1. Service Registries In a Digital Library World

2. Sponsors / Support NSF / NSDL DUE #0612874 DLF JISC UKOLN

3. Outline Context Definition Current State Opportunity More context

4. Context Increasing prevalence of digital library services Trend towards Service Oriented Architectures (SOA) for Digital Libraries Need for Just-In-Time (JIT) Service Coordination

5. Why SOA? Scholarly Communication Workflows –Diverse –Customizable –Adjustable Ever changing DL landscape –New collections constantly being made available –New collections = new services Multiple services per collection

6. JISC IE

7. Service Oriented Approach Many different types of services and service interfaces / protocols Early recognition of the need of a service registry

8. How to Scale in a SOA? Need to know what services exist Need to know how to get to those services Need to know how to connect to those services Discover, Locate, Interface

9. (Some) Requirements SOA requires m2m capability Different functional needs require different data, potentially different interfaces Discover, Locate, and Interface needs have to be addressed in ways that enable the m2m capability

10. Definition A Digital Library Service Registry provides the ability to discover, locate, and interface with a registered service.

11. Definition Some registries might do more –Less? The core needs must always be met –Service Choreography (Powell) –Just-in-time Service Coordiation

12. Use Case Examples Search / Metasearch Resource Validation Preservation Name Authority

13. Current State Ontologies –Ex. JISC/IESR Metadata Model Some thoughts –Definition of Service Vocabulary –Approach: Minimal or Comprehensive?

14. Current Interfaces OAI-PMH Z39.50 SRU/W OpenURL Web-page What interfaces make sense? One interface fits all, or different interfaces (metadata?) for distinct functional needs?

15. Opportunity / Issues Are Discover, Locate, and Interface the core functions / needs? What sort of descriptive information is needed to meet each core need? What specific interfaces / protocols are needed for each core need? How do many registries work in conjunction? –Many registry efforts, lots of current value –Centralized, peer-to-peer, distributed, mixed