JP2019096987A - Block chain generation system, block chain generation method, and block chain generation program - Google Patents

Abstract

To provide a block chain generation device which facilitates management of multiple block chains.SOLUTION: A block chain generation device 100 acquires a first hash value set to the up-to-date block 112 of a block chain 110. The block chain generation device 100 receives a second hash value, set to the up-to-date block 122 of a block chain 120 managed by other device, from other device. The block chain generation device 100 adds an intermediate block 113, having the acquired first hash value and the received second hash value, to the block chain 110. The block chain generation device 100 adds a block 114, having a third hash value common to the block chains 110, 120, to the block chain 110 by using a given function.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a block chain generation system, a block chain generation method, and a block chain generation program.

  2. Description of the Related Art Conventionally, there is a technique of creating a block in which data is grouped at a certain time interval, and linking the generated blocks to create a list called a block chain that manages data. The block chain is generated, for example, for every organization, and one or more nodes in any organization store the same block chain in common.

  As prior art, for example, when payment of the value of the virtual currency required for use of the content can be confirmed from the transaction data input to the P2P virtual currency network by the client terminal, the use of the content is made available to the user of the client terminal. There is something to allow. Also, for example, there is a technique of detecting transaction events in an online transaction, and recording transaction information associated with each of the transaction events. Also, for example, there is a technique for verifying the legitimacy of the second transaction in which the first user remits at least a portion of the amount of money transferred in the first transaction in which the virtual currency is remitted to the first user.

JP, 2016-162431, A JP, 2016-151802, A JP, 2016-200954, A

  However, in the prior art, when a plurality of organizations merge, it is difficult to manage the block chain generated in each organization according to the state of the plurality of organizations after the merger. For example, when a plurality of organizations merge, it is conceivable that block chains in each organization are collectively managed by a predetermined application, but it is costly to introduce an application, and the application may be a security vulnerability. .

  In one aspect, the present invention aims to provide a block chain generation system, a block chain generation method, and a block chain generation program capable of facilitating management of a plurality of block chains.

  According to one embodiment, the first block chain of the first block chain and the second block chain connecting one or more blocks corresponds to the latest block of the first block chain. Adding an intermediate block having a first hash value and a second hash value corresponding to the latest block of the second block chain, and the intermediate block added to the first block chain includes: The first block chain is calculated using a function capable of calculating a third hash value common to the first and second block chains based on the first hash value and the second hash value. , A block chain generation system for adding a block having the third hash value, a block chain generation method, and a block chain Formation program is proposed.

  According to one aspect, it is possible to facilitate management of a plurality of block chains.

FIG. 1 is an explanatory view showing an example of a block chain generation method according to the embodiment. FIG. 2 is an explanatory view showing an example of the block chain generation system 200. As shown in FIG. FIG. 3 is a block diagram showing an example of the hardware configuration of the block chain generation device 100. As shown in FIG. FIG. 4 is an explanatory diagram of an example of the storage content of the block 400. As shown in FIG. FIG. 5 is a block diagram showing an example of a functional configuration of the block chain generation device 100. As shown in FIG. FIG. 6 is a block diagram showing a functional configuration example of the block chain generation system 200. As shown in FIG. FIG. 7 is an explanatory diagram (part 1) of an operation example 1 of the block chain generation device 100. FIG. 8 is an explanatory view (part two) of an operation example 1 of the block chain generation device 100. FIG. 9 is an explanatory diagram (part 3) of an operation example 1 of the block chain generation device 100. FIG. 10 is an explanatory diagram (part four) of an operation example 1 of the block chain generation device 100. FIG. 11 is an explanatory diagram (part 5) of an operation example 1 of the block chain generation device 100. FIG. 12 is an explanatory diagram (part 6) of an operation example 1 of the block chain generation device 100. FIG. 13 is an explanatory diagram (part 7) of an operation example 1 of the block chain generation device 100. FIG. 14 is an explanatory diagram (part 8) of an operation example 1 of the block chain generation device 100. FIG. 15 is an explanatory diagram (No. 9) showing an operation example 1 of the block chain generation device 100. FIG. 16 is an explanatory diagram (part 10) of an operation example 1 of the block chain generation device 100. FIG. 17 is an explanatory diagram (part 11) of an operation example 1 of the block chain generation device 100. FIG. 18 is an explanatory diagram (part 12) of an operation example 1 of the block chain generation device 100. FIG. 19 is a flowchart of an example of a block chain management process procedure according to the first operation example. FIG. 20 is an explanatory diagram of an operation example 2 of the block chain generation device 100. FIG. 21 is an explanatory diagram (part 1) of an operation example 3 of the block chain generation device 100. FIG. 22 is an explanatory diagram (part two) of an operation example 3 of the block chain generation device 100. FIG. 23 is a flowchart of an example of a block chain management process procedure according to the third operation example.

  Hereinafter, embodiments of a block chain generation system, a block chain generation method, and a block chain generation program according to the present invention will be described in detail with reference to the drawings.

(One Example of Block Chain Generation Method According to Embodiment)
FIG. 1 is an explanatory view showing an example of a block chain generation method according to the embodiment. The block chain generation device 100 is a computer that manages block chains.

  A block chain is a list for managing data. A block chain is a linked list of one or more blocks. The block chain is generated and stored, for example, in some organization. One or more nodes in any organization store and manage the same block chain in common. A block is a data set that combines one or more pieces of data.

  Here, in a situation where block chains are stored in each organization of a plurality of organizations, it may be attempted to merge a plurality of organizations. In this case, it is desirable to manage block chains in each organization so as to match the state of multiple organizations after merger.

  For example, after a plurality of organizations merge, there is a demand to manage block chains generated in each organization so that the same block is added to block chains in each organization. In other words, after a plurality of organizations merge, there is a demand to make the block chain in each organization common among the organizations.

  On the other hand, there is a demand for blocks that have been added to a block chain in one organization prior to the merger of multiple organizations to be prevented from being referenced by other organizations even after the merger of the multiple organizations. is there. However, it is difficult to manage block chains in each organization so as to meet the above-mentioned needs in accordance with the state of multiple organizations after merger.

  For example, when a plurality of organizations merge, it is conceivable that a block chain in each organization is monitored by a predetermined application and collectively managed by the predetermined application. In this case, it is costly to introduce and operate the application, and the application may be a security vulnerability.

  Specifically, a predetermined application will manage the restriction of access from each organization with respect to the block added to the block chain before the plurality of organizations merge. Also, a given application will guarantee the legitimacy of the block upon merger. For this reason, it is preferable to strengthen the security of a predetermined application, which leads to an increase in the cost of operating the predetermined application.

  Therefore, in the present embodiment, a block chain generation method capable of causing the same block to be added to the block chain in each organization after a predetermined timing by using a block chain mechanism. explain. According to this, the block chain generation method can make it easy to manage the block chain in each organization according to the state of a plurality of organizations after the merger.

  In the example of FIG. 1, block chains are stored in two organizations. Specifically, in the organization A, the block chain 110 is stored. The block chain 110 includes blocks 111 and 112. In the organization B, a block chain 120 is stored. The block chain 120 includes blocks 121 and 122.

  One or more block chain generation devices 100 are included for each tissue. The block chain generation device 100 manages block chains in any organization as nodes in any organization. In the following description, the block chain generation device 100 manages the block chain 110 in the organization A as a node in the organization A.

