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Z39.50 and the JISC Services Brian Kelly UK Web Focus UKOLN http://www.ukoln.ac.uk/ [email protected] 1 Who's Using It? Which JISC services are currently using Z39.50? Which JISC services have tested Z39.50? 2 The Problem 3 End users face difficulties due to the wide variety of search interfaces available Possible Solutions Agree to use the same software Unlikely to happen Undesirable Agree to use implement similar interfaces The Common User Interface (JISC) group gave reasons why this wasn't sensible Use software which implements protocol designed to provide common search interface across diverse services Z39.50 4 What Is Z39.50? Z39.50: • A protocol which specifies data structures and interchange rules that allow a client machine to search databases on a server machine and retrieve records that are identified as a result of the search • Maintained by Library of Congress • Developed by ZIG Why is it important? • Powerful searching • Local, familiar interface • Retrieves structured data 5 What's It Look Like? Z39.50 services can http://www.niss.ac.uk/ z3950/z3950.html be accessed using Web browsers. NISS provides access to: • HEQC Access Courses Database • CIA World Factbook 6 Full Record United Kingdom <//COUNTRY United Kingdom, Geography Location: Western Europe, bordering on the North Atlantic Ocean and the North Sea, between Ireland and France <//LOCATION Map references: Europe, Standard Time Zones of the World <//MAPREF Area: total area: 244,820 sq km land area: 241,590 sq km comparative area: slightly smaller than Oregon note: includes Rockall and Shetland Islands Land boundaries: total 360 km, Ireland 360 km <//BOUNDARIES What's It Look Like? (2) Europagate is a Multifunctional Gateway for Information Retrieval Protocols http://europagate.dtv.dk/ 7 Z39.50 Clients (1) Dedicated Z39.50 clients are available. Issues: • Which is the best client? • Costs • Additional software for computing services to support 8 Znavigator Client Z39.50 Clients (2) Z39.50 clients could be written in Java. Issues: • Client managed by server provider • Integrated with web browser • How widespread is support for Java? Contact [email protected] for details 9 Questions About Java Is Java ready for prime time? • • • • • Widespread support in existing browsers Support promised in operating systems Minimises local installation/support effort Exploit local PC processing power Potential for negotiation over processing: Server Do you do Java Client No Server OK, I'll do the processing and give you the HTML But: 10 ??? Who Benefits? End User Ease of use Productivity gains Information Service Provider More effective use of service Service "hidden" Complex (?) Z39.50 software to support Local Support Service (IT/Library) Reductions in user queries Extra client software to support Where is the pressure for Z39.50 coming from? 11 Remember WAIS? WAIS • "Inspired" by Z39.50 (1988) • Still used for searching sites • Distributed searching did not take off - why? At Leeds University: • Computing Service documents indexed using WAIS (HTML and Postscript) • WWWWAIS gateway used • WAIS server not centrally registered • Work done in early 1994 12 Institutional Acceptance Is it desirable for UK HEIs to run their own Z39.50 servers? How should searching across UK HEI's web pages be achieved: • Centralized harvest of pages • Everyone running Z39.50 servers and gateways 13 Potential For JISC Services Image a chemist who wants to find out more about CML (Chemical Markup Language) and the Jumbo CML browser find Jumbo and CML Hits from • HENSA archive of software • Mailbase archives containing discussions about the software • A chemistry information gateway 14 Implementation Issues What needs to be done to implement a Z39.50 service? • Systems issues – server models – client issues • Other issues – attribute set mapping – etc. 15 Implementation Models There are several models for running a Z39.50 service across national services WWW server Z39.50 Server Z39.50 Gateway WWW/Z39.50 Gateway Information service providers run Z39.50 and WWW gateway software WWW-Z39.50 gateways provided: (a) nationally (b) distributed (organisations/regions) Clients: • Dedicated Z39.50 clients may be used • Java Z39.50 clients may be used • Web browsers may be used 16 UKOLN Experiences Evaluating Europagate (gateway), Zebra and Isite (Z39.50 servers) with: • • • • 17 eLib project descriptions National Art Library ADAM service Ariadne See pointer to Experimental Z39.50 servers at http://www.ukoln.ac.uk/ metadata/ Alternatives To Z39.50 Do Nothing Do Like Me Centralised Database Harvest gathers Use Other Protocols LDAP Whois++ Solutions At Other Levels Application Layer CORBA / IIOP Distributed Objects (see MIDRIB) 18 What Next? What should we do next? • Agree on a model for JISC services? • Agree on a diversity of models and share experiences? • Find out what others are doing? • Find out about plans for client systems within community? Remember other technological developments we'll have to consider: 19 XML Cougar Java ActiveX Metadata PICS ... Stylesheets Authentication Further Information For further information on Z39.50 see: • UKOLN's list of resources at http://www.ukoln.ac.uk/z3950/ • Z39.50 Client Survey at http://www.dstc.edu.au/RDU/ reports/zreviews/z3950-clientsurvey.html 20 • DLIB article The Z39.50 Information Retrieval Standard: Part I: A Strategic View of Its Past, Present and Future at http://hosted.ukoln.ac.uk/mirrored /lis-journals/dlib/dlib/dlib/ april97/04contents.html