DATE: Thursday, November 20, 2008
TIME: 12:00 pm - 1:00 pm

Ramakrishna Gummadi
Massachusetts Institute of Technology (MIT)

Interference rendered significantly harmless

The throughput of existing wireless networks is often limited by interference. One fundamental reason is that the current designs are constrained by a "one-transmission-at-a-time" model at the link layer and a fixed-width spectrum allocation at the physical layer. We present a new wireless design that exploits traffic burstiness and node heterogeneity, thereby improving concurrency and spectrum usage. The main challenge is the unmanaged nature of many wireless networks such as 802.11 and mesh, which makes centralized resource allocation impractical. We show through analysis and implementation that simple randomized allocation policies can overcome this challenge, and improve throughput by 2x or more.

This work is joint with Rabin Patra, Hari Balakrishnan and Eric Brewer.

Ramakrishna Gummadi is a post-doc at the MIT Computer Science and Artificial Intelligence Laboratoray (CSAIL). He obtained his B.Tech. from IIT-Madras, M.S. from UC Berkeley and Ph.D. from USC, all in Computer Science. His dissertation was about reliable and efficient programming languages for sensor networks. He is interested in building scalable and reliable systems and networks based on sound principles.

His awards include a UC Regents Graduate Fellowship, a best paper awarded out of all 2001 Journal of Computer Networks papers, a best poster/demo award at SenSys 2004, and an award at the ACM Student Research Competition
(SRC) held at PLDI 2007.

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