WO2023008092A1

WO2023008092A1 - Information processing device and method for controlling same

Info

Publication number: WO2023008092A1
Application number: PCT/JP2022/026361
Authority: WO
Inventors: 幹彦亀川
Original assignee: キヤノン株式会社
Priority date: 2021-07-28
Filing date: 2022-06-30
Publication date: 2023-02-02
Also published as: JP2023018905A

Abstract

The present invention: stores a plurality of blockchain distributed ledgers, including both a registration blockchain distributed ledger that carries out a new transaction registration process and a registered transaction acquisition process, and a reference blockchain distributed ledger that carries out the registered transaction acquisition process but does not carry out the new transaction registration process; and, upon receiving a command to delete a reference blockchain distributed ledger, deletes the reference blockchain distributed ledger.

Description

Information processing device and its control method

The present invention relates to document storage using blockchain technology.

Countries and companies have documents that are important to them, such as official documents and management documents, but falsification of these important documents has become a problem. A mechanism is needed. Therefore, it is known to determine whether or not an electronic document file has been tampered with using a hash value of the electronic document file. In addition, the holding period of these documents held by the government or companies is determined, and the documents are discarded after the holding period has expired.

On the other hand, blockchain technology is known to be highly resistant to tampering.

See JP-A-2020-178240.

Japanese Patent Application Laid-Open No. 2020-178240

Blockchain technology manages stored data in a chained state, so once stored data cannot be deleted. Therefore, if blockchain technology is simply applied to stored documents, stored documents cannot be discarded in the future. Management costs will also increase.

The purpose of the present invention is to provide a technology that suppresses the bloating of the blockchain data area by making it possible to discard documents saved using blockchain technology.

The information processing apparatus in the present invention includes a registered blockchain distributed ledger that performs new transaction registration processing and registered transaction acquisition processing, and a reference blockchain distributed ledger that does not perform new transaction registration processing but performs registered transaction acquisition processing. a storage means for storing a plurality of blockchain distributed ledgers;
The information processing apparatus is characterized by comprising deletion means for deleting the reference blockchain distributed ledger in response to an instruction to delete the reference blockchain distributed ledger.

By making it possible to destroy documents stored using blockchain technology, we can provide technology that suppresses the bloating of the blockchain data area.

System configuration diagram according to the embodiment Hardware configuration diagram of a blockchain device and a client PC according to an embodiment Functional configuration diagram of a blockchain device according to an embodiment Structure diagram of transaction according to the embodiment Structural diagram of the distributed ledger according to the embodiment Structural diagram of the distributed ledger group according to the embodiment Functional configuration diagram of a client PC according to the embodiment Distributed ledger group management screen configuration diagram according to the first and second embodiments Flowchart for generating a distributed ledger group according to the first and second embodiments Flowchart for switching distributed ledgers according to the embodiment Flowchart for deleting a distributed ledger according to an embodiment Transaction operation screen configuration diagram according to the first and second embodiments Flowchart for registering a transaction according to the first embodiment Flowchart for Acquiring Transactions According to Embodiment 1 Flowchart for registering a transaction according to the second embodiment Flowchart for Acquiring Transactions According to Embodiment 2 Functional configuration diagram of a blockchain device according to Embodiment 3 Structural diagram of distributed ledger group management according to the third embodiment Distributed ledger group management screen configuration diagram according to the third embodiment Flowchart for adding a distributed ledger group according to the third embodiment Transaction operation screen configuration diagram according to the third embodiment Flowchart for registering a transaction according to the third embodiment Flowchart for Acquiring Transactions According to Embodiment 3 Flowchart for updating a transaction according to the third embodiment Distributed ledger group according to the embodiment

A mode for carrying out the present invention will be described below with reference to the drawings.

<Embodiment 1>
FIG. 1 is an overview of a blockchain device 111 and related systems. In this embodiment, the PC 101 is connected to the LAN 100 and exists within the intranet, and communicates with the blockchain device 111 via the Internet 110 . The PC 101 is used to use the functions of the blockchain device 111 using a web browser. In the present embodiment, one PC 101 is used to explain the functions, but it is not intended to limit the connection of a plurality of PCs 101 to the blockchain device 111 via the LAN 100 . Although the block chain device 111 and the PC 101 are described here, both are information processing devices.

The blockchain device 111 is a device that receives information generated by the PC 101 as a transaction and collectively manages it in blocks, thereby managing information using a highly tamper-resistant blockchain method. It is assumed that this block chain device 111 can also be configured by a plurality of units. In this embodiment, the LAN 100 of the intranet and the Internet 110 are configured separately, but the configuration in which all the devices are directly connected to the Internet or the configuration in which they are connected to the LAN 100 is not limited.

FIG. 2 is a block diagram showing the computer hardware configuration of the PC 101 and the blockchain device 111.

A Central Processing Unit (hereafter referred to as CPU) 202 controls the entire apparatus. A CPU 202 executes application programs, an OS, and the like stored in a hard disk (hereinafter referred to as HDD) 205 . It also controls the temporary storage of information, files, etc. necessary for program execution in the Random Access Memory (RAM) 203 . A Read Only Memory (hereinafter referred to as ROM) 204 is storage means (storage unit), and stores various data such as basic I/O programs therein. A RAM 203 is temporary storage means, and functions as a main memory, a work area, and the like for the CPU 202 . The HDD 205 is one of external storage means, functions as a large-capacity memory, and stores application programs such as office applications and web browsers, an OS, related programs, and the like. A display 206 is display means, and displays commands and the like input from a keyboard/mouse 207 as instruction input means. An interface 208 is an external device I/F, and connects printers, USB devices, and peripheral devices. A system bus 201 governs the flow of data within the device. A network interface card (hereinafter referred to as NIC) 209 exchanges data with external devices via the LAN 100 . Note that the configuration of the computer described above is an example, and is not limited to the configuration example shown in FIG. For example, the storage locations of data and programs can be changed to the ROM 204, RAM 203, HDD 205, etc., according to their characteristics. Unless otherwise specified in this embodiment, various processes are implemented by loading programs stored in the ROM 204 or the like into the RAM 203 or the like and executing the programs by the CPU 202 .

FIG. 3 is a block diagram showing the software configuration related to the present invention in the blockchain device 111. Unless otherwise specified, each processing unit is a control program stored in the ROM 204 of the blockchain device 111 .

The distributed ledger data storage unit 301 is a storage area for storing data related to the distributed ledger shown later in FIGS. 4A, 4B, and 4C. This is stored in the HDD 205 in the form of a database, file, or the like. The distributed ledger processing control unit 302 is for controlling distributed ledger processing using the data in the distributed ledger data storage unit 301 described above, and implements the functions of the blockchain.

The distributed ledger management data storage unit 303 is a storage area that holds information for managing the distributed ledger realized in this embodiment. As with the distributed ledger data storage unit 301, this is also stored in the HDD 205 in the form of a database, file, or the like.

The distributed ledger management processing control unit 304 is for controlling the management processing of the distributed ledger using the data in the distributed ledger management data storage unit 303 described above. A communication control unit 305 receives a processing request via the Internet 110 transmitted from a web browser of the PC 101 which is an external device. Then, it activates a predetermined process of the distributed ledger management processing control unit 304 and returns the processing result to the request source PC 101, and serves as a contact point with other network devices.

