Patent ID: 7900050
Filing Date: 2011-03-01
Classification: G06F,G06Q,H04L

Abstract:
1. A non-transitory computer readable medium storing a digital document management program that allows a computer to manage document information created and registered in a digital form, the program causing the computer to execute a process comprising: dividing the document information into a plurality of parts and generating partial identification information that represents the respective parts of the document information using a hash function for the respective parts of the document information; substituting a part of the document information to be undisclosed with the partial identification information of the part of the document information to be undisclosed at a correction time of the document information; creating a digital signature to be appended to the document information using the partial identification information; managing the document information; and verifying the validity of the managed document information, wherein at the registration time of new document information, the managing manages a digital signature created by the creating in association with the document information and, at the correction time of the document information, the managing acquires partial identification information related to a substituted part of the document information before substitution, allows the creating to create a digital signature to be appended to the substituted document information, and manages the digital signature and partial identification information related to the substituted part of the document information before substitution in association with the substituted document information, and the verifying uses the partial identification information and digital signature managed in association with the substituted document information by the managing and partial identification information newly created from the substituted document information by the dividing to perform the verification.