JPH10222063A - Digital information management system, terminal device, information management center, and method of controlling digital information - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to prevent illegal copy without losing convenience for proper users. SOLUTION: When digital information is used, a registration number and a registration number authentication corresponding to the digital information used from a terminal equipment 2 are transmitted to an information management center 1. The information management center 1 examines a validity of the received registration number and also checks the conditions for the use of the corresponding digital information, and transmits data indicating a permission for the use if the number has a validity, and transmits data for inhibiting the use to terminal device 2, if the number is not duly permitted for the use. The terminal device 2 is arranged so that the digital information is usable thereon only when it receives a permission for the use.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital information management system and a digital information management method for preventing unauthorized use of digital information stored in a terminal device, and more particularly to a case where a specified number of times or a specified period is exceeded. The present invention relates to a digital information management system and a digital information management method for preventing unauthorized users from using digital information.

[0002]

2. Description of the Related Art In recent years, digitization of texts, voices, still images, moving images, and the like for use on computers has been rapidly increasing. However, since digital data has the property that the exact same data as the original data can be easily copied / created on a computer, there arises a problem that illegal copying violates the rights of copyright holders and data sellers. .

In recent years, in addition to simply preventing unauthorized copying, the number of times data is used and the number of times digital data and the like are reproduced are limited in terms of the number of uses and the period of use in order to have the user understand the usefulness of the data. There is also a growing need to collect fees depending on the situation. Methods for solving these problems and realizing the needs are described in, for example,
No. 27 is disclosed. This is a method of limiting the number of times the software is used. In brief, first, the software provider sends the limited number of uses and the initial value of the number of uses to the user's computer (terminal device) via communication means. Then, these are recorded on a recording medium in the user's computer. Then, the number of times of use is updated at the time of executing the software, and the number of times of use is compared with the number of times of use restriction.

However, in this method, the number of times of use and the number of times of use are recorded and managed in the user's computer, so that a dedicated computer or hardware or operating system whose specifications are publicly used is used, not only a dedicated computer. In a so-called general computer (personal computer), a user having a high technical level may rewrite the number of times of use or the number of times of use limit. Also,
Since it is necessary to inform the software provider of the telephone number and address of the computer to be used, there has been a problem in terms of complicated procedures and privacy protection.

Another method is disclosed in Japanese Patent Application Laid-Open No. Hei 7-131452. This is because when downloading digital information stored in an information center from a terminal device via a communication line, the digital information is encrypted so that the digital information can be used only by the terminal device, and the digital information is The usage conditions are downloaded and stored in the confidential processing unit in the terminal device. Then, when using the information, it is checked whether or not a predetermined use condition stored in the confidential processing unit is met. If the condition is not met, the use is prohibited.

[0006]

In this latter method,
It is necessary that the confidential processing unit for storing the common key of the encryption, usage conditions, usage history, etc. in the terminal device be completely hidden from users, but in order to acquire more users, Preferably, the terminal device is a computer (personal computer) having a general configuration. However, it is very difficult to implement such a confidential processing unit on a computer with a very common configuration without adding a special device with tamper resistance that does not allow users to read and write even by unauthorized methods. Met. In addition, when a special device is used, the cost of the terminal device is increased, and the number of users is limited, so that there is a practical problem.

Furthermore, in the above two methods, the number of terminal devices that can use the purchased software or digital information is limited to only one downloaded terminal device. Even if it is desired to use the digital information in both the office and the workplace, it is impossible to use such digital information unless the terminal device is carried and moved, which may impair the convenience of a legitimate user. As another method, when digital information is used, a method of preventing illegal copying by downloading the digital information from the server each time and not storing the digital information in the terminal device can be considered, but the communication cost increases, There was a problem that it took time to download.

Accordingly, the present invention prevents unauthorized copying without impairing the convenience of a legitimate user, and restricts the number of times and period of use to use data and the number of times of reproducing digital moving images and the like. It is an object of the present invention to provide a digital information management system capable of collecting a fee according to the information.

[0009]

As means for achieving the above object, the following digital information management system is provided.
It is intended to provide a terminal device, an information management center, and a digital information management method.

