High-speed ATM switching architecture using small shared switch blocks

This paper proposes a compact high-speed ATM switching architecture that employs a novel arbitration method. The N × N matrix shaped crosspoint switch is realized with D small switch blocks (SSBs). The number of crosspoints and address comparators is reduced from N^-2 to (N/D)². Each block contains N/D input lines and N/D output lines. The association between output lines and output ports is logically changed each cell period. This arrangement permits each input port to be connected to N/D output ports in each cell period. Output-line contention control is realized block-by-block so high-speed operation is realized. The traffic characteristics of the proposed switch architecture are analyzed using computer simulations. According to the simulation results, the cell loss rate of 10^-8 is achieved with only 100-cell input and output-buffers under the heavy random load of 0.9 for any size switch. The proposed ATM switching architecture can construct the Gbit/s high-speed ATM switch fabric needed for B-ISDN.