My research interests are in the area of
computer systems modeling and performance evaluation.
One aspect of my research
has been development of
models and efficient methodologies
for evaluation of systems at design time.
High level abstractions that allow for
evaluation of design choices (rather than
prediction of performance numbers of the final product) can
provide insight into the system being designed, expose the tradeoffs involved,
and lead to significantly better designs of systems.
In general, design choices are better
studied through analytical
models --- at design time it is desirable to obtain results quickly
since there is a large number of possible design choices.
which may be obtained through detailed simulations or measurements
is often not needed at design time or simply not possible or economical
Hence, I work on analytical performance evaluation methodologies that
lead to (a) reasonably simple abstractions,
needed for ease of applicability,
and (b) efficient solution techniques, needed for
rapid evaluation of design ideas.
Another aspect of my research has been
quality-of-service-based design of
large-scale continuous media storage systems and their
subsequent performance evaluation.
Many systems today
are moving towards applications whose primary function is to
transfer large volumes of data
from an I/O subsystem through the network, possibly subject to some form of
Therefore, efficient storage system designs
are fundamental to the viability of these applications,
and I expect our work to be of use to
a broad range of current and future systems
More recently, I have focused on performance aspects of
scalable upload applications over
To the best of our knowledge there is no existing work,
except ours, on making upload applications
scalable and efficient.
This corresponds to an important class of applications,
which includes digital government, digital democracy, and
My current work in this area is on design of an application layer
infrastructure that will improve scalability and security
of current and future Internet-based services.