JPH02115995A - Data control system and recording medium for such system - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a management system for data recorded on an optical recording medium, a magnetic recording medium, etc., and a recording medium therefor.

[Conventional technology]

A data file system is known as a system using large-capacity recording media such as optical disks and magnetic disks, which records and manages a large amount of necessary data on the recording medium, but this data file system is also used in various fields. For example, it has come to be used to manage data that is only available to designated people, such as personal data. An example of a system for managing this personal data is a medical data management system, which stores personal X-ray photographs and the like, and which must be kept confidential from others. There is.

On the other hand, an IC card system is conventionally known as a data file system that maintains the confidentiality of personal data. This uses an IC card that has a built-in microcomputer and memory, and the necessary data is stored in the memory and a password is stored in the microcomputer. The microcomputer can read data from the memory only when the password stored in the computer is lost.

[Problem to be solved by the invention]

In the above-mentioned IC card system, the microcomputer in the IC card determines whether or not data can be read from the memory depending on the failure or mismatch of the PIN as described above. A high level of confidentiality can be maintained. In other words, the microcomputer, which is the means for reading data from the memory, is built into the IC card together with this memory, and it operates only by a password; the microcomputer cannot operate by any other means, so the confidentiality of the data cannot be guaranteed. It can be maintained.

On the other hand, recording media such as optical disks and magnetic disks only record data, and data can be easily read by attaching them to a drive device. In contrast to an IC card system, it is conceivable to use a password to determine whether or not the drive device can read data from the recording medium.
This is possible with a specific drive device, and data reading can be easily performed using other drive devices or existing drive devices that do not require a password.

As described above, it has conventionally been impossible to maintain the confidentiality of data in file systems using optical disks, magnetic disks, and the like.

SUMMARY OF THE INVENTION An object of the present invention is to provide a data management system and a recording medium therefor that solves such problems and makes it possible to maintain the confidentiality of data recorded on a recording medium.

[Means to solve the problem]

In order to achieve the above object, the data management system according to the present invention has scrambled data and one scramble program recorded on a recording medium, and when reproducing desired data from the recording medium, The scramble program is read out and stored in a scramble table of a data processing device, and the desired data reproduced from the recording medium is descrambled into original data in accordance with the scramble program in the scramble table.

The scramble program is input from the outside and recorded on the recording medium, and when recording desired data, the scramble program is read from the recording medium, and the desired data is scrambled using the scramble table according to the scramble program. Record on a recording medium.

Further, the recording medium according to the present invention includes a user data area in which a user can record and reproduce desired data as desired, and the data recorded in the user data area is scrambled, and the data is descrambled. A scramble program for restoring the data to the original data is recorded in an arbitrary location specified by the user in the user data area.

[Effect]

Since the data recorded on the recording medium has been scrambled, the original data cannot be obtained simply by reproducing the data from the recording medium.

The original data is obtained only when the data reproduced from the recording medium is descrambled using a scrambling program recorded on the recording medium. Therefore, when the scramble program cannot be read from the recording medium, the original data cannot be obtained from the recording medium.

Furthermore, in the recording medium, the scramble program is recorded in an arbitrary location specified by the user, although it is within the user data area, so the scramble program cannot be read unless the user knows this recording location.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the data management system according to the present invention, in which 1 is a host computer, 11 is a scramble table, 2 is a disk drive device, and 3 is a block diagram showing an embodiment of the data management system according to the present invention.
4 is an optical disk, 4 is an image scanner, and 5 is a display device.

In the figure, the optical disc 3 is, for example, 15O-91
This is a 5.25-inch optical disc with a cartridge conforming to the 71 standard, and as shown in FIG. 2, it has a user data area and a directory data area. The user data area records a large amount of image data that requires personal management, such as X-ray photographs, and the directory data area contains directories such as the start address, data length, file name, date, etc. for each image data. Data is recorded. A scramble program is also recorded in the user data area.
According to this, the image data and directory data are scrambled. This scramble program is recorded in the user data area, but at any location designated by the user.

