BANDWIDTH QUANTIZATION AND STATES REDUCTION IN THE BROAD-BAND ISDN

If a network supports only certain rates, we say its bandwidth is quantized. In a quantized-bandwidth network, a customer may be forced to use the next higher rate if the requested rate is not supported, The result is a higher blocking probability and a lower throughput. The throughput loss due to quantization-called the quantization loss-and its related issues are the focus of this paper. We show that the quantization loss is insensitive to capacity scaling and traffic loading. More important, it is hardly as big as is thought, Even for a network, such as ATM, intending to support a continuous bit rate, bandwidth quantization can be a powerful tool for states reduction. States reduction, we show in the paper, is indispensable for solving many problems, such as routing and capacity planning, of a broadband network.