Information distribution method and program

Abstract

To provide a configuration that enables further improvement in security of information such as data.SOLUTION: An information distribution method according to an embodiment of the present disclosure comprises causing a computer to perform data conversion of original information to generate k pieces of information, and placing n distribution pieces including the k pieces of information at p placement locations. The original information is restored using the k pieces of information and an order relationship assigned to the k pieces of information.SELECTED DRAWING: Figure 2B

Description

[Technical field]

[0001] The present invention relates to an information distribution method and a program for dividing original information such as data and distributing the information. [Background technology]

[0002] With the development of information and communication technology, unauthorized access to information is becoming more and more prevalent. As a result, various mechanisms for preventing information leakage have been proposed and put into practical use (for example, see Patent Document 1).

[0003] For example, secret sharing schemes are known. In the threshold scheme, which is one of the secret sharing schemes, secret information is distributed among multiple pieces of information, and the original secret information can be restored by collecting any a pieces of information from these pieces of information, but the original information cannot be known even if any a-1 pieces of information are collected.

[0004] Secret sharing also includes a data transformation technology called AONT (All-Or-Nothing Transform). In general, AONT is a technique in which multiple pieces of information are obtained by performing a certain operation on secret information, and if all pieces of information are available, the original information can be restored, but if even one piece of information is missing, the original information cannot be restored. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2018-110442 A Summary of the Invention [Problem to be solved by the invention]

[0006] In recent years, with the further development of information and communication technology, more and more information such as data is transmitted, received, or managed via networks, while damage caused by unauthorized access to such information is also increasing. The present disclosure aims to provide a configuration that enables further improvement in the security of information such as data. [Means for solving the problem]

[0007] In order to achieve the above object, one aspect of the present disclosure is to The computer Data-transforming the original information to generate k pieces of information; disposing n pieces of dispersion, each containing the k pieces of information, in p placement locations; having The original information is restored using the k pieces of information and the order relationship assigned to the k pieces of information. Information distribution method to provide.

[0008] Preferably, the p, the n, and the k are each an integer of 2 or more.

[0009] Preferably, p and n are equal.

[0010] Preferably, said generating includes scrambling said fragments of original information using at least said ordering relationship to generate said k pieces of information.

[0011] Preferably, the generating step includes secret sharing the original information by an AONT data conversion technique.

[0012] Preferably, said arranging includes creating said n pieces of distribution using said k pieces of information.

[0013] Preferably, said arranging includes creating said n pieces of distribution including said k pieces of information and dummy data.

[0014] Preferably, the sum of the number of the information pieces and the number of dummy data of a size corresponding to each information piece in the n number of scattering pieces is a multiple of the number of the scattering pieces.

[0015] Preferably, the placing step includes placing L of the n distribution pieces in L memory locations via a predetermined communication channel among two or more different communication channels, and placing distribution pieces other than the L of the n distribution pieces in (nL) memory locations via a channel other than the predetermined communication channel among the two or more communication channels.

[0016] The present disclosure also resides in a program for causing a computer to execute the above information distribution method. Effect of the Invention

[0017] According to the above aspect of the present disclosure, since the above configuration is provided, the security of information such as data can be further improved. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic configuration diagram of a system including an information processing device according to the first embodiment. [Figure 2A] FIG. 2A is a hardware configuration diagram of an information processing device. [Figure 2B] FIG. 2B is a block diagram showing a control configuration of the information processing device. [Figure 3A] FIG. 3A is a hardware configuration diagram of a terminal device. [Figure 3B] FIG. 3B is a block diagram showing a control configuration of the terminal device. [Figure 4] FIG. 4 is a flowchart of the information distribution process according to the first embodiment. [Figure 5A] FIG. 5A is an explanatory diagram illustrating an example of a flow of information distribution processing in the first embodiment. [Figure 5B] FIG. 5B is an explanatory diagram showing the flow of a process in a modified example of the process in FIG. 5A. [Figure 5C] FIG. 5C is an explanatory diagram showing a process flow in a further modified example. [Figure 6] FIG. 6 is a block diagram showing a control configuration of the information processing apparatus according to the second embodiment. [Figure 7] FIG. 7 is a flowchart of the information distribution process according to the second embodiment. [Figure 8] FIG. 8 is an explanatory diagram showing a part of the flow of information distribution processing in the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. The same components (or configurations) are denoted by the same reference characters, and have the same names and functions. Therefore, detailed description thereof will not be repeated.

[0020] Fig. 1 is a diagram showing the configuration of a system S including an information processing device 100 according to the first embodiment. Fig. 2A is a hardware configuration diagram of the information processing device 100, and Fig. 2B is a block diagram showing the control configuration of the information processing device 100.

[0021] The information processing device 100 functions as a part of the system S. The information processing device 100 includes a CPU 101, a Read Only Memory (ROM) 102, and a Random Access Memory (RAM) 103. In the information processing device 100, the CPU 101, the ROM 102, and the RAM 103 are connected via a bus 104. The bus 104 is further connected to a network interface 105 connected to a network N, an input interface 106 connected to an input unit 106a, a display interface 107 connected to a display unit 107a, and an external memory interface 108 connected to a storage medium 108a. The CPU 101 is also called a processor. However, the CPU 101 is not limited to a single processor, and may have a multiprocessor configuration. Also, a single CPU 101 connected by a single socket may have a multicore configuration. The input unit 106a is a keyboard and a mouse here, and may also include a touch panel integrated with the display unit 107a. The display unit 107a is a monitor here. The storage medium 108a is a hard disk drive, a solid state drive (SSD), etc. The CPU 101 executes a program stored in the storage medium 108a, for example, to provide various functions.

