Patent ID: 6907528

Claim:
A method for producing and authenticating a printed test certificate compressing the following steps: a) a test certificate producer performs a test and generates test information to be included in the test certificate; b) the test certificate producer generates said test information, and also pre-printed information read from a blank test certificate, to an authentication authority; c) the authentication authority checks whether the test certificate producer is authorized to perform the test and, if so, cryptographically generates an authentication code form said test information and said pre-printed information, and sends the authentication code back to the test certificate producer; d) upon receipt of the authentication code from the authentication authority, the test certificate producer prints both said test information and said authentication code on the blank test certificate; and e) upon presentation of the printed test certificate for authentication, a certificate checker cryptographically checks the authentication code against said test information and said pre-printed information in the printed test certificate to determine whether the printed test certificate is authentic.