Quality of Service in Next Generation Computer Networks


We are currently witnessing unprecedented mergers in the telecommunications industry. This reflects the belief that multiple telecommunications services can be more efficiently offered over a single integrated network than over separate dedicated facilities. In this project, we study the gains achieved by various amounts of resource sharing at the network access point. Integration of heterogeneous services requires that the network be able to guarantee performance to a bursty bit source by reserving less bandwidth than it’s peak rate. This challenge involves three tasks: source characterization, contract negotiation, and contract enforcement. A great deal of progress has recently been made on the first and third tasks, but the second task remains relatively unaddressed. In this project, we model the multiplexing of multiple heterogeneous bit steams at the network access point and investigate the dependence of multiplexing gains on the burstiness of each source type and on the diversity of the source types. The results will provide mechanisms for the network to use source characterizations to negotiate a contract with the user and to understand a fair price for this service. We believe these issues will be crucial to the offering of guaranteed performance services in future telecommunication networks.

Principal Papers:

Multiplexing Gains in Bit Stream Multiplexors (with I. Sidhu), IEEE/ACM Transactions on Networking, vol. 3 no. 6, December 1995, pp. 785-797.

The Variation of Optimal Bandwidth and Buffer Allocation with the Number of Sources (with K. Jogi, C. Shi and I. Sidhu), IEEE/ACM Transactions on Networking, vol. 12 no. 6, December 2004, pp. 1093-1104.

Average Rate in a M/M/1 Processor-Sharing Queue (with N. Chen), IEEE American Control Conference (ACC), Portland, Oregon, June 2005, pp. (abstract, paper)

Additional Papers:

A Loss Model for VBR Sources in ATM Networks (with A. Khan), ICAST, Chicago, Illinois, March 1995. (paper)

Packet Erasure FEC on ARQ Protocols (with T. Kostas ), SPIE ITCom Internet Performance and Control of Network Systems, Boston, Massachusetts, July 2002, pp. 126-137. (abstract, paper)

Portions of this work were supported by DARPA and NSF. Any opinions, findings, 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, DARPA, or IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. One print or electronic copy may be made for personal use only. Permission must be obtained from the copyright holder for systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in these papers for a fee or for commercial purposes, modification of the content of these papers, reprinting or republishing of this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, and to reuse any copyrighted component of this work in other works.


Scott Jordan (6/24/2005)