Title (Ammar) : QoS and TCO: A Relationship Study.
In IP networking, delivering real time services at a defined level of Quality of Experience (QoE) requires implementation of stringent Service Level Agreements (SLAs). This can be achieved in two ways: (1) running the network at low utilisation, and (2) configuring and applying Quality of Service (QoS) policies. These alternative approaches imply rather different levels of network efficiency and, hence, different CAPEX costs to support a given level of demand. In addition, applying a QoS policy has an OPEX cost component, given the need for suitably qualified staff to review and update policies with network growth and service introduction. A significant challenge is to quantify the cost benefit of these two alternative approaches. This research is aimed at developing a methodology to quantify the cost benefit of QoS policies on routers and evaluate bandwidth vs. QoS alternatives for distributed hardware router architectures, using QoE as an assessment criterion. This will help network providers and enterprises understand the Total Cost of Ownership (TCO) of delivering services at a defined level of QoE. To this end a lab is constructed to analyse the impact of QoS policies on QoE in a controllable and reproducible manner. The lab can be configured to investigate a range of router architectures and loaded with a heterogeneous mix of services in order to evaluate the loading efficiency at different levels of QoE. Results on the loading efficiency of alternate policies are used as the basis for TCO evaluation.