Fleksibilni Internet servisi na bazi kontrole kašnjenja i

expected since both BPR and BPR + rely on the information about the backlogged packets
to make a scheduling decision. When a network is underutilized, buffers in routers are
empty most of the time and schedulers are not able to provide desired delay
differentiation. However, in the case of an underutilized network delay differentiation is
not needed because all packets experience low delay.
5.3.2. Influence of load distribution
In this scenario we varied the load distribution between throughput-sensitive and
delay-sensitive classes while maintaining the total load constant and equal to 100 % of
the output link’s capacity. Achieved average delay ratios are shown in Fig. 13.
Fig. 13. Average delay ratio achieved by BPR and BPR + for various traffic load distributions and
delay differentiation parameters δ.
It would be ideal if the achieved average delay ratio would not depend on the load
distribution between classes. However, both BPR and BPR + are, to a certain degree,
dependant on the traffic load distribution. The traffic class that constitutes larger portion
of the total traffic load is likely to experience higher delay than in the case of ideal delay
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