[Colloq] Hiring Talk, Wednesday, April 18, 11:40am

[Rachel Kalweit]

College of Computer and Information Science Colloquium

Presents a Hiring Talk By:
Ben Liang
The University of Toronto

Who will speak on:
Distributed Persistent Data Storage in Wireless Sensor Networks

Wednesday, April 18, 2007
11:40 am
366 West Village H
Northeastern University

Abstract:
Wireless sensor networks consist of unreliable and energy constrained 
sensors operating in an unstable communication environment. When these 
networks are scaled up to thousands or hundreds of thousands of nodes, 
it is generally inefficient or infeasible to deploy powered sinks or 
fixed gateways to collect data and forward them to the outside world. In 
this talk, we discuss how distributed coding techniques can be employed 
to provide fault-tolerant data storage in a large-scale wireless sensor 
network where the sensors collectively store the measured data. 
Attracted by the coding performance and decoding efficiency of fountain 
codes with a large data set, we propose two decentralized 
implementations of fountain codes over multiple sensors. Both 
implementations are based on
network-wide random walks. The first implementation, termed Exact 
Decentralized Fountain Codes, provides the same level of fault tolerance 
as the original centralized fountain codes. The second implementation, 
termed Approximate Decentralized Fountain Codes, trades off fault 
tolerance for lower data dissemination cost. We discuss the design 
choices and performance analysis of these implementations. We show that, 
asymptotically and in actual experiments, both implementations are able 
to provide near-optimal fault tolerance with minimum storage requirement 
in each sensor.

Biography:
Ben Liang received honors simultaneous B.Sc. (valedictorian) and M.Sc. 
degrees in electrical engineering from Polytechnic University in 
Brooklyn, New York, in 1997 and the Ph.D. degree in electrical 
engineering with computer science minor from Cornell University in 
Ithaca, New York, in 2001. In the 2001 - 2002 academic year, he was a 
visiting lecturer and post-doctoral research associate at Cornell 
University. He joined the Department of Electrical and Computer 
Engineering at the University of Toronto as an Assistant Professor in 
2002. His current research interests are in mobile networking and 
multimedia systems. He received an Intel Foundation Graduate Fellowship 
in 2000 toward the completion of his Ph.D. dissertation, the Best Paper 
Award at the IFIP Networking conference in 2005, and the Runner-up Best 
Paper Award at the International Conference on Quality of Service in 
Heterogeneous Wired/Wireless Networks in 2006. He has served as 
Technical Vice Co-chair for IEEE MASS 2006, General Co-chair for 
Ambi-sys 2008, and a technical program member of several major 
conferences including IEEE INFOCM, ACM MobiCom, IFIP Networking, IEEE 
Globecom, IEEE ICC, and IEEE LCN. He is a senior member of IEEE and a 
member of ACM and Tau Beta Pi.

Host: Guevara Noubir

-- 
Rachel Kalweit
College of Computer and Information Science
202 West Village H
Northeastern University
phone: 617-373-2462
fax: 617-373-5121
rachelb at ccs.neu.edu