[0022] As shown in the block diagram of the information processing device 100 in FIG. 2B, the information processing device 100 having the above configuration includes a control unit 110, a communication unit 120, and a storage unit .

[0023] The control unit 110 is an example of a control means for controlling the operation of the information processing device 100. The control unit 110 is configured with a CPU 101, and executes information processing by a program. At least a part of the processing of each of the above units may be performed by a processor other than the CPU, for example, a dedicated processor such as a digital signal processor (DSP) or a graphics processing unit (GPU). At least a part of the processing of each of the above units may be an integrated circuit (IC) or other digital circuit. At least a part of each of the above units may include an analog circuit. The control unit 110 of the information processing device 100, i.e., the CPU 101, executes a computer program deployed in an executable manner in the information processing device 100, and provides various functions.

[0024] The communication unit 120 includes a network interface 105. The information processing device 100 can be connected to a network N such as the Internet via the communication unit 120 connected to the control unit 110, and can communicate bidirectionally with other devices, such as a terminal device 200 and a management device 300, via the network N. In FIG. 1, five management devices 300A to 300E are shown as the management devices 300, but this does not limit the number of management devices and is merely an example. Note that the terminal device 200 and the management device 300 are each a computer terminal and have the same configuration as the information processing device 100, and the names are merely for convenience and are not intended to limit the roles and / or functions, etc.

[0025] The storage unit 130 includes the ROM 102, the RAM 103, and a storage medium 108a. The storage unit 130 stores computer programs executed by the CPU of the control unit 110 and / or data, etc.

[0026] The control unit 110 includes, as functional modules, each of the functional modules of an information acquisition unit 1101, a pre-setting unit 1102, a generation processing unit 1103, a distributed processing unit 1104, a dummy processing unit 1105, and an arrangement processing unit 1106. Each functional module is realized by executing a program stored in the storage unit 130 by the control unit 110, that is, the CPU 101 of the control unit 110. However, some of the functional modules may be hardware such as other processors, digital circuits, or analog circuits. Each functional module can be referred to as a unit, a functional unit, or a means. The distributed processing unit 1104, the dummy processing unit 1105, and the arrangement processing unit 1106 are included in the distributed arrangement unit 1107, which is a functional module.

[0027] The information acquisition unit 1101 acquires various information from the network N via the communication unit 120, and acquires various information by communicating with, for example, the terminal device 200 and / or the management device 300. The information acquisition unit 1101 also stores the acquired information in the storage unit 130 according to the acquired information. Specifically, the information acquisition unit 1101 acquires pre-setting information from the terminal device 200 and sends it to the pre-setting unit 1102. Note that the pre-setting information includes at least any one of information that is set in advance and information that is the basis of the pre-set information. The information acquisition unit 1101 also acquires information to be managed through secret sharing (hereinafter, may be referred to as "original information") from the terminal device 200 and sends it to the generation processing unit 1103.

[0028] The pre-setting unit 1102 creates order data including an order relationship and dummy utilization information based on the pre-setting information sent from the information acquisition unit 1101, and stores the order data in the pre-data unit 1301 of the storage unit 130. In this storage, for example, storage associated with personal information, such as an ID, that identifies the user of the terminal device 200 is executed. The pre-data unit 1301 includes an order database 1301a and a dummy database 1301b, and may have them in a mutually related manner or may have them independently. For example, the pre-setting unit 1102 may generate an order relationship by performing a predetermined process on personal information such as an analysis of a pattern lock of the password of the terminal device 200 acquired via the terminal device 200 and an ID of the user of the terminal device 200. The pre-setting unit 1102 may store encryption processing data including an instruction for double encryption processing in the pre-data unit 1301. In addition, when the pre-setting unit 1102 acquires, as pre-setting information, sequence data including a predetermined sequence relationship and dummy utilization information, for example, via the terminal device 200 or via the input unit 106a of the information processing device 100, it stores them in the pre-data section 1301 of the memory unit 130.

[0029] The generation processing unit 1103 processes the information to be secretly shared, that is, the original information, sent from the information acquisition unit 1101 to generate pieces of information. In this embodiment, this processing includes data conversion of the original information. Here, a plurality of converted data fragments m (m1, . . . , mk) are created by the sharing processing. In the generation processing unit 1103, at least one converted data fragment m is created by secretly sharing the original information using the AONT data conversion technology, and more preferably, two or more, that is, a plurality of converted data fragments m1, m2, . . . are created, that is, k pieces of converted data fragments m are created. However, k is an integer of 1 or more, and preferably an integer of 2 or more. Each of the plurality of converted data fragments m (m1, . . . , mk) corresponds to the "piece of information" in the present invention. Note that the AONT data conversion technology is known, and therefore a description thereof will be omitted here. However, the present disclosure allows the use of a technology or method other than the AONT data conversion technology to data convert the original information.

[0030] The distributed placement unit 1107 executes placement of n distributed pieces M (M1,...,Mn) including converted data fragments m (m1,...,mk), which are k pieces of information generated by the generation processing unit 1103, at p placement locations. The distributed placement unit 1107 includes a distributed processing unit 1104, a dummy processing unit 1105, and a placement processing unit 1106. Note that p, n, and k may each be 1, but are preferably integers of 2 or more. Also, p and k may be the same value, but may be different values. Also, p and n may be the same value, but may be different values.