4A, 4B, and 4C are block diagrams showing the data structures of transactions 401, blocks 411, distributed ledgers 421, and distributed ledger groups 431, which are data units held by the blockchain device 111. FIG. The blockchain device 111 is a device that manages data using a method called blockchain. In this blockchain system, information is handled in units of transactions 401 shown in FIG. 4A. A transaction consists of a key 402 that uniquely represents the transaction and data 403 linked to the stored key 402 . Since the data format that can be held in the transaction 401 can be defined by the user, the format of the key 402 and the configuration of the data 403 are not particularly limited. As a structure for managing this transaction 401, a block 411 and a distributed ledger 421 shown in FIG. 4B are formed.

A block 411 consists of a plurality of transactions 401 (five in this embodiment), a distributed ledger ID 412 that is block management data, a block hash value 413, and a previous block hash value 414. In this figure,

blocks

415 and 416 having the same configuration as block 411 are used to explain the relationship between the blocks. The distributed ledger ID 412 is a value that first determines the distributed ledger 421 to which the block 411 belongs. The block hash value 413 is a hash value created using all transactions when the transactions included in the block are confirmed. In this figure, hash values calculated from five transactions, transaction 401(a) and transaction 401(b), are stored. By holding this value, the content of the transaction 401 in the block 411 can be detected to be tampered with. The previous block hash value 414 holds the block hash value 413 of the block 411 determined before its own block.

In this embodiment, the block 411 is the first block registered in the distributed ledger, so the previous block hash value 414 is set to NULL (no value). Block 415 has the block hash value 413 of block 411 as the previous block hash value in block 415 . Block 416 also has block hash value 413 of block 415 as the previous block hash value in block 416 . As a result, blocks 411, 415, and 416 are connected in the order of block 411, block 415, and block 416, and processing is required to maintain consistency for all blocks against tampering of some blocks. It becomes a configuration with the strength of nature.

In this embodiment, as shown in FIG. 4C, a distributed ledger group 431 is provided as a unit for managing a plurality of distributed ledgers 421 . The distributed ledger group 431 manages a plurality of distributed ledgers from the distributed ledger 421(a) to the distributed ledger 421(c) in the order of creation. For this reason, information for connecting the distributed ledger 421 is held at the position of the above-described transaction 401 (a), which is the head of the leading block 411 of the distributed ledger 421 . Specifically, since the top transaction 432(a) of the top distributed ledger 421(a) of the distributed ledger group 431 is the first distributed ledger 421 of the distributed ledger group, the transaction 401 with the following value is registered: do.
・Key 402: RELATED_DATA (fixed)
・Data 403: NULL (no value)

The distributed ledger 421(b) is a distributed ledger that follows the distributed ledger 421(a), and for the first transaction 432(b), a transaction 401 holding the next value is generated and registered in the block.
・Key 402: RELATED_DATA (fixed)
Data 403: Block hash value 413 held by the last block 411 recorded in the previous distributed ledger 421(a)

Similarly, in the distributed ledger 421(c), the block hash value 413 held by the last block 411 of the distributed ledger 421(b) is registered as a transaction 432(c). As a result, a distributed ledger group 431 connecting the distributed ledgers 421 is formed. In order to manage this distributed ledger group 431, the distributed ledger management data storage unit 303 holds information in the formats of Tables 1 and 2.

Table 1 is a table that stores definition information representing the distributed ledger group itself. The distributed ledger group name is the name of the distributed ledger group that presents the distributed ledger group 431 to the user. This information is used for display on the screen or the like. The data validity period is information indicating a period during which the transaction data 401 registered in the distributed ledger group 431 is determined to be valid. Transaction data 401 that has passed this period is treated as non-existent or invalid. The distributed ledger retention period is information indicating the period during which the distributed ledger 421 belonging to the distributed ledger group 431 is held. The value that can be set for this distributed ledger retention period is the same value as the data valid period or a larger value than it. Since the valid period of the transaction 401 is determined based on the valid period of data described above, it will not be shortened. Although the unit used for the data validity period and the distributed ledger retention period in this embodiment will be described as "years", other units such as "months" or "days" are not limited. A URL is information that uniquely represents a distributed ledger group used to access the distributed ledger group.

Table 2 is a table that stores information representing the distributed ledger 421 that constitutes the distributed ledger group 431.

The distributed ledger ID is information that uniquely represents the distributed ledger 421. In this embodiment, it is issued when the distributed ledger 421 is generated, and is set to the distributed ledger ID 412 of each block 411 that constitutes it.

The ledger type is information representing the role of the constituent distributed ledger 421. In this embodiment, three types of "preparation", "registration", and "reference" are used. In this embodiment, the distributed ledger 421 is operated as follows. First, when the distributed ledger 421 is generated, information is registered with the ledger type as “preparation”. It then becomes a distributed ledger 421 (Registered Blockchain Distributed Ledger) that registers new transactions 401 by changing to a "registration" type when ready for use. The “registration” type distributed ledger changes to the “reference” type by the distributed ledger switching process described later in FIG. 8, and becomes the distributed ledger 421 (reference blockchain distributed ledger) that only provides owned transaction information. The usage start date is information representing the date when each distributed ledger is to be used. The type change date is information representing the date when the ledger type was changed. A URL is information that uniquely represents a distributed ledger used when accessing the distributed ledger. The registered blockchain distributed ledger can perform new transaction registration processing and registered transaction acquisition processing. In addition, the reference blockchain distributed ledger does not register new transactions, but performs registered transaction acquisition processing. In this embodiment, the hash value of the last block of the reference blockchain distributed ledger is registered as the first transaction of a blockchain distributed ledger different from the blockchain distributed ledger.

FIG. 5 is a block diagram showing the functional configuration of the PC 101 that accesses the blockchain device 111. Each processing unit is a control program stored in the ROM 204 of the PC 101 unless otherwise specified. The transaction data storage unit 501 is a storage area for transaction data obtained by accessing the blockchain device 111 . This is stored in the HDD 205 in the form of a database, file, or the like. The blockchain access control unit 502 performs processing for accessing the blockchain device 111 . In this embodiment, since the blockchain device 111 is accessed via a web browser, it retains the functions of web browser control, display, and data communication, and accesses the blockchain device 111 via a communication control unit 503, which will be described later. connect to. The communication control unit 503 connects to the LAN 100 and controls communication with the blockchain device 111 via the Internet 110 .

A blockchain management screen 600 in FIG. 6 is an example of a screen for managing the distributed ledger group 431 and distributed ledger 421 of the blockchain device 111, and provides UI and functions for performing various operations of the blockchain device 111. .

The blockchain management screen 600 is configured as a web browser, and descriptions of the standard features of the web browser, such as the menus and URL display, will be omitted. A display area 601 is an area for displaying the components of the management screen. Although not shown, when there are too many display contents to be displayed in the area, vertical and horizontal scroll bars are displayed so that all can be displayed. The input area 602 is an area for displaying/inputting setting information of the blockchain device 111, and in this embodiment, it consists of a distributed ledger group name 603, a data validity period 604, a distributed ledger retention period 605, and a usage start date 606. The distributed ledger group name 603 is an area for designating and displaying information on the distributed ledger group name in Table 1 described above. A data validity period 604 is an area for designating and displaying information on the data validity period of Table 1 described above. In this embodiment, the unit of the period that can be set is assumed to be a year. The distributed ledger retention period 605 is an area for designating and displaying information on the distributed ledger retention period in Table 1 described above. In this embodiment, the unit of the period that can be set is assumed to be a year. The usage start date 606 is an area for specifying and displaying the usage start date of the distributed ledger group to be created. When this screen is displayed, the blockchain access control unit 502 requests the communication control unit 305 of the blockchain device 111 to acquire the distributed ledger group information via the communication control unit 503 . Upon receiving the request, the communication control unit 305 instructs the distributed ledger management processing control unit 304 to acquire the distributed ledger group information. The distributed ledger management processing control unit 304 acquires the data of Table 1 held in the distributed ledger management data storage unit 303 and provides the data via the communication control unit 305 . This screen that has received the information displays the content in each element of the input area 602 .

