JP7354568B2 - Detection program, detection method and detection device - Google Patents

Description

The present invention relates to a detection program and the like.

Conventionally, various services have been provided using blockchain. Blockchain is a database that stores data by generating units of data called blocks and connecting the blocks in the order in which they are generated.

Smart contracts are a technology related to contracts using blockchain. By making a contract based on a smart contract, transactions between users who have signed a contract can be automated. Transaction information between users is registered in blocks of the blockchain as transactions. When using blockchain for such purposes, a mechanism is required to ensure that the blockchain has not been tampered with.

For the purpose of blockchain tampering detection, when a reference request for predetermined data is received, a hash value for the predetermined data is calculated, and a check is made to see if the calculated hash value matches the digest recorded on the blockchain. There is a conventional technique for determining this. If the hash value and digest match, it means that the blockchain has not been tampered with.

Japanese Patent Application Publication No. 2017-207979 JP2017-204706A

However, the above-mentioned conventional technology has a problem in that related transactions included in the blockchain cannot be traced.

For example, with conventional technology, it is possible to detect falsification of a blockchain, but it is difficult to detect what kind of related transactions have occurred following a certain transaction between users. Note that if transaction information that associates related transactions is registered as is every time transaction information is generated, the amount of data on the blockchain will increase.

In one aspect, the present invention aims to provide a detection program, a detection method, and a detection device that can trace related transactions included in a blockchain.

In the first proposal, the computer performs the following processing. When the first event occurs, the computer generates a first transaction corresponding to the first event and registers it in the blockchain. The computer registers first event information regarding the first event and identification information of the first transaction in a first table in association with each other. The computer associates and registers second event information regarding a second event that occurred before the first event with identification information of the first transaction in the second table. The computer identifies identification information of a second transaction registered when a second event corresponding to the second event information occurs based on the second event information and the first table, and identifies the identified identification information. and the second event information are registered in the first transaction. When the computer receives a trace request for the third event, the computer detects a transaction related to the third event based on the plurality of transactions registered in the blockchain, the first table, and the second table. .

It is possible to trace related transactions included in the blockchain.

FIG. 1 is a diagram (1) for explaining the registration process. FIG. 2 is a diagram (2) for explaining the registration process. FIG. 3 is a diagram (3) for explaining the registration process. FIG. 4 is a diagram illustrating processing for tracing transactions in the upward direction. FIG. 5 is a diagram (1) for explaining the process of tracing transactions in the downward direction. FIG. 6 is a diagram (2) for explaining the process of tracing transactions in the downward direction. FIG. 7 is a diagram showing the configuration of a system according to this embodiment. FIG. 8 is a functional block diagram showing the configuration of the detection device according to this embodiment. FIG. 9 is a diagram illustrating an example of a blockchain data structure. FIG. 10 is a diagram illustrating an example of the data structure of reference destination information. FIG. 11 is a diagram showing an example of the data structure of reference source information. FIG. 12 is a flowchart showing the registration process according to this embodiment. FIG. 13 is a flowchart showing the detection process of tracing in the upstream direction according to this embodiment. FIG. 14 is a flowchart showing the detection process of tracing in the downward direction according to this embodiment. FIG. 15 is a diagram showing an example of the hardware configuration of a computer that implements the same functions as the detection device according to this embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of a detection program, a detection method, and a detection apparatus disclosed in the present application will be described in detail below based on the drawings. Note that the present invention is not limited to this example.

The detection device according to the present embodiment executes, for example, "registration processing" and "detection processing". The registration process is a process in which when a user performs a transaction, transaction information is registered in the blockchain as a transaction. The detection process is a process of detecting and tracing transactions related to the transaction specified by the user.

An example of the registration process executed by the detection device will be described. FIGS. 1 to 3 are diagrams for explaining registration processing. Here, it is assumed that each user operates a terminal device, accesses the detection device, and performs transaction A, transaction B, and transaction C in order. A transaction is an example of an "event."

FIG. 1 will be explained. When the user (Ken) performs "transaction A", a screen 10A is displayed on the terminal device. For example, assume that transaction A is a transaction for registering teacher data to be used in deep learning. The user (Ken) refers to the screen 10A, operates the terminal device, and inputs the user ID "US001" and the resource ID "data0001." The user ID is information that uniquely identifies the user (Ken). The resource ID is information that uniquely identifies teacher data.

The detection device has a blockchain 140a, and the blockchain 140a is separated from the world state 140b. Block chain 140a includes block (1). It is assumed that the hash value of the immediately preceding block (not shown) and transactions Tx1 and Tx2 have already been registered in block (1). Upon receiving input of information regarding transaction A from the terminal device, the detection device generates transaction Tx3. The detection device registers each transaction in block (1) when transactions to be registered in block (1) are accumulated.

Transaction Tx3 includes an area Tx3-a and an area Tx3-b, which are separated from each other. The detection device registers the user ID "US001" and the resource ID "data0001" input on the screen 10A in the area Tx3-a. Since "transaction A" is the first transaction, the detection device registers the original transaction ID "NULL" in area Tx3-b. The detection device registers the key "US001+data0001", which is a combination of the user ID "US001" and the resource ID "data0001" input on the screen 10A, in the area Tx3-b. Note that the detection device may set the original transaction ID to "NULL" when the original data is "none". This key "US001+data0001" can be said to be transaction information that allows identification of the transaction target and the user who conducted the transaction. A key that is a combination of another user ID and another resource ID, which will be described below, is also transaction information that can identify the transaction target and the user who has conducted the transaction.

The detection device has a world state 140b, and the world state 140b has reference destination information 141 and reference source information 142. The reference destination information 141 is information that associates transaction information with a transaction in which the transaction information is recorded. For example, the information for transaction A is "US001+data0001", which is a combination of the user ID "US001" and the resource ID "data0001" input on the screen 10A. Since the information on transaction A was registered in the blockchain 140a as transaction Tx3, the detection device registers a record in which "US001+data0001" and "Tx3" are associated with each other in reference destination information 141.

