Patent ID: 7711958

Claim:
A method for encoding authentication information in the filenames of computer files containing digital data, said method comprising: computing a hash value H 0 by applying a master hash function to only the digital data comprised by a master computer file, said master computer file having an original filename; computing a digital signature of the hash value H 0 using a private key of a sender such that the digital signature of H 0 has a predetermined fixed length; generating a signed filename of the master computer file by encoding the computed digital signature of the hash value H 0 in the original filename of the master computer file; associating the signed filename of the master computer file with the master computer file; computing a hash value H 1 by applying a first hash function to only the digital data comprised by a first computer file, said first computer file having an original filename; computing a digital signature of the hash value H 1 using the private key of the sender; generating a signed filename of the first computer file by encoding the computed digital signature of the hash value H 1 in the original filename of the first computer file; associating the signed filename of the first computer file with the first computer file; and generating a composite computer file by attaching to the master computer file the first computer file and its associated signed filename; and sending the composite computer file from the sender to a receiver.