[0010] 1. A digital information management system in which a terminal device and an information management center are connected via a communication line and manages digital information stored in the terminal device, wherein the terminal device communicates with the information management center. First communication means for performing digital information, digital information storage means for storing a registration number for identifying the digital information, a registration number authenticator, and the digital information body, and first control for controlling a use procedure of the digital information Means for communicating with the terminal device, use condition storage means for storing and storing the registration number and its use condition, and using the authenticator. A digital information management system, comprising: authentication processing means for authenticating the registration number; and second control means for controlling the entire information management center.

2. Communication means for communicating with the information management center; digital information storage means for storing a registration number for identifying digital information, a registration number authenticator, and a digital information body; and control means for controlling a use procedure of the digital information; A terminal device comprising:

3. The registration number is set so that a bit string of a specific part of the registration number or the authenticator of the registration number matches a bit string of a specific part of the digital information main body, and the digital information storage means matches the bit string. 2. The bit stream is superimposed and arranged. The terminal device as described in the above.

4. Communication means for communicating with the terminal device;
Use condition storage means for storing a registration number and use conditions thereof, authentication processing means for authenticating the registration number using the authenticator, and control means for controlling each of the means. Information management center.

5. 3. The registration number is set so that a bit string of a specific part of the registration number or an authenticator of the registration number matches a bit string of a specific part of the digital information body. Information management center described.

6. A digital information management method for managing digital information stored in a terminal device, wherein a registration number for identifying the digital information and a registration number authenticator are connected from the terminal device via a communication line. A first procedure for transmitting to the management center, a second procedure for confirming the validity of the registration number received by the information management center using the registration number authenticator and an encryption key, A third procedure for confirming whether the digital information corresponding to the registration number received by the server matches the use condition, and indicating that use is permitted if the digital information matches the use condition at the information management center. A fourth procedure of transmitting data to the terminal device, and transmitting data indicating use prohibition to the terminal device if the usage condition is not met;
A fifth procedure for enabling the digital information to be used only when the terminal device receives data indicating permission to use the digital information.

[7] 7. The digital device according to the above item 6, wherein a value obtained by encrypting the registration number or a value obtained by substituting the registration number into a one-way hash function with an encryption key of the information management center is used as the registration number authenticator. Information management method.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A digital information management system according to the present invention, as shown in FIG.
Is a system connected via the communication line 3, and the information management center 1 records and manages the usage conditions and usage status of digital information. Then, as shown in FIG. 2, the terminal device 2 communicates with the information management center 1 (first communication unit).
4, a digital information storage means 6 for storing a registration number capable of uniquely identifying digital information, an authenticator of the registration number, and a digital information main body, and a control means for controlling a use procedure of the digital information (first control means) ) 5, input means 8 and output means 9.

As shown in FIG. 3, the information management center 1 includes a communication means (second communication means) 101 for communicating with the terminal device 2 and a use condition for storing and storing a registration number and its use condition. Storage means 103, authentication processing means 104 for authenticating a registration number, and control means (second control means)
102. A digital information management method for actually managing digital information in the digital information management system having such a configuration will be described.

First, when selling the digital information, the information seller adds a registration number and an authenticator of the registration number to the digital information main body, and also registers the registration number and its use condition in the information management center 1. Register in the storage unit 103. Here, as a method of adding the registration number and the authenticator of the registration number to the digital information main body, for example, the digital information is installed in advance, or the CD-ROM is used.
If the digital information has already been stored in the digital information storage means 6 of the terminal device 2 when the digital information has already been stored in a portable recording medium such as May be supplied to the terminal device 2 via the communication line 3 and digital information may be supplied via the communication line 3 together with the digital information.

After registration, the control means 5 of the terminal device 2 allows the user to use the digital information on the terminal device 2.
When the instruction to use is given, after the following processing is performed between the terminal device 2 and the information management center 1, digital information can be used. First, the terminal device 2 transmits the registration number and the authenticator of the registration number to the information management center 1. The information management center 1 checks the usage conditions of the digital information corresponding to the received registration number, and checks whether the digital information is in a legally usable state. If the use is legitimate, data indicating use permission is transmitted to the terminal device 2. If the use is not valid, data indicating use prohibition is transmitted to the terminal device 2. The terminal device 2 controls so that the digital information can be used only when the data received from the information management center 1 indicates the use permission.

