Digital document management system, digital document management method, and digital document management program

• US 8,091,015 B2
• Filed: 10/18/2006
• Issued: 01/03/2012
• Est. Priority Date: 07/20/2004
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Yoshioka, Takashi, Takenaka, Masahiko
• Primary Examiner(s): Hong, Stephen
• Assistant Examiner(s): ROBINSON, MARSHON L
• Application Number:
  US11/585,299
• Publication Number:
  US 20070050713A1
• Time in Patent Office: 1,903 Days
• Field of Search: 715/201, 715/716, 715/723, 715/203, 715/229, 715/249
• US Class Current: 715/201
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures
• CPC Class Codes: G06F 40/166 Editing, e.g. inserting or deleting
• CPC Class Codes: G06F 40/197 Version control for software G06F8/71
• CPC Class Codes: G06Q 10/10 Office automation; Time management

Abstract

A digital document management system is capable of guaranteeing that a partial correction has been made according to a proper procedure and achieving a third-party certification of the validity of the guarantee. The digital document management system manages document information created in a digital form, and includes partial identification information generation section that generates partial identification information that represents, in an identifiable manner, respective parts of the document information. A partial correction information generation section generates partial correction information which is information related to a correction history of a corrected part in the case where any correction has been required for the document information; and an original document information management section manages the document information, partial identification information, partial correction information, and prescribed policy information in an associated manner.

Claims

1. A digital document management system that manages document information created in a digital form, comprising:

a partial identification information generation section that divides the document information into a plurality of parts and generates partial identification information based on the respective parts of the document information and that represents, in an identifiable manner, respective parts of the document information, and that executes;

assigning a random number to respective parts of document information to be newly registered,

applying a hash function to the random numbers assigned to respective parts of the document information, to generate hash information,

generating partial identification information composed of position information indicating to which part of the document information the generated hash information corresponds and the hash information, and

generating, if any correction instruction has been given to the respective parts of the document information, the hash information for a part of the document information that has been corrected according to the correction instruction and correcting the partial identification information based on the hash information using a new random number to generate new partial identification information;

a partial correction information generation section that generates partial correction information which is information representing a correction history of a corrected part if any correction instruction has been given to the respective parts of the document information;

a management section that executes;

storing the document information to be newly registered and partial identification information generated by the partial identification information generation section in association with each other, and

storing, if any correction instruction has been given to the respective parts of the document information, document information corrected from the previous version, newly generated partial identification information, and partial correction information in an associated manner;

a registration document verification section that verifies, if there has been issued a request of verifying the validity of the document information, the validity of the document information by specifying a corrected part in the document information by using the partial correction information stored in association with the document information by the management section, comparing the partial identification information associated with the document information and partial identification information associated with the document information of the previous version before correction, and confirming that the correction has been made to the specified part and the part of the document information other than the specified part has not been corrected.

2. The digital document management system according to claim 1, wherein

the document information, partial identification information, and partial correction information include a signature.

3. The digital document management system according to claim 1, comprising a registration policy verification section that verifies whether the document has been corrected properly according to the policy information in the case where any correction has been made to the document information.

4. The digital document management system according to claim 1, wherein

the information managed by the management section is constituted by XML data having a hierarchical document structure.

5. The digital document management system according to claim 4, wherein

the partial identification information generation section corrects XML data having a hierarchical document structure according to a correction instruction for correcting respective parts of the document information to generate partial identification information with respect to all parent elements and child elements for both the part that has been corrected from the previous version and the part that has not been corrected therefrom.

6. The digital document management system according to claim 5, wherein

the partial identification information generation section generates partial identification information with respect to child elements and their belonging parent element only for the part that has been corrected from the previous version, and

the management section manages only difference partial identification information from the previous version.

13. The digital document management system according to claim 1, wherein the management section handles digital information as original document information corresponding to version numbers, and controls the content of the original document information managed based on its version numbers so that the content is hidden from unauthorized persons depending on the content thereof in the respective versions.

