Methodology for derivation of network resources to support video-related services in ATM-based private wide-area networks

Abstract

The statistical mode of operation of asynchronous-transfer-mode (ATM) networks can lead to congestion which, in turn, leads to a degradation in the quality of service (QOS) of calls. Normally, congestion manifests itself by overflow in the input or output controllers of switches. An outstanding research issue relating to ATM networks, therefore, is resource management; i.e. determining the optimum network resources, in terms of link bandwidth and buffer capacity in switches, that are required for a call which guarantees a defined QOS, even under high-network-loading conditions. The two most important QOS parameters associated with a cell are cell-loss rate and cell-delay variation. In practice, the parameters are interrelated and make conflicting demands on the available resources. Video services, for example, are sensitive to both parameters and hence it is necessary to consider the combined parameters when allocating resources for such services. The paper describes a new method for deriving the optimum resources required for video-related services in an ATM-based private network to guarantee specific QOS requirements.