  The block chain generation device 100 acquires a first hash value corresponding to the latest block of the block chain managed by the own device. The first hash value corresponding to the latest block is, for example, a hash value indicating the latest block, which is calculated by substituting the latest block into a predetermined function. The first hash value corresponding to the latest block may be, for example, a hash value obtained by copying the hash value set for the latest block. The block chain generation device 100 acquires, for example, the first hash value set in the latest block 112 of the block chain 110.

  Also, the block chain generation device 100 acquires a second hash value corresponding to the latest block of the block chain managed by another device other than the block chain managed by the own device. The second hash value corresponding to the latest block is, for example, a hash value indicating the latest block, which is calculated by substituting the latest block into a predetermined function. The second hash value corresponding to the latest block may be, for example, a hash value obtained by copying the hash value set for the latest block. The block chain generation device 100 receives, for example, the second hash value set in the latest block 122 of the block chain 120 from the other device.

  Then, the block chain generation device 100 adds an intermediate block having the first hash value and the second hash value to the block chain managed by the own device. The block chain generation device 100 adds, for example, an intermediate block 113 having the acquired first hash value and the received second hash value for the block chain 110. On the other hand, the other device similarly adds an intermediate block 123 for the block chain 120.

  Next, the block chain generation device 100 uses the predetermined function based on the first hash value and the second hash value of the intermediate block added to the block chain managed by the own device, using the third function. Calculate the hash value. The predetermined function is a function capable of calculating a third hash value common to a plurality of block chains.

  Then, the block chain generation device 100 adds a block having the third hash value to the block chain managed by the own device. The block chain generation device 100 adds a block 114 having a third hash value common to the block chains 110 and 120, for example, for the block chain 110. On the other hand, the other device similarly adds, for the block chain 120, a block 124 having a third hash value common to the block chains 110 and 120.

  Thereby, the block chain generation device 100 may add an intermediate block to the block chain managed by the own device so that the third hash value common to the plurality of block chains is calculated by the predetermined function. it can. Then, the block chain generation device 100 can add a block having a third hash value common to a plurality of block chains to the block chain managed by the own device. As a result, in each block chain, the block added next to the intermediate block will match.

  Therefore, in the following, the same block is added to each block chain, and the block chain generation device 100 shares a plurality of block chains among organizations using the block chain mechanism. can do. In this manner, the block chain generation device 100 can manage block chains managed by the own device so as to match the state of a plurality of merged organizations. In addition, the block chain generation device 100 can guarantee the consistency of the blocks before and after the merger by using the block chain mechanism.

  The block chain generation device 100 can leave special blocks, such as an intermediate block and a block following an intermediate block generated based on the intermediate block, for a block chain managed by the own device. For this reason, the block chain generation device 100 can make it possible to determine later the timing when the block chain managed by the own device is shared.

  On the other hand, the block chain generation device 100 may store the block added before the intermediate block in the block chain managed by the own device by the own device, even if other devices do not refer to it. Good. For this reason, the block chain generation device 100 can protect the transaction information, personal information, confidential information, and the like included in the block added before the intermediate block in the block chain managed by the own device. Security can be improved.

  Further, the block chain generation device 100 may not introduce an application for managing each block chain, and can suppress an increase in human or financial cost due to the introduction or operation of the application. In addition, the block chain generation device 100 can improve security because the application is not vulnerable to security.

(Example of block chain generation system 200)
Next, an example of a block chain generation system 200 to which the block chain generation apparatus 100 shown in FIG. 1 is applied will be described using FIG.

  FIG. 2 is an explanatory view showing an example of the block chain generation system 200. As shown in FIG. In FIG. 2, the block chain generation system 200 includes one or more nodes 201 in a first organization and one or more nodes 202 in a second organization.

  In the first organization, one or more nodes 201 are connected via a wired or wireless network 211. The network 211 is, for example, a local area network (LAN) or a wide area network (WAN).

  In the second organization, one or more nodes 202 are connected via a wired or wireless network 212. The network 212 is, for example, a LAN or a WAN.

  In the block chain generation system 200, the one or more nodes 201 in the first organization and the one or more nodes 202 in the second organization are wired in response to the merger of the first organization and the second organization. Or connected via a wireless network 210. The network 210 is, for example, the Internet.

  The node 201 is a computer that manages block chains in the first organization. The node 201 is realized by the block chain generation device 100 shown in FIG. The node 201 is, for example, a server, a PC (Personal Computer), a tablet terminal, a smartphone, a wearable terminal, or the like.

  The node 202 is a computer that manages block chains in the second organization. The nodes 202 are realized by the block chain generation device 100 shown in FIG. The node 202 is, for example, a server, a PC, a tablet terminal, a smartphone, a wearable terminal, or the like.

(Hardware configuration example of block chain generation device 100)
Next, a hardware configuration example of the block chain generation device 100 will be described with reference to FIG.

  FIG. 3 is a block diagram showing an example of the hardware configuration of the block chain generation device 100. As shown in FIG. In FIG. 3, the block chain generation device 100 includes a central processing unit (CPU) 301, a memory 302, a network I / F (Interface) 303, a recording medium I / F 304, and a recording medium 305. Also, each component is connected by a bus 300.

  Here, the CPU 301 is in charge of overall control of the block chain generation device 100. The memory 302 includes, for example, a read only memory (ROM), a random access memory (RAM), and a flash ROM. Specifically, for example, a flash ROM or a ROM stores various programs, and a RAM is used as a work area of the CPU 301. The program stored in the memory 302 is loaded into the CPU 301 to cause the CPU 301 to execute coded processing. The memory 302 stores, for example, a block chain.

  The network I / F 303 is connected to the networks 210, 211, 212 and the like through communication lines, and is connected to another computer through the networks 210, 211, 212 and the like. A network I / F 303 interfaces the networks 210, 211, 212, etc. with the inside, and controls input / output of data from other computers. For example, a modem or a LAN adapter may be employed as the network I / F 303.

  The recording medium I / F 304 controls read / write of data with respect to the recording medium 305 according to the control of the CPU 301. The recording medium I / F 304 is, for example, a disk drive, a solid state drive (SSD), or a universal serial bus (USB) port. The recording medium 305 is a non-volatile memory that stores data written under the control of the recording medium I / F 304. The recording medium 305 is, for example, a disk, a semiconductor memory, a USB memory, or the like. The recording medium 305 may be removable from the block chain generation device 100.

  The block chain generation device 100 may have, for example, a keyboard, a mouse, a display, a printer, a scanner, a microphone, a speaker, and the like in addition to the components described above. Also, the block chain generation device 100 may have a plurality of recording medium I / F 304 and recording medium 305. Further, the block chain generation device 100 may not have the recording medium I / F 304 or the recording medium 305.

(Memory content of block 400)
Next, the storage contents of the block 400 will be described as an example of the block included in the block chain with reference to FIG. The block 400 is realized by, for example, a storage area such as the memory 302 or the recording medium 305 of the block chain generation device 100 illustrated in FIG. 3.

  FIG. 4 is an explanatory diagram of an example of the storage content of the block 400. As shown in FIG. As shown in FIG. 4, the block 400 has fields of an immediately preceding hash value, a nonce, and a transaction ID list. The block 400 is generated by setting information in each field.

