Abstract: Provided are a method of managing off-chain data and a device therefor. A method of operating a device that constitutes a blockchain network includes generating a first hash value regarding unit data using a first hash function and determining a target shard to store the unit data from among a plurality of shards based on the first hash value, transmitting a first request to store the unit data in the target shard to an external device, and obtaining a changed root value of the target shard changed as the unit data is stored from the external device, wherein the root value represents entire data stored in the target shard.

Abstract: An electronic device includes a memory including instructions; and a processor electrically connected to the memory and configured to execute the instructions, wherein, when the instructions are executed by the processor, the processor is configured to perform a plurality of operations: recording a driver registration result of a vehicle owner in profile data stored in a blockchain; and generating a combination identifier (CID) in which a vehicle and a driver are mapped by mapping vehicle information and driver information recorded in the profile data, wherein the CID is segmented into blockchain-based decentralized identifiers (DIDs) respectively corresponding to vehicle usage scenarios of the driver and includes at least one of vehicle information, driver information, vehicle owner information, or CID type information.

Abstract: A secure file-deletion function providing apparatus includes a request input unit configured to receive a file deletion request to delete a file stored in an apparatus from a user; a file deletion unit for deleting the file included in the file deletion request, and a secure file-deletion unit for overwriting a region including a region that stores the file with a dummy value in order to make it more difficult and/or impossible to recover the file deleted by the file deletion unit.

Abstract: A secure file-deletion function providing apparatus includes a request input unit configured to receive a file deletion request to delete a file stored in an apparatus from a user; a file deletion unit for deleting the file included in the file deletion request, and a secure file-deletion unit for overwriting a region including a region that stores the file with a dummy value in order to make it more difficult and/or impossible to recover the file deleted by the file deletion unit.

Abstract: A secure file-deletion function providing apparatus includes a request input unit configured to receive a file deletion request to delete a file stored in an apparatus from a user; a file deletion unit for deleting the file included in the file deletion request, and a secure file-deletion unit for overwriting a region including a region that stores the file with a dummy value in order to make it more difficult and/or impossible to recover the file deleted by the file deletion unit.

Abstract: A secure file-deletion function providing apparatus includes a request input unit configured to receive a file deletion request to delete a file stored in an apparatus from a user; a file deletion unit for deleting the file included in the file deletion request, and a secure file-deletion unit for overwriting a region including a region that stores the file with a dummy value in order to make it more difficult and/or impossible to recover the file deleted by the file deletion unit.