By using such a method, it becomes difficult for the user to illegally change the use conditions, so that the number of times of use and the expiration date of the digital information can be accurately managed. Further, the terminal device 2 according to the present invention does not require an encryption processing unit which requires complicated processing. Also, it does not store common keys or secret keys that require confidentiality. Further, since the use conditions and use histories which need to be hidden from the user are not stored, the confidential processing unit unlike the conventional example is not required. Therefore, even when a computer having a general configuration without a special device is used as the terminal device 2, it is possible to accurately manage the number of times of use and the expiration date of digital information.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the digital information management system of the present invention will be described with reference to the drawings. FIG. 1 is a diagram showing the overall configuration of the present embodiment. In FIG. 1, a terminal device 2 that uses digital information and an information management center 1 that manages conditions for using digital information are connected by a communication line 3 such as a telephone line, a dedicated line, or a LAN. FIG. 2 shows a configuration example of the terminal device 2. In the case of a personal computer, a portion indicated by a dotted line in the figure is a personal computer main body, to which input means 8 such as a keyboard and a mouse and output means 9 such as a display are connected. A communication unit 4 for communicating with the information management center 1, a registration number capable of uniquely identifying digital information, an authenticator of the registration number, and digital information for storing the digital information main body are surrounded by a dotted line. It has a storage means 6 and a control means 5 for controlling a procedure for using digital information.

The communication means 4 is composed of a modem, a LAN controller or the like according to the type of the communication line 3.
It communicates with the information management center 1 according to an instruction from the control means 5. The digital information storage means 6 is composed of a hard disk, a floppy disk, an MO disk, or another nonvolatile memory. Then, for one piece of digital information, a registration number for identifying the digital information, an authenticator of the registration number, and a digital information body are stored.

The control means 5 comprises a CPU, a RAM, a ROM, and the like, and controls each section of the terminal device 2 in accordance with a predetermined procedure when a user uses digital information. The input unit 8 includes a keyboard, a mouse, operation buttons, a remote controller, and the like, and is used to give the digital information to be used by the user and an instruction of the result of selecting the use method to the control unit 5. Information output means 9
Is an output device such as a display, a speaker, and a printer, and an appropriate output device is selected according to the type of digital information, such as a display for a still image or a moving image and a speaker for audio.

FIG. 3 shows the configuration of the information management center 1. The information management center 1 includes a communication unit 101 for communicating with the terminal device 2, a use condition storage unit 103 for storing and storing use conditions, an authentication processing unit 104 for authenticating a registration number, and a control unit 102. It is configured.

The use condition storage means 103 stores a use condition table in the format shown in FIG. In the table shown in FIG. 4, the registration number is a number for uniquely identifying digital information managed by the information management center 1. This registration number is the same as the registration number stored in the digital information storage means 6 of the terminal device 2. As described later, the registration number may be assigned such that a part of the bit string of the registration number matches a part of the bit string of the digital information body. The period restriction flag is a flag indicating whether or not the use period is restricted. The period restriction flag is set to “1” when the use period is restricted, and is set to “0” when not restricted. The number-of-times restriction flag is a flag indicating whether or not to limit the number of times of use, and is set to “1” when the number of times of use is restricted, and set to “0” when not. The permission start date and time is valid when the period restriction flag is "1", and indicates the year, month, day, and time when the use permission is started. The permission end date and time is valid when the period restriction flag is “1”, and indicates the year, month, day, and time when the use permission ends. The usable count is valid when the count limit flag is “1”, and indicates the number of usable times in the future. Therefore, when the number-of-times restriction flag is "1" and this field becomes "0", it cannot be used. When both the use period and the number of times of use are restricted, both flags are set to “1”.

