Abstract: A switched integrated wideband and narrowband multiservices digital network (FIGS. 1 and 2) is an ISDM providing universal information services based on wideband and narrowband voice, data, and video communications. It comprises a plurality of service areas (100, 101), each served by a central switching node (110). The central node is connected to a plurality of remote nodes (103) by feeder optical fibers (107) and a control bus extension (106). Network interface equipment (104) at subscribers' (102) premises is connected to remote nodes by distribution optical fibers (105). Each distribution fiber is wavelength-division multiplexed and carries modulated (pulse-analog, pulse-code, or differential pulse-code) wideband digital channels (205) and a multiplexed channel (206) comprising 32 time-division-multiplexed narrowband digital channels (207). One narrowband channel (207D) carries all signaling messages.

Abstract: A system for efficiently switching time multiplexed digital signals of different bit rates. A switch is described including switch modules each of which can switch data and/or voice 56 kilobit/second (kb) full-rate channels and 2.4 kb, 4.8 kb, and 9.6 kb subrate channels. All signals from incoming channels are stored in a signal memory and are transmitted to outgoing channels under the control of addresses stored in a control memory. The frame offset of each channel with respect to a standard superframe is detected and used to calculate the addresses to be stored in the control memory. Various arrangements are shown to minimize high speed signal and control memory requirements, and to simplify the process of generating control memory contents.