Traffic Management for the Available Bit Rate (ABR) Service in ...

espectively. The target delay T 0 is set at 100 microseconds for LAN simulations
and 500 microseconds for WAN simulations, and the queue drain limit factor
(QDLF ) is set at 0.5.
9. All sources, including VBR sources are deterministic, i.e., their start/stop times
and their transmission rates are known. The bursty tra c sources send data
in bursts, where each burst starts after a request has been received from the
client.
6.22.2 E ciency
Figure 6.7: One source con guration
The very rst test to verify e cient operation is to use a single source con guration
as shown in gure 6.7. A scheme that does not work for this simple con guration
is not worth further analysis. The source is active over the entire simulation period.
Figure 6.11 illustrates that ERICA achieves the required e ciency, since the source
rate rises to almost fully utilize the link. Observe that there are no rate oscillations
in the steady state, and that utilization is at the target utilization goal (95%).
The same con guration has also been simulated to examine the e ciency of ER-
ICA+. As seen in gure 6.12, the source rate rises to fully utilize the link (100%
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