The Bell-Northern Research arm of Northern Telecom Ltd claims to have perfected a means of switching digital traffic at Terabits per second speeds – which will be a requirement of multimedia networks of the future, and plans to demonstrate it at the International Switching Symposium in Berlin next week. The company is building an experimental model with potential switching capacity of 160Gbps, compared with the 40Gbps speeds of the fastest current Asynchronous Transfer Mode switches. The Tbps switch would use 32 satellite Asynchronous Mode switches running at 40Gbps to communicate through a passive optical core consisting of a mesh of optical fibres to provide high-speed interconnection of 32 port cards around the core. Each port card includes an optical splitter to duplicate incoming signals and deliver them to the core, and an optical selector to direct signals from the core to the appropriate output port – the 32 selectors all receive data streams from all transmitting splitters simultaneously and pick the right one under program control. Wavelength Division Multiplexing is used: the data stream is sent on four separate wavelengths over each switching path, and the combination is claimed to reach a peak rate of 1.28Tbps.