The reference source information 142 is information that associates the reference source transaction information referred to when performing a certain transaction with the transaction in which the current transaction information is recorded. Regarding transaction A, since there is no information on the transaction of the reference source, nothing is registered in the reference source information 142.

Moving on to the explanation of FIG. For example, the detection device connects block (2) to block (1) in blockchain 140a, and registers the hash value of block (1) in block (2). It is also assumed that transaction Tx4 is registered in block (2). By registering the hash value of block (1) in block (2), falsification of transactions Tx1 to Tx3 of block (1) is prevented.

When the user (Mike) performs "transaction B", a screen 10B is displayed on the terminal device. For example, assume that transaction B is a transaction for purchasing the teacher data registered in transaction A. The user (Mike) refers to the screen 10B, operates the terminal device, and inputs the user ID "US002" and the resource ID "data0001."

Further, the user (Mike) inputs information on the original data to be purchased on the screen 10B. The information on the original data includes an original user ID that uniquely identifies a user corresponding to the original data, and an original resource ID that uniquely identifies the original data. When the user (Mike) purchases the registered teacher data in transaction A, he inputs the former user ID "US001" and the former resource ID "data0001" on the screen 10B.

When the detection device receives input of information regarding transaction B from the terminal device, it generates transaction Tx5 and registers it in block (2). Transaction Tx5 includes an area Tx5-a and an area Tx5-b. The detection device registers the user ID "US002" and the resource ID "data0001" input on the screen 10B in the area Tx5-a. The detection device also registers the former user ID "US001" and the former resource ID "data0001" input on the screen 10B in the area Tx5-a.

The detection device generates a key "US001+data0001" that is a combination of the former user ID "US001" and the former resource ID "data0001" on the screen 10B, searches the reference information 141 using the generated key, and searches the reference destination information 141 to find the transaction ID. Detect “Tx3”. The detection device registers the detected transaction ID "Tx3" as the original transaction ID of area Tx5-b. Furthermore, the detection device registers the key "US002+data0001", which is a combination of the user ID "US002" and the resource ID "data0001" on the screen 10B, in the area Tx5-b.

The detection device registers the transaction B information in the reference destination information 141 in association with the transaction in which the transaction B information is recorded. The information for transaction B is "US002+data0001", which is a combination of the user ID "US002" and the resource ID "data0001" input on the screen 10B. Since the information on transaction B was registered in the blockchain 140a as transaction Tx5, the detection device registers a record in which "US002+data0001" and "Tx5" are associated with each other in reference destination information 141.

Transaction B is a transaction that uses the information of transaction A as a reference source. The information on transaction A is "US001+data0001", and the transaction ID in which the information on current transaction B is recorded is "Tx5". For example, the detection device uses the former user ID and the former resource ID input on the screen 10B as information on the reference transaction (transaction A). The detection device registers the reference source transaction A information “US001+data0001” and the transaction ID “Tx5” in the reference source information 142 in association with each other.

Although the description is omitted, the detection device registers block (2) in the blockchain 140a when transactions Tx6 and Tx7 are accumulated based on other transaction information after registering the transaction Tx5 in the blockchain 140a. .

Moving on to the explanation of FIG. For example, the detection device connects block (3) to block (2) in blockchain 140a, and registers the hash value of block (2) in block (3). By registering the hash value of block (2) in block (3), falsification of transactions Tx4 to Tx7 of block (2) is prevented.

When the user (Mike) performs "transaction C", a screen 10C is displayed on the terminal device. For example, assume that transaction C is a transaction in which a learning model is generated using the teacher data purchased in transaction B. The user (Mike) refers to the screen 10C, operates the terminal device, and inputs the user ID "US002" and the resource ID "mdl0001." The resource ID "mdl0001" is information that uniquely identifies the learning model.

Further, the user (Mike) inputs information on the original data used in learning the learning model to the screen 10C. When using the teacher data purchased in transaction B, the user (Mike) operates the terminal device and inputs the original user ID "US002" and the original resource ID "data0001" on the screen 10C.

When the detection device receives input of information regarding transaction C from the terminal device, it generates transaction Tx9 and registers it in block (3). Transaction Tx9 includes an area Tx9-a and an area Tx9-b. The detection device registers the user ID "US002" and the resource ID "mdl0001" input on the screen 10C in the area Tx9-a. The detection device registers the former user ID "US001" and the former resource ID "data0001" input on the screen 10C in the area Tx9-a.

The detection device generates a key "US002+data0001" that is a combination of the former user ID "US002" and the former resource ID "data0001" on the screen 10C, searches the reference information 141 using the generated key, and searches the reference destination information 141 to find the transaction ID. Detect “Tx5”. The detection device registers the detected transaction ID "Tx5" as the original transaction ID of area Tx9-b. The detection device also registers a key "US002+mdl0001", which is a combination of the user ID "US002" and the resource ID "mdl0001" on the screen 10C, in the area Tx9-b.

The detection device registers the transaction C information in the reference destination information 141 in association with the transaction in which the transaction C information is recorded. Information on transaction C is information "US002+mdl0001" which is a combination of user ID "US002" and resource ID "mdl0001" input on screen 10C. Since the information on transaction C was registered in the blockchain 140a as transaction Tx9, the detection device registers a record in which "US002+mdl0001" and "Tx9" are associated with each other in the reference destination information 141.

Transaction C is a transaction that uses the information of transaction B as a reference source. The information on transaction B is "US002+data0001", and the transaction ID in which the information on current transaction C is recorded is "Tx9". For example, the detection device uses the former user ID and the former resource ID input on the screen 10C as information on the reference transaction (transaction B). The detection device registers the reference source transaction B information “US001+data0001” and the transaction ID “Tx9” in the reference source information 142 in association with each other.

