This European Standard describes: . the system physical structure; . the system control signals, which implement an extension of the DiSEqC set of commands described in the .DiSEqC. Bus Functional Specifications Version 4.2, February 25, 1998; . the definition of identified configurations; . management of the potential collisions in the control signals traffic. Figure 1 illustrates the physical system configuration considered in this European Standard. Several satellite signal demodulators can receive signals from any of the input signalbanks of the LNB or the switch; the signals selected by the demodulators (or receivers) are transported via a single cable