Probing strategies for distributed admission control in large and small scale systems

The aim of this article is to propose and analyse measurement-based admission control schemes. We distinguish between large-scale and small-scale systems, where scale is measured in the number of concurrent applications that can run simultaneously. For large scale systems, we show that simple end-user probing strategies, based on ECN-type feedback provided by the network, achieve a good utilisation/quality trade-off. We explicitly take account of feedback delay, and use limiting results for assessing performance. We illustrate the benefits of using ECN-type feedback rather than relying on loss. For small-scale systems, the previous strategies are no longer adequate and we propose alternative, more gradual probing strategies.