Although the description will be omitted, the detection device registers block (3) in the blockchain 140a when transactions Tx10 are accumulated based on other transaction information after registering the transaction Tx9 in the blockchain 140a. Furthermore, the detection device calculates the hash value of block (3) and registers the calculated hash value in subsequent blocks, thereby suppressing falsification of transactions Tx8 to Tx10.

Next, an example of a detection process executed by the detection device will be described. FIG. 4 is a diagram illustrating processing for tracing transactions in the upward direction. 5 and 6 are diagrams for explaining the process of tracing transactions in the downward direction.

FIG. 4 will be explained. For example, a user operates a terminal device, inputs a user ID "US002" and a resource ID "mdl0001" as search keys, and makes a trace request. When the detection device receives a trace request from the terminal device, it compares the search key “US002+mdl0001” with the reference destination information 141 and detects the transaction ID “Tx9”.

The detection device refers to area Tx9-b of transaction Tx9 included in blockchain 140a. The detection device determines whether the key "US002+mdl0001" recorded in the reference destination information 141 matches the key in the area Tx9-b. If the key “US002+mdl0001” recorded in the reference destination information 141 does not match the key in area Tx9-b, the detection device determines that the reference destination information 141 has been tampered with and performs the tracing process. finish.

If the key "US002+mdl0001" recorded in the reference destination information 141 matches the key in the area Tx9-b, the detection device continues the tracing process. The detection device identifies transaction Tx5 based on the original transaction ID "Tx5" of area Tx9-b. The detection device refers to area Tx5-b of transaction Tx5 and identifies transaction Tx3 based on the original transaction ID "Tx3." The detection device ends the tracing process because the original transaction ID of area Tx3-b of transaction Tx3 is "NULL".

By executing the above processing, the detection device can detect a chain of transactions in the upstream direction starting from transaction Tx9. The detection device transmits the trace result of the upstream transaction to the terminal device. The trace results of the upstream transactions are transactions Tx9, Tx5, and Tx3.

FIG. 5 will be explained. For example, a user operates a terminal device, inputs a user ID "US0001" and a resource ID "data0001" as search keys, and makes a trace request. When the detection device receives the trace request from the terminal device, it compares the search key “US001+data0001” with the reference destination information 141 to identify the transaction ID “Tx3” (step S10).

On the other hand, the detection device compares the search key "US001+data0001" with the reference source information 142 and identifies the transaction ID "Tx5" (step S11).

The detection device compares the original transaction ID "Tx3" of the area Tx5-b of the transaction Tx5 specified in step S11 with the transaction ID specified in step S10, and determines whether they match. If the original transaction ID of the area Tx5-b and the transaction identified in step S10 do not match, the detection device determines that the reference destination information 141 or the reference source information 142 has been tampered with, and ends the tracing process. do.

If the original transaction ID "Tx3" of area Tx5-b matches the transaction ID identified in step S10, the detection device identifies the relationship from transaction Tx3 to transaction Tx5.

Next, FIG. 6 will be explained. When the detection device identifies the relationship from transaction Tx3 to transaction Tx5, it refers to area Tx5-b of transaction Tx5 (step S20). The detection device compares the key "US002+data0001" of the area Tx5-b with the reference source information 142 and identifies the transaction ID "Tx9" (step S21).

The detection device compares the original transaction ID "Tx5" of the area Tx9-b of the transaction Tx9 identified in step S21 with the ID of the transaction referenced in step S20, and determines whether they match (step S22 ). If the source transaction ID "Tx5" of the area Tx9-b of the transaction Tx9 identified in step S21 does not match the ID of the transaction referenced in step S20, the detection device determines that the reference source information 142 has been tampered with. It is determined that this is the case, and the trace processing is terminated.

If the original transaction ID "Tx5" of area Tx9-b of transaction Tx9 identified in step S21 matches the transaction ID referenced in step S20, the detection device detects the relationship from transaction Tx5 to transaction Tx9. Identify.

By executing the above processing, the detection device can detect a chain of transactions in the downward direction starting from transaction Tx3. The detection device transmits the trace result of the downstream transaction to the terminal device. The trace results of the downward transactions are transactions Tx3, Tx5, and Tx9.

As described above, each time a transaction occurs, the detection device according to the present embodiment transmits information on the transaction, information on the previous transaction referred to at the time of the transaction, and information on the transaction generated in the previous transaction to the blockchain 140a, the world Each is registered in the state 140b. When performing tracing, the detection device detects related transactions using information registered in the blockchain 140a and world state 140b. This allows related transactions contained in the blockchain to be traced.

Next, an example of a system including the terminal device and detection device described in FIGS. 1 to 6 will be described. FIG. 7 is a diagram showing the configuration of a system according to this embodiment. As shown in FIG. 7, this system includes terminal devices 20a, 20b, 20c and detection devices 100a, 100b, 100c, 100d. The detection devices 100a to 100d are connected to each other. The terminal devices 20a to 20c and the detection devices 100a to 100d are connected via a network 50. In the following description, the terminal devices 20a to 20c will be collectively referred to as the terminal device 20, unless otherwise specified. The detection devices 100a to 100d are collectively referred to as a detection device 100.

The terminal device 20 is a terminal device used by a user who performs each transaction. For example, when the terminal device 20 receives information indicating that a transaction has occurred through a user's operation, it displays the screens 10A to 10C shown in FIGS. 1 to 3. The user operates the terminal device 20 to input a user ID, resource ID, former user ID, former resource ID, and the like. The terminal device 20 transmits information input by the user to the detection device 100. The pair of user ID and resource ID and the pair of former user ID and former resource ID each correspond to event information.

Further, when tracing a transaction, the user operates the terminal device 20 and inputs various information regarding the trace request. The terminal device 20 transmits trace request information to the detection device 100. The trace request information includes a user ID that serves as a search key and a resource ID. Further, the trace request information includes information indicating whether to perform upstream tracing or downstream tracing.