  In the field of the immediately preceding hash value, a hash value corresponding to the immediately preceding block added to the block chain immediately before the block 400 is set. The hash value corresponding to the immediately preceding block is, for example, a hash value indicating the immediately preceding block, which is calculated by substituting the immediately preceding block into a predetermined function. In the nonce field, a freely settable value called nonce is set. Information on past transactions is set in the field of the transaction ID list. The information on the transaction is, for example, an ID for identifying the transaction.

(Example of functional configuration of block chain generation system 200)
Next, a functional configuration example of the block chain generation system 200 will be described. The block chain generation system 200 has a first addition unit and a second addition unit.

  The first adding unit adds an intermediate block to each of the plurality of block chains. The first addition unit is, for example, a block that implements each functional unit shown in FIG. 5 of the block chain generation device 100 that implements one or more nodes 201 in a first organization, and a block that implements one or more nodes 202 in a second organization. It is realized by each functional unit shown in FIG. 5 of the chain generation device 100.

  The second adding unit adds a block having a third hash value common to each of the plurality of block chains to each of the plurality of block chains. The second addition unit is, for example, a block that implements each functional unit shown in FIG. 5 of the block chain generation device 100 that implements one or more nodes 201 in the first organization, and a block that implements one or more nodes 202 in the second organization. It is realized by each functional unit shown in FIG. 5 of the chain generation device 100.

(Example of functional configuration of block chain generation device 100)
Next, a functional configuration example of the block chain generation device 100 will be described using FIG.

  FIG. 5 is a block diagram showing an example of a functional configuration of the block chain generation device 100. As shown in FIG. The block chain generation device 100 includes a storage unit 500, an acquisition unit 501, an addition unit 502, and an output unit 503.

  The storage unit 500 is realized by, for example, a storage area such as the memory 302 or the recording medium 305 illustrated in FIG. 3. Although the case where the storage unit 500 is included in the block chain generation device 100 will be described below, the present invention is not limited to this. For example, the storage unit 500 may be included in an apparatus different from the block chain generation apparatus 100, and the storage content of the storage unit 500 may be referable from the block chain generation apparatus 100.

  The acquisition unit 501 to the output unit 503 are functions as a control unit. Specifically, for example, the acquisition unit 501 to the output unit 503 cause the CPU 301 to execute a program stored in a storage area such as the memory 302 or the recording medium 305 illustrated in FIG. 3, or the network I / F 303. To realize that function. The processing result of each functional unit is stored, for example, in a storage area such as the memory 302 or the recording medium 305 shown in FIG.

  The storage unit 500 stores block chains. A block chain is a linked list of one or more blocks. A block is a data set that summarizes data. An example of the block is block 400 shown in FIG. A block has a plurality of items. The block has, for example, a first item and a second item. The first item of the block is, for example, an item of an immediately preceding hash value in which a hash value indicating the block connected immediately before the block is set. Also, the first item may be an item of nonce or an item of transaction ID list. The second item included in the block is, for example, an item of nonce. The second item may be the item of the immediately preceding hash value or the item of the transaction ID list. Thereby, the storage unit 500 can make the block chain referable.

  The storage unit 500 also stores various information used for processing of each functional unit. The storage unit 500 stores, for example, a predetermined function. The predetermined function is a hash function that calculates a hash value indicating a block based on the block. The predetermined function is, for example, a function that calculates a third hash value based on the values of a plurality of items included in the block. Specifically, the predetermined function is a function in which the third hash value to be calculated becomes identical even if the value of the first item and the value of the second item among the plurality of items included in the block are interchanged. It is. As a result, the storage unit 500 can make reference to various types of information used in the processing of each functional unit to each functional unit.

  The acquisition unit 501 acquires a hash value corresponding to the latest block of the block chain managed by the own device. The hash value corresponding to the latest block is, for example, a hash value obtained by copying the hash value set to the latest block. The hash value corresponding to the latest block is, for example, a hash value indicating the latest block calculated by substituting the latest block into a predetermined function. For example, when the acquisition unit 501 does not calculate the hash value corresponding to the latest block of the block chain managed by the own device, the acquisition unit 501 may use the hash value corresponding to the latest block of the block chain managed by the own device. Receive from another device. As a result, the acquisition unit 501 can acquire information used to generate an intermediate block and provide the information to the addition unit 502.

  The acquisition unit 501 acquires a hash value corresponding to the latest block of a block chain managed by another device. The hash value corresponding to the latest block is, for example, a hash value obtained by copying the hash value set to the latest block. The hash value corresponding to the latest block is, for example, a hash value indicating the latest block calculated by substituting the latest block into a predetermined function. The acquisition unit 501 receives a hash value corresponding to the latest block of a block chain managed by another device from the other device. As a result, the acquisition unit 501 can acquire information used to generate an intermediate block and provide the information to the addition unit 502.

  The adding unit 502 adds an intermediate block to the block chain managed by the own device. Here, the intermediate blocks added to the respective block chains of the plurality of block chains may not be identical, but when assigned to a predetermined function, the third hash calculated from the predetermined function The values can be identical.

  The intermediate block added to the block chain managed by the own device is, for example, the first hash value corresponding to the latest block of the block chain managed by the own device and the latest block of the block chain managed by another device And a corresponding second hash value. For example, the first hash value is set to the value of the first item, and the second hash value is set to the value of the second item for the intermediate block added to the block chain managed by the own device.

  Specifically, in the intermediate block, the first hash value is set to the value of the immediately preceding hash value item, and the second hash value is set to the nonce item value. Moreover, specifically, the first hash value may be set to the value of the item of the immediately preceding hash value, and the second hash value may be set to the value of the item of the transaction ID list. Moreover, specifically, the first hash value may be set to the value of the item of the nonce, and the second hash value may be set to the value of the item of the transaction ID list.

  More specifically, the adding unit 502 sets the first hash value set in the latest block of the block chain managed by the own device and the second hash value set in the latest block of the block chain managed by another device. Add an intermediate block with a hash value. The adding unit 502 adds an intermediate block to a block chain managed by the own apparatus as in the operation example 1 described later with reference to FIGS. 7 to 18 or the operation example 2 described later with reference to FIG. As a result, the adding unit 502 can reduce the amount of processing by using the calculated hash value.

  Specifically, the adding unit 502 has a first hash value indicating the latest block of the block chain managed by the own device and a second hash value indicating the latest block of the block chain managed by the other device. An intermediate block may be added. The adding unit 502 adds an intermediate block to a block chain managed by the own device, as in the operation example 3 described later with reference to FIGS. 21 and 22. As a result, the adding unit 502 can determine whether or not the block added immediately before the intermediate block in the block chain managed by the own apparatus has been tampered with based on the first hash value. In addition, the adding unit 502 can determine whether the block added immediately before the intermediate block in the block chain managed by the other device has been tampered with based on the second hash value.

  After adding the intermediate block, the adding unit 502 adds a common block to the block chain managed by the own device. The common block is a block commonly added to each block chain. The common block has a third hash value. The common block sets the third hash value to the value of the first item. The third hash value is a hash value indicating an intermediate block.

  The adding unit 502 uses, for example, a predetermined function based on the first hash value and the second hash value of the intermediate block added to the block chain managed by the own device, and uses the third hash value. calculate. Then, the adding unit 502 adds a common block having the third hash value to the block chain managed by the own device. Thus, the adding unit 502 can subsequently add the same block to each block chain, and can share a plurality of block chains.

