QoS control versus generous dimensioning


As the world of telecommunications embraces IP as the route to truly converged networks there are, for pioneering national telecommunications operators, difficult engineering requirements to address — in particular, how to deliver high-quality session-based services over a connectionless infrastructure. The falling price of commodity bit transport leads some to suggest that simply providing high levels of capacity will be enough to provide effective quality in the ‘new wave’ networks, and that sophisticated approaches, such as explicit bandwidth reservation, are an expensive luxury. We discuss the implications of operating a network under the two very different paradigms of QoS control (bandwidth reservation under connection control) and generous dimensioning, focusing at first on a pure PSTN replacement, before considering the implications for a true, converged multiservice platform. We conclude that these two approaches give rise to different services. In an increasingly competitive world we might choose either approach for different commercial reasons, but we should not be misled into believing that generous dimensioning gives us the same service as QoS control.

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Johnson, D.M. QoS control versus generous dimensioning. BT Technol J 23, 81–96 (2005). https://doi.org/10.1007/s10550-005-0009-2

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