Authentication system, user terminal, authentication method, and program

A user terminal to be used by a user, the user terminal comprising

• a user terminal control part, wherein
• the user terminal control part is configured to execute a second request, to a first node belonging to a first decentralized network equipped with a plurality of nodes sharing a first decentralized ledger, and the first node is accessible to first information about the user,
• the user terminal control part is configured to execute a first request, to a second node belonging to a second decentralized network equipped with a plurality of nodes sharing a second decentralized ledger, and the second node is accessible to second information about the user,
• a first wallet of the first decentralized ledger stores a URI of the first information, and first specification information for specifying a second wallet of the second decentralized ledger, the first specification information is stored as a first non-fungible token serving as a token having non-fungibility,
• the second wallet of the second decentralized ledger stores a URI of the second information, and second specification information for specifying the first wallet, the second specification information is stored as a second non-fungible token serving as a token having non-fungibility,
• a second control part of the second node, when the first request is executed, then requests the first node to perform first authentication to authenticate the second node for the user based on the first non-fungible token, by specifying the first wallet using the second specification information, and
• a first control part of the first node, when the second request is executed, then requests the second node to perform second authentication to authenticate the first node for the user based on the second non-fungible token, by specifying the second wallet using the first specification information.

An authentication method comprising the steps of:

• storing a URI of first information about a user, into a first wallet of a first decentralized ledger shared by a plurality of nodes included in a first decentralized network;
• storing, into the first wallet, first specification information for specifying a second wallet of a second decentralized ledger shared by a plurality of nodes included in a second decentralized network, as a first non-fungible token;
• storing a URI of second information about the user into the second wallet;
• storing second specification information for specifying the first wallet into the second wallet, as a second non-fungible token;
• requesting a first node to authenticate a second node for the user based on the first non-fungible token, by specifying the first wallet using the second specification information, the first node belonging to the first decentralized network and being accessible to the first information, the second node belonging to the second decentralized network and being accessible to the second information;
• and
• requesting the second node to authenticate the first node for the user based on the second non-fungible token, by specifying the second wallet using the first specification information.

A non-transitory computer-readable storage medium that stores a program to be executed by a computer configured to control a user terminal used by a user, the program making the computer realize the functions of:

• executing a second request to a first node belonging to a first decentralized network and being accessible to first information about the user, the first decentralized network equipped with a plurality of nodes sharing a first decentralized ledger;
• and
• executing a first request to a second node belonging to a second decentralized network and being accessible to second information about the user, the second decentralized network equipped with a plurality of nodes sharing a second decentralized ledger, wherein
• a first wallet of the first decentralized ledger stores a URI of the first information, and first specification information for specifying a second wallet of the second decentralized ledger, the first specification information is stored as a first non-fungible token serving as a token having non-fungibility,
• the second wallet of the second decentralized ledger stores a URI of the second information, and second specification information for specifying the first wallet, the second specification information is stored as a second non-fungible token serving as a token having non-fungibility,
• when the first request is executed, a second control part of the second node then requests the first node to perform first authentication to authenticate the second node for the user based on the first non-fungible token, by specifying the first wallet using the second specification information, and
• when the second request is executed, a first control part of the first node then requests the second node to perform second authentication to authenticate the first node for the user based on the second non-fungible token, by specifying the second wallet using the first specification information.