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Examples

In this section we illustrate the ramifications of the differences between Equation 12 and Equation 6 with a small example.

Table 2 shows the experimentally derived baseline throughputs of two identical competing nodes as a function of transmission rate. This provides an estimate of baseline throughput for various transmission rates.

Using these values, we compute the throughputs when I contains four competing nodes, one communicating at 1 Mbps, one at 2 Mbps, and at 11 Mbps. These are shown in Table 3. The achieved throughput of the slower nodes is less under time-based fairness than under throughput-based fairness. Under time-based fairness, the 1 Mbps and 2 Mbps nodes achieve the throughput they would have achieved of all four nodes were running at their speed. The 11 Mbps nodes achieve considerably higher throughput under time-based fairness, and the total throughput improves by $82\%$.



Godfrey Tan 2004-05-04