Abstract: A malware detection method for a home network system including one or more home appliances that are connected to a home network includes: obtaining a plurality of setting values including at least information indicating a device type and an operating state of a target device subject to malware detection; selecting one detection model out of a plurality of detection models according to the plurality of setting values obtained; obtaining power consumption or current consumption of the target device; and detecting whether the target device is infected with malware, based on stable power or stable current obtained in the obtaining of the power consumption or the current consumption using the one detection model selected in the selecting, when the power consumption indicates stable power that varies within a predetermined range or the current consumption indicates stable current that varies within a predetermined range.

Abstract: A malware detection method for a home network system including one or more home appliances that are connected to a home network includes: obtaining a plurality of setting values including at least information indicating a device type and an operating state of a target device subject to malware detection; selecting one detection model out of a plurality of detection models according to the plurality of setting values obtained; obtaining power consumption or current consumption of the target device; and detecting whether the target device is infected with malware, using the one detection model selected in the selecting and based on the power consumption or the current consumption obtained.

Abstract: A method includes: acquiring transaction data that includes value information regarding a value to be transferred from a second user to a first user; executing a first smart contract recorded in a first blockchain by recording the transaction data in the first blockchain; and executing a second smart contract recorded in a second blockchain different from the first blockchain based on the first smart contract. The second smart contract is a smart contract for transferring at least a portion of the value to be transferred from the second user to the first user, from a first account held by the first user to a third account held by a third user.

Abstract: A control method in which each of an Internet of things (IoT) device and a user who uses the IoT device has a digital account includes: obtaining first transaction data for allowing the user who used the IoT device to transfer a first amount corresponding to a usage amount of the IoT device; specifying, from the first transaction data obtained, the digital account of the IoT device that is associated with an identifier uniquely assigned to hardware of the IoT device; and transferring the usage amount of the IoT device to the digital account of the IoT device by deducting the first amount from the digital account of the user and adding the first amount to the digital account of the IoT device based on the first transaction data obtained.

Abstract: An authentication server acquires and stores first transaction data in a distributed ledger, the first transaction data indicating a transfer of a first amount as a remaining transfer amount from a first account of a first user to a second account of a second user, and executes a first program. When the first amount is greater than a second amount indicating a balance in the first account, the first program transfers the second amount to the second account. The authentication server acquires and stores second transaction data in the distributed ledger, the second transaction data indicating a transfer of a fourth amount from a third account of a third user to the first account, and executes a second program. The second program transfers the fourth amount from the third account to the first account, and the first program transfers all or part of the fourth amount to the second account.

Abstract: A control method that is performed by a device in a distributed ledger system including a plurality of nodes each holding a distributed ledger includes: obtaining transaction data to be stored into the distributed ledger; obtaining a security level of each of the plurality of nodes; and preferentially determining a node having a higher security level among the plurality of nodes as a destination node for the transaction data.

Abstract: An electric lock control method includes: performing a first determination of whether a person is present in a predetermined region surrounding an electric lock, based on first information generated by an electronic device; when it is determined that a first person is present in the predetermined region in the performing of the first determination, performing a second determination of whether the first person is a person who is permitted to unlock the electric lock, based on second information related to movement of the first person; and controlling a state of the electric lock based on a result of the second determination, the state being a locked state or an unlocked state.

Abstract: A control method that is performed by a first device included in a plurality of devices includes: receiving, from a terminal being used by a second user, first transaction data indicating that value information is to be transferred from a first user to the second user; and storing the received first transaction data into a distributed ledger.

Abstract: A method includes: transmitting, to a second device used by a second user, identification information of a smart contract including a process of providing content according to a provision condition under which a first user allows to provide the content, through short-range wireless communication; receiving transaction data including identification information of the second device and instruction information for instructing to execute the smart contract, through short-range wireless communication; and storing the transaction data received in a distributed ledger and executing the smart contract, to change an owner of the content from the first user to the second user.

Abstract: A control method to be executed by a first device includes: receiving identification information identifying a second device from the second device by near-field communication; determining an evaluation value indicating appropriateness of the processing executed by the second device, with reference to a storage device that stores history information indicating processing executed by the second device; and restricting the near-field communication with the second device, based on the evaluation value determined.

Abstract: A control method according to the present disclosure is a method for controlling a first terminal carried by a first user and capable of communicating with a server via a network and includes: establishing short-range wireless communication by the first terminal with a second terminal carried by a second user; requesting the second terminal by the first terminal via the short-range wireless communication to provide item information, which is information related to at least one item included in one or more items worn by the second user, or requesting the server by the first terminal via the network to provide the item information, using identification information of at least one item that has been obtained upon the establishment of the short-range wireless communication; obtaining the item information by the first terminal; and transmitting, to the server, item positive-obtainment information indicating that the item information has been obtained.

