| 摘要 |
PROBLEM TO BE SOLVED: To surely confirm that an electronic document is not altered for a long period of time. SOLUTION: Long storage data 102 for signature, long storage data 104 and 106 for timestamp are held in a long storage document. The long storage data 102 for signature is protected by signature data 103, and the long storage data 104 and 106 for timestamp is protected by a timestamp 105. In this case, processing of embedding the signature data 103 (timestamps 105 and 107) into the long storage document, following processing of embedding the long storage data 102 for signature (long storage data 104 and 106 for timestamp) into the long storage document. The long storage data 102 for signature (long storage data 104 and 106 for timestamp) and the signature data 103 (timestamps 105 and 107) are bound to each other. COPYRIGHT: (C)2008,JPO&INPIT |