[0031] The distribution processing unit 1104 creates n distribution pieces M (M1, . . . , Mn) using k data fragments m (m1, . . . , mk) created by the generation processing unit 1103. This process corresponds to a process of distributing the data fragments m to the distribution pieces M. In other words, each distribution piece M is a kind of container, and the data fragments m are distributed to them or within them. The distribution piece M (M1, . . . , Mn) may simply include one of the data fragments m (m1, . . . , mk) created by the generation processing unit 1103, but may include a different number of data fragments m (m1, . . . , mk). For example, when there are 10 data fragments (k=10) created by the generation processing unit 1103 and there are 5 locations (p=5) for the data fragments, the number n of distribution pieces M can be set to 5, which is the same as the number p of locations, and each distribution piece M can be created as follows. As the shared pieces M, an "I" shared piece M1 including the first data fragment m1 and the second data fragment m2, a "II" shared piece M2 including the third data fragment m3 and the fourth data fragment m4, a "III" shared piece M3 including the fifth data fragment m5 and the sixth data fragment m6, an "IV" shared piece M4 including the seventh data fragment m7 and the eighth data fragment m8, and a "V" shared piece M5 including the ninth data fragment m9 and the tenth data fragment m10 may be generated. Such a method or process for creating multiple shared pieces M1 to M5 using multiple secretly shared data fragments m1 to m10 can be set arbitrarily, and is executed here by taking consecutive data fragments from the data fragments m1 to m10 and pairing them in pairs, but is not limited to this. How the data fragments m (m1, . . . mk) are combined to create the shared pieces M (M1, . . . Mn) is also specified in the above-mentioned order data.

[0032] In this way, the distributed processing unit 1104 distributes data fragment m (m1, m2, ..., mk), which is k pieces of information obtained by data conversion of the original information, into n pieces of distributed fragments M (M1, ..., Mn). However, as described above, "k" and "n" may each be "1", but are preferably integers of "2" or more. When there are two or more pieces of distributed fragments M (M1, ...), it is preferable that their data sizes are approximately equal. This makes it more difficult to identify differences between the pieces of distributed fragments M or to infer their characteristics.

[0033] The dummy processing unit 1105 creates dummy data. The dummy data is data that is not based on the original information and does not contribute to the restoration of the original information. Specifically, the dummy processing unit 1105 creates dummy data that may be included in the distributed pieces M (M1, . . . , Mn) created by the distributed processing unit 1104. The dummy data may be created based on the dummy utilization information stored in the dummy database 1301b of the pre-data unit 1301. For example, the dummy utilization information includes the presence or absence of utilization of dummy data, and here, in the management of the original information from the terminal device 200, the utilization of dummy data is set to "yes". Here, the dummy utilization information may be previously determined between the terminal device 200 and the information processing device 100, but may simply be set on the information processing device 100 side. The size of the dummy data may be set so that the sizes of the distributed pieces M are approximately equal to each other. This makes it difficult to distinguish the distributed pieces M. As will be understood from the description below, the size of the dummy data may have a size corresponding to each of the above-mentioned data fragments m, which are pieces of information, as a reference size. In this embodiment, the dummy processing unit 1105 functions according to the processing in the distributed processing unit 1104, but may also function according to the processing in the generation processing unit 1103. For example, when the unit of dummy data is a piece of dummy data (hereinafter, a dummy piece) having a size corresponding to each data fragment m generated by the generation processing unit 1103, the dummy processing unit 1105 creates dummy data so that the sum of the number k of data fragments m and the number q of dummy data, i.e., dummy pieces, is a multiple of the number n of distributed pieces M, that is, an integer multiple such as 1x, 2x, 3x, . . . In this way, the same number of data fragments m and / or dummy pieces can be arranged in each distributed piece M, so that the size of each data of the distributed piece M can be made approximately the same. By having the data size of each of the dispersion pieces M be approximately the same, it becomes more difficult for a third party to determine whether or not each dispersion piece M contains a data fragment m or a dummy piece.

[0034] The placement processing unit 1106 transmits the n distributed pieces M (M1, ..., Mn) created by the distributed processing unit 1104 via the communication unit 120 so that the n distributed pieces M are placed in p placement locations. At this time, when there is dummy data created by the dummy processing unit 1105, the dummy data is included in the corresponding distributed piece M (M1, ..., Mn) and constitutes a part or all of the corresponding distributed piece M. The decision of how to distribute and place the distributed pieces M (M1, ...) in each of the p placement locations is made based on the order relationship in the order database 1301a of the pre-data unit 1301.

[0035] Next, a description will be given of the terminal device 200. As shown in Fig. 1, the terminal device 200 functions as a part of the system S. Fig. 3A is a hardware configuration diagram of the terminal device 200, and Fig. 3B is a block diagram showing the control configuration of the terminal device 200.

[0036] The terminal device 200 includes a CPU 201, a ROM 202, and a RAM 203. In the terminal device 200, the CPU 201, the ROM 202, and the RAM 203 are connected via a bus 204. Furthermore, the bus 204 is connected to a network interface 205 connected to a network N, an input interface 206 connected to an input unit 206a, a display interface 207 connected to a display unit 207a, and an external memory interface 208 connected to a storage medium 208a. The CPU 201 is also called a processor. However, like the above-mentioned CPU 101, the CPU 201 is not limited to a single processor, and may be configured as a multiprocessor, for example. The input unit 206a here is a keyboard and a mouse, and may also include a touch panel integrated with the display unit 207a. The display unit 207a here is a monitor. The storage medium 208a is a hard disk drive, a solid state drive (SSD), or the like. The CPU 201 executes programs stored in, for example, the storage medium 208a to provide various functions.

