1. URN resolution via Z39.50 August 1999 Z39.50 Tutorial, Stockholm Juha Hakala Helsinki University Library juha.hakala@helsinki.fi

2. Contents Status of the URN initiative URN resolution via Z39.50 –aim –techniques –issues Status: early planning stage; long way to the implementations!

3. Status of the URN work Existing Internet standards: –URN syntax (RFC 2141, May 1997) –URN resolution with DNS & THTTP (RFC 2168 & RFC 2169; experimental) –URI resolution services (RFC 2483) URN to resource/URL/bib. description –URN namespace definition (RFC 2611, June 1999)

4. Status of the URN work (2) Standardization almost complete Missing pieces: –URN resolution via Z39.50 discussed within a small working group –Replacement of experimental RFC 2168 with “normal” RFC/RFCs implementation experience always required by IETF before approval

5. URN resolution via Z39.50 Aim –possibility to retrieve bibliographic data world- wide if URN is known no need to know what database contains the record - URN resolver discovery service knows this e.g. for urn:isbn:951*, connect to linko.helsinki.fi, port 2100, dbase linda Specification will be published as RFC

6. URN resolution via Z39.50 (2) Techniques –specify the description of Z3950 target info into DNS resource records –choose the method for delivering the query from the origin to the target candidate 1: Z39.50r URL

7. URN resolution - issues Technology is simple, politics is not –who will maintain the resolution services ISSN - ISSN International Centre ISBN - national bibliographies –who will pay? How to convince vendors to do it –browser developers have been reluctant; ILS vendors may react in the same way