Every time a transaction occurs, the detection device 100 registers the transaction information, the previous transaction information referred to at the time of the transaction, and the transaction information generated in the previous transaction in the blockchain 140a and the world state 140b, respectively. When the detection device 100 receives the trace request information, it detects a related transaction using the information registered in the blockchain 140a and the world state 140b.

Next, an example of the configuration of the detection device 100 according to the present embodiment will be described. Here, the configuration of the detection device 100a will be described as an example, but the configurations of the detection devices 100b to 100d are similar to the detection device 100a.

FIG. 8 is a functional block diagram showing the configuration of the detection device according to this embodiment. As shown in FIG. 8, this detection device 100a includes a communication section 110, a storage section 140, and a control section 150. Although not shown, the detection device 100 may be connected to an input device for inputting various types of information and a display device for displaying various types of information.

The communication unit 110 is a processing unit that performs data communication with the terminal device 20 via the network 50. A control unit 150, which will be described later, exchanges data with the terminal device 20 via the communication unit 110. Communication unit 110 corresponds to a communication device.

The storage unit 140 includes a blockchain 140a and a world state 140b. The storage unit 140 corresponds to a semiconductor memory element such as a RAM (Random Access Memory) or a flash memory, or a storage device such as an HDD (Hard Disk Drive).

The blockchain 140a is a database in which a plurality of blocks are connected. FIG. 9 is a diagram illustrating an example of a blockchain data structure. As shown in FIG. 9, the blockchain 140a associates block IDs with block information. Block ID is information that uniquely identifies a block. Block information is information about the block identified by the block ID.

Each block information of the blockchain 140a includes a hash value, a transaction ID, and transaction information. The hash value is the hash value of the immediately previous block information. The transaction ID is information that uniquely identifies a transaction. The transaction information is information on the transaction identified by the transaction ID.

Each transaction information of the blockchain 140a includes a user ID, resource ID, original transaction ID, and key. The user ID and resource ID are information that is input on the screen of the terminal device when a transaction occurs. The original transaction ID is information that uniquely identifies an upstream transaction. The key is information that is a combination of a user ID and a resource ID. This key can be said to be transaction information that can identify the object of the transaction and the user who conducted the transaction.

The world state 140b has reference destination information 141 and reference source information 142. The reference destination information 141 corresponds to the "first table", and the reference source information 142 corresponds to the "second table". FIG. 10 is a diagram illustrating an example of the data structure of reference destination information. As shown in FIG. 10, this reference information 141 associates a reference key with a transaction ID. The reference key is information that is a combination of the user ID and resource ID that are input on the screen when a transaction occurs. The transaction ID is information that uniquely identifies the transaction corresponding to the transaction.

FIG. 11 is a diagram showing an example of the data structure of reference source information. As shown in FIG. 11, this reference source information 142 associates a reference source key with a transaction ID. The reference source key is information that is a combination of the original user ID and the original resource ID that are input on the screen when a transaction that refers to a transaction of a certain reference source occurs. The transaction ID is information that uniquely identifies the transaction corresponding to the transaction.

Moving on to the description of FIG. The control unit 150 includes a registration unit 150a, a detection unit 150b, and a synchronization unit 150c. The control unit 150 can be realized by a CPU (Central Processing Unit), an MPU (Micro Processing Unit), or the like. Further, the control unit 150 can also be realized by hardwired logic such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

The registration unit 150a is a processing unit that executes the registration process described in FIGS. 1 to 3. First, the processing of the registration unit 150a when the first transaction occurs will be described. When the first transaction occurs, the registration unit 150a obtains the user ID and resource ID input on the screen of the terminal device 20, and generates a transaction. The registration unit 150a registers the transaction ID and transaction information of the generated transaction in the block information of the blockchain 140a. The registration unit 150a registers a user ID, a resource ID, the original transaction "NULL", and a key that is a combination of the user ID and resource ID as transaction information.

Further, the registration unit 150a registers a key (reference destination key) that is a combination of the user ID and resource ID, and the generated transaction ID in the reference destination information 141.

For example, as described with reference to FIG. 1, upon acquiring the user ID "US001" and the resource ID "data0001" input on the screen 10A, the registration unit 150a generates the transaction Tx3. The registration unit 150a registers the user ID "US001", the resource ID "data0001", the original transaction "NULL", and the key "US001+data0001" as information on the transaction Tx3. This key "US001+data0001" can be said to be transaction information that allows identification of the transaction object "data0001" and the user "US001" who conducted the transaction.

The registration unit 150a associates the reference destination key “US001+data0001” with the transaction ID “Tx3” and registers them in the reference destination information 141.

Next, a description will be given of the processing performed by the registration unit 150a when a transaction that refers to a previous transaction occurs. The registration unit 150a acquires the user ID, resource ID, former user ID, and former resource ID input on the screen of the terminal device 20, and generates a transaction. The registration unit 150a registers the transaction ID and transaction information of the generated transaction in the block information of the blockchain 140a. The registration unit 150a registers a user ID, a resource ID, and a key that is a combination of the user ID and the resource ID as transaction information.

The registration unit 150a registers a key (reference destination key) that is a combination of a user ID and a resource ID, and the generated transaction ID in the reference destination information 141. Further, the registration unit 150a registers a key (reference source key) that is a combination of the former user ID and the original resource ID, and the generated transaction ID in the reference source information 142.

The registration unit 150a identifies a transaction ID based on a key that is a combination of the original user ID and the original resource ID, and the reference destination information 141, and adds the identified transaction ID to the transaction information as the original transaction ID. register.

For example, as explained in FIG. 2, the registration unit 150a inputs the user ID "US002" inputted on the screen 10B, the resource ID "data0001", the former user ID "US001", and the former resource ID "data0001". When acquired, transaction Tx5 is generated. The registration unit 150a registers the user ID "US002", the resource ID "data0001", and the key "US002+data0001" as information on the transaction Tx5.

