Abstract: The present disclosure relates to a system and a method for providing personal information for an online service system. More particularly, the present disclosure relates to a system and a method for providing personal information using a one-time private key based on a blockchain of proof of use, wherein personal information is registered and stored in a distributed manner in a blockchain network, services in online and offline service systems are used by using alternative authentication identification information that is anonymous and includes a public key to access the personal information in the blockchain network, and for membership registration and login, only the alternative authentication identification information is used to receive a service, become a member of a service, and to log in, without providing the personal information.

Abstract: The present disclosure relates to a system and a method for providing personal information for an online service system. More particularly, the present disclosure relates to a system and a method for providing personal information using a one-time private key based on a blockchain of proof of use, wherein personal information is registered and stored in a distributed manner in a blockchain network, services in online and offline service systems are used by using alternative authentication identification information that is anonymous and includes a public key to access the personal information in the blockchain network, and for membership registration and login, only the alternative authentication identification information is used to receive a service, become a member of a service, and to log in, without providing the personal information.

Abstract: An escrow non-face-to-face cryptocurrency transaction device and method using a phone number is proposed. The device and method includes: providing a phone number wallet that uses a phone number of a user as a login ID; using the phone number wallet having an electronic wallet address of a phone number system so as to remit and deposit cryptocurrency stored in the phone number wallet in an escrow virtual wallet of an escrow virtual wallet address generated for a one-time use in a one-time escrow virtual wallet; transmitting, to a remitter, escrow authentication information that enables a secure connection to the escrow virtual wallet and enables withdrawal authentication; and remitting the cryptocurrency deposited in the escrow virtual wallet address to an electronic wallet address of a recipient who inputs the escrow authentication information directly received from the remitter, so as to withdraw the cryptocurrency.

Abstract: Provided are a user authentication system and method using a physical financial card. A user of the physical financial card is authenticated based on information acquired from the physical financial card using a contact or non-contact scheme. When a user requesting authentication for the first time is successfully authenticated, a unique identifier (UID) of the physical financial card and a personal identification number (PIN) for the authentication are registered. The user is authenticated using the registered UID and PIN information in the next authentication, so that security and convenience are improved.

Abstract: A credit card paying method comprises the steps of: firstly designating a mobile communications terminal capable of reading the information of a credit card from the magnetic and IC chip thereof for a virtual credit card paying terminal; and directly contacting a credit card with the mobile communications terminal designated as the virtual credit card paying terminal in order to pay a bill for an online or offline purchase made by the user of the mobile communications terminal, thereby preventing the credit card information of the user from being undesirably exposed to a third party because the payment for a purchase can be made by directly contacting the credit card with the mobile communications terminal.