Analysis and optimization of pacing window flow control with admission delay

An analysis is provided of queuing models in virtual route networks for which a pacing window flow control mechanism is used. An input queue is introduced to describe the waiting system where messages prevented from entering the network are stored in first-come, first-served manner. Both finite and infinite capacity are considered. The model leads to a Markovian queuing system, which is fully solved by matrix-geometric methods. The analytical results show that the optimal window size which maximizes the power criterion including the admission delay is nearly twice the number of hops (nodes of the network) for the model with infinite input-queue capacity. This rule of thumb also applies to the finite-capacity model with certain restrictions. Simulations are presented to verify the analytical results.<>