Abstract: A control device comprising, a control section configured to control an authentication process of performing a process related to device authentication together with at least one communication device on a basis of information included in a signal received through wireless communication with the communication device, wherein the control section performs control in such a manner that a signal including authentication information that is information to be used for the authentication process is transmitted to the communication device through the wireless communication, the authentication information varying depending on signal types, which are types of roles of signals to be transmitted to the communication device in the authentication process.

Abstract: Pieces of information on multiple file management systems are managed by one contract in a distributed ledger. An administrator terminal includes: a file management system generation unit that issues a contract generation transaction for generating, in blockchain data, a contract in which a network identifier that identifies a file management system is associated with an identifier of a participant terminal in a blockchain system, and notifying the participant terminal of the network identifier and an identifier of the contract; and a file management control unit that issues a registration transaction for registering, in the contract, connection information of the administrator terminal in the file management system, acquires connection information of the participant terminal in the file management system from the contract, and establishes a P2P connection with the participant terminal based on the acquired connection information.

Abstract: A data circulation support apparatus includes a memory and a processor configured to execute calculating a score indicating reliability of a contract condition related to circulation of data based on information indicating a sense of value related to contract compliance of each of a user of a circulation source of the data and a user of a circulation destination of the data, and to identifying a contract condition whose score is greater than or equal to a threshold; and recording the contract condition in a ledger upon receiving information indicating approval to the contract condition by the user of the circulation source or the circulation destination.

Abstract: Pieces of information on multiple file management systems are managed by one contract in a distributed ledger. An administrator terminal includes: a file management system generation unit that issues a contract generation transaction for generating, in blockchain data, a contract in which a network identifier that identifies a file management system is associated with an identifier of a participant terminal in a blockchain system, and notifying the participant terminal of the network identifier and an identifier of the contract; and a file management control unit that issues a registration transaction for registering, in the contract, connection information of the administrator terminal in the file management system, acquires connection information of the participant terminal in the file management system from the contract, and establishes a P2P connection with the participant terminal based on the acquired connection information.

Abstract: A settlement system includes a service provider device 2 which transmits a template information transaction including a template of a transaction to a network 4 of a first blockchain, a user device which transmits, to the network 4 of the first blockchain, a payment information transaction that includes an electronic signature generated by using the template of the transaction and a payment amount, and a smart contract 41, wherein the smart contract 41 verifies the electronic signature by using the payment amount and the template of the transaction, the service provider device 2 generates a settlement transaction by using the template of the transaction, the electronic signature and the payment amount, and transmits the settlement transaction to a network 3 of a second blockchain, a plurality of output conditions are set to the template of the transaction, and the settlement transaction becomes usable when any one of the plurality of output conditions is satisfied.

Abstract: The present invention prevents falsification of ABI information and makes it possible for the users to safely read data on a blockchain. A registration terminal 1 includes an extraction unit 142 that extracts from a smart contract, ABI information used to access the smart contract and a transaction issuing unit 13 that issues a transaction including bytecode generated by compiling the smart contract and the ABI information, and an approval terminal 2 includes a verification unit 152 that verifies whether it is possible to access the bytecode included in the transaction by using the ABI information included in the transaction and a block generation unit 154 that, if it is possible to access the bytecode, generates a block including the transaction and makes the block and the ABI information reflected on a distributed ledger 11 of each terminal in the blockchain system.

Abstract: Pieces of information on multiple file management systems are managed by one contract in a distributed ledger. An administrator terminal includes: a file management system generation unit that issues a contract generation transaction for generating, in blockchain data, a contract in which a network identifier that identifies a file management system is associated with an identifier of a participant terminal in a blockchain system, and notifying the participant terminal of the network identifier and an identifier of the contract; and a file management control unit that issues a registration transaction for registering, in the contract, connection information of the administrator terminal in the file management system, acquires connection information of the participant terminal in the file management system from the contract, and establishes a P2P connection with the participant terminal based on the acquired connection information.

Abstract: A determination apparatus according to an embodiment includes: an input unit that inputs information indicating a first transaction action expected to be performed by a first user, information indicating a second transaction action expected to be performed by a second user, information regarding the first user, and information regarding the second user disclosed by the second user to the first user; an expected value calculation unit that calculates an expected value indicating reliability with which the second user performs the second transaction action when the first user performs the first transaction action by use of the information indicating the first transaction action, the information indicating the second transaction action, the information regarding the first user, and the information regarding the second user; and a feasibility determination unit that determines feasibility of a transaction contract represented by the first transaction action and the second transaction action by use of the expected

Abstract: A registration terminal according to an embodiment is a registration terminal which is connectable to a distributed ledger network, and includes: a token generation unit configured to generate a transaction related to generation of a token to the distributed ledger network and transmit the transaction to the distributed ledger network to generate the token in the distributed ledger network; and a registration unit configured to generate information in which access information to the token is set in a file to be processed, generate an identifier for the file to be processed, generate a transaction related to registration of the identifier to the token, and transmit the transaction to the distributed ledger network to register the identifier in the token.

Abstract: A registration terminal according to an embodiment is a registration terminal connectable to a distributed ledger network, and includes a first generation unit that generates a private key for an identifier used for generation of an identifier of a file and a public key for an identifier used for generation of the identifier, a second generation unit that generates a transaction related to generation of management information to the distributed ledger network and transmits the transaction to the distributed ledger network to generate the management information to the distributed ledger network, and a third generation unit that generates an identifier of a processing target file as an identifier registered in the management information by using the public key for an identifier.

