DATE: Thursday, April 21, 2005
TIME: 12:00 pm - 1:00 pm
PLACE: Wean Hall, Room 8220

M. T. Raghunath
IBM - TJ Watson Center

SoulPad: Using USB storage to migrate personal computing state

SoulPad, uses an auto-configuring operating system along with a hibernated virtual machine on a USB disk to enable a user to suspend one's personal computing state on one PC and resume it on another PC. The USB disk essentially carries the soul of the user's PC while the host PCs provide environments where the soul can come alive. Since the operating system to boot the host PC, the VMM layer and the hibernated virtual machine state are all carried by the user on the SoulPad, host PC dependencies are significantly reduced. Host PCs may be diskless and may also lack network connectivity.

SoulPad shares many of its goals with the ISR project at CMU. Our approach however started with the "carry everything with you" model as opposed to the "carry nothing with you" model of ISR. To safeguard against loss of the storage media, we need access to the back-up servers on the network. ISR has added portable storage media to improve performance. To some extent, there is already a convergence in the approaches though they began from different starting positions. Further work in combining the two approaches may be of interest.

In this talk, I will discuss our experience in implementing the SoulPad prototype, and the issues that came up as we tested SoulPad with a variety of PC configurations. I will also discuss our measurements of resume and suspend latencies as well as operational overheads due to virtualization and USB access speeds. I will also discuss several interesting research challenges that we have uncovered as part of this research.

Joint work with: Chandra Narayanaswami, Ramon Caceres and Casey Carter (UIUC)

M. T. Raghunath is a Research Staff Member at the IBM TJ Watson Research Center. His research interests include various aspects of pervasive and mobile computing, such as the design of mobile devices, wireless interfaces, energy management, security, privacy, and design of user-interfaces for small form factor devices. He received an Outstanding Technical Achievement Award for his contributions to the Linux Wristwatch project. Dr. Raghunath received his MS and PhD in Computer Science from the University of California, Berkeley. Earlier he completed his B. Tech in Computer Science and Engineering from the Indian Institute of Technology, Madras.

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