Patent ID: 11876897
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Digital communication (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 0:
1. A right-holder terminal of a right holder of a content, comprising:
a processor; and
memory,
wherein the memory includes computer executable instructions that when executed by the processor cause the processor to configure the right-holder terminal to:
store a key pair for an electronic signature including a right-holder secret encryption key and a right-holder public decryption key and a content decryption key for decryption of the content in the memory;
verify whether a permission request received from a user terminal of a user of the content satisfies a permission condition for the content, wherein the permission request is acquired from a blockchain by the right-holder terminal after the user terminal broadcasts the permission request to a network and causes a block including the permission request to be added to the blockchain, wherein the network includes at least the right-holder terminal, the user terminal, and the blockchain; and
when the permission request satisfies the permission condition, encrypts the content decryption key by using a public encryption key included in the permission request acquired from the blockchain, and transmits permission information including the encrypted content decryption key to the user terminal after electronically signing the permission information with the right-holder secret encryption key of the key pair, wherein the permission information is stored in the blockchain after the right-holder terminal broadcasts the permission information to the network and causes a block including the permission information to be added to the blockchain.