  The adding unit 502 may calculate, for example, in addition to the third hash value, a fourth hash value indicating a block added immediately before the intermediate block in each block chain. Then, the adding unit 502 adds a common block further having a fourth hash value in addition to the third hash value to the block chain managed by the own apparatus. Thus, the adding unit 502 can determine whether the block added immediately before the intermediate block in each block chain is tampered with based on the fourth hash value.

  The output unit 503 outputs the processing result of each functional unit. The output format is, for example, display on a display, print output to a printer, transmission to an external device by the network I / F 303, or storage in a storage area such as the memory 302 or the recording medium 305. Thus, the output unit 503 can notify the user of the processing result of each functional unit, and support management and operation of the block chain generation device 100, for example, updating of setting values of the block chain generation device 100, and the like. it can. Then, the output unit 503 can improve the convenience of the block chain generation device 100.

  Here, although the case where block chain generation device 100 realizes each functional part independently was explained, it does not restrict to this. For example, as described later with reference to FIG. 6, in the block chain generation system 200, there may be a case where a plurality of block chain generation devices 100 cooperate to realize each functional unit.

(Example of functional configuration of block chain generation system 200)
Next, a functional configuration example of the block chain generation system 200 will be described using FIG.

  FIG. 6 is a block diagram showing a functional configuration example of the block chain generation system 200. As shown in FIG. The block chain generation system 200 includes, for example, a block chain generation device 100 including a hash value calculation unit 601 and a block generation unit 602.

  Also, the block chain generation system 200 includes, for example, a block chain generation device 100 including an integration preparation unit 603. Also, the block chain generation system 200 includes, for example, a block chain generation device 100 including an integration unit 604.

  The hash value calculation unit 601 calculates a hash value indicating a block added immediately before the block chain managed by the own device. The block generation unit 602 generates a block in which the hash value calculated by the hash value calculation unit 601 is set as the value of the item of the hash value, and adds the block to the block chain managed by the own device.

  The integration preparation unit 603 generates an intermediate block. The integration preparation unit 603 adds the generated intermediate block to the block chain managed by the own device stored in the memory 302 of the own device. The integration preparation unit 603 implements part of the operation of the addition unit 502. The integration unit 604 generates a common block. The integration unit 604 adds the generated common block to the block chain managed by the own device stored in the memory 302 of the own device. The integration unit 604 implements part of the operation of the addition unit 502.

(Operation example 1 of block chain generation device 100)
Next, an operation example 1 of the block chain generation device 100 will be described using FIGS. 7 to 18.

  7 to 18 are explanatory diagrams showing an operation example 1 of the block chain generation device 100. FIG. Specifically, FIG. 7 illustrates an example of a situation in which a block chain in each tissue of a plurality of tissues is to be shared among the tissues.

  As shown in FIG. 7, the company A block chain is stored in company A. A company B block chain is stored in company B. Here, in a situation where company A and company B merge or associate, there is a case where company A block chain and company B block chain may be shared and used as company AB block chain.

  Here, even when company A block chain and company B block chain are common, company A employee can refer to company A block chain and company AB block chain, but refer to company B block chain It is desirable not to be possible. On the other hand, it is desirable that a company B employee can refer to the company B block chain and the company AB block chain but can not refer to the company A block chain.

  In the following description, the company A block chain may be described as "chain A". In the following description, the company B block chain may be described as "chain B". Next, it transfers to description of FIG. 8, and the flow of addition of the block with respect to a block chain in A company and B company is demonstrated.

  FIG. 8 specifically shows the additional flow of blocks to the block chain. As shown in FIG. 8, the block chain generation device 100 adds new blocks to the block chain at regular intervals. Here, an operation of the block chain generation device 100 after the block 1 is added to the block chain will be described.

  Specifically, the block chain generation device 100 substitutes the latest block 1 of the block chain into a hash function, and calculates a hash value "hash1" indicating the latest block 1. Next, the block chain generation device 100 generates a new block 2 in which the calculated hash value “hash1” is set to the value of the item of the previous hash value. Then, the block chain generation device 100 adds the generated block 2 to the block chain.

  The hash function substitutes the value of the immediately preceding hash value item, the value of the nonce item, and the value of the transaction ID list item to calculate a hash value. The hash function calculates the same hash value even if, for example, the value of the immediately preceding hash value item and the value of the nonce item are interchanged. The hash function is represented, for example, by the following equation (1) or the following equation (2).

    Hash value = f (value of immediately preceding hash value item * value of nonce item * value of item of transaction ID list) ··· (1)

    Hash value = f (value of immediately preceding hash value item) * f (value of nonce item)-f (value of item of transaction ID list) (2)

  Here, f () is a SHA-256 hash function. * Indicates multiplication. -Indicates subtraction. In the above equations (1) and (2), any operator @ satisfying A @ B = B @ A may be used instead of *. In the above formulas (1) and (2), for example, + may be used instead of *. In the above equation (2), an arbitrary operator @ may be used instead of-.

  Similarly, the block chain generation device 100 substitutes the latest block 2 of the block chain into the hash function to calculate the hash value “hash2”, and sets the calculated hash value “hash2” as the value of the item of the previous hash value Generate a new block 3. The block chain generation device 100 adds the generated block 3 to the block chain.

  Thus, the block chain generation device 100 adds new blocks to the block chain. When adding a block, the block chain generation device 100 realizes a block chain concatenation by calculating a hash value indicating the immediately preceding block and including it in the block to be added. Next, it transfers to description of FIG. 9, and demonstrates the flow of commonization of the block chain to which a block is added.

  FIG. 9 shows the flow of commonization of block chains. As shown in FIG. 9, at the timing when company A and company B merge, chains A and B are shared, and after time when company A and company B merge, neither chain A nor chain B Make the same block be added. As a result, after the timing at which the company A and the company B merge, the same block is stored in the company A and the company B.

  Specifically, in the example of FIG. 9, blocks 931 and 932 are added to the chain A after the blocks 911 to 913. On the other hand, the same blocks 931 and 932 as those of the chain A are added to the chain B after the blocks 921 to 923. Next, it transfers to description of FIG. 10, and the specific example of commonization of a block chain is demonstrated.

  FIG. 10 shows a specific example of block chain sharing. In the example of FIG. 10, before company A and company B merge, the chain A in company A includes blocks 1011 and 1012. Here, it transfers to description of FIG. 11, and the specific example of the newest block 1012 in the chain A is demonstrated.

  FIG. 11 shows an example of the latest block 1012 in chain A. As shown in FIG. 11, in block 1012, “A 11.. 11” is set in the item of the immediately preceding hash value. The block 1012 sets "A22..22" in the item of nonce. The block 1012 sets "A33..33, A44..44, ..." in the item of the transaction ID list. The immediately preceding hash value and the nonce are, for example, 256 bits.

  Returning to the description of FIG. 10, before company A and company B merge, chain B in company B includes blocks 1021 and 1022. Here, it transfers to description of FIG. 12, and the example of the newest block 1022 in the chain B is demonstrated.

  FIG. 12 shows an example of the latest block 1022 in chain B. As shown in FIG. 12, in block 1022, "B55..55" is set in the item of the immediately preceding hash value. In block 1022, "B66..66" is set in the item of nonce. In block 1022, "B77..77, B88..88, ..." is set in the item of the transaction ID list. The immediately preceding hash value and the nonce are, for example, 256 bits.

