Even those that were sceptical about the application of Gallium Arsenide technology to high-speed computing conceded that it was likely to find favour in the telecommunications world, and GaAs pioneer has Vitesse Semiconductor Corp, Camarillo, California has come out with a major communications offering in the shape of the MegaSwitch VSC864, a 64 by 64 Crosspoint switch supporting data rates up to 200Mbps – claimed to represent a four-fold improvement in speed performance over existing Siliconbased crosspoints. The VSC864 is intended for data distribution for telecommunications, computer networks and multiprocessing environments, particularly as the core of central switching networks in large multiprocessor computer systems. It can also be implemented as a Sonet STS-3 protection switch in telecommunications systems, and for building large networks of personal computers, workstations and mainframes communicating via higher speed TAXIchip links. Any of the 64 inputs of the VSC864 can be switched to any, some, or all of its 64 outputs and it can be operated in either asynchronous flow-through mode or synchronous clocked mode through the use of its input and output data registers. In flow-through mode the data propagation delay is less than 7nS, Vitesse says. The outputs can drive 25 Ohm double-terminated buses with cutoff drivers, so that the device can be cascaded to create larger crosspoint switches. In normal operation, the traffic pattern in the VSC864 is controlled by data previously stored in 64 7-bit control registers, with each register corresponding to an output channel. A write mode is provided whereby any or all of the signal paths can be reconfigured and altered simultaneously from holding latches via a global strobe input. The device features industry standard ECL input-output levels and operates from a standard -2.0V power supply, typically dissipating less than 8W. Available now, it is $1,196 for 100-up.
