JP-7854718-B2 - Information processing systems, information processing methods, servers, blockchain nodes, and programs

Inventors

• 安土 茂亨
• 正田 英樹
• 村上 照明
• 田中 貴規

Assignees

• 株式会社chaintope

Dates

Publication Date

20260507

Application Date

20230209

Claims (7)

1. An information processing system including a server, multiple blockchain nodes, and a terminal operated by a user , When an item is traded between multiple users, the first user generates the item to be generated, and when the item is sent from the first user, who is the sender of the item to be generated, to the second user, who is the recipient of the item, In response to the operation of the first user, the terminal operated by the first user transmits to the server the following : item identification data representing the identification information of the item to be generated, raw material identification data which is the identification information of the raw materials used when generating the item to be generated, quantity data representing the quantity of the raw materials, and source item identification data representing the identification information of the source item. The aforementioned server, Based on the parameter values corresponding to the raw materials and the quantity data, the commitment value of the item to be generated is calculated by performing a secure computation using the KZG commitment, a commitment scheme that utilizes polynomials, which makes only the quantity data of some raw materials publicly available . The combination of the raw material identification data and the target item identification data is stored in a predetermined data structure. A first transaction data is obtained, which is transaction data recorded in the blockchain stored in the memory unit of the blockchain node, and in which the origin item identification data and the commitment value of the origin item are included in the output data. A second transaction data is obtained, which includes a transaction data containing an address representing the source of the item to be generated, an address representing the destination of the item to be generated, and the data structure, wherein the source item identification data is included in the input data , and the data structure containing the item to be generated and the commitment value of the item to be generated are included in the output data, and the second transaction data is broadcast to multiple blockchain nodes. Each of the multiple blockchain nodes, Each of the first transaction data, which is past transaction data associated with the second transaction data broadcast by the server, is read from the blockchain. Based on the relationship between the commitment value of the item to be generated included in the second transaction data and the commitment value of the source item included in the first transaction data, it is verified whether the item to be generated in the second transaction data is composed of the raw materials included in the source item of the first transaction data, and if it is determined that the item to be generated in the second transaction data is composed of the raw materials of the first transaction data, the second transaction data is recorded on the blockchain . When the server calculates the commitment value of the item to be generated, The commitment value of the item to be generated is calculated by adding the result of a sum-of-products operation between a blind parameter value corresponding to a blind factor that does not actually contain raw materials in the item to be generated, and blind quantity data that represents a pre-adjusted random quantity of the blind factor, to the result of a sum-of-products operation between the parameter value and the quantity data. When the plurality of blockchain nodes verify whether the item to be generated in the second transaction data is composed of the raw materials of the plurality of first transaction data, If the sum of the commitment value of the item to be generated included in the second transaction data and the commitment value corresponding to the remainder of the raw materials generated when generating the item to be generated is equal to the sum of the commitment values of the source items included in a plurality of the first transaction data, it is determined that the item to be generated in the second transaction data is composed of the raw materials from a plurality of the first transaction data. Information processing system.
2. When the server receives a request signal representing a request for disclosure of the parameter value, it performs an authentication process with the terminal that sent the request signal, and if the terminal that sent the request signal is a terminal that has been previously authorized to disclose the parameter value, it discloses the parameter value to the terminal that sent the request signal. The information processing system according to claim 1 .
3. The server in an information processing system including a server, multiple blockchain nodes, and a terminal operated by a user , When an item is traded between multiple users, the first user generates the item to be generated, and when the item is sent from the first user, who is the sender of the item to be generated, to the second user, who is the recipient of the item, In response to the operation of the first user, the terminal operated by the first user transmits to the server the following : item identification data representing the identification information of the item to be generated, raw material identification data which is the identification information of the raw materials used when generating the item to be generated, quantity data representing the quantity of the raw materials, and source item identification data representing the identification information of the source item. The aforementioned server, Based on the parameter values corresponding to the raw materials and the quantity data, the commitment value of the item to be generated is calculated by performing a secure computation using the KZG commitment, a commitment scheme that utilizes polynomials, which makes only the quantity data of some raw materials publicly available . The combination of the raw material identification data and the target item identification data is stored in a predetermined data structure. A first transaction data is obtained, which is transaction data recorded in the blockchain stored in the memory unit of the blockchain node, and in which the origin item