ABSTRACT |
Fabian E. Bustamante, Patrick Widener and Karsten Schwan
College of Computing
Abstract
Common to computational grids and pervasive computing is the need for
an expressive, efficient, and scalable directory service that provides
information about objects in the environment. We argue that a
directory interface that `pushes' information to clients about changes
to objects can significantly improve scalability. This paper describes
the design, implementation, and evaluation of the Proactive Directory
Service (PDS). PDS' interface supports a customizable `proactive' mode
through which clients can subscribe to be notified about changes to
their objects of interest. Clients can dynamically tune the detail and
granularity of these notifications through filter functions
instantiated at the server or at the object's owner, and by remotely
tuning the functionality of those filters. We compare PDS' performance
against off-the-shelf implementations of DNS and the Lightweight
Directory Access Protocol. Our evaluation results confirm the expected
performance advantages of this approach and demonstrate that
customized notification through filter functions can reduce bandwidth
utilization while improving the performance of both clients and
directory servers.
Georgia Institute of Technology
Atlanta, GA 30332, USA
{fabianb, pmw, schwan}@cc.gatech.edu
Last modified: Thu Sep 18 14:44:46 EDT 2003