A group creation button 607 is a button for performing processing for creating a new distributed ledger group, and when pressed, the flowchart in FIG. 7 described later is executed. This button can be pressed only when data cannot be received at the time of the display described above.

The distributed ledger switching button 608 is a button for performing processing for switching the role of the distributed ledger, and when pressed, the flowchart in FIG. 8 described later is executed. A distributed ledger delete button 609 is a button for performing a process of deleting a distributed ledger whose retention period has passed.

FIG. 7 is a flowchart showing the process of generating the distributed ledger group 431 in the blockchain device 111.

In this embodiment, a procedure for the user to use the distributed ledger group generation process of the blockchain device 111 via the web browser of the PC 101 will be described. However, the processing of this flowchart does not limit, for example, scheduling and periodic execution by the blockchain device 111 . In this flowchart, when the group generation button 607 is pressed on the blockchain management screen 600, the communication control unit 503 of the PC 101 notifies the communication control unit 305 of the blockchain device 111 of a generation processing request. The generation processing request received by the communication control unit 305 is passed to the distributed ledger management processing control unit 304 and executed by the CPU 201 . At that time, the values of the distributed ledger group name 603, the data valid period 604, the distributed ledger retention period 605, and the usage start date 606 input to the blockchain management screen 600 are passed from the PC 101 to the blockchain device 111.

In step S701, the distributed ledger group name 603, the data validity period 604, and the distributed ledger retention period 605 received from the PC 101 are stored in the distributed ledger management data storage unit 303 in the format shown in Table 1, and the distributed ledger group 431 is generated. In step S702, the distributed ledger 421 to be registered in the generated distributed ledger group 431 is generated, and the following information is set as the distributed ledger information in Table 2.
・Distributed ledger ID: distributed ledger ID 412 set when generating distributed ledger 421
・Ledger type: “Preparation”
・Usage start date: Value of usage start date 606 ・Type change date: Setting date ・URL: Access URL to distributed ledger

It should be noted that the generation of the distributed ledger itself in the blockchain depends on the platform used, and the description of the generation procedure is omitted in this embodiment.

In step S703, the following transactions described in FIG. 4C are registered in the generated distributed ledger 421.
・Key 402: RELATED_DATA (fixed)
・Data 403: NULL (no value)

In step S704, since the distributed management ledger can be used, the following information of the distributed ledger definition is changed.
・Ledger type: “Registration”
・Type change date: Set date

After completing the processing of this flowchart, the result is notified to the PC 101 that requested the processing. The PC 101 that has received the notification displays the processing result on the screen.

FIG. 8 is a flowchart showing the process of newly generating the distributed ledger 421 in the blockchain device 111 and switching the existing registered distributed ledger to the reference distributed ledger.

In this embodiment, a case will be described in which the user uses the distributed ledger switching process of the blockchain device 111 via the web browser of the PC 101. The processing of this flowchart can also be implemented in a form in which, for example, the block chain device 111 automatically executes it periodically according to the data validity period information of the distributed ledger group definition information in Table 1. In this case, it is conceivable to schedule on a date obtained by adding the data effective period of the distributed ledger group definition information to the usage start date of the distributed ledger information whose ledger type is "registration". In this flowchart, when the distributed ledger switching button 608 is pressed on the blockchain management screen 600, the communication control unit 503 of the PC 101 notifies the communication control unit 305 of the blockchain device 111 of a distributed ledger switching processing request. The distributed ledger switching processing request received by the communication control unit 305 is passed to the distributed ledger management processing control unit 304 and executed by the CPU 201 .

In step S801 , the distributed ledger group definition information in Table 1 and the distributed ledger information in Table 2 are acquired from the distributed ledger management data storage unit 303 . In step S802, the distributed ledger 421 to be added to the distributed ledger group 431 described in the distributed ledger group definition information acquired in step S801 is generated, and the following information is set as the distributed ledger information in Table 2.
・ Distributed ledger ID: Distributed ledger ID 412 set when generating distributed ledger 421 (here, “DL-004”)
・Ledger type: “Preparation”
・Usage start date: Setting date ・Type change date: Setting date ・URL: Access URL to distributed ledger

In step S803, the distributed ledger information whose ledger type is "registration" is acquired, and the ledger type is changed to "reference". In step S804, the last block 411 of the distributed ledger 421 indicated by the distributed ledger ID of the distributed ledger information acquired in step S803 is determined, and the block hash value 413 is calculated and set. As a result, the distributed ledger 421 processed in this step becomes a distributed ledger that will not be registered thereafter.

In step S805, the management transaction 401 using the block hash value 413 calculated in step S804 is registered in the distributed ledger 421 with the distributed ledger ID DL-004 generated in step S802.
・Key 402: RELATED_DATA (fixed)
Data 403: block hash value 413 calculated in step S804

In step S806, the ledger type and type change date registered as distributed ledger information in Table 2 in step S802 are updated with the following information.
・Ledger type: “Registration”
・Use start date: Change date ・Type change date: Change date

This concludes this flow chart. By executing this flow chart, the distributed ledger to which the transaction is to be registered is switched.

FIG. 9 is a flowchart showing the process of deleting the distributed ledger 421 in the blockchain device 111. In this embodiment, a case will be described in which the user uses the distributed ledger deletion process of the blockchain device 111 via the web browser of the PC 101 . However, the processing of this flowchart can also be implemented in a form such that it is performed in conjunction with the distributed ledger switching processing of FIG. 8, or is automatically performed periodically.

The distributed ledger delete button 609 is pressed on the blockchain management screen 600. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 305 of the blockchain device 111 of the distributed ledger deletion processing request. The distributed ledger deletion processing request received by the communication control unit 305 is passed to the distributed ledger management processing control unit 304 and executed by the CPU 201 .

In step S901, the distributed ledger group definition information in Table 1 and the distributed ledger information in Table 2 are obtained from the distributed ledger management data storage unit 303. In step S902, from the distributed ledger information acquired in step S901, one item of data indicating that the ledger type that has not been selected in this step is "reference" is selected. In step S903, when the distributed ledger information can be acquired in step S902, the process proceeds to the next step S904. If there is no target information to be acquired, this flow chart ends.

In step S904, using the distributed ledger group definition information acquired in step S901 and the distributed ledger information selected in step S902, the remaining period of the retention period of the target distributed ledger 421 is calculated by the following formula.
Remaining retention period = usage start date + distributed ledger retention period - execution date of this flowchart

In step S905, it is determined whether the retention period has expired depending on whether the remaining retention period calculated in step S904 indicates a negative value. If a negative value is indicated and the retention period has expired, the process proceeds to step S906; otherwise, the process returns to step S902.

In step S906, the distributed ledger group including the distributed ledger to be deleted is corrected. Specifically, a transaction indicating that the deletion target distributed ledger has been deleted is registered in the distributed ledger group 431 to which it belongs. FIG. 23 shows a schematic diagram of the distributed ledger group 431 representing this process. This FIG. 23 explains the part related to this step at the time of deleting the distributed ledger from the configuration of the distributed ledger of the distributed ledger group 431 shown in FIG. 4C.

