Abstract: A method for authentication based on a blockchain network is provided. The method includes steps of: an authentication-supporting server (a) if verification is requested by a certificate authority (CA) app, verifying a signature value and transmitting an access token to a user device, supporting the CA-affiliate app to transmit a login request to a CA-affiliate server, and registering the access token in the blockchain network, and transmitting a verification request to the blockchain network to transmit the access token to the authentication-supporting server, and register the access token in the blockchain network, and transmitting the access token to the user device, and transmit the login request to the CA-affiliate server, and (b) performing one of (i) verifying the access token, and (ii) transmitting the verification request to the blockchain network, and transmitting a verification-result to the CA-affiliate server, to allow the CA-affiliate app to log in to the CA-affiliate server.

Abstract: A method, user device, and service providing server are provided for information management using a specific tree based on a blockchain. Aspects of the described approach include registering in an open ledger of the blockchain private data that belongs to a set of private data that identifies a particular subject. Furthermore, pseudo-public data including prefix values that correspond to specific private data are generated, registered as sub-data corresponding to a sub-structure of a specific leaf node to which the specific private data is allocated. Also, a pseudo-public function is created based on the pseudo-public data allocated to the specific leaf node.

Abstract: The present invention, when at least one from among chat participants requests recording of data generated by the chat participants in an environment in which a messenger bot participates in a chat, registers at least a portion of the generated data as recorded data in a database, provides a transaction ID indicating location in the database of the data registered therein to at least one participant from among the chat participants, determines, in response to a recorded data-related verification request, whether input data included in the verification request corresponds to the recorded data, and, if the input data corresponds to the recorded data, then concludes the recorded data-related verification to have been successful.

Abstract: Once information requesting superseding of a log-in through an authentication app is obtained from a service provision app on a user terminal, a service provision server transfers authentication request response information to the service provision app and, after an authentication redirection request thereof is transferred to the authentication app and then server challenge request information is obtained, server challenge request response information is transferred to the authentication app, thereby supporting the determination as to whether or not certificates of the server and the app are valid, an authentication result message including information on the validity is obtained from an authentication server, a predetermined access token is transferred to the service provision app, and thereby the log-in is handled by providing support such that a service can be used.

Abstract: According to the present invention, a method for delegating a login via PKI-based authentication for a login request of a user by using a smart contract and a blockchain database is provided.

Abstract: The present disclosure provides a method for superseding a log-in through PKI-based authentication with respect to a log-in request of a user by using a blockchain database.

Abstract: A method is provided for providing a notary service for a file, the method includes the steps in which: (a) when a notary service request for a specific file is obtained, a server generates, by using a hash function, or supports the generation of, a message digest of the specific file; and (b) if a predetermined condition is satisfied, the server registers, in a database, or supports the registration of, a representative hash value or a value obtained by processing the representative hash value, the representative hash value being generated by calculating at least one neighboring hash value that matches a specific hash value, wherein the specific hash value is a hash value of the result of encrypting the message digest with a private key of a first user, a private key of a second user and a private key of the server.

Abstract: Provided is a method according to the present invention comprising the steps of: (a) generating a message digest of a particular file when a request for authenticating same is obtained; (b) when a message digest encoded with a private key of a first user and a message digest encoded with a private key of a second user are obtained, and if the (i) (A) information for the message digest, which was encoded with the private key of the first user, decoded with a public key of the first user, (ii) (B) information for the message digest, which was encoded with the private key of the second user, decoded with a public key of the second user, and (C) the message digest generated in step (a) match, then registering, in a database, a hash value of the message digest encoded using the private key of the first user, private key of the second user and a private key of a server; and (c) obtaining a transaction ID reflecting location information of the registered hash value in the database.

Abstract: The present disclosure relates to a method for providing a payment agency service and a server using same, and a method for registering an authentication certificate, a method for providing a payment agency service, a card company server, and a payment agency server. The method comprises steps of a payment agency server: (a) delivering identity authentication information and a first push token ID delivered from a user terminal to a card company server; (b) delivering a successful authentication result to the user terminal to support generating and saving a public key and a private key of the user; and (c) managing the first push token ID or a second push token ID as an integrated push token ID when the first push token ID and the second push token ID match, and saving registration information including the integrated push token ID and the public key.

Abstract: Provided is a method according to one embodiment of the present invention comprising the steps of: (a) a server generating, by means of a hash function, a message digest (MD) of a particular file when a request for authenticating same is obtained; (b) when an MD encoded with a private key of a particular user is obtained, and if (A) information for the MD, which was encoded with the private key of the particular user, decoded with a public key of the particular user matches (B) the MD generated in step (a), then the server registering, in a database, a hash value of the MD encoded with the private key of the particular user and a private key of the server; and (c) the server obtaining a transaction ID.

Abstract: Provided is a method according to one embodiment of the present invention comprising the steps of: (a) a server generating, by means of a hash function, a message digest (MD) of a particular file when a request for authenticating same is obtained; (b) when an MD encoded with a private key of a particular user is obtained, and if (A) information for the MD, which was encoded with the private key of the particular user, decoded with a public key of the particular user matches (B) the MD generated in step (a), then the server registering, in a database, a hash value of the MD encoded with the private key of the particular user and a private key of the server; and (c) the server obtaining a transaction ID.

