Patent ID: 7724769

Claim:
A data transmission system including first and second media devices that communicate with each other according to a predetermined transmission protocol and a control device that controls the first and second media devices according to a UPnP AV protocol different from the predetermined transmission protocol, the UPnP AV protocol used in generating and managing of a virtual connection and the predetermined transmission protocol used in generating and managing of a real connection, the two protocols being defined independently of each other, the control device comprising: a virtual connection establisher which establishes a virtual connection in accordance with the UPnP AV protocol between the first and second media devices; and a communication controller which transmits instruction data to the first media device for instructing the first media device to receive media data from the second media device or transmit media data to the second media device by using the virtual connection, the instruction data including information of the virtual connection established by the virtual connection establisher; the first media device comprising: a real connection establishment requester which generates a real connection establishment request for requesting the second media device to establish a real connection for receiving or transmitting the media data in accordance with the predetermined transmission protocol in a case of receiving the instruction data, and which transmits the real connection establishment request to the second media device in accordance with the predetermined transmission protocol, the real connection establishment request including information of the virtual connection established by the establisher; and a first communicator which receives the media data from the second media device or transmits the media data to the second media device by using the established real connection; and the second media device comprising: a real connection establisher which establishes the real connection with the first media device on a basis of the real connection establishment request from the first media device in accordance with the predetermined transmission protocol when the information of the virtual connection included in the real connection establishment request indicates the virtual connection established by the virtual connection establisher, the established real connection being related to the virtual connection established by the virtual connection establisher; and a second communicator which transmits the media data to the first media device or receives the media data from the first media device by using the established real connection.