PERFORMANCE ANALYSIS OF TRANSPORT PROTOCOLS OVER CONGESTIVE CHANNELS

We analyze a Markov model of the performance of transport protocols over congestive channels, which are channels whose delay and loss characteristics depend significantly upon the number of messages in transit. Such channels are typical of most store-and-forward networks, including the Internet. We present a general state transition framework for modeling various protocol policies and congestive channels, and for representing performance measures. Using this framework, we obtain a continuous-time Markov chain model of a protocol with simple policies. The Markov chain is solved numerically to obtain performance measures of interest to the user (response time, throughput, etc.), and of interest to the protocol designer (congestion in the channels, space available in the windows, etc.). The numerical solution technique yields not only the averages of these measures, but also their probability distributions. © 1990.