Shared concentration output queuing switch for multiple priority classes

In B-ISDN, it is important to handle a variety of traffic having different loss probability requirements by using the same network. Since the shared concentration output queuing (SCOQ) switch has shared transmission networks, focus has been on its switch. In multimedia communications, the QoS (quality of service) is required and satisfied. Moreover, it is important to satisfy the requirement for cell loss probability. The switch has the advantage that the number of switching elements is small. However, it is not enough to correspond to priority classes. In this paper, we propose the SCOQ switch model for multiple priority classes, which is structured with a batcher network and independent banyan networks for each class and output buffers. We evaluate the cell loss probability and mean waiting time by computer simulations and analysis. The cell loss probability of the high-priority class can be reduced since more high-priority cells have priority to be transmitted to output buffers than low-priority cells. As a result, we show that the proposed model is useful in satisfying different requirements of the cell loss probability for multiple priority classes.