The effect of bottleneck service rate variations on the performance of the ABR flow control

One of the main features of ABR services is the employment of a rate-based flow control mechanism. Feedback from the network switches to the end systems gives users the information necessary to adjust their transmission rates appropriately according to the current network load. This type of control has been investigated to some extent, assuming a constant transmission capacity on a bottleneck link. In this paper we develop a discrete-time analysis to study the effect of bottleneck service rate variations on the performance of the ABR flow control mechanism. Looking at real systems, such variations occur on the one hand due to the establishment and release of ATM connections and on the other hand due to the varying bandwidth demand of VBR connections. To model the rate variations, the bottleneck service rate is assumed to follow a general probability density function.