Data transfer controlling method, content transfer controlling method, content processing information acquisition method and content transfer system

A system for transferring data in a Digital Rights Management (DRM) interoperable environment, the system comprising:

• a first device comprising a controller configured to receive a transfer request message from a client and subscribe to a specific event for receiving an event message from an importer;
• and
• a second device comprising an importer, the second device including memory and a processor configured to:
• receive a capability request message from a controller which receives a data transmission request message from a client, the data transmission request message requesting a data transmission;
• transmit to the controller, responsive to the capability request message, data describing a capability, wherein the transmitted data describing the capability is used to determine whether a transformation involved with the requested data transmission is possible and to form a chain for the data transmission;
• receive, from the controller, an importing request message, which requests import data and includes:
• a transmission session identifier identifying a transmission session, a transmitter identifier identifying a transmitter transmitting the data, and DRM information describing a second DRM system in a destination,
• receive the data from the transmitter, wherein the transmitter is any one of an exporter that exports data from a first DRM system or a transformer that transforms exported data into a specific format,
• import the received data into the second DRM system in accordance with policies of the second DRM system, based on the DRM information, and
• transmit, to the controller, the event message describing a status of a transmission of the data, wherein the event message includes at least one of a start element that indicates that the transmission has started, a completion element that indicates that the transmission has been completed, a progress element that indicates a progress of the transmission, and an error element that indicates an error in the transmission
• wherein receiving the data from the transmitter is based on a transmission protocol that supports transmission of multiple data items in a single session and supports variable frame sizes, wherein
• each data item is divided into multiple frames, each frame having a header of N bits, N being an integer greater than or equal to 2, the header indicating a length of a payload of the corresponding frame,
• an index identifying each data item is inserted before the header of a first frame of each data item,
• an end of each data item is indicated by a data separator constructed with a predetermined number of bits having first values, and
• an end of the transmission of the multiple data items is indicated by an end-of-transmission string constructed with a predetermined number of bits having second values.