talk

[Mohammed Nafie]

Dear All,

Prof. Emre Koksal from Ohio State University will give a seminar on Monday June 28th from 3 to 4 in the C3 lab in B72.

Abstract and Bio follows.

TITLE: Perspectives on Secure Wireless Networks and Efficient Energy Replenishing Sensor Networks

ABSTRACT: This talk is composed of two separate parts. In the first part of the talk, we will focus on a random extended network, where the legitimate and eavesdropper nodes are assumed to be placed according to Poisson point processes in a square region of area n. We show that, when the legitimate nodes have a unit intensity and the eavesdroppers have an intensity of O((log n)^-2), almost all of the nodes achieve a perfectly secure rate of O(1/sqrt(n)). The achievability argument is based on a novel multi-hop forwarding scheme where randomization is added in every hop to ensure maximal ambiguity at the eavesdropper(s). Remarkably, under these assumptions, securing the transmissions of nodes does not entail a loss in the per-node throughput in terms of scaling.

In the second part of the talk, we study sensor networks with nodes, which have rechargable energy sources. In order to achieve a perpetual network operation, the energy consumption rate at each node cannot be higher than the energy harvesting rate. Otherwise, the node will frequently deplete its battery and block critical network functions. In this talk, we consider the problem of optimal alloction of sampling rates, routing and congestion control in such networks. In contrast to traditional network resource allocation problems where the resources are static, the time-varying recharging rate presents new challenges. Fluctuations in recharging can happen at a faster time-scale than the convergence time of classical dual decomposition and subgradient based algorithms. To address this issue, we propose two algorithms, QuickFix and SnapIt, which run in parallel to achieve a performance, close to the optimal and at the same time keep the batteries at at a target level. Our evaluations show that, QuickFix and SnapIt working in tandem achieves a sampling rate, 42% higher compared to IFRC, a standard back-pressure based algorithm.


BIO: C. Emre Koksal received the B.S. degree in electrical engineering from the Middle East Technical University, Ankara, Turkey, in 1996, and the S.M. and Ph.D. degrees from the Massachusetts Institute of Technology (MIT), Cambridge, in 1998 and 2002, respectively, in electrical engineering and computer science. He was a Postdoctoral Fellow in the Networks and Mobile Systems Group in the Computer Science and Artificial Intelligence Laboratory, MIT, until 2003 and a Senior Researcher jointly in the Laboratory for Computer Communications and the Laboratory for Information Theory at EPFL, Lausanne, Switzerland, until 2006. Since then, he has been an Assistant Professor in the Electrical and Computer Engineering Department, Ohio State University, Columbus, Ohio. His general areas of interest are wireless communication, communication networks, information theory, stochastic processes, and financial economics.