A system for providing personal information using a one-time private key based on a blockchain of proof of use, the system comprising:
- a user terminal storing a public key and a private key, and transmitting one-time private key issue request information including user-authentication information and terminal identification information when a request for required personal information field information is made in response to a service use request;
- a blockchain network including multiple service-providing node servers that are configured to
- store a personal information transaction statement encrypted with the public key of any user terminal in a distributed manner,
- when a first one-time private key and a second one-time private key for any personal information transaction statement are received and the first one-time private key and the second one-time private key are in a pair, extract the personal information for a required personal information field that is requested, by decrypting the personal information transaction statement with the second one-time private key, and
- generate and issue a personal information submission including the extracted personal information for the required personal information field;
- a service provider server configured to
- make the request for the required personal information field information to the user terminal in response to the service use request,
- receive the first one-time private key,
- transmit personal information provision request information including the first one-time private key to the service-providing node server of a service-providing node server access address that is received when the first one-time private key is issued, and
- receive, in response thereto, the personal information submission from the service-providing node server in the blockchain network to acquire the personal information;
- and
- a blockchain alternative authentication server configured to
- store the user-authentication information and the terminal identification information for the user terminal, and a node transmission log including information on the service-providing node server storing the personal information transaction statement for a user of the user terminal,
- generate the first one-time private key and the second one-time private key in a pair when the one-time private key issue request information is received from the user terminal,
- transmit the first one-time private key to the service provider server from which the user terminal is to receive a service, and
- provide the second one-time private key to the service-providing node server in the blockchain network having the personal information transaction statement for the user of the user terminal, on the basis of the node transmission log.