Performance comparison of two window flow control schemes with admission delay

A performance comparison of two window flow control schemes, e.g., the pacing and the sliding window protocols, over a virtual route network with an input queue included is presented. The input queue is introduced into the model to describe the waiting system where messages prevented from entering the network are stored in a first-come first-served manner. The model is shown to lead to a Markovian queuing system, which is solved through approximations by using the appropriate solution methods. The results indicate that the optimum window size that maximizes the power criterion is empirically determined and becomes nearly twice the number of hops (nodes of the network). It is also indicated that, although the average number of messages in the network is higher for the pacing window case, when the input queue delay is taken into consideration the overall performance of the pacing window protocol is better than that of the sliding window