A switching system comprising a cross-point switch and a Delta network. The two switches are connected in parallel with common port adaptors. When a port desires a specified time reservation to another port, it sends a request message for the specified time over the Delta network to the requested adaptor...http://www.google.de/patents/US4814762?utm_source=gb-gplus-sharePatent US4814762 - Delta network control of a cross-point switch
