Departmental Papers (ESE)


We present a framework for designing end-to-end congestion control schemes in a network where each user may have a different utility function and may experience noncongestion-related losses. We first show that there exists an additive-increase-multiplicative-decrease scheme using only end-to-end measurable losses such that a socially optimal solution can be reached. We incorporate round-trip delay in this model, and show that one can generalize observations regarding TCP-type congestion avoidance to more general window flow control schemes. We then consider explicit congestion notification (ECN) as an alternate mechanism (instead of losses) for signaling congestion and show that ECN marking levels can be designed to nearly eliminate losses in the network by choosing the marking level independently for each node in the network. While the ECN marking level at each node may depend on the number of flows through the node, the appropriate marking level can be estimated using only aggregate flow measurements, i.e., per-flow measurements are not required.

Document Type

Journal Article

Date of this Version

October 2003


Copyright 2003 IEEE. Reprinted from IEEE/ACM Transactions on Networking, Volume 11, Issue 5, October 2003, pages 689-702.
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Explicit congestion notification (ECN) marking, Internet congestion control, TCP, TCP over wireless



Date Posted: 20 November 2004

This document has been peer reviewed.