  Returning to the explanation of FIG. 10, the block chain generating device 100 on the side of company A generates, for example, a block 1013 to be an intermediate block in response to the merger of company A and company B. In the following description, the block chain generation device 100 on the A company side may be described as “block chain generation device 100A”.

  The block chain generation device 100A sets the hash value “hashA” set in the immediately preceding block 1012 in the value of the item of the immediately preceding hash value of the block 1013. Further, the block chain generation device 100A sets the hash value “hash B” set in the block 1022 of the chain B to the value of the nonce item of the block 1013. The item of the transaction ID list of block 1013 is empty.

  Here, the case where the block chain generation device 100A sets the hash value “hashB” set in the block 1022 of the chain B to the value of the nonce item of the block 1013 has been described, but the present invention is not limited thereto. For example, the block chain generation device 100A may set the hash value “hash B” set in the block 1022 of the chain B to the value of the item of the transaction ID list of the block 1013.

  The block chain generation device 100A adds the generated block 1013 to the chain A. Here, it transfers to description of FIG. 13, and the specific example of the block 1013 is demonstrated.

  FIG. 13 shows a specific example of the block 1013. As shown in FIG. 13, in the block 1013, “A11..11” copied from the block 1012 is set in the item of the immediately preceding hash value. In block 1013, “B55..55” copied from block 1022 is set in the item of nonce. In block 1013, "0" is set in the item of the transaction ID list. The immediately preceding hash value and the nonce are, for example, 256 bits.

  Returning to the explanation of FIG. 10, the block chain generation device 100 on the side of company B generates, for example, a block 1023 to be an intermediate block in response to the merger of company A and company B. In the following description, the block chain generation device 100 on the B company side may be referred to as “block chain generation device 100B”.

  The block chain generation device 100 </ b> B sets the hash value “hashB” set in the immediately preceding block 1022 in the value of the item of the immediately preceding hash value of the block 1023. Further, the block chain generation device 100B sets the hash value “hashA” set in the block 1012 of the chain A to the value of the item of the nonce of the block 1023. The item of the transaction ID list of block 1023 is empty.

  Here, the case where the block chain generation device 100B sets the hash value “hashA” set in the block 1012 of the chain A to the value of the nonce item of the block 1023 has been described, but the present invention is not limited thereto. For example, the block chain generation device 100B may set the hash value “hashA” set in the block 1012 of the chain A to the value of the item of the transaction ID list of the block 1023.

  The block chain generation device 100B adds the generated block 1023 to the chain B. Here, it transfers to description of FIG. 14, and the example of a block 1023 is demonstrated.

  FIG. 14 shows a specific example of block 1023. As shown in FIG. 14, in block 1023, "B55..55" copied from block 1022 is set in the item of the immediately preceding hash value. In block 1023, "A11..11" copied from block 1012 is set in the item of nonce. In block 1023, “0” is set in the item of the transaction ID list. The immediately preceding hash value and the nonce are, for example, 256 bits.

  As described above, the block chain generation device 100A and the block chain generation device 100B may generate the block 1013 and the block 1023 such that the same hash value is calculated when substituted into the hash function. it can. Thus, the block chain generation device 100A and the block chain generation device 100B can be configured such that the blocks added to the chain A and the chain B are the same next. Next, it transfers to description of FIG.

  As shown in FIG. 15, for example, when the block 1013 is added to the chain A, the block chain generation device 100A generates a new block 1511 based on the block 1013.

  The block chain generation device 100A sets the hash value “hashAB” calculated by substituting the immediately preceding block 1013 into the hash function in the value of the item of the immediately preceding hash value of the block 1511. Further, the block chain generation device 100A sets “nonce AB” to the value of the item of the nonce of the block 1511. The item of the transaction ID list of block 1511 is empty.

  The hash function substitutes the value of the immediately preceding hash value item, the value of the nonce item, and the value of the transaction ID list item to calculate a hash value. The hash function calculates the same hash value even if, for example, the value of the immediately preceding hash value item and the value of the nonce item are interchanged. The hash function is represented, for example, by the above equation (1) or the above equation (2).

  The block chain generation device 100A adds the generated block 1511 to the chain A. Here, it transfers to description of FIG. 16, and the example of a block 1511 is demonstrated.

  FIG. 16 shows a specific example of the block 1511. As shown in FIG. 16, in the block 1511, the hash value “h (A11.. 11, B55.. 55, 0)” calculated from the block 1013 is set in the item of the immediately preceding hash value. h (p, n, t) indicates a hash value calculated based on the immediately preceding hash value p, the nonce n, and the transaction ID list t. A block 1511 sets "AB99..99" in the item of nonce. In block 1511, “0” is set in the item of the transaction ID list. The immediately preceding hash value and the nonce are, for example, 256 bits.

  Returning to the explanation of FIG. 15, for example, when adding the block 1023 to the chain B, the block chain generation device 100B generates a new block 1521 based on the block 1023.

  The block chain generation device 100B sets the hash value “hashAB” calculated by substituting the immediately preceding block 1023 into the hash function in the value of the item of the immediately preceding hash value of the block 1521. Further, the block chain generation device 100B sets “nonce AB” to the value of the item of the nonce of the block 1521. The item of the transaction ID list of block 1521 is empty.

  The hash function substitutes the value of the immediately preceding hash value item, the value of the nonce item, and the value of the transaction ID list item to calculate a hash value. The hash function calculates the same hash value even if, for example, the value of the immediately preceding hash value item and the value of the nonce item are interchanged. The hash function is represented, for example, by the above equation (1) or the above equation (2).

  The block chain generation device 100B adds the generated block 1521 to the chain B. Here, it transfers to description of FIG. 17, and the specific example of block 1521 is demonstrated.

  FIG. 17 shows a specific example of the block 1521. As shown in FIG. 17, in the block 1521, the hash value “h (B55..55, A11. .. 11, 0)” calculated from the block 1023 is set in the item of the immediately preceding hash value. A block 1521 sets "AB99..99" in the item of nonce. In block 1521, “0” is set in the item of the transaction ID list. The immediately preceding hash value and the nonce are, for example, 256 bits.

  Here, as described above, the hash function calculates, for example, the same hash value even when the value of the item of the immediately preceding hash value and the value of the item of the nonce are interchanged. Therefore, h (A11..11, B55..55, 0) = h (B55..55, A11..11, 0). As a result, block 1511 and block 1521 become identical. As a result, after that, the block chain generation device 100A and the block chain generation device 100B can share the chains A and B. Next, it transfers to description of FIG.

  As shown in FIG. 18, after the block 1511 is added to the chain A and the block 1521 is added to the chain B, the block chain generation device 100A and the block chain generation device 100B are connected via the network 210. Be done. Then, the block chain generation device 100A and the block chain generation device 100B share, for example, information related to a transaction via the network 210.

  As a result, in the following, the same block is added to the chain A and the chain B, and the chain A and the chain B are shared and used as the chain AB. Further, since the evidence that the chain A and the chain B are made common remains in the chain A and the chain B, it is possible later to determine the timing at which the chain A and the chain B are made common. .

  Here, the block 1511 added to the chain A and the block 1521 added to the chain B may further include a hash value indicating the block 1012 and a hash value indicating the block 1022. As a result, it is possible to determine the presence or absence of tampering with the block 1012 and the block 1022 later.