In the digital information management system having such a configuration, a digital information seller can sell digital information to a user by downloading digital information or the like, or can use a portable recording medium such as a CD-ROM or a pre-installed digital information. When a user who has already acquired digital information is registered by the user, a predetermined instruction is given to the control means 102 of the information management center 1 via an input means (not shown) or a management terminal (not shown). The use condition table stored in the use condition storage unit 103 is set according to the procedure.

First, a number that is not used as a registration number in the use condition table is selected as a new registration number N (step S11). Next, register the registration number on the digital information
N is added (step S12). This will be described in detail later. Next, the registration number N is written in a new entry of the use condition table (step S13). Then, various usage restrictions are set according to the contents of the digital information and the contract with the user. First, when the use period is limited (step S14 → YES), the period limit flag is set to “1”, and the permission start time and the permission end time are set in the permission start date and time field and the permission end date and time field, respectively (step S14). S1
Five). When it is not necessary to set either the permission start time or the permission end time, the field is set to a predetermined initial value (for example, 0). If the usage period is not restricted (step S14 → NO), the period restriction flag is set to “0”, and the permission start time and the permission end time are each set to a predetermined initial value (for example, 0) (step S16).

After the setting of the use period, the process proceeds to the setting of the number of uses in step 17. If the number of times of use is to be limited (step S17 → YES), the number-of-times limit flag is set to “1” and a usable number field is set (step S18). For example, if you want to allow three uses,
Set this field to "3". If the number of times of use is not limited (step S17 → NO), the number-of-times limit flag is set to “0”, and the available number field is set to a predetermined initial value (for example, 0) (step S19). This completes the setting of the usage condition table.

Further, the digital information seller gives a predetermined instruction to the control means 102 of the information management center 1 via input means (not shown) or a management terminal to create distribution data to be supplied to the terminal device 2. Examples of the format of the distribution data are shown in FIGS. 6 (A), (B), (C) and (D). The registration number authenticator 52 in the figure is created by the authentication processing unit 104 of the information management center 1. Note that the distribution data shown in the figure is a format when the digital information main body 54 is supplied together with the digital information main body 54 via the communication line 3 or a portable recording medium, and the digital information main body 54 is already supplied to the terminal device 2. In this case, the digital information main body 54 is created from the format shown in FIG. 2 in a form in which the digital information main body 54 is omitted, supplied to the terminal device 2, and recreated in the terminal device 2 into the format shown in FIG.

The format shown in FIG. 6A is a basic format, and has a format type 5 having a bit length P.
1, a registration number authenticator 52 having a bit length Q, a registration number 53 having a bit length S, and an information body 54 having a bit length U are arranged side by side. In the format shown in FIG. 6B, the last V bit of the registration number 53 and the first V bit of the information body 54 match, and the common bit is superimposed on the terminal device 2.
In the digital information storage means 6. Similarly, in the format shown in FIG. 4C, the first V bit of the registration number 53 and the last V bit of the information body 54 match, and the common bit is superimposed on the digital information storage means 6 of the terminal device 2. Is to be stored. (D)
Is the last V of the registration number authenticator 52.
The bit and the first V bit of the information body 54 match, and the common bit is superimposed and stored in the digital information storage means 6 of the terminal device 2.

When the format shown in FIGS. 6B, 6C, and 6D is used, the terminal device 2 sets the registration number 53 or the registration number authenticator 52 to the registration number of another digital information. If it is replaced with a registration number authenticator, part of the data of the information body is also rewritten, and the information body 54 cannot be used normally. Therefore, such misconduct can be suppressed. Further, the memory capacity of the digital information storage means 6 can be reduced by the amount of the overlap.
6 (B), (C), and (D) of FIG. 6 are examples, and use another format in which a part of the bit string of the registration number or the registration number authenticator and a part of the information body are overlapped. You may. Hereinafter, description will be given with reference to FIG. 1B as an example of such a format.

In the distribution data shown in FIG. 6, the format type 51 is a flag indicating whether or not a registration number 53 or a part of the registration number authenticator 52 is arranged so as to overlap a part of the information body 54. . For example, FIG.
Is set to "1" when they are superimposed as shown in the figure, and "0" when they are not superimposed as shown in FIG. The bit length P of the format type 51, the bit length Q of the registration number authenticator 52, the bit length S of the registration number 53, and the bit length V of the registration number 53 and the information body 54 which are superimposed are fixed lengths. Is stored and managed in the control means 5 of the terminal device 2. The bit length U is a variable length that changes depending on the contents of the information body 54.

