Fast and accurate estimation of ATM quality-of-service parameters with applications to call admission control

It is demonstrated how fast and accurate estimates of quality-of-service (QOS) parameters can be obtained for an ATM multiplexer queueing model fed by multiple Markovian traffic sources. This has been achieved by constructing a simple approximation of the buffer overflow probability, which involves computation of two parameters based on the theory of large deviations. Upper bounds on other QOS parameters, such as cell loss ratio, mean cell delay and cell delay variance, can all be derived from this estimate. It is shown that this approximation is much more accurate than the pure effective bandwidth one, which ignores the statistical multiplexing gain due to a large number of sources. One attraction of the proposed method is that the speed of computation of this approach is independent of the size of the system. Thus the authors´ analytical techniques can be implemented fast enough for real-time admission control in ATM networks