(An example of block chain management processing procedure in the operation example 1)
Next, an example of the block chain management processing procedure in the operation example 1 will be described using FIG.

  FIG. 19 is a flowchart of an example of a block chain management process procedure according to the first operation example. The block chain generation device 100 acquires the hash value set in the value of the item of the hash value of the immediately preceding block in the block chain managed by the own device (step S1901).

  Next, the block chain generation device 100 receives, from the other device, the hash value set in the value of the item of the hash value of the immediately preceding block in the block chain managed by the other device (step S1902). Then, the block chain generation device 100 sets the acquired hash value in the item of the hash value, and generates a new block in which the received hash value is set in the item of the nonce, and the block managed by the own device It is added to the chain (step S1903).

  Next, the block chain generation device 100 calculates a hash value indicating the added block (step S1904). Then, the block chain generation device 100 generates a new block in which the calculated hash value is set in the item of the hash value, and adds it to the block chain managed by the own device (step S1905).

  Next, the block chain generation device 100 starts a cooperative operation with another device (step S1906). Then, the block chain generation device 100 ends the block chain management process. Thus, the block chain generation device 100 can share a plurality of block chains.

(Operation example 2 of block chain generation device 100)
Next, operation example 2 of the block chain generation device 100 will be described using FIG. The operation example 1 is an operation example in the case where two block chains are shared in the block chain generation system. On the other hand, operation example 2 is an operation example in which three or more block chains are shared in the block chain generation system.

  FIG. 20 is an explanatory diagram of an operation example 2 of the block chain generation device 100. The example of FIG. 20 is an example of a case where the chain A in A company, the chain B in B company, and the chain C in C company are made common when A company, B company and C company merge. is there.

  Before the merger, Chain A in Company A includes blocks 2011 and 2012. Before the merger, chain B in company B includes blocks 2021 and 2022. Before the merger, chain C in company C includes blocks 2031 and 2032.

  For example, the block chain generation device 100 on the A company side generates a block 2013 according to the merger. In the following description, the block chain generation device 100 on the A company side may be described as “block chain generation device 100A”. The block chain generation device 100A sets the hash value “hashA” set in the immediately preceding block 2012 to the value of the item of the immediately preceding hash value of the block 2013.

  Further, the block chain generation device 100A multiplies the hash value “hashB” set in the block 2022 of the chain B and the hash value “hashC” set in the block 2032 of the chain C. The block chain generation device 100A sets the multiplication result “hashB * hashC” to the value of the item of the nonce of the block 2013. The item of the transaction ID list of block 2013 is empty. The block chain generation device 100A adds the generated block 2013 to the chain A.

  The B-side block chain generation apparatus 100 generates a block 2023, for example, according to the merger. In the following description, the block chain generation device 100 on the B company side may be referred to as “block chain generation device 100B”. The block chain generation device 100 </ b> B sets the hash value “hashB” set in the immediately preceding block 2022 in the value of the item of the immediately preceding hash value of the block 2023.

  Further, the block chain generation device 100B multiplies the hash value “hashA” set in the block 2012 of the chain A by the hash value “hashC” set in the block 2032 of the chain C. The block chain generation device 100B sets the multiplication result “hashA * hashC” to the value of the item of the nonce of the block 2023. The item of the transaction ID list of block 2023 is empty. The block chain generation device 100B adds the generated block 2023 to the chain B.

  For example, the block chain generation device 100 on the side of company C generates a block 2033 according to the merger. In the following description, the block chain generation device 100 on company C may be referred to as “block chain generation device 100C”. The block chain generation device 100C sets the hash value “hashC” set in the immediately preceding block 2032 in the value of the item of the immediately preceding hash value of the block 2033.

  Further, the block chain generation device 100C multiplies the hash value “hashA” set in the block 2012 of the chain A by the hash value “hashB” set in the block 2022 of the chain B. The block chain generation device 100C sets the multiplication result “hashA * hashB” to the value of the nonce item of the block 2033. The item of the transaction ID list of block 2033 is empty. The block chain generation device 100C adds the generated block 2033 to the chain C.

  As described above, the block chain generation devices 100A to 100C can generate the block 2013, the block 2023, and the block 2033 such that the same hash value is calculated when substituting the hash function. As a result, the block chain generation device 100A, the block chain generation device 100B, and the block chain generation device 100C are configured such that the blocks added to the chain A, the chain B, and the chain C next become identical. Can be

  For example, when the block 2013 is added to the chain A, the block chain generation device 100A generates a new block 2014 based on the block 2013. The block chain generation device 100A sets the hash value “hashABC” calculated by substituting the immediately preceding block 2013 into the hash function in the value of the item of the immediately preceding hash value of the block 2014.

  Further, the block chain generation device 100A sets “nonceABC” to the value of the item of the nonce of the block 2014. The item of the transaction ID list of block 2014 is empty. The hash function is represented, for example, by the above equation (1). The block chain generation device 100A adds the generated block 2014 to the chain A.

  For example, when the block 2023 is added to the chain B, the block chain generation device 100B generates a new block 2024 based on the block 2023. The block chain generation device 100B sets the hash value “hashABC” calculated by substituting the immediately preceding block 2023 into the hash function in the value of the item of the immediately preceding hash value of the block 2024.

  In addition, the block chain generation device 100B sets “nonceABC” to the value of the item of the nonce of the block 2024. The item of the transaction ID list of block 2024 is empty. The hash function is represented, for example, by the above equation (1). The block chain generation device 100B adds the generated block 2024 to the chain B.

  For example, when the block 2033 is added to the chain C, the block chain generation device 100C generates a new block 2034 based on the block 2033. The block chain generation device 100C sets the hash value “hashABC” calculated by substituting the immediately preceding block 2033 into the hash function in the value of the item of the immediately preceding hash value of the block 2034.

  Further, the block chain generation device 100C sets “nonceABC” to the value of the item of the nonce of the block 2034. The item of the transaction ID list of block 2034 is empty. The hash function is represented, for example, by the above equation (1). The block chain generation device 100C adds the generated block 2034 to the chain C.

  Here, for example, the hash function represented by the equation (1) is the same even if the hashA, hashB, and hashC are set to the value of the immediately preceding hash value item and the value of the nonce item. The hash value of can be calculated. As a result, block 2014, block 2024 and block 2034 are identical. As a result, thereafter, the block chain generation device 100A, the block chain generation device 100B, and the block chain generation device 100C can share the chain A, the chain B, and the chain C.

(An example of block chain management processing procedure in the operation example 2)
An example of the block chain management processing procedure in the operation example 2 is the same as the example of the block chain management processing procedure in the operation example 1 shown in FIG.

(Operation example 3 of block chain generation device 100)
Next, operation example 3 of the block chain generation device 100 will be described with reference to FIGS. 21 and 22. The operation example 1 is an operation example in which the block chain generation device 100 copies the hash value of the immediately preceding block to the intermediate block when the intermediate block is generated. On the other hand, operation example 3 is an operation example in the case where the block chain generation device 100 generates an intermediate block, calculates a hash value indicating the immediately preceding block, and includes it in the intermediate block.

  21 and 22 are explanatory diagrams showing an operation example 3 of the block chain generation device 100. FIG. The example of FIG. 21 is an example of a case where the chain A in company A and the chain B in company B are made common when company A and company B merge.

