before every effort is made to direct the message toward its target processing unit according to a further embodiment of the invention the message that has to be transferred between the processing unit 230 and the processing unit 220 may include a priority identifier indicating that the message is assigned a highest real time priority value suppose that in order to transmit the message to its target virtual address the processing unit 230 wants to transmit the message to the processing unit 240 which is currently receiving another message with a lower priority from the processing unit 210 in such a case the transmission of the message with the lower priority would be interrupted in favor of the message with the higher priority in this way the network provides a near real time behavior and minimizes the time needed for a routing procedure fig2 c shows a block diagram of a further embodiment of the invention featuring a circuit switch according to this ideal embodiment a message path is established connecting a plurality of processing units between the source processing unit and the target processing unit the routing of the message from the processing unit 230 to the processing unit 220 is realized by a message path connecting the processing unit 230 with the processing unit 240 connecting the processing unit 240 with the processing unit 250 and connecting the processing unit 250 with the processing unit 220 the established communication path is indicated by the arrows 260 262 and 264 in this circuit switch mode the connection 260 between the processing units 230 and 240 is.