Abstract: A control method according to the present disclosure is a method for controlling an information spot placed on at least one of a traffic light and roadside equipment and includes: obtaining, from a first mobile body via short-range wireless communication, first information obtained from a first path along which the first mobile body has traveled to reach the location of the information spot and indicating a situation on the first path; obtaining information related to the destination of a second mobile body, which is different from the first mobile body, from the second mobile body via the short-range wireless communication; and transmitting the first information to the second mobile body when it is determined that the second mobile body is to travel along at least a part of the first path to reach the destination.

Abstract: A control method for a first moving body includes: acquiring, from a second moving body, emergency information that includes information on a scheduled route on which an emergency vehicle travels in an emergency; and transmitting, by device-to-device communication, the emergency information to a third moving body that is predicted to travel on the scheduled route.

Abstract: A control method is executed by a first node holding a first distributed ledger in which a first blockchain is managed, and includes: obtaining, from a second node, a second blockchain managed by a second distributed ledger held by the second node, and comparing the second blockchain with the first blockchain; updating the first blockchain by adding the greater of at least one first different block contained in the first blockchain but not the second blockchain and at least one second different block contained in the second blockchain but not the first blockchain, after at least one common block, and adding at least one additional block containing at least one instance of transaction data contained in the lesser; and determining whether at least two instances of transaction data each containing at least two instances of contract information that conflict with each other are contained in the updated first blockchain.

Abstract: A control method is a control method for controlling a first node that manages a first blockchain in a first distributed ledger in a system utilized to use a service object and including the first node and a plurality of second nodes that each manage a second blockchain in a second distributed ledger. The control method includes: generating first transaction data indicating that the service object has been unlocked when the service object is to be used, the first transaction data including a first contract ID uniquely identifying a first contract to use the service object; and storing a block containing the first transaction data in the first blockchain.

Abstract: A control method according to the present disclosure is a control method for controlling a first node that holds a first distributed ledger in a system utilized to use a service object and including the first node and a plurality of second nodes that each hold a second distributed ledger. The control method includes: executing transmission processing for transmitting first transaction data to each of the plurality of second nodes; counting a total number of the second nodes that successfully communicate with the first node in the transmission processing; and storing the first transaction data in the first distributed ledger when the total number counted is greater than a predetermined number, and skipping storing the first distributed ledger in the first transaction data when the total number counted is not greater than the predetermined number.

Abstract: A control method according to the present disclosure is control method for controlling a first node that manages a first blockchain in a first distributed ledger in a system utilized to use a service object and including the first node and a plurality of second nodes that each manage a second blockchain in a second distributed ledger. The control method includes: obtaining first transaction data; determining whether a total number of second nodes, among the plurality of second nodes, that are capable of communication exceeds a predetermined value; and generating a first block containing the first transaction data only when the total number of second nodes that are capable of communication exceeds the predetermined value.

Abstract: A control method of an analysis device includes analyzing a binary code of each of a plurality of smart contracts stored in a first distributed ledger; obtaining, by using a result of the analyzing, items of commonization information expressing, in a common format, items of information provided by the plurality of smart contracts; and generating transaction data that includes the items of commonization information obtained and performing control of storing the transaction data generated into a second distributed ledger.

Abstract: A control method is to be executed by one of a plurality of servers included in an information management system. Each of the plurality of servers owns a distributed ledger. The control method includes: receiving transaction data including a signature generated using any of a plurality of signing keys owned by a user, each of the plurality of signing keys being associated with a reliability; determining whether the reliability associated with the signature included in the transaction data received is higher than or equal to a specified value; storing the transaction data in the distributed ledger, if reliability is determined to be higher than or equal to the specified value in the determining; and executing invalidation processing to invalidate the transaction data, if the reliability is determined to be lower than the specified value in the determining.

Abstract: An unauthorized communication detection method detects an unauthorized communication message on an in-facility network over which at least two devices including a first device and a second device are communicably connected, and includes: receiving, from the first device, a communication message transmitted from the first device to the second device; obtaining, when the communication message is received from the first device, first information indicating a state of at least one of (a) a person in a facility and (b) the at least two devices, and determining whether to execute processing pertaining to a device control command that controls the second device when the communication message received from the first device is a communication message including the device control command, the determining being performed based on the first information; and executing the processing pertaining to the device control command when the determining determines to execute the processing.