INTEGRATED CIRCUIT AND MESSAGE SWITCH.

The problem of integrating the functions of a circuit and a message switch was examined on three levels. The first consisted of identifying functions in both switching modes which had similar over-all demands, such as headersignalling analysis, calledrouting determination, etc. The second consisted of examining methods of implementing both common and dissimilar functions via a common control system. The third level consisted of examining a modular organization which offered an ability to change the number of terminations andor the connected data load, and yet maintain an integral module which can be connected to other modules so that the resulting configurations can operate with a terminating quantity greater than that of one module. A stored program processor control was developed which constitutes a major system within the module. The controller will apportion both circuit switched and message switch traffic service as a function of the degree of load on the module, the available trunks, the mix between store and forward and circuit switched traffic at certain times, and similar considerations. A concept for a modular program for the controller was developed, as well as some considerations on terminal types, procedures and applicable signalling and supervision. A space division switching technique was selected which uses solid state integrated circuit cross points, with fast response time and sufficiently wide band pass to cope with analog andor digital traffic. Author