Multicasting in the SCOQ switch

SCOQ, a high performance fast packet switch with shared concentration and output queueing supports, point-to-point transmissions only. The incorporation of multicast (point-to-multipoint) functions require packet duplications. If the copy network were placed on the feedforward path of the switch, it is not transparent to, and can interfere with, point-to-point switching. By placing the copy network in the feedback position, its operation can be made transparent to the point-to-point information transfer. The copy network incorporated onto the SCOQ switch is non-blocking even without an arbitration or selection network. Contrary to the feedforward approach in which the input buffers must be centrally controlled, with the copy network in the feedback loop, the input buffers all operate independent of each other