In FIG. 23, the target of deletion is the reference distributed ledger 421(a), and the last block hash value 2301 of this reference distributed ledger 421(a) is transferred to the registered distributed ledger 421(c) of the same distributed ledger group 431 as a transaction 2302. Indicates to add.

The information of the transaction 2301 registered in this step is as follows.
・Key 402: DELETED_DATA (fixed)
Data 403: Block hash value 413 held by the last block 411 recorded in the reference distributed ledger 421(a) to be deleted

As a result, it can be proved that the value of the leading transaction 411 indicating the connection of the distributed ledger registered in the leading distributed ledger 421 after deleting the reference distributed ledger in step S907 described later is that of the deleted distributed ledger. . As a result, it can be verified that there is no data inconsistency in the distributed ledger group 43 . In step S907, the distributed ledger 421 that matches the distributed ledger ID of the distributed ledger information selected in step S902 is deleted. In this step, the distributed ledger management processing control unit 304 requests the distributed ledger processing control unit 302 to perform the distributed ledger deletion processing by designating the distributed ledger ID. The distributed ledger processing control unit 302 deletes the target distributed ledger according to the procedure of the blockchain platform to be used. In step S908 , the distributed ledger information selected in step S902 is deleted from Table 2 of the distributed ledger management data storage unit 303 .

As described above, it is possible to safely delete stored data that is no longer needed in data management using blockchain, which is a feature of this embodiment.

Fig. 10 is an example of a transaction operation screen. A blockchain access screen 1000 is an example of a screen provided by the blockchain device 111 to the user in order to execute registration and acquisition of the transaction 401 . The blockchain access screen 1000 is configured as a web browser, and the description of the standard features of the web browser, such as menus and URL displays, will be omitted. A display area 1001 is an area for displaying the components of the access screen. Although not shown, when there are too many display contents to be displayed in the area, vertical and horizontal scroll bars are displayed so that all can be displayed.

The components of this display area 1001 can be obtained by accessing the URL held in Table 1 by the blockchain device 111.

The key information 1002 is a place to input or display information that uniquely represents information to be registered as a transaction. In this embodiment, it is assumed that a hash value calculated from a document file to be registered is input. The registration data 1003 is a place for inputting or displaying information linked to the information uniquely represented by the key information 1002 described above. In this embodiment, it is assumed that the bibliographic data held by the document file (for example, creator, place of creation, document file name, etc.) is input. Validity period 1004 displays a value that indicates the period in which information is held in this distributed ledger group 431 . In this embodiment, since the retention period is determined when creating the distributed ledger group 431, it is provided as a function that only displays the set values.

A registration button 1005 is a button for executing the registration processing of the transaction 401 described later in FIG. Acquisition button 1006 is a button for executing acquisition processing of transaction 401 described later with reference to FIG.

FIG. 11 is a flowchart showing the process of registering the transaction 401 in the distributed ledger 421 in the blockchain device 111. In this embodiment, a description will be given in which the user requests registration of the transaction 401 in the distributed ledger managed by the blockchain device 111 via the web browser of the PC 101 . However, it is also possible to execute the main registration process in cooperation with another system, and the processing form is not limited. Key information 1002 and registration data 1003 are entered on the blockchain access screen 1000, and a registration button 1005 is pressed. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 305 of the blockchain device 111 of the transaction registration processing request. At this time, both the key information 1002 and the value of the registration data 1003 input on the blockchain access screen 1000 are transmitted. The input values of the transaction registration processing request, the key information 1002 and the registration data 1003 received by the communication control unit 305 are passed to the distributed ledger management processing control unit 304 and executed by the CPU 201 .

In step S1101, the key information 1002 and the registration data 1003 input by the web browser of the PC 101 are obtained. In step S1102, from the distributed ledger information in Table 2, the distributed ledger data having the "registered" ledger type is acquired from the distributed ledger management data storage unit 303. In step S1103, it is determined whether or not the distributed ledger management data acquired in step S1102 exists. If it exists, the process proceeds to step S1104; otherwise, the process proceeds to step S1106.

In step S1104, the distributed ledger ID of the distributed ledger data obtained in step S1102 and the key information 1002 and registration data 1003 obtained in step S1101 are passed to the distributed ledger processing control unit 302 to request registration processing of the transaction 401. The distributed ledger processing control unit 302 creates and registers the following transaction 401 in the distributed ledger having the relevant divided ledger ID.
・Key 402: Key information 1002
・Data 403: Registration data 1003

It should be noted that the registration process of the transaction itself in the distributed ledger depends on the platform used, and the description of the registration procedure is omitted in this embodiment.

In step S1105, the PC 101 is notified of the transaction registration result in step S1104. In step S1106, the PC 101 is notified of an error that the distributed ledger to be registered does not exist.

After the end of this flowchart, the registration result and error are displayed on the screen of the PC 101. This is done using a standard dialog (not shown) possessed by the OS or web browser, and is explained in this embodiment. omitted.

FIG. 12 is a flowchart showing the process of acquiring registration data from a predetermined distributed ledger 421 in the blockchain device 111. In this embodiment, the user requests acquisition of the transaction 401 from the distributed ledger managed by the blockchain device 111 via the web browser of the PC 101 . However, it is also possible to execute the main registration process in cooperation with another system, and the processing form is not limited. Key information 1002 is entered on the blockchain access screen 1000, and an acquisition button 1006 is pressed. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 305 of the blockchain device 111 of the transaction acquisition processing request. At this time, the PC 101 also transmits the value of the key information 1002 input on the blockchain access screen 1000 . The transaction acquisition processing request received by the communication control unit 305 and the input value of the key information 1002 are passed to the distributed ledger management processing control unit 304 and executed by the CPU 201 .

In step S1201, the key information 1002 input by the web browser of the PC 101 is obtained. In step S1202, from the distributed ledger group definition information in Table 1 and the distributed ledger information in Table 2, all distributed ledger data whose ledger type is "registration" or "reference" are obtained from the distributed ledger management data storage unit 303, It saves in RAM203.

In step S1203, one piece of distributed ledger data with the latest type change date is selected from the distributed ledger information acquired in step S1202 and stored in the RAM 203. In step S1204, it is determined whether or not the distributed ledger data selected in step S1203 exists, and if it exists, the process proceeds to step S1205, and if it does not exist, the process proceeds to step S1208. In step S1205, the distributed ledger ID of the distributed ledger data selected in step S1203 and the key information 1002 obtained in step S1201 are passed to the distributed ledger processing control unit 302 to request acquisition processing of the transaction 401. The distributed ledger processing control unit 302 searches the transaction 401 having the value of the key information 1002 in the key 402 from the distributed ledger having the relevant divided ledger ID, and passes it to the distributed ledger management processing control unit 304 if there is a match.

The transaction search processing in the distributed ledger processing control unit 302 depends on the blockchain platform used, and the description of the search procedure is omitted in this embodiment.

In step S1206, it is determined whether or not the transaction 401 acquired in step S1205 exists, and if it exists, the process proceeds to the next step S1207, and if it does not exist, the process returns to step S1203 to search the next distributed ledger. . At this time, the distributed ledger data selected in S1203 is deleted from the RAM203.

