ABSTRACT

SUMMARY Input and output queueing nonblocking switch with feed-back loop is proposed in order to reduce the system delay. It has b head of the line (HOL)’s and b output ports feed-backed into the HOL’s of feed-back loop. The cell which receives backpressure over threshold is switched and enters one of these HOL’s through a feed-back loop. It provides the cell, which should wait behind the HOL of input queue until the cell in that HOL is served, with opportunity to be served immediately by vacating the HOL of the input queue. We obtain the mean system delay and consider the effect of the size of b by computer simulation. As the results, it is shown that proposed switch with appropriate size of b can reduce the system delay compared to the conventional switch.