by Maria Bruna Baldacci and Oreste Signore
ARCA - Access to Remote CAtalogs - is a two-year project of the CEU Libraries Programme now under way at IEI and CNUCE, CNR, Pisa. ARCA aims at implementing Search/Retrieval (SR) protocol functions using a software tool of general application. The industrial partners are Intecs Sistemi S.p.a. (Italy) and Sabini (Spain).
Telematic networks (in particular, what has become known as the Internet) are now providing new ways to search bibliographic information in On-line Public Access Catalogs (OPACs) and for inter-library communication. However, there is wide diversity in the library management software used by the different OPAC systems. These differences, which occur when using telnet connections and regard both access and search modalities, cause serious difficulties for librarians (and to an even greater measure for the end users). This is true not only for access to remote catalogs but also when using neighbouring libraries, as for example in the case of a university and municipal system like that of Pisa, Italy.
For these reasons, much effort has recently been given to making it possible to access and manage a number of databases from a single, simple-to-use interface (WAIS over Gopher). Experience with this interface has been interesting and useful; however, it still does not satisfy all conditions for accessing library catalogs, and does not involve all libraries. The Z39.50 Protocol and its ISO-standard counterpart, SR-Search and Retrieve, allows users of one OPAC to interact with different OPAC's using the query language with which they are familiar. However libraries must work hard to make their OPACs capable of functioning as "servers" (or "targets" in protocol terms) in the SR protocol communication and this is a severe obstacle to the diffusion of the Protocol. The main objectives of the ARCA project are thus: • to implement SR Target functions using a software tool of general application that allows any existing OPAC to become, with a minimum of effort, a "target system" with respect to the SR protocol • to define and prototype an innovative library application that allows end users (e.g. librarians) to assess the SR Target implementation. This SR Target tool will be based on a description of the OPAC characteristics (e.g. access points) stored in a dictionary with a well defined structure. This dictionary will contain all the relevant data that are needed to translate the SR service requests (e.g. search) into commands that can be managed by the underlying OPAC. Depending on the structure of the existing library software, minor or major pieces of code specific to the OPAC must be written. The figure shows the software architecture proposed.
The SR Target system can be seen as consisting of the following parts: the SR Target Kernel and the Dictionary, which are OPAC-independent, and the SR Target OPAC interface, clearly OPAC-dependent. The ARCA System will be tested on two different library software systems with very different architectures. The libraries involved are:
Another objective of ARCA is to involve professional librarians and institutions of Southern Europe in the ongoing work and discussion surrounding the implementation of SR protocol services.