VIRTUAL SHELVES IN A DIGITAL LIBRARY - A FRAMEWORK FOR ACCESS TO NETWORKED INFORMATION-SOURCES

Objective: Develop a framework for collections-based access to network ed information sources that addresses the problem of location-dependen t access to information sources. Design: This framework uses a metapho r of a virtual shelf. A virtual shelf is a general-purpose server that is dedicated to a particular information subject class. The identifie r of one of these servers identifies its subject class. Location-indep endent call numbers are assigned to information sources. Call numbers are based on standard vocabulary codes. The call numbers are first map ped to the location-independent identifiers of virtual shelves. When a ccess to an information resource is required, a location directory pro vides a second mapping of these location-independent server identifier s to actual network locations. Results: The framework has been impleme nted in two different systems. One system is based on the Open System Foundation/Distributed Computing Environment and the other is based on the World Wide Web. Conclusions: This framework applies in new ways t raditional methods of library classification and cataloging. It is com patible with two traditional styles of selecting information sources, searching and browsing. Traditional methods may be combined with new p aradigms of information searching that will be able to take advantage of the special properties of digital information. Cooperation between the library-informational science community and the informatics commun ity can provide a means for a continuing application of the knowledge and techniques of library science to the new problems of networked inf ormation sources.