In a transfer device which mediates communication between first communication devices and a second communication device via a network, a first receiver unit receives collectively operation responses from the first communication devices, the operation responses being created to operation requests of the second communication device respectively. A first transmitter unit transmits collectively the operation responses received by the first receiver unit, to the second communication device as a destination of each of the operation responses. A second receiver unit receives collectively the operation requests which are sent to the first communication devices by the second communication device, from the second communication device. A second transmitter unit transmits collectively the operation requests received by the second receiver unit, to the first communication devices as respective destinations of the operation requests.