In step S1207, the data 403 of the acquired transaction 401 is notified to the PC 101. In step S1208, the PC 101 is notified that there is no transaction data that matches the designated key information 1002. After the end of this flowchart, on the screen of the PC 101, if the data 403 can be acquired, it is displayed as the registration data 1003. FIG. When an error notification is received, similar to the flow chart of FIG. 11, the content of the error is displayed in a standard dialog (not shown) of the OS or web browser.

In steps S1203 to S1206, the distributed ledger with the latest type change date is searched first, but the distributed ledger may be searched sequentially based on a predetermined rule.

As described above, according to the first embodiment, when managing data with a retention period using a blockchain, transaction data whose retention period has expired can be deleted while safely operating a distributed ledger. . As a result, it is possible to reduce the amount of data stored in the blockchain, thereby reducing operational costs.

<Embodiment 2>
In this embodiment, an embodiment will be described in which a transaction acquisition method is different from that of the first embodiment. In this embodiment, the management part of the distributed ledger from FIGS. 1 to 10 has the same configuration, so the description is omitted, and FIGS. 13 and 14 are used for transaction registration processing and transaction acquisition processing, which are differences. and explain.

FIG. 13 is a flowchart showing the process of registering the transaction 401 in the distributed ledger 421 in the blockchain device 111. In this embodiment, a description will be given in which the user requests registration of the transaction 401 in the distributed ledger managed by the blockchain device 111 via the web browser of the PC 101 . However, it is also possible to execute the main registration process in cooperation with another system, and the processing form is not limited. Key information 1002 and registration data 1003 are entered on the blockchain access screen 1000, and a registration button 1005 is pressed. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 305 of the blockchain device 111 of the transaction registration processing request. At this time, both the key information 1002 and the value of the registration data 1003 input on the blockchain access screen 1000 are transmitted. The input values of the transaction registration processing request, the key information 1002 and the registration data 1003 received by the communication control unit 305 are passed to the distributed ledger management processing control unit 304 and executed by the CPU 201 .

In step S1301, the key information 1002 and registration data 1003 that have been input through the web browser of the PC 101 are obtained. In step S1302 , the distributed ledger data whose ledger type is “registration” is acquired from the distributed ledger information of Table 2 from the distributed ledger management data storage unit 303 .

In step S1303, it is determined whether or not the distributed ledger management data acquired in step S1302 exists. If it exists, the process proceeds to step S1304; otherwise, the process proceeds to step S1307.

In step S1304, the distributed ledger ID of the distributed ledger data obtained in step S1302 and the key information 1002 and registration data 1003 obtained in step S1301 are passed to the distributed ledger processing control unit 302 to request registration processing of the transaction 401. The distributed ledger processing control unit 302 creates and registers the following transaction 401 in the distributed ledger 421 having the relevant distributed ledger ID.
・Key 402: Key information 1002
・Data 403: Registration data 1003

In step S1305, an access information key is generated by assigning the registered distributed ledger ID to the key information 1002 specified at the time of registration in order to improve the efficiency of transaction processing.
Access information key = distributed ledger ID + key information 1002

In this embodiment, the access information key is explained by concatenating two pieces of data, but it is configured so that the access information key information can be concealed by processing the information if it is in a format that can be decrypted. may

In step S1306, the access information key generated in step S1305 is notified to the PC 101. In step S1307, the PC 101 is notified of an error that the distributed ledger to be registered does not exist.

FIG. 14 is a flowchart showing the process of acquiring registration data from a predetermined distributed ledger 421 in the blockchain device 111. In this embodiment, the user requests acquisition of the transaction 401 from the distributed ledger managed by the blockchain device 111 via the web browser of the PC 101 . However, it is also possible to execute the main registration process in cooperation with another system, and the processing form is not limited. Key information 1002 is entered on the blockchain access screen 1000, and an acquisition button 1006 is pressed. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 305 of the blockchain device 111 of the transaction acquisition processing request. At this time, the PC 101 also transmits the value of the key information 1002 input on the blockchain access screen 1000 . The transaction acquisition processing request received by the communication control unit 305 and the input value of the key information 1002 are passed to the distributed ledger management processing control unit 304 and executed by the CPU 201 . In this embodiment, the key information 1002 is the key information 1002 input by the user at the time of registration in step S1301 of FIG. becomes.

In step S1401, the key information 1002 input by the web browser of the PC 101 is acquired. In step S1402, the acquired key information 1002 is divided into the form of the distributed ledger ID of the access information key and the key information 1002. FIG. Then, in the next step S1403, it is determined whether or not the format of the access information key can be divided. If it can be divided, the process proceeds to step S1404, and if it cannot be divided, the process proceeds to step S1406.

In step S1404, the distributed ledger data matching the divided distributed ledger ID is acquired from the distributed ledger information in Table 2 and stored in the RAM 203. Then, in the next step S1405, it is determined whether or not the distributed ledger data has been acquired. If it can be acquired, the process advances to step S1407, and if it cannot be acquired, the process advances to step S1406.

In step S1406, from the distributed ledger group definition information in Table 1 and the distributed ledger information in Table 2, the distributed ledger data whose ledger type is "registration" or "reference" is acquired from the distributed ledger management data storage unit 303 and stored in the RAM 203. do. In step S1407, one distributed ledger data with the latest type change date is selected from the distributed ledger data acquired in step S1404 or step S1406 and stored in the RAM 203.

In step S1408, it is determined whether or not the distributed ledger data selected in step S1407 exists. In step S1409, a request is made to acquire the transaction 401. FIG. The distributed ledger ID of the distributed ledger data selected in step S1407, the key information extracted from the access information key in step S1402, or the key information 1002 obtained in step S1401 if it could not be extracted, distributed ledger processing control unit 302. Then, it requests acquisition processing of the transaction 401 . The distributed ledger processing control unit 302 searches the transaction 401 having the value of the key information 1002 in the key 402 from the distributed ledger having the relevant divided ledger ID, and passes it to the distributed ledger management processing control unit 304 if there is a match.

In step S1410, it is determined whether or not the transaction 401 acquired in step S1409 exists, and if so, the process proceeds to the next step S1411. If it does not exist, the distributed ledger data selected in step S1407 is deleted from the RAM 203 in order to search for the next distributed ledger, and then the process returns to step S1407.

In step S1411, the data 403 of the acquired transaction 401 is notified to the PC 101.

In step S1412, the PC 101 is notified that there is no transaction data that matches the specified key information 1002 and that there is an error.

After the end of this flowchart, on the screen of the PC 101, if the data 403 can be acquired, it is displayed in the registered data 1003. When an error notification is received, similar to the flow chart of FIG. 11, the content of the error is displayed in a standard dialog (not shown) of the OS or web browser.

As described above, according to Embodiment 2, in addition to Embodiment 1, an item that can identify the registered distributed ledger is provided to the user. Therefore, transactions can be searched efficiently, and performance can be improved when users use the service.

<Embodiment 3>
In this embodiment, in addition to the above-described Embodiments 1 and 2, an embodiment for managing a plurality of distributed ledger groups 431 will be described. According to the present embodiment, it is possible to manage data corresponding to the retention periods of documents that differ from one another. This embodiment will be described as a difference from the first and second embodiments, and the portions not described here are the same as those in the first or second embodiment.

