Time-multiplexed switching network controller - uses memory unit to store current routing status and has several communications channels

The controller of a switching network for time multiphased data packets selects the routing of a message, as stored in its memory, and cheks that the message does get transferred along this route. The switching network (1) contains a number of communication channels (3) and is controlled and monitored by a computer (5). The controller (10) has two selectors (SJ1, SJ2) which cyclically scan each entry port (JE0, JE1...) and each exit port JS0, JS1...) of the network (3). The patterns appearing in these scans are passed to a comparator (16) which checks that the exit and entry of the message correspond with that stored in the memory (14), and previously determined by the network computer (5).