On Defining, Computing and Guaranteeing Statistical Quality-Of-Service In High-Speed Networks

• Authors: R. Nagarajan;J. F. Kurose;D. Towsley
• Venue: On Defining, Computing and Guaranteeing Statistical Quality-Of-Service In High-Speed Networks
• Year: 1990

Future high-speed networks (HSNs) are expected to support a wide variety of services such as voice and video and provide a guaranteed quality-of-service (QOS). In this report, we examine in detail the issues of computing and guaranteeing QOS. Traditionally, the computation of user-oriented performance criteria such as the average delay has been carried out via steady state analysis of queueing theoretic models of communication net- works. In this paper, we show that the steady state analysis is not entirely sufficient for QOS purposes in future high-speed net- works as it yields long run performance measures that are not appropriate for envisaged applications in HSNs. New QOS criteria for such applications are proposed and their computation detailed for some simple queueing models. One {\em key result} of this paper is that for {\em Poisson traffic the carried load in the network may be maintained at fairly high levels}, in comparison to those predicted by standard steady state analysis, while pro- viding fairly good QOS (as defined in this report) to applications. On the other hand, it appears that for {\em correlated traffic (such as for ADPCM packet voice) large values of the carried load may not be supportable while providing an acceptable QOS}.