US Patent 11641356 Authorization apparatus, data server and communication system

An authorization apparatus includes a memory configured to store attribute information associating an identification information of data and information indicating an attribute of the data, the data being stored in a data server, a processor configured to generate an access token in association with an extraction condition to be used for extracting the data to be obtained by a terminal, and a communicator configured to receive a target access token from the data server, wherein when receiving the target access token, the processor is configured to extract identification information of data pieces satisfying the extraction condition associated with the target access token, and generate a list of identification information of the data to be disclosed to the terminal using a target access token, and the communicator transmits the list to the data server.