Conference Paper

Synchronization of TCP Flows in Networks with Small DropTail Buffers

Electrical and Computer Engineering Department, University of Massachusetts, Amherst, MA 01003, USA.
DOI: 10.1109/CDC.2005.1583249 Conference: Decision and Control, 2005 and 2005 European Control Conference. CDC-ECC '05. 44th IEEE Conference on
Source: IEEE Xplore

ABSTRACT A recent fluid-model formulation of an Internet congestion-control problem considers routers with small Droptail buffers. This paper is interested in the oscillatory regime of such networks and considers a topology where two TCP-controlled flows (each regulated by separate (edge) routers) merge to compete for bandwidth at a common (core) router. We describe this dynamic using a weakly-coupled oscillator model and analyze the coherence of oscillation as a function of coupling strength. We show that increased coupling leads to increased coherence and to larger variations in the arrival flow at the core router. The coupling strength can be expressed in terms of network parameters.

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