Method for archiving documents with a digital signature on paper with a step for verifying the digital signature by scanning the document back in and checking the digital signature in conjunction with an encryption key

摘要

The electronic document is printed as a two- dimensional bitmap with data encoded using the secret key of the digital signature. The encoded data and the bitmap are printed in machine readable format and to verify the signature the printed form is scanned in and from the scanned two-dimensional bitmap image the digital signature is reconstructed so that the bitmap can be verified.