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

mention this concept of fairness for bursty tra c, we do not use the concept further
in this dissertation.
3.3 Stable Steady State
The steady state of the system is a state where the goals of e ciency (congestion
avoidance) and fairness (max-min) have been achieved. The scheme should rst
be able to converge to a steady state from any set of initial conditions, provided
that the demand and capacity remain constant. Secondly, once the scheme reaches
optimal steady state operation, it should stay close to the optimal operation in spite
of asynchrony in feedback/response characteristics of the network. In other words,
the steady state oscillations between overloaded and underloaded states should be
minimal and bounded. An example of a desirable steady state operation is shown
(with respect to congestion avoidance, or e ciency alone) in Figure 3.1. Typical
steady states have a small amount of residual bandwidth to drain out transient queues
and reach the steady state operation of near-zero queuing delay and high throughput.
3.4 Transient Response
Figure 3.5: Transient vs Steady State Performance
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