On providing blocking probability and throughput guarantees in a multi‐service environment

As the Internet evolves from a packet network supporting a single best effort service class towards an integrated infrastructure supporting several service classes—some with QoS guarantees—there is a growing interest in the introduction of admission control and in devising bandwidth sharing strategies, which meet the diverse needs of QoS‐assured and elastic services. In this paper we show that the extension of the classical multi‐rate loss model is possible in a way that makes it useful in the performance analysis of a future admission control based Internet that supports traffic with peak rate guarantee as well as elastic traffic. After introducing the model, it is applied for the analysis of a single link, where it sheds light on the trade‐off between blocking probability and throughput. For the investigation of this trade‐off, we introduce the throughput‐threshold constraint, which bounds the probability that the throughput of a traffic flow drops below a predefined threshold. Finally, we use the model to determine the optimal parameter set of the popular partial overlap link allocation policy: we propose a computationally efficient algorithm that provides blocking probability‐ and throughput guarantees. We conclude that the model and the numerical results provide important insights in traffic engineering in the Internet. Copyright © 2002 John Wiley & Sons, Ltd.