On the accelerated simulation of VBR virtual channel multiplexing in a single-server FIFO buffer

While direct cell-level simulation accurately predicts congestion in cell-switched networks, excessive run-times are often required to obtain significant results. Methods of Accelerated simulation have therefore been developed, examples of which include the cell rate technique (which represents the discrete cell-streams as continuous fluids) and the histogram method (which merges the multiplexed streams into an aggregate cell-rate histogram and performs independent statistical analysis on each bin). The current work applies both these techniques to a simple ATM multiplexer and explores their respective advantages and drawbacks. While the cell-rate method provides accurate predictions under a rapidly varying bit rate, the histogram method is more successful under quasi-static conditions. This suggests the possibility of a hybrid cell-rate/histogram model which is accurate at both extremes.