A SELF-ROUTING MULTISTAGE SWITCHING NETWORK FOR BROAD-BAND ISDN

Many switching networks have been proposed for broadband ISDN [1]. Switching networks which are capable of achieving maximum throughput of 100% either have large internal speedup [2], [3] or require large amounts of hardware [4], [5]. For example, the input-output difference self-routing network [3] and ATOM switch [2] require large internal speed-up factors. In order to maintain the non-blocking property, the internal speed of an N × N switching network has to be N times higher than the maximum rate of the incoming packets. The internal speed can be reduced by introducing parallel switching planes thereby increasing the hardware complexity. In this paper, we propose a new switching network that approaches a maximum throughput of 100% as buffering is increased. This self-routing switching network consists of simple 2×2 switching elements, distributors, and buffers located between stages and in the output ports. The proposed switching network requires speed-up of two. The structure and the operation of the switching network are described and the performance of the switching network is analyzed. © 1990 IEEE