In FIG. 1, when reproducing desired data from the optical disc 3, the user first specifies the required file name and address AA (FIG. 2) representing the recording position of the scramble program on the optical disc 3. Therefore, the host computer 1 takes in the file name and address AA, reads the scramble program from the optical disk 3, and stores it in the scramble table 11. After the above processing is performed, the host computer 1 causes the disk drive device 2 to start reproducing data from the optical disk 3.

In the optical disc 3, first, the directory data area is reproduced, and the scrambled directory data is reproduced and supplied to the host computer 1. In the host computer 1, the supplied directory data is descrambled according to the scramble program stored in the scramble table 11, and the file name in this directory data is compared with the file name specified by the user. Ru. When the two match, the start address and data length are extracted from the directory data including this file name and supplied to the disk drive device 2, and the image data of the file name specified by the user is reproduced from the user data area of the optical disk 3. let This reproduced image data is supplied to the scramble table 11 of the host computer 1, and similarly to the directory data, it is subjected to descrambling processing according to the previous scramble program stored in the scramble table 11. The signal is converted into a signal and supplied to the display device 5.

The scrambling program is recorded on a completely unused optical disc or when recording the first image data on this unused optical disc. This scramble program is input into the host computer 1 by the user, but may have a predetermined configuration or may have an arbitrary configuration formed by the user.

In any case, when data is reproduced, data can be descrambled only by the scramble program read from the optical disc.

When recording a scramble program, the scramble program is input and the recording location of this scramble program on the optical disc 3 is designated by its start address AA. As a result, the host computer 1 starts up the disk drive device 2 and drives the optical disk 3.
Write this scramble program to the specified location above without scrambling. Note that it is preferable that the data length of the scramble program is constant;
As a result, the scramble program can be correctly read from the optical disc 3 simply by specifying the start address AA.

When recording image data on the optical disc 3, first,
The user specifies the start address AA of the recording location of the scramble program on the optical disk 3. As a result, the host computer 1 uses the disk drive device 2.
is activated to read out a scramble program from the optical disc 3, and this scramble program is stored in the scramble table 11. Next, a desired image is inputted by the image scanner 4, and the image signal is converted into digital image data and supplied to the host computer 1. The host computer 1 scrambles the scrambled image data according to the scramble program stored in the scramble table 11 and supplies it to the disk drive device 2. As a result, the scrambled image data becomes user data on the optical disk 3. At the same time, directory data corresponding to this image data is similarly scrambled and recorded in the directory data area of the optical disc 3.

As described above, only when the scramble program is correctly read from the optical disc 3, the directory data reproduced from the optical disc 3 is restored to the original correct data, and the directory data including the file name specified by the user is restored. Desired image data is reproduced from the optical disc 3 based on the start address and data length,
The original correct image data is restored using the scramble table 11 to generate an analog image signal, and the display device M, 5 displays the image required by the user. Furthermore, since the scramble program is written in any location specified by the user on the optical disc 3, it is almost impossible for a third party to read it correctly.

Furthermore, when the scramble program cannot be read, recording onto the optical disc 3 is also not possible.

This also makes it possible to prevent the data on the optical disc 3 from being destroyed by a third party.

Therefore, only a specific user who can instruct the recording position of the scramble program on the optical disc 3 can correctly reproduce data from the optical disc 3. Therefore, when an image such as an X-ray photograph that is not desirable to be known to others is stored on this optical disc 3, only the user who owns this optical disc 3 knows the recording position of the scramble program. By keeping these data confidential, it is possible to keep these data confidential.

Next, the scrambling method used in this embodiment will be explained.

Scrambling is a process that changes the arrangement of bits that make up data, thereby converting the data into data that is completely different from the original data.

Therefore, by restoring the bit arrangement of the scrambled data (descramble processing), the original data is restored. This scrambling process is performed according to a scrambling program, and the original data is restored by descrambling the data using the same scrambling program.

FIG. 3 shows a specific example of image data. This image data has a resolution of 512 dots (pixels) in the horizontal direction and 512 dots in the vertical direction, and one dot is 8-bit data. Therefore, if this image data represents a black and white image, it will be a multivalued image with 256 gradations.

