Design and performance evaluation of a distributed knockout switch with input and output buffers

A high-capacity switch is an essential component for the success of broadband ISDN. A nonblocking ATM switch with input and output buffers is proposed and its performance is evaluated. The proposed switch is a modified version of an existing distributed-knockout-switch. In the proposed switch architecture, an input port with a nonempty queue always sends a cell to the switch at the beginning of each time slot. The cell sent out from an input port reaches either its destination output port (if it wins the contention) or a different input port (if it loses). A priority scheme is adopted to preserve service-cell sequencing. A cell is discarded if it loses a predetermined number of consecutive contentions. A modified architecture which can provide multicast service is also presented. Simulations are performed to evaluate the proposed switch architecture under both uniform- and hot-spot nonuniform-traffic models