Size-based Differentiation to Enhance System and User Perceived Performance for Networks Supporting Best Effort Traffic

Mr. S. Jay Yang
Dept. of Electrical and Computer Engineering
The University of Texas at Austin

Friday, September 28th, 1:30 PM, ACES 3.408

scyang@ece.utexas.edu


Abstract

A fundamental, yet usually ignored, challenge to evolving data networks is enabling better Quality of Service (QoS) for best effort traffic. While over-provisioning network resources was considered to be a simple, possibly less expensive solution, the lack of fairly predictable Internet traffic and growth model makes it almost impossible to ensure an "efficiently" dimensioned network. Even if a single carrier could overcome this problem and appropriately provision his network, the heterogeneity of the inter-networking infrastructure would make coordinating inter-carrier agreements to avoid mismatches exceedingly difficult. Recognizing that over-provisioning is at most a partial solution, we approach the problem by "intelligently" share resources that extends the "dynamic range" of traffic loads where networks can ensure adequate system and user perceived performance.

Best effort service involves for the most part transfers of files for which the transmitter has a-priori knowledge of the file's size. Two plausible QoS measures for such transfers are delay and bit transmission delay (BTD), i.e., delay/file size, among which the latter captures more "savvy" users who recognize that big files take longer to transfer. In this talk I will discuss how one might design size-based transport mechanisms and routing algorithms to enhance the overall network and user performance in a cooperative environment. Our view is that by simply introducing such size information, one may produce a "robust" best effort network that achieves better performance for all transfers for a range of traffic loads, even with the existence of impatient users.

Biography

Shanchieh Jay Yang received his B.S. degree in Electronics Engineering at the National Chiao-Tung University (Taiwan) in 1995. After working as a research assistant for Professor C. Bernard Shung in Taiwan, he then entered the Department of Electrical and Computer Engineering at the University of Texas at Austin, and received his M.S. degree in 1998. He is a recipient of 1999 TxTEC Graduate Fellowship. He is currently working on his PhD research with Dr. Gustavo de Veciana. His research interest focuses on dynamic resource allocation on next generation multi-service data networks.


A list of Telecommunications and Signal Processing Seminars is available at from the ECE department Web pages under "Seminars". The Web address for the Telecommunications and Signal Processing Seminars is http://signal.ece.utexas.edu/seminars