Traffic models and admission control for variable bit rate continuous media transmission with deterministic service

In this paper we address the problem of call admission based on general descriptions of stored continuous media (CM) flows. We show that such an approach to call admission can result in a very high resource utilization that can be significantly higher than that produced when using time-invariant flow descriptions. We present the admissibility conditions for flows, where packets are scheduled according to the earliest-deadline-first (EDF) scheduling policy. We further present an algorithm for testing for admissibility of a new flow whose computational complexity is linear in the number of flows and in the linear segments used for flow description. Last, we present an algorithm for producing a parsimonious flow description which produces most of the benefit of the best general description while requiring a small number of linear segments. Simulation shows that this improves the network resource utilization as much as 200–250% over the best possible utilization achieved using any time-invariant workload function. A significant improvement results even when the workload is smoothed.