Registration terminal, holder terminal, method, and program

A registration terminal connectable to a distributed ledger network in which a token including an identifier of a processing target file is held, the registration terminal comprising:

• one or more processors;
• and
• a storage medium having computer program instructions stored therein that, when executed by the one or more processors, perform to:
• generate a random number used for generation of an identifier of a processing target file after update on the basis of a private key for an identifier used for generation of the identifier, the processing target file before update, a random number used for generation of an identifier of the processing target file before update, and the processing target file after update;
• and
• generate information in which the random number is set in the processing target file after update.

A file holder terminal connectable to a distributed ledger network in which management information including an identifier of a processing target file is held,

• wherein information on access to the management information, an electronic signature, and a public key used for verification of the electronic signature are associated with the processing target file, and
• the file holder terminal comprising:
• one or more processors;
• and
• a storage medium having computer program instructions stored therein that, when executed by the one or more processors, perform to:
• verify the electronic signature described in the processing target file by using a public key described in the processing target file and used for verification of the electronic signature;
• acquire the file identifier from the management information by using the information on access to the management information described in the processing target file;
• generate an identifier of the processing target file by using the public key for an identifier described in the processing target file;
• and
• determine that the identifier acquired by the acquisition unit matches the identifier generated by the generation unit.

A method performed by a registration terminal connectable to a distributed ledger network, the registration method comprising:

• generating a private key for an identifier used for generation of an identifier of a file and a public key for an identifier used for generation of the identifier;
• generating a transaction related to generation of management information to the distributed ledger network and transmitting the transaction to the distributed ledger network to generate the management information to the distributed ledger network;
• and
• generating an identifier of a processing target file as an identifier registered in the management information by using the public key for an identifier.