FIG. 15 is a block diagram showing the software configuration of the blockchain device 111 in this embodiment. Unless otherwise specified, each processing unit is a control program stored in the ROM 204 of the blockchain device 111 . The distributed ledger data storage unit 1501, the distributed ledger processing control unit 1502, and the communication control unit 1505 are the same as the distributed ledger data storage unit 301, the distributed ledger processing control unit 302, and the communication control unit 305 in FIG. . The difference of this embodiment is that the storage and control of the distributed ledger group information held in the fixed distributed ledger management data storage unit 303 are separated.

The distributed ledger management data storage unit 1503 is a storage area that holds information for managing the distributed ledger realized in this embodiment. As with the distributed ledger data storage unit 1501, this is also stored in the HDD 205 in the form of a database, file, or the like. The distributed ledger management processing control unit 1504 is for controlling the processing for managing the distributed ledger using the data of the distributed ledger management data storage unit 1503 described above.

The group management data storage unit 1506 is a storage area that holds information for managing distributed ledger groups. This is also stored in the HDD 205 in the form of a database, file, or the like, like the distributed ledger data storage unit 1501 and the distributed ledger temporary data storage unit 1503 . The group management processing control unit 1507 is for controlling the processing for managing the distributed ledger group using the data in the group management data storage unit 1506 described above.

FIG. 16 is a diagram showing the data structure of the distributed ledger group management 1601 held by the blockchain device 111. In this embodiment, the distributed ledger group management 1601 will be described as including a plurality of distributed ledger groups 431(a) and 431(b) inside.

Table 3 is a table that stores information that constitutes the distributed ledger group management 1601, is held in the group management data storage unit 1506 described above, and is manipulated by the group management processing control unit 1507. The distributed ledger group management ID is information that uniquely represents the distributed ledger group management 1601 . The distributed ledger group management name is the name of the distributed ledger group management used to present the distributed ledger group management 1601 to the user. A URL is unique connection destination information for accessing from a user in units of distributed ledger group management.

Although this embodiment presents data for managing one distributed ledger group, it is also possible to manage multiple data with different distributed ledger group management IDs. 4A, 4B, and 4C described in Embodiment 1 also hold information in the form of Tables 4 and 5, in which information is added, in order to perform distributed ledger group management. .

Table 4 is a table that stores definition information representing the distributed ledger group 431, is held in the group management data storage unit 1506 described above, and performs data manipulation by the group management processing control unit 1507. In this embodiment, unlike the first embodiment, a plurality of distributed ledger groups 431 are managed. Therefore, in order to identify each distributed ledger group 431, the distributed ledger group management ID and the distributed ledger group ID are configured as shown in Table 1 of the first embodiment. have in addition. Since the other items are the same as those in Table 1, the description is omitted. The distributed ledger group management ID has one of the distributed ledger group management IDs in Table 3 described above, and indicates which distributed ledger group management it belongs to. The distributed ledger group ID is information that uniquely represents the distributed ledger group 431 . In this embodiment, the distributed ledger group 431 can be identified only by the distributed ledger group ID, but uniqueness may be represented by a combination with the above-described distributed ledger group management ID.

In this embodiment, there are two distributed ledger groups G-001 and G-002 with different data validity periods. G-001 is a distributed ledger group whose data valid period is set to 1 year, and G-002 is a distributed ledger group whose data valid period is set to 3 years.

Table 5 is a table that stores information representing the distributed ledger 421 that constitutes the distributed ledger group 431, which is held in the distributed ledger management data storage unit 1503 described above, and data is manipulated by the distributed ledger management processing control unit 1504. In this embodiment, since a plurality of distributed ledger groups exist, it has a distributed ledger group ID for identifying the distributed ledger section loop to which it belongs in addition to the configuration of Table 2 of the first embodiment. Since the other items have the same meanings as those in Table 2, their description is omitted.

The distributed ledger group ID is information that uniquely represents the distributed ledger group 431 to which each distributed ledger 421 belongs. In this embodiment, it can be seen that four distributed ledgers 421 belong to one of the two distributed ledger groups G-001 and G-002. In this embodiment, G-001 switches the distributed ledger 421 for each year of the data validity period. There are DL-003 of ledger type "registration", which is the registration destination of new data, and DL-002 and DL-001 of ledger type "reference", which have already been used for more than one year. DL-001 has passed its data validity period, but since the distributed ledger retention period is two years, it is maintained in a retained state. Since G-002 is a distributed ledger group with a data validity period of three years, one distributed ledger 421 is configured to store data for three years. Three years have not passed since the start of use in 2019 in 2021, so there is no ledger type that has been switched to "reference" yet. In this embodiment, G-002 is explained to switch the distributed ledger for each data validity period, but like G-001, the distributed ledger is switched every year and data for 3 years is held. It does not limit

A blockchain management screen 1700 in FIG. 17 is an example of a screen for managing the distributed ledger group management 1501, distributed ledger group 431, and distributed ledger 421 of the blockchain device 111 in this embodiment. It also provides a UI and functions for performing various operations of the blockchain device 111 . The blockchain management screen 1700 is configured as a web browser in the same manner as in the first embodiment, and the description of the standard features of the web browser, such as menus and URL displays, will be omitted.

A display area 1701 is an area for displaying the components of the management screen. Although not shown, when there are too many display contents to be displayed in the area, vertical and horizontal scroll bars are displayed so that all can be displayed. The distributed ledger group management area 1702 is an area for displaying the data configuration of the distributed ledger group management and the distributed ledger group in Tables 3 and 4 described above in a tree structure. Since the distributed ledger group management of this embodiment is GM-001, the first hierarchy of the tree displays one distributed ledger group management name. Display as multiple distributed ledger group management names. In addition, as the second layer, the name of the distributed ledger group belonging to the distributed ledger group management is displayed. The name of the displayed tree hierarchy can be selected. Input area 1703, distributed ledger group name 1704, data validity period 1705, distributed ledger retention period 1706, usage start date 1707 are input area 602, distributed ledger group name 603, data validity period 604, distributed ledger retention period 605, usage start Same as day 606 . Therefore, the description is omitted.

A group management addition button 1708 is a button for creating new distributed ledger group management data. By pressing it at any time, a standard dialog with a text input area and a confirmation button is displayed, and the distributed ledger group management name is entered. By pressing the OK button, group management information is generated by creating the following data in Table 3.
・Distributed ledger group management ID: Automatically issues a unique ID in Table 3 ・Distributed ledger group management name: Character string entered in the text input area ・URL: Automatically issues a unique URL in Table 3

After generation, the distributed ledger group management name is displayed in the first layer of the distributed ledger group management area 1702.

The add group button 1709 is a button for creating new distributed ledger group data. When the distributed ledger management group of the first layer is selected in the distributed ledger group management area 1702, it becomes a depressible state. In this state, each input area of the input area 1703 is displayed as a non-input state. By pressing after inputting a desired value in each input area, the distributed ledger group creation process described later with reference to FIG. 18 is started. When the distributed ledger group creation process ends normally, the registered distributed ledger group name is displayed in the second layer of the distributed ledger group management area 1702 . The distributed ledger switching button 1710 is a button for switching the role of the distributed ledger. The processing when this button is pressed is the same as the distributed ledger switching processing flow described in FIG. 8 of the first embodiment. The distributed ledger delete button 1711 is a button for performing a process of deleting a distributed ledger whose retention period has passed. The processing when this button is pressed is the same as the distributed ledger deletion processing flow described in FIG. 9 of the first embodiment.

