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

An oscillation-free steady state performance. The frequency of oscillations is
a function of 1 ; z, where z is the load factor. In steady state, z = 1 , the
frequency is zero, that is, the period of oscillations is in nite.
Simple to implement.
Uses the load factor as the primary metric, and does not use the CCR eld.
The single \fairshare" threshold is similar to the EPRCA concept. This allows
the scheme to have an O(1) space complexity and easily converge to fairness
under conditions of constant demand and capacity.
The drawbacks of the scheme include:
The convergence time of the scheme is longer since it uses parameters whose
values are chosen conservatively.
Since the algorithm uses a binary indication bit in very congested states, it is
prone to unfair behaviors [3].
4.8 Phantom
This scheme was developed by Afek, Masour and Ostfeld at the Tel-Aviv Uni-
versity [3]. An important design goal in this work is to develop a constant space
congestion avoidance algorithm, while achieving max-min fairness, and good tran-
sient response.
4.8.1 Key Techniques
The key idea is to bound the rate of sessions that share a link by the amount of
unused bandwidth on that link. The scheme uses the concept of a Phantom session
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