Analysis and design of controllers for AQM routers supporting TCP flows

Author

Hollot, C.V. ; Misra, Vishal ; Towsley, Donald ; Gong, Weibo

Author_Institution

Dept. of Electr. & Comput. Eng., Massachusetts Univ., Amherst, MA, USA

Volume

47

Issue

6

fYear

2002

fDate

6/1/2002 12:00:00 AM

Firstpage

945

Lastpage

959

Abstract

In active queue management (AQM), core routers signal transmission control protocol (TCP) sources with the objective of managing queue utilization and delay. It is essentially a feedback control problem. Based on a recently developed dynamic model of TCP congestion-avoidance mode, this paper does three things: 1) it relates key network parameters such as the number of TCP sessions, link capacity and round-trip time to the underlying feedback control problem; 2) it analyzes the present de facto AQM standard: random early detection (RED) and determines that REDs queue-averaging is not beneficial; and 3) it recommends alternative AQM schemes which amount to classical proportional and proportional-integral control. We illustrate our results using ns simulations and demonstrate the practical impact of proportional-integral control on managing queue utilization and delay

Keywords

computer network management; delays; feedback; queueing theory; stability; telecommunication congestion control; telecommunication network routing; transport protocols; two-term control; PI control; TCP; active queue management; computer networks; congestion-avoidance mode; delay; feedback control; network routing; parametric robustness; random early detection; stability; transmission control protocol; Computer science; Delay effects; Feedback control; Helium; Internet; Pi control; Protocols; Queueing analysis; Robust control; Robust stability;

fLanguage

English

Journal_Title

Automatic Control, IEEE Transactions on

Publisher

ieee

ISSN

0018-9286

Type

jour

DOI

10.1109/TAC.2002.1008360

Filename

1008360