction in an image file in the authentication authority; transmitting the image file linked to the on-line transaction to the chipcard, via the processing station and the chipcard reader, wherein the image file from the chipcard is loaded in the processing station for display on the screen; decrypting an encrypted message received by the authentication authority; and validating the on-line transaction if verification is positive, wherein at least one item of financial information in the image file displayed on the screen is selected by the client, wherein corresponding coordinates of the financial information selected by the client are transmitted to the chipcard, and wherein a message comprising at least the financial information concerning the on-line transaction on the chipcard is encrypted to create the encrypted message and transmitted to the authentication authority.