Priority queueing strategies for traffic control at a multichannel ATM switching system

The authors discuss the problem of furnishing an ATM-based B-ISDN (broadband ISDN) with two bearer services supporting different grades of transfer quality. By so doing, one is able to improve the utilization of network resources and provide a higher degree of flexibility. This is achieved by dynamically allocating network resources using priority classes. Several different loss priority queueing strategies are considered, namely complete sharing with push-out, complete sharing with push-out and head-of-the-line, partial buffer sharing, complete buffer partitioning but complete bandwidth sharing, and complete partitioning. A multichannel system model is developed for performance evaluation of these schemes. The authors develop performance bounds and compare these schemes in terms of performance and implementation complexity. They find that several-orders-of-magnitude improvement in the loss probability can be achieved for the high priority class with little impact on the low priority class performance