Abstract: A method for a Single Sign On (SSO) service using a Public Key Infrastructure (PKI) based on blockchain networks, and device and server using the same are provided. The method has objects and effects of providing (a) the SSO based on blockchain network technology to efficiently protect authentication information on users from external attacks, (b) the SSO assuring information security and preventing forgery by applying a hash function and encryption to user certificates, and (c) the SSO preventing problems incurred by information theft beforehand through a user-authentication using disposable verification values.

Abstract: A method for a Single Sign On (SSO) service using a Public Key Infrastructure (PKI) based on blockchain networks, and device and server using the same are provided. The method has objects and effects of providing (a) the SSO based on blockchain network technology to efficiently protect authentication information on users from external attacks, (b) the SSO assuring information security and preventing forgery by applying a hash function and encryption to user certificates, and (c) the SSO preventing problems incurred by information theft beforehand through a user-authentication using disposable verification values.

Abstract: A method for authentication based on a blockchain network is provided. The method includes steps of: an authentication-supporting server (a) if verification is requested by a certificate authority (CA) app, verifying a signature value and transmitting an access token to a user device, supporting the CA-affiliate app to transmit a login request to a CA-affiliate server, and registering the access token in the blockchain network, and transmitting a verification request to the blockchain network to transmit the access token to the authentication-supporting server, and register the access token in the blockchain network, and transmitting the access token to the user device, and transmit the login request to the CA-affiliate server, and (b) performing one of (i) verifying the access token, and (ii) transmitting the verification request to the blockchain network, and transmitting a verification-result to the CA-affiliate server, to allow the CA-affiliate app to log in to the CA-affiliate server.

Abstract: A method for secure transmission of user-authenticating information is provided. The method includes steps of: a service-providing server (a) determining whether a public key of the user is registered in a blockchain network, and instructing a user-authenticating information generator to generate user-authenticating information for reference, instructing an encrypting engine to encrypt the generated user-authenticating information for reference by using the public key of the user retrieved from the blockchain network, and instructing a message-sending part to transmit the encrypted user-authenticating information for reference to a mobile device of the user; and (b) in case that user-authenticating information for comparison is acquired from the user device and if the user-authenticating information for comparison is determined as identical to the user-authenticating information for reference, providing the user device with the service desired by the user.

Abstract: Provided is a method according to one embodiment of the present invention comprising the steps of: (a) a server generating, by means of a hash function, a message digest (MD) of a particular file when a request for authenticating same is obtained; (b) when an MD encoded with a private key of a particular user is obtained, and if (A) information for the MD, which was encoded with the private key of the particular user, decoded with a public key of the particular user matches (B) the MD generated in step (a), then the server registering, in a database, a hash value of the MD encoded with the private key of the particular user and a private key of the server; and (c) the server obtaining a transaction ID.

Abstract: A method for information management using a specific tree based on a blockchain is provided. The method includes steps of: a user device (a) if private data related to a subject are acquired from a specific user of the user device, generating the specific tree, wherein the specific tree has leaf nodes to which private function values, created by applying its algorithm to the private data or their processed values, is allocated; and (b) (i) performing one of (i-1) registering a representative value of the specific tree as a subject ID of the subject and (i-2) registering information on the specific tree as the subject ID of the subject, in the blockchain, and (ii) supports another device to register one of (ii-1) the representative value of the specific tree as the subject ID and (ii-2) the information on the specific tree as the subject ID, in the blockchain.

Abstract: A method for providing a notary service for a file is provided. The method includes steps in which: (a) when a notary service request for a specific file is obtained, a server generates, by using a hash function, or supports the generation of, a message digest of the specific file; and (b) if a predetermined condition is satisfied, the server registers, in a database, or supports the registration of, a representative hash value or a value obtained by processing the representative hash value, the representative hash value being generated by calculating at least one neighboring hash value that matches a specific hash value, wherein the specific hash value is a hash value of the result of encrypting the message digest with a private key of a specific user and a private key of the server.

Abstract: The present invention provides a method for issuing an electronic voucher, the method comprising: (a) a step in which a server checks whether or not (i) electronic voucher data, (ii) a public key of a specific issuer and (iii) a signature value of the specific issuer are valid; and (b) a step in which, if the validity check result is positive, the server registers or supports the registration of a function value associated with (i) the electronic voucher data, (ii) the public key of the specific issuer and (iii) the signature value of the specific issuer in a public blockchain network, and acquires or supports the acquisition of Txid indicating information on the location of the function value, registered in the public blockchain network, within the public blockchain network.

Abstract: The present invention relates to a method for issuing a currency comprising the steps of: (a) confirming the validity of a currency issuing transaction and a currency issuer, when the currency issuing transaction for issuing the currency from the currency issuer is obtained, the currency issuing transaction including (i) currency receiver information, (ii) issued amount of the currency, (iii) a public key of the currency issuer, and (iv) a signature value of the currency issuer signing the (i), (ii), and (iii) with a private key of the currency issuer; and (b) registering the currency issuing transaction or a function value thereof on a public blockchain network, and obtaining a currency issuance public transaction ID indicating location information of the currency issuing transaction or the function value thereof on the public blockchain network, when the currency issuing transaction and the currency issuer are deemed valid.