Patent ID: 7627754

Claim:
A document data identity verifying apparatus which verifies identity of document data, said apparatus comprising: an I/O unit which receives document data in a first format from a creation source of the document data and receives the document data in the first format or said document data which is converted in another format from a reception source of said document data; a format management unit which converts the document data in the first format received into another format according to a preset conversion definition; an irreversible cipher management unit which generates an irreversible cipher on the document data received; a file recorder which records a registrant ID, a document format, and the irreversible cipher associated with the document data; an irreversible cipher verification unit which verifies an irreversible cipher that is generated based on the document data in the first format received from said creation source or the document data converted into another format by said format management unit and an irreversible cipher that is generated based on document data received from a reception source; and an identity data recorder in which the irreversible cipher generated on the document data in the first format or the irreversible cipher generated on the document data that is converted into said another format by said format management unit and the irreversible cipher generated based on the document data from the reception source are associated with each other for storage, wherein a request from the reception source is judged whether the request is a file request or a verification request according to an identifier of the reception source, wherein identity of the document data received from said creation source and the document data received from said reception source is validated, and wherein said irreversible cipher verification unit, when results of said verification match with each other, searches said identity data recorder for document data converted into a format different from that of the document data received from the reception source, and transmits the document data searched out according to the request from the reception source.