7. A digital document management method that manages document information created in a digital form by a computer, comprising:

a first partial identification information generation step that divides the document information into a plurality of parts and generates partial identification information based on the respective parts of the document information and that represents, in an identifiable manner, respective parts of the document information, and that

assigns a random number to respective parts of document information to be newly registered,

applies a hash function to the random numbers assigned to respective parts of the document information to generate hash information,

generates partial identification information composed of position information indicating to which part of the document information the generated hash information corresponds and the hash information;

a first registration step that registers the document information and the partial identification information in an associated manner;

a correction request reception step that makes the computer receive an instruction of correcting the document information;

a second partial identification information generation step that applies a hash function to the part of the document information that has been corrected according to the correction request to newly generate hash information using a new random number and corrects the partial identification information based on the newly generated hash information to generate new partial identification information;

a partial correction information generation step that generates partial correction information representing a correction history of a corrected part of the document information based on the correction request;

a second registration step that registers the document information corrected from the previous version, partial identification information generated in the second partial identification information generation step, and partial correction information in an associated manner; and

a registration document verification step that verifies if there has been issued a request of verifying the validity of the document information, the validity of the document information by specifying a corrected part in the document information by using the partial correction information stored in association with the document information in the second registration step, comparing the partial identification information associated with the document information and partial identification information associated with the document information of the previous version before correction, and confirming that the correction has been made to the specified part and the part of the document information other than the specified part has not been corrected.

14. The digital document management method according to claim 7, wherein the information managed by the management step is constituted by XML data having a hierarchical document structure.

15. The digital document management method according to claim 7, wherein the partial identification information generation step corrects XML data having a hierarchical document structure according to a correction instruction for correcting respective parts of the document information to generate partial identification information with respect to all parent elements and child elements for both the part that has been corrected from the previous version and the part that has not been corrected therefrom.

16. The digital document management method according to claim 7, wherein the partial identification information generation step generates partial identification information with respect to child elements and their belonging parent element for the part that has been corrected from the previous version while generating partial identification information with respect only to a parent element for the part where all the child elements belonging to the parent element have not been corrected.

17. The digital document management method according to claim 7, further comprising handling digital information as original document information corresponding to version numbers, and controlling content of the original document information managed based on its version numbers so that the content is hidden from unauthorized persons depending on the content thereof in the respective versions.

8. A non-transitory computer readable medium storing a digital document management program for managing document information created in a digital form, the program causing a computer to execute a process comprising:

a first partial identification information generation step that divides the document information into a plurality of parts and generates partial identification information based on the respective parts of the document information and that represents, in an identifiable manner, respective parts of the document information, and that,

assigns a random number to respective parts of document information to be newly registered,

applies a hash function to the random numbers assigned respective parts of the document information to generate hash information,

generates partial identification information composed of position information indicating to which part of the document information the generated hash information corresponds and the hash information; and

a first registration step that registers the document information and the partial identification information in an associated manner;

a correction request reception step that makes the computer receive an instruction of correcting the document information;

a second partial identification information generation step that applies a hash function to the part of the document information that has been corrected according to the correction request to newly generate hash information using a new random number and corrects the partial identification information based on the newly generated hash information to generate new partial identification information;

a partial correction information generation step that generates partial correction information representing a correction history of a corrected part of the document information based on the correction request;

a second registration step that registers the document information corrected from the previous version, partial identification information generated in the second partial identification information generation step, and partial correction information in an associated manner; and

a registration document verification step that verifies if there has been issued a request of verifying the validity of the document information, the validity of the document information by specifying a corrected part in the document information by using the partial correction information stored in association with the document information in the second registration step, comparing the partial identification information associated with the document information and partial identification information associated with the document information of the previous version before correction, and confirming that the correction has been made to the specified part and the part of the document information other than the specified part has not been corrected.

9. The non-transitory computer readable medium according to claim 8, wherein

the partial identification information generation step allows the computer to divide the document information into a plurality of parts and generate the partial identification information based on the respective parts of the document information.

10. The non-transitory computer readable medium according to claim 8, wherein

the information managed by the management step is constituted by XML data having a hierarchical document structure.

11. The non-transitory computer readable medium according to claim 8, wherein

the partial identification information generation step corrects XML data having a hierarchical document structure according to a correction instruction for correcting respective parts of the document information to generate partial identification information with respect to all parent elements and child elements for both the part that has been corrected from the previous version and the part that has not been corrected therefrom.

12. The non-transitory computer readable medium according to claim 8, wherein

the partial identification information generation step generates partial identification information with respect to child elements and their belonging parent element for the part that has been corrected from the previous version while generating partial identification information with respect only to a parent element for the part where all the child elements belonging to the parent element have not been corrected.

18. The non-transitory computer readable medium according to claim 8, wherein the program further causes the computer to handle digital information as original document information corresponding to version numbers, and control the content of the original document information managed based on its version numbers so that the content is hidden from unauthorized persons depending on the content thereof in the respective versions.