ColloquiaTalk by Laura Bright on Friday, Feb. 28

[Margery Ishmael]

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DEPARTMENT OF COMPUTER SCIENCE - TALK

Friday, February 28, 2003 at 2:30 pm in Ryerson 251

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Speaker: Laura Bright
From: University of Maryland, College Park
http://www.cs.umd.edu/users/bright/

Title: Profile-Based Data Delivery in Wide Area and Mobile Environments

Abstract:
The growing popularity of the Internet has led to an increase
diversity of caching technologies, for example middle-tier caches and
web proxy caches. An important characteristic of data access in wide
area environments is that applications often have different
requirements for the latency and recency of data. Traditional caching
and scheduling schemes do not provide interfaces to
express these requirements, and treat all clients and applications
alike. Further, it is difficult to accurately estimate the recency of
cached objects. In this talk I present a scheme to support diverse
clients and applications on both fixed and mobile networks using
client profiles. In the first part of this talk I introduce
latency-recency profiles, a set of parameters that allow clients to
express preferences for their different applications. These profiles
are used in caching on fixed networks, e.g., a proxy cache. A cache
uses profiles to determine whether to deliver a cached object to the
client or to download a fresh object from a remote server. I present
an architecture for profiles that is both scalable and straightforward
to implement at a cache. Next, I present techniques to improve
estimates of the recency of cached objects by increasing the amount of
information servers provide to caches. This improves the
effectiveness of using latency-recency profiles by simultaneously
reducing bandwidth consumption and increasing the recency of data
delivered to clients. Finally, I describe how profiles can be used to
support diverse applications in mobile environments. I present a
framework for incorporating profile-based decision making into the
cache utilization, downloading, and scheduling decisions at a mobile
base station. Experiments with trace data and implementation results
validate the effectiveness of using profiles.

Host: John Reppy

*Refreshments to follow the talk in Ryerson 255*




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Margery Ishmael
Secretary to the Chairman, Department of Computer Science
The University of Chicago
1100 E. 58th Street, Chicago, IL. 60637-1581
tel. 773.834.8977 fax. 773.702.8487
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