FIG. 18 is a flowchart showing the process of generating the distributed ledger group 431 of the blockchain device 111 in this embodiment. In this embodiment, a procedure for a user to use the distributed ledger group generation process of the blockchain device 111 via the web browser of the PC 101 will be described. However, the processing of this flowchart does not limit, for example, scheduling and periodic execution by the blockchain device 111 . An add group button 1709 is pressed on the blockchain management screen 1700 . Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 1505 of the blockchain device 111 of the group generation processing request. The generation processing request received by the communication control unit 1505 is passed to the group management processing control unit 1507 and executed by the CPU 201 . At that time, information input to the blockchain management device 1700 is passed from the PC 101 to the blockchain device 111 . The information to be passed is the distributed ledger group name 1704, the data validity period 1705, the distributed ledger retention period 1706, the usage start date 1707, and the distributed ledger group management ID selected in the distributed ledger group management area 1702.

In step S1801, the distributed ledger group information in Table 4 that matches the distributed ledger group management ID received from the PC 101 is obtained from the group management data storage unit 1506. In step S1802, it is checked whether or not the same name as the distributed ledger group name 1704 received from the PC 101 exists in the distributed ledger group name of the distributed ledger group information acquired in step S1801. If it does not exist, the process proceeds to the next step S1803, and if it exists, the process proceeds to step S1806. In step S1803, it is checked whether or not the same validity period value as the data validity period 1705 received from the PC 101 exists in the data validity period of the distributed ledger group information acquired in step S1801. If it does not exist, the process proceeds to the next step S1804, and if it exists, the process proceeds to step S1806.

In step S1804, the distributed ledger group generation process is performed using the distributed ledger group name 1704, data validity period 1705, distributed ledger retention period 1706, usage start date 1707, and distributed ledger group management ID received from the PC 101. This processing is the same as the processing flow described in FIG. In step S1805, the result of the distributed ledger group generation process in step S1804 is notified to the PC 101 which is the process request source.

In step S1806, the PC 101 that requested the processing is notified of the failure of the group generation processing. After completing the processing of this flowchart, the PC 101 that has received the notification may display the processing result on the screen.

A blockchain access screen 1900 in FIG. 19 is an example of a screen provided by the blockchain device 111 to the user in order to execute registration and acquisition of the transaction 401 .

The blockchain access screen 1900 is configured as a web browser, and descriptions of the standard features of the web browser, such as the menus and URL display, will be omitted. To display this screen, enter the URL of the distributed ledger group management information listed in Table 3 in the address field of the web browser.

A display area 1901 is an area for displaying the components of the access screen. Although not shown, when there are too many display contents to be displayed in the area, vertical and horizontal scroll bars are displayed so that all can be displayed. Key information 1902 and registration data 1903 are the same as the key information 1002 and registration data 1003 in FIG.

The validity period 1904 is the transaction validity period specified at the time of registration, and the distributed ledger group to be stored is determined according to this period.

A registration button 1905 is a button that is activated when values are entered in the key information 1902, the registration data 1903, and the validity period 1904. By pressing the registration button 1905, registration processing of the transaction 401, which will be described later with reference to FIG. 20, is executed. . An acquisition button 1906 is a button that is activated when a value is entered in the key information 1902 described above, and executes an acquisition process of a transaction 401, which will be described later with reference to FIG. During this acquisition process, an access information key, which will be described later with reference to FIG. An update button 1907 is a button that is activated when values are displayed in the key information 1902, the registration data 1903, and the validity period 1904. By pressing this button, update processing of the transaction 401, which will be described later with reference to FIG. 22, is executed. .

FIG. 20 is a flowchart showing the process of registering the transaction 401 in the distributed ledger 421 in the blockchain device 111 of this embodiment. In this embodiment, a description will be given in which the user requests registration of the transaction 401 in the distributed ledger managed by the blockchain device 111 via the web browser of the PC 101 . However, it is also possible to execute the main registration process in cooperation with another system, and the processing form is not limited. Key information 1902, registration data 1903, and validity period 1904 are entered on the blockchain access screen 1900, and a registration button 1905 is pressed. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 1505 of the blockchain device 111 of the transaction registration processing request. The transaction registration processing request received by the communication control unit 1505 and the input values of the key information 1902, registration data 1903, and validity period 1904 are passed to the group management processing control unit 1507 and executed by the CPU 201. FIG.

In step S2001, the validity period 1904 received from the PC 101 is acquired. In step S2002, the target distributed ledger group management ID in Table 3 is acquired from the group management data storage unit 1506 from the URL that received the request. Then, the distributed ledger group information of Table 4 that matches the obtained distributed ledger group management ID is obtained from the group management data storage unit 1506 . In step S2003, the data valid period of the distributed ledger group information acquired in step S2002 is compared with the value of the valid period 1904 acquired in step S2001. If there is a matching value, the process proceeds to step S2004, and if there is no matching value, the process proceeds to step S2008.

In step S2004, the distributed ledger group ID of the distributed ledger group information that matches when compared in step S2003 is acquired. In step S2005, the key information 1902 and the registration data 1903 are passed to the distributed ledger group of the distributed ledger group ID acquired in step S2004, and the transaction 401 is registered. This processing is executed by requesting the distributed ledger management processing control unit 1504 from the group management processing control unit 1507, but since it is the same as the transaction registration processing flow described in FIG. 13 of the second embodiment, it will be omitted. After the processing ends, the generated access information key is received.

In step S2006, group information is added to the access information key received as the processing result of step S2005 to generate a new access information key.
New access information key = distributed ledger group ID + access information key received in step S2005

As a result, the access information key in this embodiment includes the following three elements.
・Distributed ledger group ID
・Distributed ledger ID
・Key information 1902

This access information key is described in this embodiment by concatenating three pieces of data, but if it is in a format that can be decrypted as in the second embodiment, information processing is performed to hide the access information key information. It may be configured to be

In step S2007, the access information key generated in step S2006 is notified to the PC 101. In step S2008, the PC 101 is notified of an error that the distributed ledger to be registered does not exist. After the end of this flowchart, the registration result and error are displayed on the screen of the PC 101. This is done using a standard dialog (not shown) possessed by the OS or web browser, and is explained in this embodiment. omitted.

FIG. 21 is a flowchart showing the process of acquiring registration data from a predetermined distributed ledger 421 in the blockchain device 111. In this embodiment, the user requests acquisition of the transaction 401 from the distributed ledger managed by the blockchain device 111 via the web browser of the PC 101 . However, it is also possible to execute the main registration process in cooperation with another system, and the processing form is not limited.

The key information 1902 is entered on the blockchain access screen 1900, and the acquire button 1906 is pressed. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 1505 of the blockchain device 111 of the transaction acquisition processing request. At this time, the PC 101 also transmits the value of the key information 1902 input on the blockchain access screen 1900 . The transaction acquisition processing request received by the communication control unit 1505 and the input value of the key information 1902 are passed to the group management processing control unit 1507 and executed by the CPU 201 . In this embodiment, the key information 1902 is the key information 1902 input by the user at the time of registration in step S2001 of FIG. becomes.

At step S2101, the key information 1902 received from the PC 101 is acquired. In step S2102 , the acquired key information 1902 is divided into a distributed ledger group ID of the access information key and an access information key format including the distributed ledger ID and the key information 1002 . Then, in the next step S2103, it is determined whether or not the format of the access information key can be divided. If it can be divided, the process advances to step S2104, and if it cannot be divided, the process advances to step S2106.