[0037] As shown in the block diagram of the terminal device 200 in Fig. 3B, the terminal device 200 includes a control unit 210, a communication unit 220, and a storage unit 230. The control unit 210 corresponds to the above-mentioned control unit 110, the communication unit 220 corresponds to the above-mentioned communication unit 120, and the storage unit 230 corresponds to the above-mentioned storage unit 130. For example, the control unit 210 is an example of a control means that controls the operation of the terminal device 200, includes a CPU 201, and executes information processing by a program. The storage unit 230 includes a ROM 202, a RAM 203, and a storage medium 208a, and stores computer programs and / or data executed by the control unit 210, i.e., the CPU 201.

[0038] The control unit 210 includes, as functional modules, each of the functional modules of an information generating unit 2101, an information providing unit 2102, an instruction acquiring unit 2103, a sequence data creating unit 2104, and a restoration processing unit 2105. Each functional module is realized by executing a program stored in the storage unit 230 by the control unit 210, that is, by the CPU 201 of the control unit 210. However, some of the functional modules may be hardware such as other processors, digital circuits, or analog circuits. Each functional module can be referred to as a unit, a functional unit, or a means.

[0039] The information generating unit 2101 generates raw information. The raw information may be any information. Therefore, the information generating unit 2101 may be data, various software or application programs, and the terminal device 200 may be various devices including an in-vehicle device, a device of a work machine, and the like. The information generating unit 2101 may generate raw information by setting information acquired from a device other than the terminal device 200 as the raw information.

[0040] The information providing unit 2102 provides the original information generated by the information generating unit 2101 to the information processing device 100, that is, transmits it via the communication unit 220. The information providing unit 2102 may provide pre-setting information to the information processing device 100. Furthermore, when the information providing unit 2102 wants to restore the original information based on a user instruction acquired by the instruction acquiring unit 2103, it transmits a command to acquire a data fragment m of the original information to the information processing device 100 via the communication unit 220. Then, when the information providing unit 2102 acquires the data fragment m and the information for restoration, it transmits them to the restoration processing unit 2105. Note that the terminal device 200 may directly communicate with the management device 300 to exchange data and the like during the process of restoring the original information.

[0041] The instruction acquisition unit 2103 acquires a user instruction regarding the system S. Here, the user inputs the instruction via the input unit 206a of the terminal device 200. The instruction can be input by the user from an application that is activated by executing a program, or by accessing a website related to the information processing device 100. The instruction includes acquiring and analyzing information that is the basis of the preset information, and transmitting the information. When the instruction acquisition unit 2103 acquires information that is the basis of the preset information, the instruction acquisition unit 2103 transmits the information to the order data creation unit 2104. In addition, the instruction acquisition unit 2103 stores the order data created by the order data creation unit 2104 in the order database 2302 of the storage unit 230, and transmits the information to the information provision unit 2102. The information provision unit 2102 transmits the order data to the information processing device 100 via the communication unit 220. In addition, when the user does not wish, for example, the instruction acquisition unit 2103 may transmit information on which the preset information is based to the information processing device 100 via the communication unit 220 without going through the sequence data creation unit 2104. This makes it possible to avoid storing the sequence data itself in the terminal device 200, and therefore the security level can be further improved. In addition, the instruction acquisition unit 2103 can acquire an instruction to collect the shared pieces M managed by the secret sharing management in the system S to restore the original information, that is, a restoration instruction. When the instruction acquisition unit 2103 acquires the restoration instruction, it transmits the instruction to the information provision unit 2102 as described above, and also transmits the instruction to the restoration processing unit 2105. In addition, this instruction may include information for identifying the original information to be restored, such as the creation date and time of the original information, the type of the original information, and the like. In addition, the instruction acquisition unit 2103 acquires utilization information of the dummy data from the user, that is, dummy utilization information, stores it in the restoration database 2303 of the storage unit 230, and transmits the dummy utilization information to the information processing device 100 via the information provision unit 2102. For example, the instruction acquisition unit 2103 acquires information on whether or not the dummy data selected by the user is to be utilized, and transmits the information to the information processing device 100 via the information provision unit 2102 .

[0042] The sequence data creation unit 2104 creates sequence data. In creating this sequence data, for example, the pattern lock input from the input unit 206a is analyzed. For example, the sequence data creation unit 2104 divides the touch panel of the display unit 207a into nine parts, and assigns numbers 1 to 9 to the nine divided squares to display a pattern lock screen. When the user traces the numbers on this pattern lock screen in order with his / her finger, the user can input a multi-digit pattern lock number sequence consisting of numbers 1 to 9. The user can create sequence data from this pattern lock number sequence. This sequence data is used for the order relationship of the distributed pieces M, and is therefore also used for the order relationship of the data fragments m arranged on the distributed pieces M.