Abstract: A calculation apparatus according to an embodiment includes: an input unit that inputs information indicating a first action expected to be performed by a first user, information indicating a second action expected to be performed by a second user, information regarding the first user, information regarding the second user, and information indicating a relationship between the first user and the second user; and an expected value calculation unit that calculates an expected value indicating reliability with which the second user performs the second action when the first user performs the first action by using the information indicating the first action, the information indicating the second action, the information regarding the first user, the information regarding the second user, and the information indicating the relationship.

Abstract: An identifier change management apparatus according to an embodiment includes: a distributed ledger in which an identifier change program holding a public key and a first hash value; an identifier change key input unit that receives a secret key; a hash chain management unit that holds a seed value of a hash value used in the identifier change; a transaction issuing unit that issues an identifier change transaction including a signature value of an electronic signature that has been performed using the secret key and a second hash value generated using the seed value; and a program control management unit that changes the identifier, by the identifier change program, on condition that the signature value included in the identifier change transaction is verifiable by using the public key and a value obtained by applying a hash function to the second hash value becomes the first hash value.

Abstract: An identifier change management apparatus according to one embodiment includes: a key management unit configured to manage a group of private keys including a first private key; a message input unit configured to receive a message; a transaction issuing unit configured to issue an identifier change transaction including a hash value of the message and a first signature value generated from the first private key; a distributed ledger in which an identifier change program is registered, the identifier change program holding a pairing public key used when the identifier is changed and a second signature value; and a program control management unit configured to calculate a pairing signature value by the first and second signature values by the identifier change program and change the identifier on condition that the pairing signature value, the pairing public key, and the hash value satisfy an equation using a predetermined pairing function.

Abstract: An identifier change management apparatus according to an embodiment includes: a distributed ledger in which an identifier change program holding a public key used in an identifier change is registered; a distributed ledger management unit that manages the distributed ledger; an identifier change key input unit that receives a secret key used in the identifier change; a transaction issuing unit that issues an identifier change transaction including a signature value of an electronic signature that has been performed using the secret key; and a program control management unit that changes the identifier when the distributed ledger management unit receives the identifier change transaction, by the identifier change program, on condition that the signature value included in the identifier change transaction is verifiable by using the public key.

Abstract: A registration terminal according to the present embodiment is connectable to a first distributed ledger network and a second distributed ledger network. The registration terminal includes a registration unit, a first control unit, and a second control unit. The registration unit registers a file in an external storage service. The first control unit generates a registration transaction including a file identifier assigned to the file by the storage service and a verification key, and transmits the registration transaction to the first distributed ledger network. The second control unit generates a token transaction related to generation of a token and including a signature object message including the file identifier and a signature value obtained by digitally signing the signature object message with a signature key, and transmits the token transaction to the second distributed ledger network.

Abstract: An objective is to manage contract data registered in a distributed ledger with part of the contract data flexibly concealed without a centralized concealment server and without bothering the user with complicated procedures or the key management. A data registration method performed by a computer includes: generating a common key for encrypting and decrypting an item included in data that is registered in a distributed ledger; acquiring a public key for each account of a user having access authority to the item; encrypting the common key with the public key for each account; and registering the common key encrypted for each account in the distributed ledger via a transaction.

Abstract: A user terminal according to the present embodiment is a user terminal connectable to a first distributed ledger network and a second distributed ledger network, and includes a generation unit, a first control unit, and a second control unit. The generation unit generates a decentralized identifier related to a user using a verification key. The first control unit generates a registration transaction including the verification key and the decentralized identifier, and transmits the registration transaction to the first distributed ledger network. The second control unit generates a token transaction related to issuance of a token, the token transaction including data of the user and the decentralized identifier, and transmits the token transaction to the second distributed ledger network.

Abstract: Upon receiving a usage request that includes a file identifier and a version identifier from a user terminal 20, a control server 10 transmits a file request that is based on the usage request to a file management system, and transmits a permission information request that is based on the usage request to a distributed ledger system. Upon receiving the file request, the file management system acquires the file that corresponds to the combination of the file identifier and the version identifier and transmits the file to the control server 10. Upon receiving the permission information request, the distributed ledger system acquires permission information that corresponds to the combination of the file identifier and the version identifier from a distributed ledger, and transmits the permission information to the control server 10. The control server 10 transmits the file to the user terminal 20 if the user of the user terminal has viewing permission based on the permission information.

Abstract: A data sharing system includes a plurality of IoT networks 20, and a plurality of management terminals 1 connected to a blockchain network 10. In the data sharing system, each management terminal 1 includes a reception unit 12 that receives a transaction including IoT terminal information related to an IoT terminal 2 from at least one IoT network 20 of the plurality of the IoT networks 20, a communication unit 13 that transmits and receives the transaction to/from another management terminal 1, a block generation unit 14 that attempts to generate a block including the transaction, a block verification unit 15 that verifies a block generated by another management terminal 1, and a distributed ledger 16 that stores the generated blocks.

Abstract: A key exchange system method safely conceal secret information recorded on a blockchain. A first terminal includes a license issuing unit that generates a first transaction including a first public key, a first key storage region that retains a first secret key, and a first encrypting and decrypting unit that generates a common key using deal-specific information, a second public key, and the first secret key, and a second terminal includes a license requesting unit that generates a second transaction including the second public key, a second key storage region that retains a second secret key, and a second encrypting and decrypting unit that generates the common key using deal-specific information, the first public key, and the second secret key. The first encrypting and decrypting unit encrypts secret information using the common key. The second encrypting and decrypting unit decrypts the encrypted secret information using the common key.