identification data and the commitment value of the origin item are included in the output data. A second transaction data is obtained, which includes a transaction data containing an address representing the source of the item to be generated, an address representing the destination of the item to be generated, and the data structure, wherein the source item identification data is included in the input data , and the data structure containing the item to be generated and the commitment value of the item to be generated are included in the output data, and the second transaction data is broadcast to multiple blockchain nodes. Each of the multiple blockchain nodes, Each of the first transaction data, which is past transaction data associated with the second transaction data broadcast by the server, is read from the blockchain. Based on the relationship between the commitment value of the item to be generated included in the second transaction data and the commitment value of the source item included in the first transaction data, it is verified whether the item to be generated in the second transaction data is composed of the raw materials included in the source item of the first transaction data, and if it is determined that the item to be generated in the second transaction data is composed of the raw materials of the first transaction data, the second transaction data is recorded on the blockchain . When the server calculates the commitment value of the item to be generated, The commitment value of the item to be generated is calculated by adding the result of a sum-of-products operation between a blind parameter value corresponding to a blind factor that does not actually contain raw materials in the item to be generated, and blind quantity data that represents a pre-adjusted random quantity of the blind factor, to the result of a sum-of-products operation between the parameter value and the quantity data. When the plurality of blockchain nodes verify whether the item to be generated in the second transaction data is composed of the raw materials of the plurality of first transaction data, If the sum of the commitment value of the item to be generated included in the second transaction data and the commitment value corresponding to the remainder of the raw materials generated when generating the item to be generated is equal to the sum of the commitment values of the source items included in a plurality of the first transaction data, it is determined that the item to be generated in the second transaction data is composed of the raw materials from a plurality of the first transaction data. server.
4. The blockchain node in an information processing system including a server, multiple blockchain nodes, and a terminal operated by a user , When an item is traded between multiple users, the first user generates the item to be generated, and when the item is sent from the first user, who is the sender of the item to be generated, to the second user, who is the recipient of the item, In response to the operation of the first user, the terminal operated by the first user transmits to the server the following : item identification data representing the identification information of the item to be generated, raw material identification data which is the identification information of the raw materials used when generating the item to be generated, quantity data representing the quantity of the raw materials, and source item identification data representing the identification information of the source item. The aforementioned server, Based on the parameter values corresponding to the raw materials and the quantity data, the commitment value of the item to be generated is calculated by performing a secure computation using the KZG commitment, a commitment scheme that utilizes polynomials, which makes only the quantity data of some raw materials publicly available . The combination of the raw material identification data and the target item identification data is stored in a predetermined data structure. A first transaction data is obtained, which is transaction data recorded in the blockchain stored in the memory unit of the blockchain node, and in which the origin item identification data and the commitment value of the origin item are included in the output data. A second transaction data is obtained, which includes a transaction data containing an address representing the source of the item to be generated, an address representing the destination of the item to be generated, and the data structure, wherein the source item identification data is included in the input data , and the data structure containing the item to be generated and the commitment value of the item to be generated are included in the output data, and the second transaction data is broadcast to multiple blockchain nodes. Each of the multiple blockchain nodes, Each of the first transaction data, which is past transaction data associated with the second transaction data broadcast by the server, is read from the blockchain. Based on the relationship between the commitment value of the item to be generated included in the second transaction data and the commitment value of the source item included in the first transaction data, it is verified whether the item to be generated in the second transaction data is composed of the raw materials included in the source item of the first transaction data, and if it is determined that the item to be generated in the second transaction data is composed of the raw materials of the first transaction data, the second transaction data is recorded on the blockchain . When the server calculates the commitment value of the item to be generated, The commitment value of the item to be generated is calculated by adding the result of a sum-of-products operation between a blind parameter value corresponding to a blind factor that does not actually contain raw materials in the item to be generated, and blind quantity data that represents a pre-adjusted random quantity of the blind factor, to the result of a sum-of-products operation between the parameter value and the quantity data. When the plurality of blockchain nodes verify whether the item to be generated in the second transaction data is composed of the raw materials of the plurality of first transaction data, If the sum of the commitment value of the item to be generated included in the second transaction data and the commitment value corresponding to the remainder of the raw materials generated when generating the item to be generated is equal to the sum of the commitment values of the source items included in a plurality of the first transaction data, it is determined that the item to be generated in the second transaction data is composed of the raw materials from a plurality of the first transaction data. Blockchain node.