[0043] The restoration processing unit 2105, upon receiving an instruction to restore from the instruction acquisition unit 2103 and receiving the distributed pieces M and information for restoration from the information provision unit 2102, restores the original information using the AONT data conversion technology. The restoration processing unit 2105 extracts all data fragments m from the distributed pieces M. At this time, information for restoration including the order relationship of the distributed pieces M is used. Then, based on the order relationship given to the extracted data fragments m, the restoration processing unit 2105 restores the original information. Since the AONT data conversion technology is particularly used here, it is more clear that the original information is restored from all of the k data fragments, that is, the k data fragments m, and the order relationship given to the k data fragments m. The information for restoration may be set in advance and stored in the restoration database 2303 of the storage unit 230, that is, the terminal device 200 does not need to transmit or receive the information between the terminal device 200 and another device (for example, the information processing device 100). This can further improve the security level. The restoration information can include information such as the order relationship of the distribution pieces M, the arrangement of the data fragments m in the distribution pieces M, the order relationship given to the k data fragments m, and dummy utilization information.

[0044] As shown in FIG. 1, the management device 300 constitutes a part of the system S. Here, the management device 300 has the same configuration as the information processing device 100 described above, and functions as a storage location for storing the distributed pieces M, that is, a storage device. The management device 300 stores the distributed pieces M transmitted from the information processing device 100 in its storage unit, and can provide the distributed pieces M stored in the storage unit to the terminal device 200 via or without the information processing device 100 in response to a command from the information processing device 100 or the terminal device 200. The storage of the distributed pieces M is performed by an information storage unit, which is a functional module of the control unit of the management device 300, and the provision of the distributed pieces M is performed by an information provision unit, which is a functional module of the control unit of the management device 300.

[0045] Fig. 4 is a flowchart of the information sharing process of the first embodiment. Secret sharing management of certain original information will be described, focusing on the process in the control unit 110 of the information processing device 100 in the system S having the above configuration. Note that the flowchart in Fig. 4 is preferably repeated at a predetermined time interval or irregularly.

[0046] First, the order relationship such as the order data and the dummy utilization information are stored in the storage unit 230 of the terminal device 200 and the storage unit 130 of the information processing device 100, respectively (S401 in FIG. 4). This is performed in advance by the instruction acquisition unit 2103, the order data creation unit 2104, and the information provision unit 2102 of the terminal device 200, and in cooperation with the pre-setting unit 1102 of the information processing device 100, when preparing the pre-setting information. Note that this preparation of the pre-setting information may be performed by the user of the terminal device 200 and / or the user of the information processing device 100 without going through the network N, and at least one of storing all or a part of the pre-setting information in the storage unit 230 of the terminal device 200 and storing it in the storage unit 130 of the information processing device 100 may be performed. All or a part of the pre-setting information may not be stored at all in both the storage unit 230 of the terminal device 200 and the storage unit 130 of the information processing device 100. In this case, all or a part of the pre-setting information may be designated by the user. This can further improve the security level. Here, the order relationship is determined such that the "first distributed piece M1" is linked to the "second management device 300B", the "second distributed piece M2" is linked to the "fifth management device 300E", the "third distributed piece M3" is linked to the "first management device 300A", the "fourth distributed piece M4" is linked to the "third management device 300C", and the "fifth distributed piece M5" is linked to the "fourth management device 300D". When only one data fragment m is associated with one distributed piece M, this order relationship is the order relationship of the k data fragments m. Here, since multiple data fragments m can be associated with one distributed piece M, the order relationship is determined such that the data fragments m generated by the generation processing unit 1103 are sequentially arranged on the distributed piece M. The order relationship of arranging the data fragments m on the distributed piece M will be described later with reference to FIG. 5A and FIG. 5B.

[0047] The raw information generated by the terminal device 200 is provided to the information processing device 100 (S403). The raw information is provided by the information providing unit 2102. When the information acquiring unit 1101 of the information processing device 100 acquires the raw information (S405), it transmits the raw information to the generation processing unit 1103.

[0048] As a result, the generating unit 1103 processes the original information to generate k data fragments m (S407). As described above, the generating unit 1103 uses the AONT data conversion technique to convert the original information and perform secret sharing. Depending on the size of the original information, it is assumed here that the original information is converted into eight converted data fragments m1 to m8.

[0049] Then, the distributed processing unit 1104 creates a distribution piece M using the generated converted data fragment m (S409). First, a previously set order relationship is read here. When reading this order relationship, dummy utilization information is also read. Note that the timing of reading the pre-setting information is not limited to the timing immediately after step S407, and may be when the original information is acquired from the terminal device 200, for example. In this example, there are five management devices 300, and the number of converted data fragments m1 to m8 is eight. Therefore, the distributed processing unit 1104 creates five distribution pieces M1 to M5 using the eight converted data fragments m1 to m8 (S409). Here, it is specified that the converted data fragments m1 to m8 are stored in the distribution fragments M1 to M5 in order, two at a time if possible, so the distribution fragments M1 to M4 are created using the converted data fragments m1 to m8, and the remaining distribution fragment M5 is left blank, that is, in a blank state. Note that it is desirable that the sizes of the four distribution fragments M1 to M4 are approximately the same. Since the data sizes of the distributed pieces M are approximately the same, it becomes difficult to infer the characteristics of each distributed piece M, thereby improving the security level.

