ELECTRONIC DOCUMENT MANAGEMENT SYSTEM WITH THE USE OF SIGNATURE TECHNIQUE CAPABLE OF MASKING

摘要

The present invention provides a technology for verifying the validity of an electronic document even if the electronic document is partially rendered private at the time of its disclosure by using a signature affixed to the electronic document at the time of its creation. A target electronic document is divided into two or more partial documents having an arbitrary or fixed length. This division is effected by using a tag in XML or another markup language so as to provide versatility or by adding a dedicated delimiter. The system has a signature function. The signature function uses a signature technique for generating the information for verifying the validity of each of the partial documents, and for validating a signature affixed to the electronic document to confirm the validity of the whole electronic document by affixing a signature to the aggregate of the generated validity confirmation information.