When using a format as shown in FIG. 3B, the information management center 1 first extracts a V bit from the head of the information body, and places it in the last V of the registration number.
Assign to bits. Then, the remaining (SV) bits are set so that the new registration number does not become the same as another registration number already registered.

Next, the authentication processing means 1 of the information management center 1
FIG. 7 shows the structure of the circuit 04, which will be described below. The digital information seller creates an encryption key Ks in advance and stores it in the encryption key storage unit 81 of the authentication processing unit 104. The authentication processing unit 104 includes an encryption key storage unit 81, an encryption function operation unit 83, a one-way hash function operation unit 84, and a selector 85. The one-way hash function operation unit 84 It calculates and outputs short fixed-length data H (X) from input data X of an arbitrary length to be input. It is extremely difficult to calculate the input data X from the operation output H (X), and the probability that the same H (X) value can be obtained from a plurality of different Xs is extremely small. It is an operation unit.

The encryption function operation unit 83 has a function of encrypting the input data Y using the encryption key Ks and a predetermined encryption function F (). Here, the encryption key Ks is information that only the digital information seller knows and does not inform the user (terminal device 2). Therefore, F (Ks, Y) can be calculated only by the digital information seller (information management center 1). Conversely, if F (Ks, Y) is correctly calculated, it means that the digital information seller has calculated, and F (Ks, Y) has a function as an authenticator.

The registration number authenticator Vn sets the selector 85 on the f side, gives the registration number N to the input terminal, and performs encryption by the operation of the equation (1), or sets the selector 85 on the e side. Then, the registration number N is given to the input terminal, and the value (H (N)) obtained by the one-way hash function operation unit 84 is encrypted. In the latter case, the calculation of equation (2) is performed.

Vn = F (Ks, N) (1)

Vn = F (Ks, H (N)) (2)

By performing the above processing, the distribution data shown in FIG. 6 can be created. Next, a case where the digital information purchased by the user is used will be described. When the user gives a predetermined instruction to the control means 5 of the terminal device 2 using the input means 8 of the terminal device 2, the process according to the flowchart shown in FIG. 8 is performed.

The user first selects digital information to be used by using the input means 8 of the terminal device 2 (step S2).
1). The control unit 5 to which the selection information is supplied reads the format type 51, registration number authenticator 52, and registration number 53 of the selected digital information from the digital information storage unit 6 (step S22). Then, the format type 51 is determined (step S23). If the data of the format type 51 is “0” (step S23 → NO),
Since the format is such that the registration number and the information body do not overlap (see FIG. 6A), the process directly proceeds to step S25. If the data of the format type 51 is “1” (step S23 → YES), the file read position is set to only V bits because the registration number and the information body are in a format in which the information body is superimposed (see FIG. 6B). Return (step S24). Further, the information body is read (step S25). Then, the registration number 53 and the registration number authenticator 52 are transmitted to the information management center 1 (step S26).

In the authentication processing means 104 of the information management center 1, the received registration number (Nr) 53 and registration number authenticator (Vr) 5
The following processing is performed on the data No. 2 to check whether or not the registration number 53 has been illegally changed (step S2).
7). When formula (1) is used when creating distribution data, the selector 85 is set to the f side and the registration number Nr received at the input terminal is set.
Is calculated by the encryption function operation unit 83 using the encryption function F, and the output Vo is obtained. When formula (2) is used when creating the distribution data, the selector 85 is set to the e side, the received registration number Nr is given to the input terminal, and the encryption function operation unit 83 uses the encryption function F ) Is calculated to obtain the output Vo.

