Method for managing control right, client device thereof, and master device thereof

1: This control management method in a n mirroring connection environment is disclosed. The master device according to an embodiment of the present invention for controlling at least one of the master device and the mirroring service from at least one of the plurality of client devices to mirror the display unit, the first screen displaying a first screen, receiving a request at least one of the groups, the control unit granting the requested privilege in response to the request to at least one of the plurality of client devices, and receive the request, and a communication unit for transmitting the response.