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The QoSbox Multimedia Networks Group Dept. of Computer Science University of Virginia |
Overview
The QoSbox is a configurable IP router that provides per-hop service guarantees on loss, delays and throughput to classes of traffic. There is no restriction on the number of classes or the specific service guarantees each class obtains. The novel aspects of the QoSbox are that (1) the QoSbox does not rely on any external component (e.g., no traffic shaping and no admission control) to enforce the desired service guarantees, allowing for incremental deployment, but instead, (2) dynamically adapts packet forwarding and dropping decisions as a function of the instantaneous traffic arrivals; also, (3) the QoSbox can enforce both absolute bounds and proportional service guarantees on queueing delays, loss rates, and throughput at the same time.
As shown in the above picture, the QoS guarantees are configured via a set of "tuning knobs," and there is no communication required between different QoSboxes in the same network. No admission control is needed. Thus, the QoSbox provides absolute and proportional service guarantees without requiring any additional support from the network. The user of the QoSbox (presumably, an ISP) only has to configure the QoS parameters, and place the QoSbox(es) at the bottleneck(s) in the network.
We have implemented the algorithms we envision for the QoSbox in the ns network simulator, and in the FreeBSD, NetBSD, and OpenBSD kernels, within the ALTQ and KAME packages.
The QoSbox is part of the Denali project for scalable communication services for the global network.
People
Grateful acknowledgments to Prof. Tarek Abdelzaher for his invaluable help in designing some of the algorithms in use in the QoSbox, to Kenjiro Cho for his advice regarding the implementation in PC-routers, and to Prof. Constantinos Dovrolis for allowing us to reuse and redistribute some of his ns-2 code.
The QoSbox project is supported by the National Science Foundation under grant numbers NCR-9624106 (CAREER), ANI-9730103 and ANI-0085955.
Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation or any other sponsor.
