8th Intl. Symposium on Modeling and Optimization in Mobile, Ad Hoc, and Wireless Networks

May 31 to June 4 at the University of Avignon, Avignon France.

Please visit http://www.wi-opt.org for more details.

The WiOpt 2010 program will feature keynote addresses by Eytan Modiano (MIT), Shlomo Shamai (Technion), and Jean Walrand (UC Berkeley)

Jean Walrand (UC Berkeley)

Jean Walrand received his Ph.D. in EECS from UC Berkeley and has been on the faculty of that department since 1982. He is the author of An Introduction to Queueing Networks (Prentice Hall, 1988) and of Communication Networks: A First Course (2nd ed. McGraw-Hill,1998) and co-author of High-Performance Communication Networks (2nd ed, Morgan Kaufman, 2000) and of Communication Networks: A Concise Introduction (Morgan & Claypool, 2010). His research interests include stochastic processes, queuing theory, communication networks, game theory and the economics of the Internet. Prof. Walrand is a Fellow of the Belgian American Education Foundation and of the IEEE and a recipient of the Lanchester Prize and of the Stephen O. Rice Prize.

Distributed Algorithms for Wireless Networks

The talk reviews recent results on scheduling, routing, and congestion control for wireless networks. We explain algorithms where a transmitter requests a radio channel with an urgency that increases with the back-pressure of the packet it tries to transmit. Such a scheme automatically adjusts the likelihood of transmissions to match the arrivals at the nodes. Combined with local admission control, such algorithms maximize the long-term utility of the flows in the network. We discuss the effect of collisions on these algorithms and extensions to anycast and multicast. (Joint work with Libin Jiang.)

Shlomo Shamai (Technion)

Shlomo Shamai (Shitz) received the B.Sc., M.Sc., and Ph.D. degrees in electrical engineering from the Technion-Israel Institute of Technology, in 1975, 1981 and 1986 respectively.

During 1975-1985 he was with the Communications Research Labs in the capacity of a Senior Research Engineer. Since 1986 he is with the Department of Electrical Engineering, Technion---Israel Institute of Technology, where he is now the William Fondiller Professor of Telecommunications. His research interests encompasses a wide spectrum of topics in information theory and statistical communications.

Dr. Shamai (Shitz) is an IEEE Fellow and a member of the Union Radio Scientifique Internationale (URSI). He is the recipient of the 1999 van der Pol Gold Medal of URSI, and a co-recipient of the 2000 IEEE Donald G. Fink Prize Paper Award, the 2003, and the 2004 joint IT/COM societies paper award, and the 2007 IEEE Information Theory Society Paper Award, and the 2009 European Commission FP7, Network of Excellence in Wireless COMmunications (NEWCOM++) Best Paper Award. He is also the recipient of 1985 Alon Grant for distinguished young scientists and the 2000 Technion Henry Taub Prize for Excellence in Research. He has served as Associate Editor for the Shannon Theory of the IEEE Transactions on Information Theory, and also has served on the Board of Governors of the Information Theory Society.

Robust Cooperation and Relaying in Wireless Networks: An Information Theoretic Perspective

In many wireless networks, cooperation, in the form of relaying, takes place over out-of-band spectral resources. Examples are ad hoc networks in which multiple radio interfaces are available for communications or cellular systems with (wireless or wired) backhaul links. We overview from an information-theoretic standpoint cooperation via out-of-band links for both ad hoc and cellular networks. Emphasis is put on robust approaches and on practical aspects such as imperfect information regarding the channel state and the codebooks (modulation, coding) shared by transmitters and receivers.

Specifically, we first focus on cooperation scenarios with perfect channel state information and investigate the impact of lack of information regarding the codebooks (oblivious processing) on basic relay channels and cellular systems with cooperation among base stations. We then turn to the analysis of similar models in the absence of perfect channel state information. Robust coding strategies are designed based on the broadcast coding approach (or unequal error protection codes). Validations of the effectiveness of such strategies are discussed for multirelay channels and cellular systems overlaid with femtocell hotspots.

Based on joint studies with E. Erkip, A. Goldsmith, D. Gunduz, H. V. Poor, A. Sanderovich, O. Simeone, O. Somekh.

Eytan Modiano (Massachusetts Institute of Technology)

Eytan Modiano received his B.S. degree in Electrical Engineering and Computer Science from the University of Connecticut at Storrs in 1986 and his M.S. and PhD degrees, both in Electrical Engineering, from the University of Maryland, College Park, MD, in 1989 and 1992 respectively. He was a Naval Research Laboratory Fellow between 1987 and 1992 and a National Research Council Post Doctoral Fellow during 1992-1993. Between 1993 and 1999 he was with MIT Lincoln Laboratory where he was the project leader for MIT Lincoln Laboratory's Next Generation Internet (NGI) project. Since 1999 he has been on the faculty at MIT; where he is an Associate Professor. His research is on communication networks and protocols with emphasis on satellite, wireless, and optical networks. He is the co-recipient of the Sigmetrics 2006 Best paper award for the paper “Maximizing Throughput in Wireless Networks via Gossiping,” and the Wiopt 2005 best student paper award for the paper “Minimum Energy Transmission Scheduling Subject to Deadline Constraints.”

He is currently an Associate Editor for IEEE/ACM Transactions on Networking. He had served as Associate Editor for IEEE Transactions on Information Theory, and as guest editor for IEEE JSAC special issue on WDM network architectures; the Computer Networks Journal special issue on Broadband Internet Access; the Journal of Communications and Networks special issue on Wireless Ad-Hoc Networks; and for IEEE Journal of Lightwave Technology special issue on Optical Networks. He was the Technical Program co-chair for IEEE Wiopt 2006, IEEE Infocom 2007, and ACM MobiHoc 2007.

Optimal Control of Wireless Networks: Past, Present, and Future Directions

This talk reviews recent advances on network control for wireless networks with stochastic traffic and time-varying channel conditions. We start with a review of the seminal work of Tassiulas and Ephremides on optimal scheduling and routing, followed by recent extensions to optimal flow control. In particular, we describe a dynamic control strategy, for joint flow control, routing, and scheduling, which maximizes the sum utility in the network. The scheduling component of this algorithm is inherently centralized and requires the solution of a complex optimization problem (i.e., finding the max-weight activation set). Hence, we discuss recent efforts toward the design of efficient distributed scheduling algorithms; including the use of distributed maximal scheduling and randomized algorithms. Finally, we describe recent results on scheduling in the presence of a mix of heavy-tailed and light-tailed traffic. In particular, we show that when some of the traffic in the network is heavy-tailed, under max-weight scheduling the expected delay is unbounded even for the light-tailed traffic. This surprising result shows that, in some sense, max-weight scheduling is delay unstable when some of the traffic is heavy-tailed. Thus, we present an adaptation of max-weight scheduling that gives bounded delays for the light-tailed traffic.