Performance Bounds for Flow Control Protocols 1

In this paper, we discuss a simple conceptual framework for analyzing the ow of data in integrated services networks. The framework allows us to easily model and analyze the behavior of open loop, rate based ow control protocols, as well as closed loop, window based ow control protocols. Central to the framework is the concept of a service curve element, whose departure process is bounded between the convolution of the arrival process with a minimum service curve and the convolution of the arrival process with a maximum service curve. Service curve elements can model links, propagation delays, schedulers, regulators, and window based throttles. The mathematical properties of convolution allow us to easily analyze complex conngurations of service curve elements to obtain bounds on end-to-end performance. We demonstrate this by examples, and investigate tradeoos between buuering requirements, throughput, and delay, for diierent ow control strategies.