Abstract: The problem is to facilitate alteration of a transmission line in the case where the target device establishes a connection on the bus and thereby secures a transmission line in order to transmit stream data in a network of the IEEE 1394 scheme or the like. Stream data outputted from an output device 1 connected to a predetermined network is received by an input device 2. When the output device or a different device has sent an order for setting so that output data of the output device 1 may be inputted to a data input section 2b of the input device 2, the input device 2 conducts input setting based on the order. In addition, when the device which sent the order has sent an order to cancel the input setting, the input device 2 conducts processing of canceling the input setting.