The registration unit 150a associates a reference key "US002+data0001", which is a combination of a user ID "US002" and a resource ID "data0001", with a transaction ID "Tx5" and registers them in the reference information 141. The registration unit 150a associates the reference source key "US001+data0001" which is a combination of the former user ID "US001" and the former resource ID "data0001" with the transaction ID "Tx5" and registers it in the reference source information 142. do.

The registration unit 150a compares the key "US001+data0001", which is a combination of the former user ID "US001" and the former resource ID "data0001", with the reference destination information 141, and specifies the transaction ID "Tx3". The registration unit 150a registers the specified transaction ID "Tx3" as the original transaction ID in transaction Tx5.

The registration unit 150a repeatedly executes the above process based on the information input on the screen every time a new transaction occurs.

By the way, the registration unit 150a generates block information at regular intervals and registers it in the blockchain 140a. The registration unit 150a calculates the hash value of the immediately preceding block information, and registers the calculated hash value in the generated block information.

The detection unit 150b is a processing unit that executes the detection processing described in FIGS. 4 to 7. First, a process in which the detection unit 150b traces transactions in the upstream direction will be described. The detection unit 150b acquires the trace request information from the terminal device 20, and identifies the transaction ID corresponding to the search key based on the search key included in the trace request information and the reference information 141.

The detection unit 150b determines whether the search key matches the key registered in the transaction with the specified transaction ID (current transaction). If the key registered in the transaction and the search key do not match, the detection unit 150b determines that the current transaction has been tampered with, and sends information to the terminal device 20 that the transaction has been tampered with. Send.

On the other hand, if the key registered in the current transaction and the search key match, the detection unit 150b determines that the transaction has not been tampered with. If the transaction has not been tampered with, the detection unit 150b associates the current transaction with the transaction corresponding to the original transaction ID registered in the current transaction. Further, the detection unit 150b identifies the transaction with the original transaction ID, and further associates each transaction by repeatedly performing a process of tracing the transaction with the original transaction ID registered in the identified transaction.

For example, as described in FIG. 4, upon receiving the search key "US002+mdl001", the detection unit 150b compares the search key with the reference destination information 141 to identify the transaction ID "Tx9". Since the key "US002+mdl001" of transaction Tx9 and the search key "US002+mdl001" match, the detection unit 150b determines that transaction Tx9 has not been tampered with. The detection unit 150b associates transaction Tx9 and transaction Tx5 based on the original transaction ID "Tx5" of transaction Tx9. The detection unit 150b also associates the transaction Tx5 with the transaction Tx3 based on the original transaction ID "Tx3" of the transaction Tx.

By executing the above process, the detection unit 150b can detect a chain of transactions in the upstream direction starting from transaction Tx9. The detection unit 150b transmits the trace result of the upstream transaction to the terminal device. The trace results of the upstream transactions are transactions Tx9, Tx5, and Tx3.

Next, a process in which the detection unit 150b traces transactions in the downstream direction will be described. The detection unit 150b acquires trace request information from the terminal device 20, and based on the search key included in the trace request information and the reference destination information 141, detects the transaction ID (reference destination ID) corresponding to the search key. ).

The detection unit 150b identifies the transaction ID (reference source ID) corresponding to the search key based on the search key and the reference source information 142, and identifies the source registered in the transaction (current transaction) with the reference source ID. Identify the transaction ID. The detection unit 150b determines whether the reference ID and the original transaction ID match.

If the reference ID and the original transaction ID do not match, the detection unit 150b determines that the current transaction has been tampered with, and sends information to the terminal device 20 that the transaction has been tampered with. .

On the other hand, if the reference destination ID and the original transaction ID match, the detection unit 150b determines that the current transaction has not been tampered with. The detection unit 150b associates the transaction of the reference source ID with the transaction of the reference destination ID.

For example, as described in FIG. 5, upon receiving the search key "US001+data0001", the detection unit 150b compares the search key with the reference destination information 141 to identify the reference destination ID "Tx3". The detection unit 150b compares the search key with the reference source information 142 and identifies the reference source ID "Tx5." The detection unit 150b determines that the transaction Tx5 has not been tampered with since the original transaction ID "Tx3" of the transaction Tx5 with the reference source ID "Tx5" matches the reference destination ID "Tx3". The detection unit 150b associates the transaction with the reference ID "Tx5" with the transaction with the reference ID "Tx3".

Subsequently, the detection unit 150b identifies the transaction ID (next reference source ID) based on the key registered in the transaction of the reference source ID and the reference source information 142. The detection unit 150b determines whether the transaction ID stored in the transaction of the reference source ID matches the previous reference source ID. If the transaction ID stored in the transaction with the reference ID does not match the previous reference ID, the detection unit 150b determines that the transaction with the reference ID has been tampered with, and determines that the transaction has not been tampered with. The terminal device 20 sends information indicating that the

On the other hand, if the transaction ID stored in the transaction with the reference source ID matches the previous reference source ID, the detection unit 150b determines that the transaction has not been tampered with. The detection unit 150b associates the transaction of the reference source ID with the transaction of the previous reference source ID. The detection unit 150b repeatedly executes the above process.

For example, as described in FIG. 6, the detection unit 150b identifies the next reference source ID "Tx9" based on the original transaction ID "Tx3" of the transaction Tx5 and the reference source information 142. The detection unit 150b determines that the transaction Tx9 has not been tampered with since the original transaction ID "Tx" of the transaction Tx with the reference source ID "Tx9" matches the previous reference source ID "Tx5". . The detection unit 150b associates transaction Tx5 and transaction Tx9.

By executing the above process, the detection unit 150b can detect a chain of transactions in the downward direction starting from transaction Tx3. The detection unit 150b transmits the trace result of the downstream transaction to the terminal device 20. The trace results of the downward transactions are transactions Tx3, Tx5, and Tx9.

The synchronization unit 150c is a processing unit that executes synchronization processing of the blockchain 140a and world state 140b registered in the storage unit 140 with the detection devices 100b to 100d connected to the detection device 100a. The synchronization unit 150c may perform the synchronization process periodically, or may perform the synchronization process when the blockchain 140a is updated.

