Abstract: An encryption key management method includes: receiving a data registration request from a supplier terminal, determining a data identifier associated with the content data, encrypting a master key with a public key of the supplier terminal, and providing the supplier terminal with the master key encrypted with the public key of the supplier terminal, the data identifier, and a key update count value; receiving a subscription application related to the data identifier from a first subscriber terminal, encrypting the master key with a public key of the first subscriber terminal, and providing the first subscriber terminal with the master key encrypted with the public key of the first subscriber terminal and the key update count value; receiving encrypted content data encrypted with the symmetric key and a hash for the content data from the supplier terminal; and transmitting the encrypted content data and the hash to the first subscriber terminal.

Abstract: A data-sharing method, performed by a processor in a data-sharing apparatus including a blockchain ad a data subscription platform server, may comprise: registering, by the data subscription platform server, a data supply plan in the blockchain according to a request of a data supplier; registering, by the data subscription platform server, content data supplied from the data supplier; managing, by the data subscription platform server, data subscription rights of a data subscriber by using the blockchain according to a subscription request of the data subscriber; and supplying, by the data subscription platform server, the content data to the data subscriber.

Abstract: An encryption key management method includes: receiving a data registration request from a supplier terminal, determining a data identifier associated with the content data, encrypting a master key with a public key of the supplier terminal, and providing the supplier terminal with the master key encrypted with the public key of the supplier terminal, the data identifier, and a key update count value; receiving a subscription application related to the data identifier from a first subscriber terminal, encrypting the master key with a public key of the first subscriber terminal, and providing the first subscriber terminal with the master key encrypted with the public key of the first subscriber terminal and the key update count value; receiving encrypted content data encrypted with the symmetric key and a hash for the content data from the supplier terminal; and transmitting the encrypted content data and the hash to the first subscriber terminal.