5. An information processing method performed by an information processing system including a server, multiple blockchain nodes, and a terminal operated by a user , When an item is traded between multiple users, the first user generates the item to be generated, and when the item is sent from the first user, who is the sender of the item to be generated, to the second user, who is the recipient of the item, In response to the operation of the first user, the terminal operated by the first user transmits to the server the following : item identification data representing the identification information of the item to be generated, raw material identification data which is the identification information of the raw materials used when generating the item to be generated, quantity data representing the quantity of the raw materials, and source item identification data representing the identification information of the source item. The aforementioned server, Based on the parameter values corresponding to the raw materials and the quantity data, the commitment value of the item to be generated is calculated by performing a secure computation using the KZG commitment, a commitment scheme that utilizes polynomials, which makes only the quantity data of some raw materials publicly available . The combination of the raw material identification data and the target item identification data is stored in a predetermined data structure. A first transaction data is obtained, which is transaction data recorded in the blockchain stored in the memory unit of the blockchain node, and in which the origin item identification data and the commitment value of the origin item are included in the output data. A second transaction data is obtained, which includes a transaction data containing an address representing the source of the item to be generated, an address representing the destination of the item to be generated, and the data structure, wherein the source item identification data is included in the input data , and the data structure containing the item to be generated and the commitment value of the item to be generated are included in the output data, and the second transaction data is broadcast to multiple blockchain nodes. Each of the multiple blockchain nodes, Each of the first transaction data, which is past transaction data associated with the second transaction data broadcast by the server, is read from the blockchain. Based on the relationship between the commitment value of the item to be generated included in the second transaction data and the commitment value of the source item included in the first transaction data, it is verified whether the item to be generated in the second transaction data is composed of the raw materials included in the source item of the first transaction data, and if it is determined that the item to be generated in the second transaction data is composed of the raw materials of the first transaction data, the second transaction data is recorded on the blockchain . When the server calculates the commitment value of the item to be generated, The commitment value of the item to be generated is calculated by adding the result of a sum-of-products operation between a blind parameter value corresponding to a blind factor that does not actually contain raw materials in the item to be generated, and blind quantity data that represents a pre-adjusted random quantity of the blind factor, to the result of a sum-of-products operation between the parameter value and the quantity data. When the plurality of blockchain nodes verify whether the item to be generated in the second transaction data is composed of the raw materials of the plurality of first transaction data, If the sum of the commitment value of the item to be generated included in the second transaction data and the commitment value corresponding to the remainder of the raw materials generated when generating the item to be generated is equal to the sum of the commitment values of the source items included in a plurality of the first transaction data, it is determined that the item to be generated in the second transaction data is composed of the raw materials from a plurality of the first transaction data. Information processing methods.
6. A program to be executed on a server in an information processing system including a server, multiple blockchain nodes, and a terminal operated by a user , When an item is traded between multiple users, the first user generates the item to be generated, and when the item is sent from the first user, who is the sender of the item, to the second user, who is the recipient, In response to the operation of the first user, the terminal operated by the first user transmits to the server the following : item identification data representing the identification information of the item to be generated, raw material identification data which is the identification information of the raw materials used when generating the item to be generated, quantity data representing the quantity of the raw materials, and source item identification data representing the identification information of the source item. The aforementioned server, Based on the parameter values corresponding to the raw materials and the quantity data, the commitment value of the item to be generated is calculated by performing a secure computation using the KZG commitment, a commitment scheme that utilizes polynomials, which makes only the quantity data of some raw materials publicly available . The combination of the raw material identification data and the target item identification data is stored in a predetermined data structure. A first transaction data is obtained, which is transaction data recorded in the blockchain stored in the memory unit of the blockchain node, and in which the origin item identification data and the commitment value of the origin item are included in the output data. A second transaction data is obtained, which includes a transaction data containing an address representing the source of the item to be generated, an address representing the destination of the item to be generated, and the data structure, wherein