Rate-based Congestion Control in Wireless Sensor Networks

Associate Professor Bhaskar Krishnamachari, Department of Electrical Engineering-Systems, Department of Computer Science, University of Southern California

Thursday, September 18, 2008
11 a.m.

CSB 209


Since the pioneering work by Kelly et al. (1998) and Low-Lapsley (1999), there has been a concerted attempt to make congestion control a science rather than an art, by giving it a mathematical basis. In wired networks, this approach has found success in developing efficient new schemes. I describe our attempt to bridge the larger gap between theory and practice in the context of rate control protocols for wireless sensor networks.

I will present the wireless rate control protocol (WRCP), the first explicit and precise distributed rate-based congestion control protocol for tree-based data gathering in wireless sensor networks. At the core of our approach is a new receiver capacity model for wireless networks that associates capacities with nodes instead of links. We show through extensive results from testbed experiments that WRCP offers substantial improvements over the state of the art in flow completion times as well as in end-to-end packet delays, while providing comparable converged rates. I will also discuss how the receiver capacity model can be used to implement rate optimization using Lagrange duality and shadow-pricing as per the Low-Lapsley framework. Finally, I will present our ongoing work on developing a novel Backpressure-based Rate Control Protocol (BRCP), which performs rate optimization based on queue-backpressure scheduling and Lyaopunov-drift minimization.

This talk is based on work with my students Avinash Sridharan and Scott Moeller.

Speaker Biography

Bhaskar Krishnamachari is an Associate Professor in the Ming Hsieh Electrical Engineering department at the USC Viterbi School of Engineering. He obtained his B.E. at The Cooper Union (1998), and both his M.S. (1999) and Ph.D. (2002) from Cornell University, all in Electrical Engineering. His research interests are in the design and performance analysis of protocols for wireless networks, particularly sensor networks. He received the NSF CAREER award in 2004, and held the Philip and Cayley MacDonald Early Career Endowed Chair at USC from 2005-2008. He has received best papers awards at IPSN 2004 and MSWiM 2006. He serves as an editor for several journals including the IEEE Transactions on Mobile Computing and the ACM Transactions on Sensor Networks and will serve as TPC Chair for DCOSS 2009 and TPC Vice Chair for IEEE SECON 2009. He is the author of a book titled Networking Wireless Sensors, published by Cambridge University Press.