  Before the merger, chain A in company A includes blocks 2111, 2112. Before the merger, the chain B in company B includes blocks 2121 and 2122.

  For example, the block chain generation device 100 on the A company side generates a block 2113 according to the merger. In the following description, the block chain generation device 100 on the A company side may be described as “block chain generation device 100A”.

  The block chain generation device 100 </ b> A calculates a hash value “hashA ′” indicating the immediately preceding block 2112 using a hash function. The hash function is represented, for example, by the above equation (1) or the above equation (2). The block chain generation device 100 </ b> A sets the calculated hash value “hashA ′” as the value of the item of the immediately preceding hash value of the block 2113.

  The block chain generation device 100A receives, from the block chain generation device 100B, the hash value “hash B ′” indicating the block 2122 of the chain B calculated by the block chain generation device 100B using the hash function. The block chain generation device 100 </ b> A sets the received hash value “hash B ′” to the value of the item of nonce of block 2113. The item of the transaction ID list of block 2113 is empty. The block chain generation device 100A adds the generated block 2113 to the chain A.

  The B-side block chain generation device 100 generates a block 2123, for example, according to the merger. In the following description, the block chain generation device 100 on the B company side may be referred to as “block chain generation device 100B”.

  The block chain generation device 100 </ b> B calculates a hash value “hashB ′” indicating the immediately preceding block 2122 using a hash function. The hash function is represented, for example, by the above equation (1) or the above equation (2). The block chain generation device 100 </ b> B sets the calculated hash value “hash B ′” as the value of the item of the immediately preceding hash value of the block 2123.

  The block chain generation device 100B receives, from the block chain generation device 100A, the hash value “hashA ′” indicating the block 2112 of the chain A calculated by the block chain generation device 100A using the hash function. The block chain generation device 100 </ b> B sets the received hash value “hashA ′” to the value of the item of the nonce of block 2123. The item of the transaction ID list of block 2123 is empty. The block chain generation device 100B adds the generated block 2123 to the chain B.

  As described above, the block chain generation device 100A and the block chain generation device 100B can generate the block 2113 and the block 2123 such that the same hash value is calculated when substituted in the hash function. it can. Thus, the block chain generation device 100A and the block chain generation device 100B can be configured such that the blocks added to the chain A and the chain B are the same next.

  For example, when the block 2113 is added to the chain A, the block chain generation device 100A generates a new block 2211 based on the block 2113. The block chain generation device 100A sets the hash value “hashAB” calculated by substituting the immediately preceding block 2113 into the hash function in the value of the item of the immediately preceding hash value of the block 2211.

  Further, the block chain generation device 100A sets “nonce AB” to the value of the item of the nonce of the block 2211. The item of the transaction ID list of block 2211 is empty. The hash function is represented, for example, by the above equation (1) or the above equation (2). The block chain generation device 100A adds the generated block 2211 to the chain A.

  For example, when the block 2123 is added to the chain B, the block chain generation device 100B generates a new block 2221 based on the block 2123. The block chain generation device 100B sets the hash value “hashAB” calculated by substituting the immediately preceding block 2123 into the hash function in the value of the item of the immediately preceding hash value of the block 2221.

  Also, the block chain generation device 100B sets “nonce AB” to the value of the item of the nonce of the block 2221. The item of the transaction ID list of block 2221 is empty. The hash function is represented, for example, by the above equation (1) or the above equation (2). The block chain generation device 100B adds the generated block 2221 to the chain B.

  Here, the hash function can calculate the same hash value even if, for example, the value of the item of the immediately preceding hash value and the value of the item of the nonce are interchanged. As a result, block 2211 and block 2221 are identical. As a result, after that, the block chain generation device 100A and the block chain generation device 100B can share the chains A and B.

(An example of block chain management processing procedure in the operation example 3)
Next, an example of the block chain management processing procedure in the operation example 3 will be described using FIG.

  FIG. 23 is a flowchart of an example of a block chain management process procedure according to the third operation example. The block chain generation device 100 calculates a hash value indicating the immediately preceding block in the block chain managed by the own device (step S2301).

  Next, the block chain generation device 100 receives, from the other device, a hash value indicating the immediately preceding block in the block chain managed by the other device (step S2302). Then, the block chain generation device 100 sets the calculated hash value in the item of the hash value, and generates a new block in which the received hash value is set in the item of the nonce, and the block managed by the own device It is added to the chain (step S2303).

  Next, the block chain generation device 100 calculates a hash value indicating the added block (step S2304). Then, the block chain generation device 100 generates a new block in which the calculated hash value is set in the item of the hash value, and adds the new block to the block chain managed by the own device (step S2305).

  Next, the block chain generation device 100 starts a cooperative operation with another device (step S2306). Then, the block chain generation device 100 ends the block chain management process. Thus, the block chain generation device 100 can share a plurality of block chains.

  As described above, according to the block chain generation device 100, the first hash value corresponding to the latest block of the block chain managed by the own device and the latest block of the block chain managed by another device A second hash value can be obtained. According to the block chain generation device 100, an intermediate block having the first hash value and the second hash value can be added to the block chain managed by the own device. According to the block chain generation device 100, a block having a hash value common to a plurality of block chains can be added to a block chain managed by the own device using a predetermined function. Thereby, the block chain generation device 100 can add a block having a third hash value common to a plurality of block chains to the block chain managed by the own device, and the respective block chains are common among organizations. Can be

  According to the block chain generation device 100, even if the value of the first item and the value of the second item among the plurality of items possessed by the block are replaced as a predetermined function, the calculated hash value becomes identical. Functions can be used. According to the block chain generation device 100, it is possible to generate an intermediate block in which the first hash value is set to the value of the first item and the second hash value is set to the value of the second item. it can. Thus, the block chain generation device 100 can make the third hash values calculated from the intermediate blocks added to the respective block chains be the same.

  According to the block chain generation device 100, the first hash value is set to the value of the first item for which the hash value indicating the block connected immediately before the block is set, and the second hash value is nonce Can be set to the value of the second item to be set. Thus, the block chain generation device 100 can make the third hash values calculated from the intermediate blocks added to the respective block chains be the same.

  According to the block chain generation device 100, it is possible to use, as the first hash value, a hash value obtained by copying the hash value set in the block added immediately before the intermediate block to the block chain managed by the own device. According to the block chain generation device 100, it is possible to use, as the second hash value, a hash value obtained by copying the hash value set in the block added immediately before the intermediate block to the block chain managed by the other device. As a result, the block chain generation device 100 can copy the calculated hash value to reduce the processing amount.

  According to the block chain generation device 100, in addition to the third hash value, each block chain managed by the own device further has a fourth hash value indicating a block added immediately before the intermediate block in each block chain. Blocks can be added. Thereby, the block chain generation device 100 can determine whether or not the block added immediately before the intermediate block in each block chain is tampered with based on the fourth hash value. Therefore, the block chain generation device 100 can improve security in the block chain generation system 200.

  According to the block chain generation device 100, it is possible to use, as the first hash value, a hash value indicating a block added immediately before the intermediate block in the block chain managed by the own device. According to the block chain generation device 100, it is possible to use, as the second hash value, a hash value indicating a block added immediately before an intermediate block in a block chain managed by another device. Thus, the block chain generation device 100 can determine whether or not the block added immediately before the intermediate block is tampered with in the block chain managed by the own device based on the first hash value. Further, the block chain generation device 100 can determine whether or not the block added immediately before the intermediate block in the block chain managed by another device is tampered with based on the second hash value. Therefore, the block chain generation device 100 can improve security in the block chain generation system 200.