Next, an example of the processing procedure of the detection device 100 according to this embodiment will be described. FIG. 12 is a flowchart showing the registration process according to this embodiment. The detection device 100 performs the processing shown in FIG. 12 for each transaction. When associating N transactions, the registration process is executed N times. As shown in FIG. 12, when the next transaction occurs, the registration unit 150a of the detection device 100 records the combination of the user ID and resource ID input on the screen of the terminal device 20, the former user ID and the former resource ID. (step S101). The registration unit 150a generates a transaction and registers a key (user ID+resource ID) in the transaction (step S102).

The registration unit 150a identifies the original transaction ID based on the key (user ID+resource ID) and the reference information 141, and registers it in the transaction (step S103). The registration unit 150a registers the key (former user ID+former resource ID) and transaction ID in association with each other in the reference source information 142 (step S104).

FIG. 13 is a flowchart showing the detection process of tracing in the upstream direction according to this embodiment. As shown in FIG. 13, the detection unit 150b of the detection device 100 receives an uplink trace request from the terminal device 20 (step S201). The detection unit 150b identifies the transaction ID based on the search key and the reference information 141 (step S202).

The detection unit 150b determines whether the key registered in the transaction corresponding to the transaction ID matches the search key (step S203). If the key and the search key do not match (step S204, No), the detection unit 150b determines that the transaction has been tampered with (step S205), and proceeds to step S211.

On the other hand, if the key and the search key match (step S204, Yes), the detection unit 150b moves to step S206. The detection unit 150b identifies the original transaction ID of the current transaction (step S206). The detection unit 150b associates the current transaction with the transaction of the original transaction ID (step S207).

The detection unit 150b sets the transaction with the original transaction ID as the current transaction (step S208). The detection unit 150b determines whether the original transaction ID of the current transaction is "NULL" (step S209). If the original transaction ID is not "NULL" (step S210, No), the detection unit 150b moves to step S206.

If the original transaction ID is "NULL" (step S210, Yes), the detection unit 150b outputs the detection result to the terminal device 20 (step S211).

FIG. 14 is a flowchart showing the detection process of tracing in the downward direction according to this embodiment. As shown in FIG. 14, the detection unit 150b of the detection device 100 receives a downlink trace request from the terminal device 20 (step S301). The detection unit 150b identifies the transaction ID (reference ID) based on the search key and the reference information 141 (step S302).

The detection unit 150b identifies the transaction ID (reference source ID) based on the search key and the reference source information 142 (step S303). The detection unit 150b determines whether the original transaction ID registered in the transaction corresponding to the reference source ID and the reference destination ID match (step S304). If the original transaction ID and the reference ID do not match (step S305, No), the detection unit 150b determines that the transaction has been falsified (step S306).

On the other hand, if the original transaction ID and the reference ID match (step S305, Yes), the detection unit 150b moves to step S307. The detection unit 150b associates the transaction of the reference source ID with the transaction of the reference destination ID (step S307).

The detection unit 150b identifies the transaction ID (next reference source ID) based on the key registered in the transaction of the reference source ID and the reference source information 142 (step S308). The detection unit 150b determines whether or not the original transaction ID of the transaction corresponding to the reference source ID matches the previous reference source ID (step S309).

If the original transaction ID and the previous reference source ID do not match (step S310, No), the detection unit 150b moves to step S306. If the original transaction ID and the previous reference ID match (step S310, Yes), the detection unit 150b detects the transaction corresponding to the current reference ID and the previous reference ID. Corresponding transactions are associated (step S311).

The detection unit 150b determines whether the key registered in the transaction of the current reference source ID is registered in the reference source information 142 (step S312). If the key registered in the transaction of the current reference source ID is registered in the reference source information 142 (step S313, Yes), the detection unit 150b moves to step S308.

On the other hand, if the key registered in the transaction with the current reference source ID is not registered in the reference source information 142 (step S313, No), the detection unit 150b outputs the detection result to the terminal device 20 ( Step S314).

Next, the effects of the detection device 100 according to this embodiment will be explained. Every time a transaction occurs, the detection device 100 registers information on the transaction that has occurred, information on the referenced previous transaction, and transaction ID of the previous transaction in the blockchain 140a and the world state 140b. Upon receiving the trace request, the detection device 100 detects a transaction related to the transaction corresponding to the search key based on the blockchain 140a and the world state 140b, and performs tracing. This makes it possible to trace related transactions included in the blockchain 140a.

When the detection device 100 receives a trace request, the detection device 100 identifies the transaction ID based on the search key and the reference destination information 141. When the key registered in the transaction corresponding to the transaction ID and the search key match, the detection device 100 associates the transaction with the transaction with the original transaction ID registered in the transaction. This makes it possible to detect the results of tracing a transaction guaranteed to be tampered in the upstream direction.

When the detection device 100 receives a trace request, the detection device 100 identifies the reference source ID based on the search key and the reference source information 142, and identifies the original transaction ID registered in the transaction of the reference source ID. When the source transaction ID and the reference destination ID specified from the search key and the reference destination information 141 match, the detection device 100 associates the transaction with the reference source ID and the transaction with the reference destination ID. This makes it possible to detect the results of tracing a transaction guaranteed to be tampered in the downward direction.

The detection device 100 determines that the transaction has not been tampered with if the transaction ID stored in the transaction of the reference source ID matches the previous reference source ID. Then, the detection device 100 associates the transaction of the reference source ID with the transaction of the previous reference source ID. This makes it possible to detect the results of tracing a transaction guaranteed to be tampered in the downward direction.

Since the detection device 100 only registers the user ID, resource ID, and transaction ID in the transaction, reference destination information 141, and reference source information 142 as information for tracing, the data size can be reduced. Further, since the information to be traced is small, the amount of information scanned by the detection device 100 can be reduced, and processing speed and real-time performance can be improved.

