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

interoperability tests are required to ensure that the implementations conform to the
speci cations and deliver the promised performance. Another step to make the service
more attractive in the cost-performance tradeo is to demonstrate that a large class
of applications can be made to run over the service. Currently, ABR is promising for
two key internet applications: le transfer and the world wide web. It is interesting
to see if ABR can support variable quality voice and video. ABR multicast is also
another pre-requisite for supporting a wider class of applications
Another issue with ATM backbone scenarios is that ABR provides control only
upto the edge of the ATM network. It is possible that the edge router can use the
ABR rate feedback information to pace TCP tra c. This will carry the beni ts of
ABR to applications (i.e., end-to-end).
The proliferation of high-speed networking will increase the demand for high qual-
ity of service (QoS) on access network technologies like wireless and DSL (ADSL, 56
kbps modems etc). Such technologies are characterized by low bit rates and high
error rates. The implication of the mapping of ATM on such technologies is that traf-
c management has to deal with the e ect of uniform errors (due to the underlying
technology) as well as burst errors (due to congestion). Another scenario is that of
satellite networks where the delay is large, the bit rates are smaller, and the satellite
technology imposes rigid design constraints. Special schemes are required to handle
such scenarios correctly.
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