New models for admission control of priority traffic in ATM networks

Proposals for ATM connection admission control (CAC) algorithms are often based on real time calculation of the admissible load consistent with a given cell loss probability (CLP) and buffer length. These calculations rely on a wide range of analytical models, but the models rely on the analysis of two fundamental components of queueing behaviour: the burst scale component and the cell scale component, where the latter is always present and can be modelled by an M/D/1 queue. We present some new and accurate closed form approximations for the M/D/1 queue, which can be arranged to yield expressions for the cell loss probability, the admissible load and the buffer length. We use our results to derive expressions for traffic that may include both time and space priority cells.