EFFECTIVE BANDWIDTHS WITH DIFFERENT QUALITY OF SERVICE REQUIREMENTS

The concept of an effective bandwidth for controlling ATM networks with multiple source classes is quite well understood, for example see [6, 5, 7]. However, there are two main gaps in the literature. Firstly, the concept of an effective bandwidth has mainly been investigated under the cell loss quality of service (QoS) measure describing the proportion of time that cell loss occurs, which we call the resource based QoS measure. We feel that it is essential to extend the concept to the QoS measure describing the proportion of cells that are lost, which we call the stream based QoS measure. Secondly, there has been no investigation of effective bandwidths when the different source classes require radically different qualities of service. This investigation is important because certain types of call will require almost error-free transmission (such as HDTV or real-time data transfer) and other calls will be willing to receive a much lower QoS for a reduced price (such as telephony). The following work applies to any stationary source model with a finite number of possible bandwidth requirements and the bufferless resource model of Hui [6].