Transcript sm-slides - NMT Computer Science and Engineering

NMT’s Computer Science
and Engineering Education
& Research Programs
Dr. Lorie M. Liebrock
Chair, Computer Science and Engineering
Subhasish Mazumdar
Associate Professor
Ph.D., Computer Science, University of Massachusetts
Specialities
Mobile data management
Document databases
Integrating heterogeneous data
sources
Subhasish Mazumdar
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Sample Research: Mobile Data Management
Mobile devices have increasingly powerful computational
ability, but
limited computing resources, e.g., battery, storage;
possibility of disconnections in network connectivity;
Likelihood of loss and theft.
Can mobile users be empowered just like users on
desktops?
No! What if a mobile client locks server data and
disconnects (voluntarily/involuntarily)? Server resources
may become unavailable to all other clients forever!
Subhasish Mazumdar
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New solutions are needed to address integrity & security.
Our approach
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assumes a three-tier architecture: (i)server, (ii)stationary support
stations, and (iii) the mobile hosts;
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rewrites global constraints into sufficient local constraints;
allows local execution when disconnected while enforcing global
integrity constraints;
thwarts attempts to reconstruct a database from a stolen
portable device; or even from a single query;
develops the idea of a lease, i.e., a contract along with the cached
data;
illuminates the interaction between lease durations and user
authority levels;
shows that changing range constraints on data in mobile hosts is
useful for security.