In step S2104, the target distributed ledger group management ID in Table 3 is obtained from the group management data storage unit 1506 from the URL that received the request. Then, the distributed ledger group information of Table 4 that matches the distributed ledger group management ID and the distributed ledger group ID obtained in step S2102 is obtained from the group management data storage unit 1506 and saved in the RAM 203 . In step S2105, it is determined whether distributed ledger group information has been acquired. If it can be acquired, the process proceeds to step S2107, and if it cannot be acquired, the distributed ledger group information stored in the RAM 203 is deleted, and the process proceeds to step S2106.

In step S2106, the target distributed ledger group management ID in Table 3 is obtained from the group management data storage unit 1506 from the URL that received the request. Then, all distributed ledger group information in Table 4 that matches the distributed ledger group management ID is acquired from the group management data storage unit 1506 and stored in the RAM 203 .

In step S2107, one item is acquired from the distributed ledger group information acquired in step S2104 or step S2106. Then, in step S2108, it is determined whether one distributed ledger group information has been acquired, and if it can be acquired, the process proceeds to step S2109. move on. In step S2109, a distributed ledger group ID is obtained from the distributed ledger group information obtained in step S2107. Then, when the access information key can be divided in step S2102, the transaction search processing is performed using the divided access information key. If it cannot be divided, transaction search processing is performed using one of the key information 1902 received in step S2101 and the distributed ledger group ID. Since this processing is the same as the transaction search processing described in FIG. 14 of the second embodiment, it will be omitted. Here, after the processing ends, the transaction 401 of the search result is received.

In step S2110, it is determined whether the desired transaction 401 was obtained as a result of the search in step S2109. If the transaction 401 can be acquired, the process proceeds to step S2111, and if the transaction 401 cannot be acquired, the process proceeds to step S2107 to search for the next distributed ledger group. In step S2111, the data 403 of the acquired transaction 401 is notified to the PC 101. FIG. In step S2112, the PC 101 is notified that there is no transaction data that matches the designated key information 1902.

FIG. 22 is a flowchart showing validity period update processing for a transaction whose validity period has expired in the blockchain device 111 . In the present embodiment, a description will be given in which the user requests updating of the effective period of the transaction 401 from the distributed ledger managed by the blockchain device 111 via the web browser of the PC 101 . However, it is also possible to execute the main registration process in cooperation with another system, and the processing form is not limited.

The key information 1902 is entered on the blockchain access screen 1900, and the update button 1907 is pressed. Accordingly, in this flowchart, the communication control unit 503 of the PC 101 notifies the communication control unit 1505 of the blockchain device 111 of the transaction valid period update processing request. At this time, the PC 101 also transmits the value of the key information 1902 input on the blockchain access screen 1900 . The transaction valid period update processing request and the input value of the key information 1902 received by the communication control unit 1505 are passed to the group management processing control unit 1507 and executed by the CPU 201 . In this embodiment, the key information 1902 is the key information 1902 input by the user at the time of registration in step S2001 of FIG. becomes.

The processing from step S2201 to step S2210 is the same as the processing from step S2101 to step S2110 in FIG.

In step S2211, the transaction 401 is re-registered. The key information 402 and registration data 403 of the transaction 401 acquired in step S2209 are passed to the distributed ledger group 431 having the distributed ledger group ID of the distributed ledger group information acquired in step S2207. Then, the transaction 401 is re-registered. This processing is executed by requesting the distributed ledger management processing control unit 1504 from the group management processing control unit 1507, but since it is the same as step S2005 in FIG. 20, the description is omitted in this flowchart. By this process, a new transaction is registered in the distributed ledger 421 of the ledger type "registration", and the update process is performed.

In step S2212, group information is added to the access information key received as the processing result of step S2211 to generate a new access information key. Since this process is also the same as step S2006, the description is omitted.

In step S2213, the access information key generated in step S2006 is notified to the PC 101. In step S2214, the PC 101 is notified of an error in the validity period updating process. After the end of this flowchart, the PC 101 displays the result of update processing and errors on the screen. Description is omitted.

As described above, according to Embodiment 3, in addition to Embodiments 1 and 2, a plurality of distributed ledger groups are managed, and information with different validity periods is configured to be centrally managed. , provided to the user. As a result, it becomes possible to apply it to the work of a wide range of users.

The present invention is not limited to the above embodiments, and various changes and modifications are possible without departing from the spirit and scope of the present invention. Accordingly, the following claims are included to publicize the scope of the invention.

This application claims priority based on Japanese Patent Application No. 2021-123271 filed on July 28, 2021, and the entire contents thereof are incorporated herein.

Claims

Stores multiple blockchain distributed ledgers, including a registered blockchain distributed ledger that performs new transaction registration processing and registered transaction acquisition processing, and a reference blockchain distributed ledger that performs registered transaction acquisition processing without performing new transaction registration processing a storage means for
An information processing apparatus, comprising deletion means for deleting the reference blockchain distributed ledger in response to an instruction to delete the reference blockchain distributed ledger.
The information processing device according to claim 1, wherein the hash value of the final block of the reference blockchain distributed ledger is registered as the first transaction of a blockchain distributed ledger different from the blockchain distributed ledger.
3. The method according to claim 2, further comprising registration means for registering a hash value of the final block of the reference blockchain distributed ledger as a transaction of the registered blockchain distributed ledger when deleting the reference blockchain distributed ledger. The information processing device described.
4. The plurality of blockchain distributed ledgers according to any one of claims 1 to 3, wherein each of said plurality of blockchain distributed ledgers is stored in association with valid period information of transaction data of said blockchain distributed ledger. Information processing equipment.
The storage means stores a plurality of reference blockchain distributed ledgers,
5. The information processing apparatus according to any one of claims 1 to 4, wherein said plurality of reference blockchain distributed ledgers have different effective periods of transaction data.
The storage means stores a plurality of registered blockchain distributed ledgers,
6. The information processing apparatus according to any one of claims 1 to 5, wherein the plurality of registered blockchain distributed ledgers have different effective periods of transaction data.
A control method for an information processing device,
A plurality of blockchain distributed ledgers including a registered blockchain distributed ledger that performs new transaction registration processing and registered transaction acquisition processing, and a reference blockchain distributed ledger that does not perform new transaction registration processing but performs registered transaction acquisition processing A step of storing in a storage unit of an information processing device;
A control method for an information processing device, comprising: receiving an instruction to delete a reference blockchain distributed ledger and deleting the reference blockchain distributed ledger.
8. The information processing apparatus according to claim 7, wherein a hash value of the last block of said reference blockchain distributed ledger is registered as a first transaction of a blockchain distributed ledger different from said blockchain distributed ledger. control method.
9. The method according to claim 8, further comprising, when deleting the reference blockchain distributed ledger, registering a hash value of the last block of the reference blockchain distributed ledger as a transaction of the registered blockchain distributed ledger. A control method for the described information processing apparatus.
10. The blockchain distributed ledger according to any one of claims 7 to 9, wherein each of said plurality of blockchain distributed ledgers is stored in association with validity period information of transaction data of said blockchain distributed ledger. A control method for an information processing device.
The storage means stores a plurality of reference blockchain distributed ledgers,
11. The method of controlling an information processing apparatus according to claim 7, wherein said plurality of reference blockchain distributed ledgers have different effective periods of transaction data.
The storage means stores a plurality of registered blockchain distributed ledgers,
12. The control method for an information processing apparatus according to claim 7, wherein said plurality of registered blockchain distributed ledgers have different effective periods of transaction data.