Modeling the interdependency of low-priority congestion control and active queue management

TL;DR

This paper investigates the negative interactions between low-priority congestion control protocols and active queue management, proposing a fluid model and a system-level solution to restore protocol priorities.

Contribution

It introduces a fluid model to analyze the dynamics of heterogeneous congestion controls under AQM and proposes a solution to maintain protocol priorities.

Findings

Negative interplay identified between AQM and low-priority protocols

Fluid model accurately describes system dynamics

Proposed solution successfully reinstates protocol priorities

Abstract

Recently, a negative interplay has been shown to arise when scheduling/AQM techniques and low-priority congestion control protocols are used together: namely, AQM resets the relative level of priority among congestion control protocols. This work explores this issue by (i) studying a fluid model that describes system dynamics of heterogeneous congestion control protocols competing on a bottleneck link governed by AQM and (ii) proposing a system level solution able to reinstate priorities among protocols.