Vo = F (Ks, Nr) (3)

Vo = F (Ks, H (Nr)) (4)

Then, it is checked whether the registration number authenticator Vr matches the output Vo. If Vr ≠ Vo (Step S27 → N
O) Since the registration number 53 has been illegally changed, data indicating use prohibition is transmitted to the terminal device 2.
(Step S28). If Vr = Vo (step S27 → Y
ES), since it can be determined that the registration number 53 has not been illegally changed, the process proceeds to step S29. In step S29, it is checked whether the registration number Nr is registered in the use condition table. If not registered (Step S29 → N
O), the registration number Nr is considered to have been forged,
The data indicating the use prohibition is transmitted to the terminal device 2 (step S28).

If the registration number Nr is registered in the use condition table (step S29 → YES),
It is checked whether the period restriction flag is set to “1” (step S30). If the period limit flag is “0” (step S30 → NO), the process directly proceeds to step S32 because no period limit is set. If the period limit flag is set to "1" (step S30
(YES), it is confirmed that the current date and time is between the permission start date and time and the permission end date and time (step S31). If the current date and time is between the permission start date and time and the permission end date and time (step S31 → YES), the process proceeds to step S32.

In this step S31, when the permission start date and time or the permission end date and time are the predetermined initial values (the period restriction flag is "1"), it is considered that the items having the initial values satisfy the permission condition. That is, if the permission start date and time is the initial value, only the permission end date and time are checked, and if the current date and time is before the permission end date and time, the process proceeds to step S32. Similarly, if the permission end date is the initial value, only the permission start date and time is checked, and if the current date is after the permission start date and time, the process proceeds to step S32. If it is not within the permission period (step S31 → NO), the process proceeds to step S28, and data indicating use prohibition is transmitted to the terminal device 2.

In step S32, it is checked whether the number limit flag is set to "1". When the number-of-times restriction flag is “0” (step S32 → NO), there is no particular restriction on the number of times of use, and the process directly proceeds to step S35. If the count limit flag is set to “1” (step S32 →
YES), it is checked whether the number of usable times is larger than "0" (step S33). Then, when the usable number of times is “0” (step S33 → NO), the process proceeds to step S28, and data indicating use prohibition is transmitted to the terminal device 2. If the usable number is not "0", the usable number is reduced by 1 (step S34), and the process proceeds to step S35. Then, if it is confirmed that the use is legitimate, the data indicating the use permission is transmitted to the terminal device 2 (step S35).

The control means 5 of the terminal device 2 checks whether or not the data received from the information management center 1 via the communication line 3 and the communication means 4 is a use permission (step S36). If there is (step S36 → YES), the digital information main body is read out from the digital information storage means 6, processed according to the format of the digital information, and output to the output means 9 such as a display and a speaker (step S37). If the data received from the information management center 1 is prohibited, an error message to that effect is output to the output means 9 and the process is terminated (step S38). By performing processing in this way, you can register properly, use period,
Only a legitimate terminal device (user) who keeps the frequency limit can be given permission to use digital information.

[0050]

The digital information management system and the digital information management method of the present invention not only prevent unauthorized copying of digital information, but also use the digital information by limiting the period of use, the number of times of use, or both. It becomes possible. Strictly speaking, it is possible to copy digital information itself, but if the number of uses is limited, even if a user who has obtained digital information in a legitimate manner gives a copy of digital information to another user, However, since the number of times that the original user can use it is reduced by the number of times that another user who obtained the copy has used it, the original user suffers disadvantage, so such an action (copying digital information) Can be suppressed sufficiently.

When a legitimate user wants to use digital information at two places, for example, at home and at work, the digital information is copied to separate terminal devices and used legitimately at each terminal device. be able to. Even in this case, when the number of times of use is limited, the number of times of use is limited by the total number of times of use in each terminal device, so that the information provider is not damaged. Further, since all the use conditions and use conditions of the digital information are recorded and managed by the information management center, it becomes very difficult for the user of the terminal device to illegally change the information.

On the other hand, the user can purchase the product by setting the use period and the number of use in detail according to individual needs, so that there is no waste and a substantially lower price than in the case of selling out without setting these conditions. And the necessary information can be used as needed. In addition, since the digital information is stored in the terminal device and only the use permission information is transmitted to the terminal device, the digital information is not stored in the terminal device but is compared with the conventional method in which the digital information is downloaded from the center each time it is used.
There is an excellent effect that the communication cost is reduced and the waiting time when using is reduced.