  According to the block chain generation device 100, a hash value indicating an intermediate block can be used as the third hash value. Thus, the block chain generation device 100 can determine whether the intermediate block has been tampered with based on the third hash value. Therefore, the block chain generation device 100 can improve security in the block chain generation system 200.

  The block chain generation method described in the present embodiment can be realized by executing a prepared program on a computer such as a personal computer or a workstation. The block chain generation program described in the present embodiment is recorded on a computer-readable recording medium such as a hard disk, flexible disk, CD-ROM, MO, or DVD, and is executed by being read from the recording medium by the computer. . In addition, the block chain generation program described in the present embodiment may be distributed via a network such as the Internet.

  The following appendices will be further disclosed regarding the embodiment described above.

(Supplementary Note 1) A first hash value corresponding to the latest block of the first block chain, for each of the first block chain and the second block chain connecting one or more blocks; A first adding unit for adding an intermediate block having a second hash value corresponding to the latest block of the second block chain;
Common to the first and second block chains based on the first hash value and the second hash value of the intermediate block respectively added to the first and second block chains A second adding unit that adds a block having the third hash value to the first and second block chains using a function capable of calculating a third hash value;
A block chain generation system characterized by having.

(Supplementary Note 2) The block has a plurality of items,
The function is a function for calculating the third hash value based on the values of the plurality of items, and the value of the first item and the value of the second item among the plurality of items are interchanged. Even if the third hash value to be calculated is the same function,
The first addition unit is
For each of the first block chain and the second block chain, a first hash value corresponding to the latest block of the block chain is set to the value of the first item, and other than the block chain The block chain generation system according to claim 1, further comprising: adding the intermediate block in which a second hash value corresponding to the latest block of another block chain in the block is set to the value of the second item. .

(Supplementary Note 3) The first item included in the block is an item to which a hash value indicating a block connected immediately before the block is set.
The block chain generation system according to appendix 2, wherein the second item included in the block is an item for which a nonce is set.

(Supplementary Note 4) The first addition unit
For each of the first block chain and the second block chain, the first hash value set to the latest block of the block chain and the latest block of other block chains other than the block chain The block chain generation system according to any one of Appendices 1 to 3, further comprising: adding the intermediate block having the second hash value.

(Supplementary Note 5) The second addition unit
For each of the first block chain and the second block chain, in addition to the third hash value, an intermediate block is added to each of the first block chain and the second block chain just before the intermediate block. The block chain generation system according to appendix 4, wherein a block further having a fourth hash value indicating the block is added.

(Supplementary Note 6) The first addition unit
For each of the first block chain and the second block chain, a first hash value indicating the latest block of the block chain and a second hash value indicating the latest block of another block chain other than the block chain The block chain generation system according to claim 1, wherein the intermediate block having a hash value of

(Supplementary Note 7) The block chain generation system according to any one of Supplementary notes 1 to 6, wherein the third hash value is a hash value indicating the intermediate block.

(Supplementary Note 8) A first hash value corresponding to the latest block of the first block chain, for each of the first block chain and the second block chain connecting one or more blocks; Add an intermediate block having a second hash value corresponding to the latest block of the second block chain,
Common to the first and second block chains based on the first hash value and the second hash value of the intermediate block respectively added to the first and second block chains Adding a block having the third hash value to the first and second block chains using a function capable of calculating a third hash value;
A block chain generation method characterized by

(Supplementary Note 9)
A first hash value corresponding to the latest block of the first block chain, for the first block chain of the first block chain connecting one or more blocks and the second block chain; Adding an intermediate block having a second hash value corresponding to the latest block of the second block chain;
A third hash value common to the first and second block chains can be calculated based on a first hash value and a second hash value of an intermediate block added to the first block chain Adding a block having the third hash value to the first block chain using a random function
A block chain generation program characterized by executing processing.

DESCRIPTION OF SYMBOLS 100 Block chain generation apparatus 110, 120 Block chain 111, 112, 114, 121, 122, 124, 400, 911-913, 921-923, 931, 1011-1013, 1021-1023, 1511, 1521, 201-1 2014, 2021-2024, 2031-2034, 2111-2113, 2121-2123, 2211-2221 block 113, 123 intermediate block 200 block chain generation system 201, 202 node 210-212 network 300 bus 301 CPU
302 Memory 303 Network I / F
304 Recording medium I / F
305 recording medium 500 storage unit 501 acquisition unit 502 addition unit 503 output unit 601 hash value calculation unit 602 block generation unit 603 integration preparation unit 604 integration unit

Claims (8)

A first hash value corresponding to the latest block of the first block chain and a second block chain for each of the first block chain and the second block chain connecting one or more blocks; Adding an intermediate block having a second hash value corresponding to the latest block of
Common to the first and second block chains based on the first hash value and the second hash value of the intermediate block respectively added to the first and second block chains A second adding unit that adds a block having the third hash value to the first and second block chains using a function capable of calculating a third hash value;
A block chain generation system characterized by having. The block has a plurality of items,
The function is a function for calculating the third hash value based on the values of the plurality of items, and the value of the first item and the value of the second item among the plurality of items are interchanged. Even if the third hash value to be calculated is the same function,
The first addition unit is
For each of the first block chain and the second block chain, a first hash value corresponding to the latest block of the block chain is set to the value of the first item, and other than the block chain The block chain generation according to claim 1, characterized in that the intermediate block is added with a second hash value corresponding to the latest block of another block chain of the block set to the value of the second item. system. The first item included in the block is an item to which a hash value indicating a block connected immediately before the block is set.
The block chain generation system according to claim 2, wherein the second item included in the block is an item for which a nonce is set. The first addition unit is
For each of the first block chain and the second block chain, the first hash value set to the latest block of the block chain and the latest block of other block chains other than the block chain The block chain generation system according to any one of claims 1 to 3, wherein the intermediate block having the second hash value and the second hash value is added. The second addition unit is
For each of the first block chain and the second block chain, in addition to the third hash value, an intermediate block is added to each of the first block chain and the second block chain just before the intermediate block. The block chain generation system according to claim 4, wherein a block further having a fourth hash value indicating the block is added. The first addition unit is
For each of the first block chain and the second block chain, a first hash value indicating the latest block of the block chain and a second hash value indicating the latest block of another block chain other than the block chain The block chain generation system according to claim 1, wherein the intermediate block having a hash value of and is added. A first hash value corresponding to the latest block of the first block chain and a second block chain for each of the first block chain and the second block chain connecting one or more blocks; Add an intermediate block with a second hash value corresponding to the latest block of
Common to the first and second block chains based on the first hash value and the second hash value of the intermediate block respectively added to the first and second block chains Adding a block having the third hash value to the first and second block chains using a function capable of calculating a third hash value;
A block chain generation method characterized by On the computer
A first hash value corresponding to the latest block of the first block chain, for the first block chain of the first block chain connecting one or more blocks and the second block chain; Adding an intermediate block having a second hash value corresponding to the latest block of the second block chain;
A third hash value common to the first and second block chains can be calculated based on a first hash value and a second hash value of an intermediate block added to the first block chain Adding a block having the third hash value to the first block chain using a random function
A block chain generation program characterized by executing processing.

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