A communications system, with a network, is usable to transmit at least image data to at least one illuminating device. The illustrating device illustrates a printed image location in a printing machine. A network is provided for the control and/or monitoring of the printing machine. A network for the communication of data to be processed in a pre-printing stage is also provided in that pre-printing stage, which prepares that image data. These two networks are connected to the same signal line or transmission link or are each constructed identically, with respect to their data transmission properties. The communications system, with the network, can control or monitor a printing machine having a number of sections, with at least two of these sections having a section controlling device. These section controlling devices are connected to the network, and control or monitor their respective sections. The network has the same data transmission properties in each of these sections.