Further, in the present invention, a registration number and a registration number authenticator unique to the digital information body are given by the information management center, and the registration number authenticator cannot be created without an encryption key known only to the information center. It is very difficult for a user to forge a registration number and use digital information illegally.

Further, the present invention does not require an encryption processing function in the terminal device, and does not store an encryption key in the terminal device. That is, there is no part that requires a complicated processing function and confidentiality in the terminal device. Accordingly, a computer having a general configuration can be configured as a terminal device without adding a special device to the terminal device, so that the cost of the terminal device is lower than before and more users can use the terminal device. . In addition, since a computer having a general configuration can be configured as a terminal device, the type of terminal device using digital information is not limited.
The user can use the digital information from a plurality of different terminal devices, and the user's convenience is improved.

Further, a part of the bit string of the registration number or the registration number authenticator is matched with a part of the bit string of the information body, and the matched part is stored in the terminal device by being superimposed and stored. It can respond to unauthorized modification.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing one embodiment of a digital information management system of the present invention.

FIG. 2 is a configuration diagram showing an example of a terminal device of the digital information management system of the present invention.

FIG. 3 is a configuration diagram showing an information management center.

FIG. 4 is a diagram for explaining a use condition table.

FIG. 5 is a flowchart illustrating a method of setting a use condition table.

FIG. 6 is a configuration diagram illustrating an example of a data format supplied to a terminal device.

FIG. 7 is a configuration diagram showing an example of an authentication processing unit of the information processing center of the present invention.

FIG. 8 is a flowchart illustrating a procedure for using digital information.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 information management center 2 terminal device 3 communication line 4 communication means (first communication means) 5 control means (first control means) 6 digital information storage means 8 input means 9 output means 101 communication means (second communication means) 102 control means (second control means) 103 use condition storage means 104 authentication processing means

Claims (7)

[Claims] 1. A digital information management system in which a terminal device and an information management center are connected via a communication line and manages digital information stored in the terminal device, wherein the terminal device includes: First communication means for communicating with a management center, digital information storage means for storing a registration number for identifying the digital information, a registration number authenticator, and the digital information body, and controlling a use procedure of the digital information The information management center is configured to perform communication with the terminal device; a use condition storage unit configured to store and store the registration number and its use condition; Digital information management comprising: authentication processing means for authenticating the registration number using an authenticator; and second control means for controlling the entire information management center. Stem. 2. A communication means for communicating with an information management center, a digital information storage means for storing a registration number for identifying digital information, a registration number authenticator and a digital information body, and a procedure for using the digital information. A terminal device, comprising: control means for controlling. 3. The registration number is set such that a bit string of a specific part of the registration number or an authenticator of the registration number matches a bit string of a specific part of the digital information body, and the digital information storage is performed. 3. The terminal device according to claim 2, wherein said matching bit strings are superposed and arranged. 4. A communication means for communicating with a terminal device, a use condition storage means for storing and storing a registration number and a use condition thereof, an authentication processing means for authenticating the registration number using the authenticator, An information management center comprising: control means for controlling each means. 5. The registration number is set such that a bit string of a specific part of the registration number or an authenticator of the registration number matches a bit string of a specific part of the digital information body. Information management center described in 4. 6. A digital information management method for managing digital information stored in a terminal device, wherein a registration number for identifying the digital information and a registration number authenticator are transmitted from the terminal device via a communication line. A first procedure for transmitting to the connected information management center, a second procedure for confirming the validity of the registration number received by the information management center using the registration number authenticator and an encryption key, A third procedure for checking whether the digital information corresponding to the registration number received at the information management center matches the use condition, and if the digital information matches the use condition at the information management center, Transmitting a data indicating use permission to the terminal device, and transmitting a data indicating use prohibition to the terminal device if the use condition is not met, Digital information management method characterized by comprising a fifth step to be able to use the digital information only when it receives the data indicating the use permission. 7. A method in which the registration number authenticator is a value obtained by encrypting the registration number or a value obtained by substituting the registration number into a one-way hash function with an encryption key of the information management center. The digital information management method according to claim 6.