The Evolution of the Alexandria Digital Library

James Frew
UC Santa Barbara


The Alexandria Digital Library (ADL) is one of 6 projects funded by the NSF/DARPA/NASA Digital Libraries Initiative. Since 1994, ADL Project has developed three prototype digital libraries for georeferenced information, evolving from a GIS-based system, to a simple World Wide Web interface, and finally to a a three-tier client-server architecture whose middleware layer presents a single set of interfaces to multiple heterogeneous servers. These standard interfaces, all of which are implemented in HTTP, support session management, collection discovery and evaluation, metadata searching, metadata retrieval, and online holdings retrieval. An XML-based metadata encoding scheme, a simple boolean query language, and standalone Java client have also been developed.

This talk will describe ADL's evolving architecture; demonstrate some of its past and current capabilities, and discuss the tradeoffs made and lessons learned in each successive implementation.


James Frew, ADL co-PI and development team leader, is an Assistant Professor in UCSB's Donald Bren School of Environmental Science and Management. He is interested in all aspects of Earth science information management and processing. He received his Ph.D. in Geography from UCSB in 1990. He has served as both Manager and Acting Director of UCSB's Institute for Computational Earth System Science, and as Associate Director of UC's multi-campus Sequoia 2000 Project. In addition to ADL, Frew is currently involved in NASA's prototype Earth Science Information Provider (ESIP) Federation, as both an ESIP project leader and vice-chairman of the Federation.