[0050] Here, there are five management devices 300, and each management device 300 is defined as one installation location, that is, one storage location. However, each management device 300 may be provided with multiple installation locations. At this time, one distribution piece M is associated with each placement location, so the number of distribution pieces M is set to 5. The number of converted data fragments m is 8, which is more than the number of distribution pieces M (5), but is less than 10, which is twice the number of distribution pieces M. Therefore, two data fragments are distributed to each distribution piece M. Then, the area of ​​the distribution piece where the data fragment is insufficient is left blank. For example, the number of converted data fragments m is 13, the number of distribution pieces is 5, and the rule that four data fragments are distributed to each distribution piece when possible is applied is shown below. In this case, four data fragments are assigned to each of the distribution pieces M1 to M3, one data fragment is assigned to the distribution piece M4, and a blank of a size equivalent to three data fragments is generated, and a blank of a size equivalent to four data fragments is generated in the distribution piece M5.

[0051] Then, the necessity of creating dummy data is determined (S411). Specifically, it is determined here whether there is a distributed piece to be filled with dummy data among the distributed pieces M (M1, . . .) created by the distributed processing unit 1104. Here, since an instruction for using dummy data is stored in advance and there is a distributed piece M5 to be filled with dummy data (positive determination in S411), dummy data is created (S413). Here, dummy data that fills the entire distributed piece M5 is created. This dummy data is created so that the size of the distributed piece M5 is approximately equal to each size of the other distributed pieces M1 to M4, more preferably so that they are equal. Note that when the creation of dummy data is unnecessary, for example, when the number k of the converted data fragments m is equal to the number p of the arrangement locations, the creation of dummy data is unnecessary (negative determination in S411), so the process proceeds to step S415 without going through step S413.

[0052] Then, based on the read-in predetermined order relationship, the five distributed pieces M1 to M5 are distributed to the management devices 300 (300A to 300E) by the distribution processing unit 1106 (S415). The distributed pieces M1 to M5 are acquired by the corresponding management devices 300 and stored in the storage units thereof (S417). Note that the hardware configuration of the management device 300 is generally the same as the hardware configuration of the terminal device 200 shown in FIG. 3A, so further description here is omitted.

[0053] Here, the above process flow and state changes will be further explained based on Fig. 5A. Note that in Fig. 5A, time passes, processes are performed, and states change from top to bottom.

[0054] In the information processing device 100, the original information acquired by the information acquisition unit 1101 is processed by the generation processing unit 1103, and a data fragment m, which is an information piece, is generated (S407). In the AONT data conversion technology, the size of the fragment of the original information (i.e., plain text) to be subjected to data conversion is determined, and a converted data fragment m of the same size is generated. Here, as described above, it is assumed that eight converted data fragments m1 to m8 are generated by the AONT data conversion technology.

[0055] Then, the distribution processing unit 1104 creates distribution pieces M1 to M5 for distribution arrangement based on preset information such as order relationship (S409). As shown in Fig. 5A, here, the distribution piece M1 is a data piece obtained by connecting converted data fragments m1 and m2 in series, the distribution piece M2 is a data piece obtained by connecting converted data fragments m3 and m4 in series, the distribution piece M3 is a data piece obtained by connecting converted data fragments m5 and m6 in series, the distribution piece M4 is a data piece obtained by connecting converted data fragments m7 and m8 in series, and the distribution piece M5 is a blank. And, the distribution pieces M1 to M4 without blanks have, for example, approximately the same size as already described.

[0056] Then, the dummy processing unit 1105 creates dummy data for the dispersion piece M5 with a blank (S413). The dummy data is created so that the dispersion piece M5 has approximately the same size as each of the dispersion pieces M1 to M4. For example, the dummy data is a random sequence of numbers. In FIG. 5A, the dispersion piece M5 is shown to include a combination of two dummy data d1 and d2. In this case, each dummy data d1 and d2 has a size corresponding to each data fragment m in the dispersion pieces M1 to M4, that is, has approximately the same size as the size of each data fragment m, so that the dispersion pieces M1 to M5 have approximately the same size.

[0057] Then, the pieces M1 to M5 including the dummy data are distributed and arranged based on the preset information (S415). That is, the "first piece M1" is arranged in the "second management device 300B", the "second piece M2" is arranged in the "fifth management device 300E", the "third piece M3" is arranged in the "first management device 300A", the "fourth piece" is arranged in the "third management device 300C", and the "fifth piece M5" is arranged in the "fourth management device 300D".

[0058] In the first embodiment, for example, one distributed piece M1 is created by combining the converted data fragment m1 and the subsequent converted data fragment m2, but the distributed piece M for distributed placement may be created by combining the converted data fragment m1 and a separate data fragment such as the converted data fragment m5. This makes it even more difficult for a third party to recover the original information from the distributed piece M for distributed placement, since the data fragment m is randomly placed in the distributed piece M.

[0059] FIG. 5B shows a modified example of the above process shown in FIG. 5A. In the process shown in FIG. 5B, when data fragment m is generated in step S407, data fragments m1 to m8 are repeatedly assigned to the fragments M1 to M5 one by one in order in step S409. Therefore, in this case, the fragment M1 is composed of data fragment m1 and data fragment m6, the fragment M2 is composed of data fragment m2 and data fragment m7, the fragment M3 is composed of data fragment m3 and data fragment m8, and the fragments M4 and M5 include data fragments m4 and m5, respectively. Then, dummy data d3 is generated and incorporated in the blank portion of the fragment M4, and similarly, dummy data d4 is generated and incorporated in the blank portion of the fragment M5 (S413). In other respects, the process of FIG. 5B is the same as the process of FIG. 5A, so further explanation will be omitted.