the source item identification data is included in the input data , and the data structure containing the item to be generated and the commitment value of the item to be generated are included in the output data, and the second transaction data is broadcast to multiple blockchain nodes. Each of the multiple blockchain nodes, Each of the first transaction data, which is past transaction data associated with the second transaction data broadcast by the server, is read from the blockchain. Based on the relationship between the commitment value of the item to be generated included in the second transaction data and the commitment value of the source item included in the first transaction data, it is verified whether the item to be generated in the second transaction data is composed of the raw materials included in the source item of the first transaction data, and if it is determined that the item to be generated in the second transaction data is composed of the raw materials of the first transaction data, the second transaction data is recorded on the blockchain . When the server calculates the commitment value of the item to be generated, The commitment value of the item to be generated is calculated by adding the result of a sum-of-products operation between a blind parameter value corresponding to a blind factor that does not actually contain raw materials in the item to be generated, and blind quantity data that represents a pre-adjusted random quantity of the blind factor, to the result of a sum-of-products operation between the parameter value and the quantity data. When the plurality of blockchain nodes verify whether the item to be generated in the second transaction data is composed of the raw materials of the plurality of first transaction data, If the sum of the commitment value of the item to be generated included in the second transaction data and the commitment value corresponding to the remainder of the raw materials generated when generating the item to be generated is equal to the sum of the commitment values of the source items included in a plurality of the first transaction data, it is determined that the item to be generated in the second transaction data is composed of the raw materials from a plurality of the first transaction data. program.
7. A program to be executed by a blockchain node in an information processing system including a server, multiple blockchain nodes, and a terminal operated by a user , When an item is traded between multiple users, the first user generates the item to be generated, and when the item is sent from the first user, who is the sender of the item, to the second user, who is the recipient, In response to the operation of the first user, the terminal operated by the first user transmits to the server the following : item identification data representing the identification information of the item to be generated, raw material identification data which is the identification information of the raw materials used when generating the item to be generated, quantity data representing the quantity of the raw materials, and source item identification data representing the identification information of the source item. The aforementioned server, Based on the parameter values corresponding to the raw materials and the quantity data, the commitment value of the item to be generated is calculated by performing a secure computation using the KZG commitment, a commitment scheme that utilizes polynomials, which makes only the quantity data of some raw materials publicly available . The combination of the raw material identification data and the target item identification data is stored in a predetermined data structure. A first transaction data is obtained, which is transaction data recorded in the blockchain stored in the memory unit of the blockchain node, and in which the origin item identification data and the commitment value of the origin item are included in the output data. A second transaction data is obtained, which includes a transaction data containing an address representing the source of the item to be generated, an address representing the destination of the item to be generated, and the data structure, wherein the source item identification data is included in the input data , and the data structure containing the item to be generated and the commitment value of the item to be generated are included in the output data, and the second transaction data is broadcast to multiple blockchain nodes. Each of the multiple blockchain nodes, Each of the first transaction data, which is past transaction data associated with the second transaction data broadcast by the server, is read from the blockchain. Based on the relationship between the commitment value of the item to be generated included in the second transaction data and the commitment value of the source item included in the first transaction data, it is verified whether the item to be generated in the second transaction data is composed of the raw materials included in the source item of the first transaction data, and if it is determined that the item to be generated in the second transaction data is composed of the raw materials of the first transaction data, the second transaction data is recorded on the blockchain . When the server calculates the commitment value of the item to be generated, The commitment value of the item to be generated is calculated by adding the result of a sum-of-products operation between a blind parameter value corresponding to a blind factor that does not actually contain raw materials in the item to be generated, and blind quantity data that represents a pre-adjusted random quantity of the blind factor, to the result of a sum-of-products operation between the parameter value and the quantity data. When the plurality of blockchain nodes verify whether the item to be generated in the second transaction data is composed of the raw materials of the plurality of first transaction data, If the sum of the commitment value of the item to be generated included in the second transaction data and the commitment value corresponding to the remainder of the raw materials generated when generating the item to be generated is equal to the sum of the commitment values of the source items included in a plurality of the first transaction data, it is determined that the item to be generated in the second transaction data is composed of the raw materials from a plurality of the first transaction data. program.

