A plurality of MFPs are connected to a data transfer system, and one of the MFPs functions as a representing MFP. The representing MFP monitors a connection status of the MFPs and a PC to the data transfer system. Upon detection of a change in the connection status, the representing MFP assigns the PC connected to the data transfer system after the change to each of the plurality of MFPs in an order up to a maximum number of PCs that can be connected, and has information necessary for carrying out data transfer to the PC be stored in the MFPs connected to the data transfer system in a distributed manner.