@article{18c7cbadc0d5465bad3041f6733c0239,
title = "A non-equilibrium analysis and control framework for active queue management",
abstract = "We present a non-equilibrium analysis and control approach for the Active Queue Management (AQM) problem in communication networks. Using simplified fluid models, we carry out a bifurcation study of the complex dynamic queue behavior to show that non-equilibrium methods are essential for analysis and optimization in the AQM problem. We investigate an ergodic theoretic framework for stochastic modeling of the non-equilibrium behavior in deterministic models and use it to identify parameters of a fluid model from packet level simulations. For computational tractability, we use set-oriented numerical methods to construct finite-dimensional Markov models, including control Markov chains and hidden Markov models. Subsequently, we develop and analyze an example AQM algorithm using a Markov Decision Process (MDP) based control framework. The control scheme developed is optimal with respect to a reward function, defined over the queue size and aggregate flow rate. We implement and simulate our illustrative AQM algorithm in the ns-2 network simulator. The results obtained confirm the theoretical analysis and exhibit promising performance when compared with well-known alternative schemes under persistent non-equilibrium queue behavior.",
keywords = "Active Queue Management, Communication networks, Markov decision processes, Nonlinear systems",
author = "Tansu Alpcan and Paul Wang and Mehta, {Prashant G.} and Tamer Ba{\c s}ar",
note = "Funding Information: The authors would like to thank Uday Shanbhag and Umesh Vaidya for helpful discussions. Tansu Alpcan received the B.S. degree in electrical engineering from Bogazici University, Istanbul, Turkey in 1998. He received the M.S. and Ph.D. degrees in electrical and computer engineering from University of Illinois at Urbana-Champaign (UIUC) in 2001 and 2006, respectively. His research interests include network security, game theory, control and optimization of wired and wireless communication networks, resource allocation, and intrusion detection. He has received Fulbright scholarship in 1999 and best student paper award in IEEE Conference on Control Applications in 2003. He is the (co-)author of more than 40 journal and conference articles. Dr. Alpcan was an associate editor for IEEE Conference on Control Applications (CCA) in 2005 and has been TPC member of several conferences including IEEE Infocom 2007, 2008. He has been the co-chair of the workshop on Game Theory in Communication Networks (GameComm) in 2008. He has received Robert T. Chien Research Award from the UIUC Department of Electrical and Computer Engineering and Ross J. Martin Research Award from the UIUC College of Engineering in 2006. Tansu Alpcan has been a member of IEEE since 1998. He is currently a senior research scientist in Deutsche Telekom Laboratories, which is affiliated with Technische Universitat Berlin, Germany. Paul Wang is currently working at IBM Corporation. He completed his Masters of Science and Bachelors of Science at the University of Illinois at Urbana-Champaign in 2007. His research interested involved non-equilibrium queue management. During his time at UIUC, he was the President of the Pi Tau Sigma Mechanical Engineering Honorary Society. He was also the recipient of the Lisle Abbott Rose Award (2007) from UIUC College of Engineering and the Pi Tau Sigma Sophomore Award (2005) from UIUC Department of Mechanical Science and Engineering. Prashant G. Mehta is an Assistant Professor at the Department of Mechanical Science & Engineering, University of Illinois at Urbana-Champaign. He received his Ph.D. in Applied Mathematics from Cornell University in 2004. Prior to joining UIUC, he was a research engineer at the United Technologies Research Center (UTRC). At UTRC, he was recognized with an outstanding achievement award for his contributions in developing dynamical systems methods to obtain practical solutions to problems in aero-engines. His research interests are in applications of ergodic theoretic methods to control theory. Tamer Ba{\c s}ar received B.S.E.E. from Robert College, Istanbul, and M.S., M.Phil., and Ph.D. from Yale University. After stints at Harvard University and Marmara Research Institute (Gebze, Turkey), he joined the University of Illinois at Urbana-Champaign in 1981, where he is currently Swanlund Endowed Chair in the Department of Electrical and Computer Engineering, Center for Advanced Study Professor, and Research Professor in the Coordinated Science Laboratory and the Information Trust Institute. He has published extensively in systems, control, communications, and dynamic games, and has current research interests in modeling and control of communication networks, control over heterogeneous networks, resource management and pricing in networks, and security and trust in computer systems. Dr. Basar is currently the Editor-in-Chief of Automatica, Editor of the Birkhauser Series on Systems & Control, Managing Editor of the Annals of the International Society of Dynamic Games (ISDG), President-Elect of the American Automatic Control Council, and member of editorial and advisory boards of several international journals. He has received several awards and recognitions over the years, among which are the Medal of Science of Turkey (1993), Distinguished Member Award (1993), Axelby Outstanding Paper Award (1995) and Bode Lecture Prize (2004) of the IEEE Control Systems Society (CSS), Millennium Medal of IEEE (2000); Tau Beta Pi Drucker Eminent Faculty Award of UIUC (2004); the Outstanding Service Award (2005) and the Giorgio Quazza Medal (2005) of IFAC, Richard Bellman Control Heritage Award (2006) of the American Automatic Control Council, and Doctor Honoris Causa from Dogus University, Istanbul (2007). He is a member of the National Academy of Engineering, a member of the European Academy of Sciences, a Fellow of IEEE, a Fellow of IFAC, a past president of CSS, and a past (founding) president of ISDG. ",
year = "2008",
month = oct,
doi = "10.1016/j.automatica.2008.02.008",
language = "English (US)",
volume = "44",
pages = "2474--2486",
journal = "Automatica",
issn = "0005-1098",
publisher = "Elsevier Ltd",
number = "10",
}