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Soft Faults

Finally, we present in Figure 6 the numbers of soft faults incurred by all the studied policies. The first column presents the soft faults under constant threshold tex2html_wrap_inline490 and variable modem pool size. The second column presents the numbers of soft faults under constant modem pool size and variable threshold. All parameters are the same as for the corresponding plots in Figures 4 and 5. As we explained earlier, the number of soft faults is not an accurate indication of the performance of a policy--soft faults represent correct predictions that lead to successful disconnections. Nevertheless, we show the soft fault measurements for completeness. The reader can refer to these plots to confirm that the predictions made by CIRG and LRU were very often accurate--the number of soft faults is usually many times higher than the number of hard faults.

 

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Figure: Plots of soft faults for all traces under variable number of modems (first column) and variable threshold (second column). The parameters not shown on the plots are the same as those used in Figure 4 for the first column and in Figure 5 for the second column. The LRU and CIRG curves often coincide and cannot be distinguished.



Yannis Smaragdakis
Tue Apr 25 15:09:47 EDT 2000