Abstract: The present disclosure relates to a system and a method for a blockchain platform-based service, the method including generating, at a smart contract deployed on a blockchain platform, a pair of a first private key and a first public key, transmitting the first public key generated at the smart contract to a first computing device, receiving, at the smart contract, data encrypted with the first public key at the first computing device, decrypting, at the smart contract, the encrypted data with the first private key, and storing, at the smart contract, the data decrypted with the first private key as a local variable of the smart contract.

Abstract: The present disclosure relates to a system and a method for autonomously operating a public ledger-based credential, the method including registering credential issuance authority information in a public ledger of a blockchain platform, and verifying a credential issued to a first computing device by referring to the credential issuance authority information registered in the public ledger. The credential issuance authority information includes an attribute value range assigned to a credential issuer and public key information of the credential issuer. A second computing device verifies the credential issued to the first computing device by referring to the credential issuance authority information registered in the public ledger.

Abstract: The present disclosure relates to an IoT device control system and method, including: by a user terminal, capturing an image of a real space that includes therein one or more IoT devices; when capturing the image, matching and registering at least one of a position and a posture of the user terminal with an IoT device selected by a user; displaying a control screen for the selected IoT device when the user terminal satisfies a condition, wherein the condition is determined by using at least one of the position and the posture of the user terminal matched and registered with the selected IoT device; and controlling the selected IoT device according to a user input received through the control screen. According to the present disclosure, a user can conveniently check and control an IoT device to be controlled, by using virtual reality and augmented reality.

Abstract: The present disclosure relates to an IoT device control system and method, including: by a user terminal, capturing an image of a real space that includes therein one or more IoT devices; when capturing the image, matching and registering at least one of a position and a posture of the user terminal with an IoT device selected by a user; displaying a control screen for the selected IoT device when the user terminal satisfies a condition, wherein the condition is determined by using at least one of the position and the posture of the user terminal matched and registered with the selected IoT device; and controlling the selected IoT device according to a user input received through the control screen. According to the present disclosure, a user can conveniently check and control an IoT device to be controlled, by using virtual reality and augmented reality.

Abstract: A method for calculating distributed network nodes' contribution to a service according to the present disclosure comprises the steps of: receiving, by a server, details of contribution to a service from a plurality of nodes; verifying, by the server, the received details of contribution to a service; announcing, by the server, the verified details of contribution to a service; and using a block chain including a block that includes the announced details of contribution to a service issued by one of the plurality of nodes, calculating the one node's contribution to a service. According to the present disclosure, it is possible to calculate distributed network nodes' contribution to a service. It is also possible to separately calculate the degrees of contribution of distributed network nodes to a specific service. Further, it is possible to ensure the transparency of the details of calculation of distributed network nodes' contribution to a service.

Abstract: A method for calculating distributed network nodes' contribution to a service according to the present disclosure comprises the steps of: receiving, by a server, details of contribution to a service from a plurality of nodes; verifying, by the server, the received details of contribution to a service; announcing, by the server, the verified details of contribution to a service; and using a block chain including a block that includes the announced details of contribution to a service issued by one of the plurality of nodes, calculating the one node's contribution to a service. According to the present disclosure, it is possible to calculate distributed network nodes' contribution to a service. It is also possible to separately calculate the degrees of contribution of distributed network nodes to a specific service. Further, it is possible to ensure the transparency of the details of calculation of distributed network nodes' contribution to a service.