Next, an example of the hardware configuration of a computer that implements the same functions as the detection device 100 shown in this embodiment will be described. FIG. 15 is a diagram showing an example of the hardware configuration of a computer that implements the same functions as the detection device according to this embodiment.

As shown in FIG. 15, the computer 300 includes a CPU 301 that executes various calculation processes, an input device 302 that accepts data input from a user, and a display 303. The computer 300 also includes a reading device 304 that reads programs and the like from a storage medium, and an interface device 305 that exchanges data with an external device or the like via a wired or wireless network. Computer 300 includes a RAM 306 that temporarily stores various information and a hard disk drive 307. Each device 301 to 307 is then connected to a bus 308.

The hard disk device 307 has a registration program 307a, a detection program 307b, and a synchronization program 307c. The CPU 301 reads the registration program 307a, the detection program 307b, and the synchronization program 307c and expands them into the RAM 306.

Registration program 307a functions as registration process 306a. The detection program 307b functions as a detection process 306b. The synchronization program 307c functions as a synchronization process 306c.

The processing of the registration process 306a corresponds to the processing of the registration unit 150a. The processing of the detection process 306b corresponds to the processing of the detection unit 150b. The processing of the synchronization process 306c corresponds to the processing of the synchronization unit 150c.

Note that each of the programs 307a to 307c does not necessarily need to be stored in the hard disk drive 307 from the beginning. For example, each program is stored in a "portable physical medium" such as a flexible disk (FD), CD-ROM, DVD disk, magneto-optical disk, or IC card that is inserted into the computer 300. Then, the computer 300 may read and execute each program 307a to 307c.

Regarding the embodiments including each of the above examples, the following additional notes are further disclosed.

(Additional note 1) On the computer,
If a first event occurs, generate a first transaction corresponding to the first event and register it on the blockchain;
registering first event information regarding the first event and identification information of the first transaction in a first table;
registering second event information regarding a second event that occurred before the first event and identification information of the first transaction in a second table;
identifying identification information of a second transaction registered when a second event corresponding to the second event information occurs based on the second event information and the first table; and identifying the identified identification information. and the second event information in the first transaction,
When a trace request for a third event is received, a transaction related to the third event is detected based on the plurality of transactions registered in the blockchain, the first table, and the second table. A detection program characterized by causing a process to be executed.

(Additional note 2) The detecting process identifies and identifies a transaction having identification information corresponding to the third event information based on the third event information regarding the third event and the first table. Supplementary Note 1, characterized in that when the event information registered in the transaction and the third event information match, the specified transaction is associated with the transaction corresponding to the identification information registered in the specified transaction. detection program.

(Supplementary Note 3) The detecting process identifies a third transaction having identification information corresponding to the third event information based on the third event information regarding the third event and the second table; If the identification information registered in the third transaction and the identification information corresponding to the third event information registered in the first table match, the third transaction and the identification information registered in the third transaction The detection program according to appendix 1 or 2, characterized in that the detection program associates the identification information with the fourth transaction corresponding to the identification information.

(Supplementary note 4) The detecting process is based on the event information registered in the third transaction and the second table, and the detecting process is based on the event information registered in the third transaction and the second table. 5 transaction, and when identification information registered in the fifth transaction is identification information that identifies the third transaction, the third transaction and the fifth transaction are associated. The detection program described in 3.

(Supplementary note 5) The detection program according to supplementary note 4, wherein the detecting process associates the third transaction, the fourth transaction, and the fifth transaction in this order.

(Additional note 6) A detection method executed by a computer, comprising:
If a first event occurs, generate a first transaction corresponding to the first event and register it on the blockchain;
registering first event information regarding the first event and identification information of the first transaction in a first table;
registering second event information regarding a second event that occurred before the first event and identification information of the first transaction in a second table;
identifying identification information of a second transaction registered when a second event corresponding to the second event information occurs based on the second event information and the first table; and identifying the identified identification information. and the second event information in the first transaction,
When a trace request for a third event is received, a transaction related to the third event is detected based on the plurality of transactions registered in the blockchain, the first table, and the second table. A detection method characterized by performing processing.

(Additional Note 7) The detecting process includes identifying and specifying a transaction having identification information corresponding to the third event information based on the third event information regarding the third event and the first table. Supplementary Note 6, characterized in that when the event information registered in the transaction and the third event information match, the specified transaction is associated with the transaction corresponding to the identification information registered in the specified transaction. Detection method.

(Additional Note 8) The detecting process specifies a third transaction having identification information corresponding to the third event information based on the third event information regarding the third event and the second table; If the identification information registered in the third transaction and the identification information corresponding to the third event information registered in the first table match, the third transaction and the identification information registered in the third transaction 8. The detection method according to appendix 6 or 7, characterized in that the fourth transaction is associated with the identified identification information.

(Supplementary note 9) The detecting process is based on the event information registered in the third transaction and the second table, and the detecting process is performed based on the event information registered in the third transaction and the second table. 5 transaction, and when identification information registered in the fifth transaction is identification information that identifies the third transaction, the third transaction and the fifth transaction are associated. 8. Detection method according to 8.

(Supplementary note 10) The detection method according to supplementary note 9, wherein the detecting process associates the third transaction, the fourth transaction, and the fifth transaction in this order.

(Additional Note 11) When a first event occurs, a first transaction corresponding to the first event is generated and registered in the blockchain, and first event information regarding the first event and identification information of the first transaction are generated. and registering in a first table in association with, and registering in a second table in association with second event information regarding a second event that occurred before the first event and identification information of the first transaction; identifying identification information of a second transaction registered when a second event corresponding to the second event information occurs based on the second event information and the first table; and identifying the identified identification information. and a registration unit that registers the second event information in the first transaction;
When a trace request for a third event is received, a transaction related to the third event is detected based on the plurality of transactions registered in the blockchain, the first table, and the second table. A detection device comprising: a detection unit that performs

(Additional Note 12) The detection unit identifies a transaction having identification information corresponding to the third event information based on the third event information regarding the third event and the first table, and the identified transaction Supplementary note 11, characterized in that when the event information registered in the third event information matches the third event information, the specified transaction is associated with the transaction corresponding to the identification information registered in the specified transaction. Detection device.