[0060] In both the process of FIG. 5A and the process of FIG. 5B, the sum of the number k of information pieces, i.e., data fragments m, and the number q of dummy data of a size corresponding to each data fragment, in n pieces of distributed pieces M, is a multiple of the number n of distributed pieces. In the process of FIG. 5A, the number k of data fragments m is "8", the number q of dummy data of a size corresponding to each data fragment m is "2", and the sum (=k+q) is "10". This is the same as in the process of FIG. 5B. And, since the number n of distributed pieces is "5" here, this sum "10" is twice the number n of distributed pieces. In this way, by making the sum of the number k of information pieces, i.e., data fragments m, having approximately the same size, and the number q of dummy data of a size corresponding to each data fragment m (i.e., approximately the same size) in the distributed pieces M to be distributed and arranged, a multiple (integer multiple of 1 or more) of the number n of distributed pieces, the size of the distributed pieces M can be made approximately the same. Therefore, the size of the dispersion pieces M is approximately the same, so that processing such as statistical analysis of the dispersion pieces is performed to estimate the characteristics of the dispersion pieces M and to make processing such as discrimination more difficult. Note that here, the number n of dispersion pieces and the number p of placement locations are equal. Therefore, the sum of the number k of information pieces, i.e., data fragments m, and the number q of dummy data of a size corresponding to each data fragment in n dispersion pieces M is also a multiple of the number p of placement locations. However, this disclosure does not exclude the number n of dispersion pieces M and the number p of placement locations being different.

[0061] In both the process of FIG. 5A and the process of FIG. 5B, the sum of the number k of information pieces, i.e., data fragments m, and the number q of dummy data of a size corresponding to each data fragment in n pieces of distributed pieces M is a multiple of the number n of distributed pieces. Based on this relationship, it is also possible to execute the dummy data creation process in steps S411 and S413 before the distribution process in step S409. This case will be described based on FIG. 5C. Note that the process of FIG. 5C corresponds to a modified example of the process of FIG. 5A, and in the process of FIG. 5C, step S407 is followed by step S411, step S413, step S409, and step S415 in order.

[0062] In the process shown in FIG. 5C, when data fragments m are generated in step S407, the necessity of creating dummy data is determined in step S411. When the number k of data fragments m is an integer multiple of the number p of placement locations, i.e., the number n of distributed pieces, there is no necessity of creating dummy data (negative determination in S411), but when the number k of data fragments m is not an integer multiple of the number p of placement locations, i.e., the number n of distributed pieces, it is determined that there is a necessity of creating dummy data (positive determination in S411). Here, as described above, the number of data fragments m is "8" and the number of distributed pieces is set to the number of placement locations, "5", so that it is determined that there is a necessity of creating dummy data. As a result, in step S413, dummy data is created so that the sum of the number k of data fragments m and the number q of dummy data of a size corresponding to each data fragment m (i.e., approximately the same size) is a multiple (1x, 2x, 3x, . . .) of the number p of placement locations, i.e., the number n of distributed pieces. As a result, dummy data d1 and d2 of approximately the same size as each data fragment m are created as described above. Here, the multiple of the number n of dispersed pieces is set each time so that the number of dummy data to be created is reduced, but the present disclosure is not limited to this. Then, when dummy data is created (S413) or it is determined that there is no need to create dummy data (negative determination in S411), the dispersion process of step S409 is executed to create dispersed pieces M. In the process of FIG. 5C, data fragments m1 to m8 and dummy data d1 and d2 are arranged in order, and dispersed pieces M1 to M5 are created (S409) as in the case of FIG. 5A, and the dispersed arrangement process of these dispersed pieces M1 to M5 is executed (S415). Note that the creation process of dummy data (S411 and S413) before the creation of dispersed pieces M (S409) can be similarly applied to the case of FIG. 5B and the case of the second embodiment described later.

[0063] In addition, the converted data fragment m may be further simply divided and used to create the shared fragment M. This makes it more difficult for a third party to generate the converted data fragment m from the shared fragment M. Furthermore, the order of the fragments (plain text) of the original information may be scrambled and rearranged, and then the AONT data conversion technology may be applied to create k data fragments. This makes it possible to further increase the difficulty of restoring the original information. In this case, the scrambling may be performed based on a predetermined order relationship, that is, a predetermined order relationship for plain text. This order relationship may be associated with the shared fragment M, stored in the restoration database 2303, or provided to the restoration processing unit 2105. In this embodiment, the restoration processing unit 2105 is provided in the terminal device 200, but may also be provided in the information processing device 100.

[0064] As described above, according to the information distribution method by the information processing device 100 of the above-mentioned system S (see particularly FIG. 4, FIG. 5A, FIG. 5B, or FIG. 5C), not only is the AONT data conversion technology used, but also the distributed pieces M are distributed and placed in the management device 300 based on the order relationship given to the distributed pieces M for distribution. Therefore, the security level of information can be improved.

[0065] Furthermore, instead of simply creating the distributed piece M from the data fragment m, dummy data can also be used for the distributed piece M. Therefore, even if the distributed piece M is stolen, it becomes more difficult to restore the original information from it, and it is possible to further improve the security level of the information. In addition, the location of the dummy data can be determined arbitrarily. Therefore, the security level can be further improved.

[0066] In the first embodiment, one distributed piece M is paired and distributed in one management device 300, but multiple distributed pieces M may be distributed in one management device 300 and stored independently in the memory unit.