Scrambling and descrambling of such image data is performed in units of 8 bits.

Therefore, it is performed for each dot (pixel). Although there are various methods of scrambling, a scrambling process in which 8 bits are rearranged will be explained with reference to FIG.

Figure 4 shows one of the bit rearrangement processes,
This process is performed by a scramble program read from the optical disc (FIG. 1).

In FIG. 4(a), this process consists of 8 bits D1.D, where D is the MSB (most significant bit) and Do is the LSB (least significant bit). Dh, Dl, ・・・・・・Dr
, Do, the upper 4 bits D, ~D4 are shifted 4 bits to the lower side, and the lower 4 bits D, ~D0 are shifted 4 bits to the upper side, so that the bits are as shown in Fig. 4(b). This allows you to obtain sorted data. This is the scrambling process by the scrambling program, and in the descrambling process, the reverse process from FIG. 4(b) to FIG. 4(a) is performed using the same scrambling program.

A scrambling program that performs scrambling and descrambling processing on all optical discs may be used.

In this case, the scramble program is the same for all optical discs, but since the location where the scramble program is recorded on the optical disc is different for each optical disc or for each user, even if the configuration of the scramble program is known to someone else, There is no problem as long as the recording location is not known to others. Of course, the user may create and use a scramble program himself, or the scramble program may be different for each optical disc.

Since the user does not need to know the contents of the scramble program, the manufacturer of the optical disc writes the scramble program on the optical disc in advance, and only the user of this optical disc is notified of the address representing the recording position of this scramble program. You can also do this.

Although one embodiment of the present invention has been described above, the present invention is not limited to this embodiment. For example, other recording media such as not only optical disks but also optical cards, magnetic disks, magneto-optical disks, and magnetic tapes may be used. The scramble table 11 may be provided in either a software program or hardware, and may also be provided in another location such as the disk drive device 2.

〔Effect of the invention〕

As explained above, according to the data management method according to the present invention, data can be correctly obtained from the recording medium only by using the scramble program recorded on the recording medium, so the scramble program can be read from the recording medium. Only users who are qualified can actually use the recording medium, and the data recorded on the recording medium can be kept confidential.

Further, according to the recording medium of the present invention, the recording position of the scramble program on the recording medium can be arbitrarily determined by the user who owns the recording medium, and it is almost impossible for others to read the scramble program. It can be done.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a data management system according to the present invention, FIG. 2 is a schematic diagram showing a data area of a recording medium according to the present invention, FIG. 3 is a diagram showing an example of the structure of image data, and FIG. FIG. 4 is a diagram showing an example of the scrambling and descrambling processing of the embodiment shown in FIG. 1. 1...Host computer, 11...
・・・・・・Scramble table, 2・・・・・・
・・Disk drive device, 3・・・Optical disk, 4・・・・・Image scanner, 5・
...Display device. No.! Figure 2 Tes 7 Dora 1 Buyahi! 3 light 6th figure 2 figure 3 figure 4

Claims (4)

[Claims] (1) A management method for data recorded on a recording medium includes a data processing device equipped with a scramble table, and the recording medium records scrambled data and one scramble program. When reproducing desired data from a recording medium, the scramble program is read from the recording medium and stored in the scramble table, and the desired data reproduced from the recording medium is restored to its original form in the scramble table according to the scramble program. A data management method characterized by descrambling data. (2) The data processing method according to claim (1), wherein the scramble program is input from an external source and recorded on the recording medium. (3) In claim (1) or (2), the scramble program is read from the recording medium and stored in the scramble table, and desired data input from the outside is scrambled in the scramble table according to the scramble program. A data management method characterized by processing and recording on the recording medium. (4) In a recording medium equipped with a user data area in which a user can arbitrarily record and reproduce desired data,
The data recorded in the user data area has been scrambled, and a scramble program for descrambling the data and restoring it to the original data is stored in an arbitrary location specified by the user in the user data area. A recording medium for data management characterized by being recorded.