JP2000244730A - Document management apparatus and method using physical random numbers - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To increase the credibility of document management information of document data. A document management apparatus has a CPU and a random number generator for generating a physical random number. The CPU 11 embeds the physical random number fetched from the random number generator into the document data as an electronic watermark, and stores the physical random number in the CD-R 22 in association with the document management information of the document data. Further, the CPU 11 detects a physical random number from the input document data, searches the CD-R for the detected physical random number, and reads out document management information corresponding to the same physical random number as that of the document data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document management apparatus such as a personal computer for managing management information associated with document data in correspondence with physical random numbers, and a method therefor.

[0002]

2. Description of the Related Art Conventional computers and word processors have a function of automatically adding the creation date and time to a document file using an internal clock. However, the internal clock is likely to be out of order due to the low accuracy, and the date and time of creation of the document is generally unreliable because the user can easily adjust it. Therefore, when proof of a document creation date is required, such as a patent document, the creation date and time attached to such a document may lack credibility as legal evidence.

[0003]

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide
An object of the present invention is to provide a document management apparatus and a document management method which have high credibility of document management information such as the date and time of creation of a created document and copyright information, and which can easily verify the document management information.

[0004]

SUMMARY OF THE INVENTION A document management apparatus according to claim 1 of the present invention is a document management apparatus for managing document management information accompanying document data, comprising: a random number generator for generating a physical random number;
A memory for embedding a physical random number fetched from the random number generator in the document data in accordance with the input document data and outputting the document, and storing the physical random number in a recording medium in correspondence with the document management information of the document data. Means,
Reading means for detecting a physical random number from the input document data and reading document management information corresponding to the physical random number that matches the physical random number obtained by searching the detected physical random number in the recording medium. It is a feature.

[0005] A document management method according to a ninth aspect of the present invention comprises:
A document management method for managing document management information associated with document data, comprising: an embedding process of embedding a physical random number in document data; and storing the physical random number in a recording medium in association with the document management information of the document data. And a storage step. According to a twelfth aspect of the present invention, there is provided a document management method for document data in which a physical random number corresponding to accompanying document management information is embedded and the physical random number is recorded on a recording medium together with the document management information. , A method of verifying the document management information,
A detection step of detecting a physical random number from document data, a search step of searching for the detected physical random number in the recording medium, and a physical step of matching when a physical random number that matches the physical random number obtained in the search step exists. Reading out the document management information corresponding to the random number from the recording medium.

A document management method according to a fourteenth aspect of the present invention is a document management method for managing document management information attached to document data, wherein an embedding step of embedding a physical random number in the document data, A storage step of storing the document data in a recording medium in association with document management information; a step of detecting the physical random number from the document data; a search step of searching the detected storage medium for the detected physical random number; And reading the document management information corresponding to the matching physical random number from the recording medium when there is a physical random number matching the physical random number obtained in the search process.

[0007]

According to the present invention, the physical random number is embedded in the document data by associating the physical random number with the document management information attached to the document data, and the physical random number and the document management information are stored in the recording medium. By searching the recording medium for the physical random number detected from the document data, the document management information can be verified at any time.

[0008]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing a document management apparatus according to the present invention. In FIG. 1, the document management apparatus includes a system 10, which includes a CPU (central processing unit) 11, a hard disk device 12, a main memory 13, an input device 14, a display 15, a printer 16 , Data input / output device 17 and random number generator 1
8, an internal clock 19, and a recording medium writing / reading device 20.
It has a U bus 21.

The CPU 11 inputs / outputs and edits document data, displays an image on the display 15, prints on the printer 16, data communication for communicating with a communication satellite or an information network, generation of physical random numbers, determination of time, It controls writing and reading of a recording medium writing / reading device, and embedding and decoding of data. The input device 14
For example, the system 10 includes a keyboard, a mouse, a card reader, an image input device, and a voice recognition device, and commands and various information are input to the system 10 by a user.

The hard disk drive 12 has a system 1
No. 0 is installed with software for controlling various operations. The data input / output device 17 includes a floppy disk drive, an optical disk (CD) reading drive, or a communication line such as the Internet or an information network, and transmits various data including document data to the system 10 via the input / output device 17. Input and output.