[0067] Next, a second embodiment will be described. In the following, differences between the second embodiment and the first embodiment will be mainly described. The same reference numerals as those already used are used to designate the components and steps already described, and duplicated explanations will be omitted.

[0068] 6 shows a block diagram of the information processing device 100. In the information processing device 100, a double encryption database 1301c is stored in addition to a sequence database 1301a and a dummy database 1301b in a pre-data section 1301 of a storage section 130. When an instruction acquisition section 2103 of a terminal device 200 receives an instruction from a user to increase the security level, the instruction is transmitted to the information processing device 100 via an information provision section 2102.

[0069] In the information processing device 100, when the information acquisition unit 1101 acquires an instruction from a user to increase the security level, the information acquisition unit 1101 stores the instruction information of "increase the security level" in the double encryption database 1301c of the storage unit 130 together with personal information, such as an ID, that identifies the user of the terminal device 200. As a result, when acquiring original information from the terminal device 200, the control unit 110 of the information processing device 100 executes double encryption processing, which is the processing of "increase the security level." By making it possible to receive an instruction to "increase the security level," it is possible to assign a level of importance to the original information, and it is possible to expand the scope of application of the information distribution method of the present disclosure.

[0070] In the AONT data conversion technology, the index is applied to an encryption machine using a secret key, and the plain text, which is an information piece of the original information, is XORed (eXclusive ORed) to generate the data fragment m after the conversion process. The index is generally a simple order, but the index is rearranged based on the order relationship of the preset information. For example, since the order relationship is determined such that the "first shared piece M1" is linked to the "second management device 300B", the "second shared piece M2" is linked to the "fifth management device 300E", the "third shared piece M3" is linked to the "first management device 300A", the "fourth shared piece M4" is linked to the "third management device 300C", and the "fifth shared piece M5" is linked to the "fourth management device 300D", the first index is set to "3", the second index to "1", the third index to "4", the fourth index to "5", and the fifth index to "2", a double encryption process is performed. This makes it possible to increase the security level compared to when the index is not changed. In this case, the index information corresponds to the order relationship of the pre-configuration information, but the index information may be set separately from the order relationship of the pre-configuration information and stored in at least one of the terminal device 200 and the information processing device 100. In this case, the index information is preferably included in the pre-configuration information. This double encryption process can also be defined as "processing of changing the index".

[0071] The information distribution processing in the second embodiment will be described with reference to FIGS.

[0072] When the information acquisition unit 1101 of the control unit 110 of the information processing device 100 acquires the original information provided by the terminal device 200 (S403, S405), it sends the original information to the generation processing unit 1103. Since the original information is accompanied by personal information that identifies the user of the terminal device 200, the generation processing unit 1103 searches the pre-data unit 1301 of the storage unit 130 for the personal information and acquires an execution instruction for double encryption processing corresponding to the personal information. This allows the generation processing unit 1103 to acquire an execution instruction for double encryption processing, which is a "security level up" process corresponding to the personal information, from the double encryption database 1301c, and therefore executes the above-mentioned double encryption processing (S701).

[0073] Then, in a state where the double encryption process has been executed, the generation processing unit 1103 performs the generation process of the data fragment m (S407). The subsequent steps S409 to S417 have already been explained, so the explanation here (including the illustration in FIG. 8) will be omitted.

[0074] In this way, by performing encryption processing in more stages using a predetermined order relationship, it is possible to further improve the security level.

[0075] Although the embodiment and its modified examples according to the present invention have been described above, the present invention is not limited thereto. Various substitutions and modifications are possible without departing from the spirit and scope of the present invention defined by the claims of this application. The processes and means described in this disclosure can be freely combined and implemented as long as no technical contradiction occurs.

[0076] For example, in the above embodiment, the distribution pieces M are arranged via one network N. However, it may be arranged via multiple communication channels. It is also possible to arrange L distribution pieces out of n distribution pieces in L memory locations via a predetermined communication channel out of two or more different communication channels, and arrange distribution pieces other than the L distribution pieces out of n distribution pieces in (nL) memory locations via a channel other than the predetermined communication channel out of two or more communication channels. This makes it possible to better prevent the extraction of information, i.e., data fragments, by changing the communication channel. [Explanation of symbols]

[0077] S System 100 Information processing device 110 Control section 120 Communications Department 130 Storage section 200 Terminal Equipment 210 Control section 220 Communications Department 230 Storage section 300, 300A~300E management device

Claims

[Claim 1] In an AONT secret sharing system including a terminal device, an information processing device, and a plurality of management devices, The terminal device an information generating unit that generates raw information; An instruction acquisition unit that acquires a pattern lock sequence, which is an instruction from a user, via an input unit; a sequence data generating unit for generating sequence data based on the acquired sequence; an information providing unit that provides the original information, dummy utilization information indicating whether or not dummy data is utilized, and pre-setting information including the order data to the information processing device via a network; The information processing device includes: an information acquisition unit that acquires the original information and the pre-setting information from the terminal device; A pre-setting unit that stores the pre-setting information in a storage unit; A generation processing unit converts the original information into k pieces of information using an AONT data conversion technique; a dummy processing unit that generates the dummy data when the dummy utilization information indicates utilization; a distribution arrangement unit that arranges n pieces of distributed data, each of which includes the k pieces of information and the dummy data, in the management device, which is p pieces of distribution locations, based on the order data; The AONT secret sharing system has:

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