Description

This invention relates to an information processing system, an information processing method, a server, a blockchain node, and a program. Conventionally, technologies are known for recording item tracking information on a blockchain while reducing the amount of data associated with tracking items being moved (for example, Patent Document 1). In the technology disclosed in Patent Document 1, when a server receives a request signal containing the identification information of the item to be tracked, it retrieves from the blockchain a series of transaction data corresponding to the item's movement and a series of accumulators corresponding to the transaction data series. The server then verifies whether the identification information of the item to be tracked is stored in each accumulator in the retrieved series of accumulators and outputs the verification result. Japanese Patent Publication No. 2021-64219 This figure shows an example of the schematic configuration of the information processing system of this embodiment.This is a schematic block diagram of computers that function as individual components of an information processing system.This is an explanatory diagram illustrating the processing of the information processing system of this embodiment.This is a diagram illustrating this embodiment. The embodiments will be described in detail below with reference to the drawings. <System Configuration of the Information Processing System> Figure 1 is a block diagram of the information processing system 10 of this embodiment. As shown in Figure 1, the information processing system 10 of this embodiment is composed of a terminal 12, a server 14, and a blockchain node 16. Each device of the information processing system 10 is connected by a network 20, such as the Internet. Note that, except when describing a specific node among the multiple blockchain nodes 16A, 16B, 16C, a blockchain node will simply be referred to as "blockchain node 16." Similarly, except when describing a specific terminal among the multiple terminals 12A, 12B, 12C, ..., 12X, a terminal will simply be referred to as "terminal 12." Note that while Figure 1 shows three blockchain nodes, it may include more. Also, while Figure 1 shows four terminals, it may include more. In recent years, there has been an increasing demand for the disclosure of some of the events that occurred during the production or distribution of goods or services (hereinafter also simply referred to as "items"). For example, as evidence of efforts to address environmental issues, businesses may be required to disclose figures such as the utilization rate of renewable energy, CO2 emissions, or the recycling rate of raw materials used in the provision of an item. Currently, this type of information is often reported as a sum of corporate activities over a certain period (for example, one year). However, by adding details to individual items, that information can be considered added value for those items. Furthermore, adding details to items makes it possible to prove that those items comply with international regulations regarding their distribution. Therefore, consider a scenario where item X is transferred from one business U1 to another business U2, and business U2 manufactures a new item Y based on item X. This entire sequence of events is represented as data representing a single transaction slip. This transaction slip data is then recorded on the blockchain. Since the transaction slip data is stored in the memory units (not shown) of multiple blockchain nodes 16A, 16B, and 16C, the transaction data recorded on the blockchain becomes public. Third parties can view this transaction data. This assigns details to the item, and the entire sequence of information regarding the item's manufacture or provision becomes public. However, on the other hand, some information regarding the manufacturing or provision of an item may be kept confidential. For example, for a business that manufactures intermediate materials by mixing multiple raw materials, information regarding the mixing ratio of those raw materials is considered proprietary know-how and is likely to be kept confidential. Since this know-how is also intellectual property of each business, it is generally desirable for these businesses to avoid disclosing their intellectual property to third parties free of charge. Therefore, in the information processing system 10 of this embodiment, information regarding the quantity of raw materials contained in an item is not recorded on the blockchain. Instead, the quantity of raw materials contained in the item is kept secret while verifying that there is no fraud in the transaction of the raw materials contained in the item. Specifically, in the information processing system 10 of this embodiment, a commitment value for each item is calculated by performing a predetermined secure calculation based on quantity data representing the quantity of raw materials contained in the item