The random number generator 18 generates a binary physical random number of, for example, 64 bits in response to a random number generation command from the CPU 11. However, the random number generator 18
Is not limited to the above configuration, and can generate a physical random number having an appropriate configuration. Internal clock 19
Is, for example, NTP (Network Time P
rotocol) server and SNTP (Simple Network Time Pro)
The server is connected via a communication line to a time server 23 existing outside the system 10 such as a server. Therefore, the clock is always or at a predetermined interval.
It fetches accurate time information from and synchronizes its time with standard time. In this manner, the third party is guaranteed that the clock 22 always displays the standard time in synchronization with the standard time. Note that the clock 19 is not limited to the time server, and may be connected to an appropriate device or institution that guarantees the credibility of the time display of the clock 19.

The recording medium writing / reading device 20 includes a CPU 1
In response to a write command from the CPU 1, data supplied via the CPU bus 21 is written and stored in a write-once optical disc (hereinafter, referred to as a CD-R) 22 as a recording medium. Thus, the system 10 of the present invention is configured. Next, the operation of the above embodiment will be described.

First, FIG. 2 shows the embedding of document management information.
This will be described based on the flowchart shown in FIG. In the present invention, the document management information includes at least the document name and creation date and time of the original document data, and may further include copyright information such as the name of the creator. When an instruction to embed document management information is input from the input device 14, the CPU 11 transfers the target original document data to the system 1 via the input / output device 17.
It is taken into 0 (step S10). Next, the CPU 11
Sends a random number generation command to the random number generator 18 and captures a physical random number generated in response to the command (step S11), and determines the capture date and time of the physical random number by the clock 19 (step S12). Next, the acquired physical random numbers are embedded in the original document data as a digital watermark, and the created watermarked document data is temporarily stored in, for example, the main memory 13 (step S13). In this way, the physical random number is made to correspond to the acquired original document data, and thereafter, the physical random number is attached to the document data as a digital watermark.

Next, the CPU 11 generates an ID (Identifi) including, as a data set, the physical random number, the date and time of the capture, and the document management information of the original document managed by the random number.
cation) file is created, for example, as shown in FIG. 4 (step S14). In this ID file, the date and time of generation of the random number determined by the standard time indicated by the clock is treated as corresponding to the date and time of creation of the original document, and thereafter, proves the date and time of creation of the original document. Next, CPU1
1 sends this ID file to the writing device 20, and the writing device 20 responds to a write command from the CPU 11
The D file is written and stored on the CD-R 22 (step S15). The CPU 11 reads the ID file CD-R2
Upon completion of the writing to No. 2, the watermarked document data temporarily stored in the memory is output to the data input / output device 17 (step S16).

In this way, the physical random number is embedded in the original document as a digital watermark and output,
The CD-R 22 is created as a recording medium necessary for decoding such a physical random number. Next, verification of document management information will be described with reference to the flowchart shown in FIG.

When a command to output document management information is input from the input device 14, the CPU 11 captures target watermarked document data via the data input / output device 17 (step S20), and converts the watermarked document into a digital watermark. And detects the embedded physical random number (step S21).
Next, the CPU 11 loads the ID file from the CD-R 22 (step S22), and searches the ID file for a physical random number that matches the detected physical random number (step S2).
3). In step S24, if a physical random number that matches the detected physical random number exists in the ID file, in step S25, the document management information such as the document name and the document creation date and time corresponding to the matched physical random number is read from the ID file. It is displayed on the display 15 or printed out by the printer 16 for output. In step S24, if there is no physical random number that matches the detected physical random number in the ID file, "not applicable" is output by display or printing (step S26).

In this manner, by comparing the physical random number detected from the watermarked document data with the ID file, the document management information of the watermarked document data can be read and verified. As described above, the document management apparatus of the present invention employs a configuration in which a physical random number is associated with document management information and the original document management information is verified from the physical random number as needed.

Since it is stochastically difficult to generate the same physical random number twice, actually, the same random number does not exist and is unique. Therefore, while storing the random number in the storage medium in association with the document management information of the document data, if the random number is embedded in the document data, the document management information of the document data corresponding to the random number is verified based on the unique random number. can do. Further, since the document management information is managed through the intermediation of random numbers, the management information of the document data can be protected from fraud such as erasure and tampering. Further, since the random number is embedded in the document data as a digital watermark, the embedded random number itself can be protected from fraud such as erasure and falsification.

In addition, the collation between the random number and the document management information includes:
Since a recording medium different from the document data is required, even if the physical random number can be decrypted from the document data, the authenticity of the document management information obtained from the document data is not guaranteed by the random number alone. On the other hand, the essential document data cannot be obtained by using only the recording medium. Therefore, according to the present invention, the credibility of the document management information can be guaranteed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a document management device according to the present invention.

FIG. 2 is a diagram showing an operation flow at the time of embedding a random number by the document management apparatus of the present invention.

FIG. 3 is a diagram showing an operation flow at the time of reading document management information by the document management device of the present invention.

FIG. 4 is a diagram showing information stored on a recording medium of the present invention.

[Explanation of Signs of Main Parts]

 Reference Signs List 10 system 11 CPU 18 random number generator 22 recording medium

Continuation of the front page (72) Inventor Goichiro Nagai 858, Maga-ku, Miyama-ku, Kawasaki-shi, Kanagawa Prefecture 505 Casa Verde Miyazakidai (72) Inventor Toyohiko Hirota 680-4 Kawazu, Iizuka-shi, Fukuoka F-term (reference) 5B009 SA14 VA05 VA11 VA11 5B017 AA06 BA09 CA16 5B082 EA07 EA11 EA12 GA11 GA17 5C076 AA14 BA03 BA04 BA06

Claims (14)

[Claims] 1. A document management device for managing document management information attached to document data, comprising: a random number generator for generating a physical random number; and a physical data fetched from the random number generator in accordance with input document data. A storage unit for embedding a random number in the document data and outputting the same, and storing the physical random number in a recording medium in association with the document management information of the document data, and detecting and detecting the physical random number from the input document data. A document management apparatus, comprising: reading means for reading document management information corresponding to a physical random number that matches a physical random number obtained by searching for a physical random number in the recording medium. 2. The system according to claim 1, further comprising: a clock for displaying a standard time, wherein the document management information includes a date and time of creation of the document data; 2. The storage medium according to claim 1, wherein the date and time of the document data is stored as a date and time when the document data is created.
Document management device as described. 3. The document management apparatus according to claim 2, wherein the clock is connected to an external device and synchronized with a standard time. 4. The document management apparatus according to claim 2, wherein the clock is connected to a time server via a communication line to synchronize with a standard time. 5. The document management apparatus according to claim 1, wherein the document management information includes copyright information of document data. 6. The document management apparatus according to claim 1, wherein the storage unit embeds the physical random number as electronic watermark in document data. 7. The document management apparatus according to claim 6, wherein the reading unit detects a physical random number by decoding a digital watermark from the input document data. 8. The document management apparatus according to claim 1, wherein said storage medium is a write-once optical disk. 9. A document management method for managing document management information attached to document data, comprising: an embedding process of embedding a physical random number in document data; and causing the physical random number to correspond to document management information of the document data. A document management method, comprising: a storage step of storing in a recording medium. 10. The document management information includes a date and time of creation of document data, and further includes a step of determining the capture date and time of the physical random number using a clock that displays a standard time. The document management method according to claim 9, wherein an embedded date and time are stored in a storage medium as the date and time when the document data was created. 11. The document management method according to claim 9, wherein the embedding step embeds the physical random number as an electronic watermark in the document data. 12. The document management information is verified against document data in which a physical random number corresponding to the accompanying document management information is embedded and the physical random number is recorded on a recording medium together with the document management information. A detection process of detecting a physical random number from document data, a search process of searching for the detected physical random number on the recording medium, and a physical random number that matches the physical random number obtained in the search process. Reading the document management information corresponding to the physical random number that matches in the case from the recording medium. 13. The document management method according to claim 12, wherein in the detection step, a digital watermark is decoded from document data, and a physical random number is decoded from the decoded physical random number. 14. A document management method for managing document management information attached to document data, comprising: an embedding process of embedding a physical random number in document data; and causing the physical random number to correspond to document management information of the document data. A storage step of storing the physical random number from the document data; a search step of searching the detected storage medium for the detected physical random number; and a physical random number obtained in the search step. Reading the document management information corresponding to the physical random number that matches when the physical random number exists from the recording medium.