(Additional Note 13) The detection unit specifies a third transaction having identification information corresponding to the third event information based on third event information regarding the third event and the second table, and If the identification information registered in the third transaction and the identification information corresponding to the third event information registered in the first table match, the third transaction and the identification information registered in the third transaction The detection device according to appendix 11 or 12, characterized in that the detection device associates the identification information with the corresponding fourth transaction.

(Additional Note 14) The detection unit is configured to detect, based on the event information registered in the third transaction and the second table, a fifth one having identification information corresponding to the event information registered in the third transaction. Supplementary note 13, characterized in that when identifying a transaction and identifying information registered in the fifth transaction is identification information identifying the third transaction, the third transaction and the fifth transaction are associated. The detection device described in .

(Additional Note 15) The detection device according to Additional Note 14, wherein the detecting process performs association in the order of the third transaction, the fourth transaction, and the fifth transaction.

20a, 20b, 20c, 20d terminal device 50 network 100a, 100b, 100c, 100d detection device 110 communication section 140 storage section 140a blockchain 140b world state 141 reference destination information 142 reference source information 150 control section 150a registration section 150b detection section 150c Synchronization part

Claims (6)

to the computer,
In response to the occurrence of a first event, generate a first transaction corresponding to the first event and register it on the blockchain;
registering first event information regarding the first event and identification information of the first transaction in a first table;
In response to the occurrence of a second event after the occurrence of the first event, a second transaction corresponding to the second event is generated and registered in the blockchain;
registering the first event and identification information of the second transaction in a second table in association with each other;
registering third event information regarding a third event that occurred before the first event and identification information of the first transaction in the second table;
Identifying identification information of a third transaction registered when a second event corresponding to the third event information occurs based on the third event information and the first table, and identifying the identified identification information. and the third event information in the first transaction,
When a trace request for the first event is received, identifying identification information of the first transaction from the first table and identifying information of the second transaction from the second table;
When a trace request for the fourth event is received, a transaction related to the fourth event is detected based on the plurality of transactions registered in the blockchain, the first table, and the second table. death,
Based on the fourth event information related to the fourth event and the first table, a transaction having identification information corresponding to the fourth event information is specified, and the event information registered in the specified transaction and the If the fourth event information matches, associating the identified transaction with the transaction corresponding to the identification information registered in the identified transaction;
A detection program characterized by causing processing to be executed. The detecting process includes identifying a fourth transaction having identification information corresponding to the fourth event information based on the fourth event information regarding the fourth event and the second table; When the identification information registered in the fourth transaction and the identification information corresponding to the fourth event information registered in the first table match, the fourth transaction and the identification information registered in the fourth transaction 2. The detection program according to claim 1, wherein the detection program is associated with a corresponding fifth transaction. The detecting process includes identifying a sixth transaction having identification information corresponding to the event information registered in the fourth transaction based on the event information registered in the fourth transaction and the second table. 3. The fourth transaction and the sixth transaction are associated with each other when the identification information registered in the sixth transaction is identification information that identifies the fourth transaction. detection program. 4. The detection program according to claim 3 , wherein the detecting process associates the fourth transaction, the fifth transaction, and the sixth transaction in this order. A detection method performed by a computer, comprising:
In response to the occurrence of a first event, generate a first transaction corresponding to the first event and register it on the blockchain;
registering first event information regarding the first event and identification information of the first transaction in a first table;
In response to the occurrence of a second event after the occurrence of the first event, a second transaction corresponding to the second event is generated and registered in the blockchain;
registering the first event and identification information of the second transaction in a second table in association with each other;
registering third event information regarding a third event that occurred before the first event and identification information of the first transaction in the second table;
Identifying identification information of a third transaction registered when a second event corresponding to the third event information occurs based on the third event information and the first table, and identifying the identified identification information. and the third event information in the first transaction,
When a trace request for the first event is received, identifying identification information of the first transaction from the first table and identifying information of the second transaction from the second table;
When a trace request for the fourth event is received, a transaction related to the fourth event is detected based on the plurality of transactions registered in the blockchain, the first table, and the second table. Then, based on the fourth event information related to the fourth event and the first table, a transaction having identification information corresponding to the fourth event information is identified, and event information registered in the identified transaction is identified. , when the fourth event information matches, associating the identified transaction with the transaction corresponding to the identification information registered in the identified transaction;
A detection method characterized by performing processing. In response to the occurrence of a first event, a first transaction corresponding to the first event is generated and registered in the blockchain, and first event information regarding the first event and identification information of the first transaction are are registered in a first table in association with each other, and in response to the occurrence of a second event after the occurrence of the first event, a second transaction corresponding to the second event is generated and registered in the blockchain; A first event and identification information of the second transaction are registered in a second table in association with each other, and third event information regarding a third event that occurred before the first event and identification information of the first transaction are registered in a second table. are registered in the second table in association with each other, and based on the third event information and the first table, the second event registered when the second event corresponding to the third event information occurs is registered. a registration unit that specifies identification information of the third transaction and registers the specified identification information and the third event information in the first transaction ;
When a trace request for the first event is received, identification information of the first transaction is specified from the first table, identification information of the second transaction is specified from the second table , and tracing of the fourth event is performed. When the request is received, a transaction related to the fourth event is detected based on the plurality of transactions registered in the blockchain, the first table, and the second table, and the transaction related to the fourth event is detected. Based on the fourth event information related to the event and the first table, a transaction having identification information corresponding to the fourth event information is specified, and the event information registered in the specified transaction and the fourth event a detection unit that associates the specified transaction with a transaction corresponding to identification information registered in the specified transaction when the information matches;
A detection device comprising:

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