Distributed Service Registries Workshop, July 2005 Slide 1 NISO Metasearch Initiative Registries Robert Sanderson Dept. of Computer Science University of Liverpool (With thanks to Pete Johnston )

Distributed Service Registries Workshop, July 2005 Slide 2 Overview NISO MI History Purpose and Scope Conceptual Model Collection Descriptions Service Descriptions Registries

Distributed Service Registries Workshop, July 2005 Slide 3 NISO Metasearch Initiative History First meeting May 7-8, 2003 in Denver, CO Initiated by the Content Providers, not the Metasearchers or NISO Worried about how to handle the load generated by overly broad metasearch strategies Ebsco, Thomson Gale, Elsevier Also present: Library Systems Vendors, Metasearchers, NISO

Distributed Service Registries Workshop, July 2005 Slide 4 NISO Metasearch Initiative History Initial Meeting topics: Access Management Usage Statistics Searching Options Metasearcher Identification Resource Description Result Set Management

Distributed Service Registries Workshop, July 2005 Slide 5 NISO Metasearch Initiative History Jenny Walker (Ex Libris) and Andrew Pace (NCSU) Three task groups set up TG1: Access Management (Mike Teets, OCLC) TG2: Collection and Service Description (Juha Hakala, Helsinki University/FinlandNational Library) TG3: Search and Retrieval (Matt Goldner, OCLC; Sara Randall, Endeavor)

Distributed Service Registries Workshop, July 2005 Slide 6 NISO Metasearch Initiative History Metasearch Workshop, Washington DC, October 2003 MI Face to face meeting, Raleigh-Durham, April 2004 MI Face to face meeting, Raleigh-Durham, April 2005 Plus, of course, list discussions And frequent conference calls

Distributed Service Registries Workshop, July 2005 Slide 7 Purpose and Scope Focus on Task Group 2, Collection and Service Descriptions. Purpose: To enable the discovery of appropriate, remotely maintained content and a means of retrieving that content. Discover collections of potential interest Identify a collection Select one or more collections from those discovered Identify services that provide access to the collection Select a service with with to interact Interact with service

Distributed Service Registries Workshop, July 2005 Slide 8 Purpose and Scope Scope: While the Initiative concerns metasearch, the scope of interest for TG2 is actually enabling retrieval of items. Need descriptions of collections and of services that provide access to them Electronic services only, not physical services Content services only, not transactional services Collections and services, not agents

Distributed Service Registries Workshop, July 2005 Slide 9 Conceptual Model Collections: contain one or more Items contain zero or more Collections are made available by zero or more Services Services: make available exactly one Collection

Distributed Service Registries Workshop, July 2005 Slide 10 Conceptual Model Conceptual Model Diagram: For those of you who like UML

Distributed Service Registries Workshop, July 2005 Slide 11 Conceptual Model Example: Collection Service is-available-at has-part

Distributed Service Registries Workshop, July 2005 Slide 12 Collection Descriptions Description schema builds on Dublin Core Collection Description Application Profile (DC CD AP) Provides a core set of collection description properties, not a completely comprehensive one Suitable for collection discovery across a broad range, rather than item discovery NISO MI primarily addressing 'library' style collections, with some additional requirements (strength/completeness)

Distributed Service Registries Workshop, July 2005 Slide 13 Collection Descriptions Interesting recent scoping questions: Are both a collection description of a library's collection (physical books) and a collection description of the metadata about those books (electronic records) required? (is-described-by field) Should an electronic full text collection be described in a different document to a collection summarising the items? Abstracting and Indexing services' collections?

Distributed Service Registries Workshop, July 2005 Slide 14 Service Descriptions Description schema: ZeeRex Z39.50's Explain Explained, and Re-Engineered in XML [Search and] Retrieval Services, not any Service Semantics of service, not syntax Eg: record schemas, access points, server capabilities Vs: WSDL, UDDI, ASN.1/BER, XML Schema, SOAP Need implementation of protocol before you can interact with a service via that protocol – don't need syntax stored in registry, just the semantics.

Distributed Service Registries Workshop, July 2005 Slide 15 Service Descriptions Purpose is to enable discovery and usage of appropriate services Thus needs to include 'WSDL' like fields such as host, port, path/database name Has general information to allow the record to be useful without the associated collection description (title, description etc) Also has metadata fields for harvesting source, last update Z39.50 and SRW/U oriented, but capable of describing all the protocols and retrieval methods identified by TG2

Distributed Service Registries Workshop, July 2005 Slide 16 Registries Finally, you say, he gets to the Registries bit... Actually, the MI doesn't consider a registry implementation in scope, just recommended best practice documents, especially as many of the members of the working groups are from commercial organisations with their own internal requirements and confidential data. However discussions to ensure that the documents meet the requirements have gone on... (and on, and on, and on at times)

Distributed Service Registries Workshop, July 2005 Slide 17 Some Registry Requirements Search fields in Collection Description Search fields in Service Description Cross search of Service and Collection attributes (collection about fish that has a service with a title access point) Interaction via standard protocols for search/retrieve (SRW/U, Z39.50) Harvestable (OAI-PMH) Discovery strategy for new services

Distributed Service Registries Workshop, July 2005 Slide 18 Main References NISO MI: DC CD: ZeeRex: