Distributed data base access in national systems

Abstract

This paper discusses the role of alternative technologies for distributed access to data bases in national systems. It considers the complementary use of online access to centralized files (especially of high use material and recent acquisitions) and microcomputer access to local files (especially using video-disc technologies). It presents examples of current developments (at the National Library of Medicine and the Library of Congress, in the United States, for purposes of archival preservation; in the planning of several commercial data base distribution services, again in the United States; and at the Lending Division of the British Library, using the proposed commercial service called ADONIS). It discusses the ways in which the various operations in a national system can be implemented: data acquisition, maintenance, and distríbution; data search and display; data processing and output. Two contexts are given specific attention: reference data base systems and full-text systems, in each case emphasizing scientific and technical information. It considers the various trade-offs between costs and benefits in alternative configurations.