Arbitration
A standard problem in using crossbar switches is that of setting the cross-points. In the classic telephony application of cross-bars, the crosspoints are closed and open as the telephone calls come and go. In Asynchronous Transfer Mode or packet switching applications, the crosspoints must be made and broken at each decision interval. In high-speed switches, the settings of all of the cross-points must be determined and then set millions or billions of times per second. One approach for making these decisions quickly is through the use of a wavefront arbiter.
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