Two Systems to (fundamentally) Restructure Wide-area Wireless Services

April 16, 2007
Time: 11:00am-12:00pm
Speaker: Rajiv Chakravorty, Cambridge University


This talk will introduce MoB and MobiStream, two systems that can change the current model of wide-area wireless services.

The first system called Mobile Bazaar, or MoB, enables collaborative wide-area wireless services. MoB changes the current model of wide-area wireless services in the following fundamental ways: (1) it decouples infrastructure providers from services providers and enables fine-grained competition, (2) it allows service interactions on arbitrary timescales, and, (3) it promotes flexible composition of these fine-grained service interactions based on user and application needs. I will first present the MoB architecture, and then describe the various MoB enablers like the user reputation management and financial incentive management, followed by an evaluation of three applications: peer-to-peer file transfers, collaborative web browsing and location-enhanced services.

The second system, MobiStream, is a video streaming system that exploits the 'perceptual' value in the video content and the characteristics of the link layer and physical layer channels to enable error-resilient video streaming. I will present the design and implementation of Mobistream, and demonstrate how the two novel concepts of "Virtual Channels" and "Perceptual Slice-structured Video" can help overcome the challenges in streaming video over (fundamentally) voice-optimized wide-area wireless channels.

The talk will include experimental results from implementation and experiments over two different commercial cellular networks.

Speaker Biography

Rajiv Chakravorty has been a Sun Microsystems Fellow and a Hughes Hall Scholar in the University of Cambridge Computer Lab. His research interests are in networks and systems, with a focus on mobile systems and wireless networking. He has worked with Philips Research, HQ the Netherlands. At IIT Delhi, he was a recipient of the DAAD Fellowship Award from Germany.

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