1. DNER Architecture Andy Powell, Liz Lyon MLE Steering Group 4 May 2001 UKOLN, University of Bath a.powell@ukoln.ac.uk www.ukoln.ac.uk UKOLN is funded by Resource: The Council for Museums, Archives and Libraries, the Joint Information Systems Committee (JISC) of the Higher and Further Education Funding Councils, as well as by project funding from the JISC and the European Union. UKOLN also receives support from the University of Bath where it is based.

2. MLESG - 4 May 2001 2 Contents scope of the DNER content functionality network systems architecture discovery access integration of DNER into VLEs

3. Scope What is the DNER?

4. MLESG - 4 May 2001 4 Primary Content Secondary Content Funded Institutional External Web pages Museums home pages theses research papers OPACs Institutional gateways Google Yahoo Northern Light RDN A&I images Full-text statistics Map data COPAC Amazon Public libraries courseware DNER scope by content?

5. MLESG - 4 May 2001 5 But... … not a user view … not an institutional view user view based on personalised landscape... own information foremost institutional (intranet or VLE) DNER and external (general Web stuff) probably with discipline or subject focus

6. MLESG - 4 May 2001 6 DNER Collections content typically in the form of ‘collections’ where collection is one or more items collections of stuff (text, images, data,...) collections of metadata about stuff (e.g subject gateway’s, library catalogues) local collections, ‘JISC’ collections, other collections network services make digital collections available at digital ‘locations’ real services make physical collections available at physical ‘locations’ people access content through services

7. MLESG - 4 May 2001 7 Primary DNER entities Content Person Service Host, port, protocol, schema Collection, item, discovery, description, rights, terms & conditions Contact details, preferences, subject interests, educational level

8. MLESG - 4 May 2001 8 DNER scope by function simple underlying functional model discover, access, use characterised in the solution to two problems ‘portal problem’ - how to provide seamless discovery across multiple content providers ‘appropriate-copy problem’ - how to provide access to the most appropriate copy of a resource (given access rights, preferences, cost, speed of delivery, etc.) generic - applicable to finding Web resources, buying books, buying cars,...

9. MLESG - 4 May 2001 9 Functional model iterative process move from user-need to resource on desktop (physical or digital) three stage ‘discovery process’ ‘buildLandscape’ and ‘survey’ - collection level ‘discover’ and ‘detail’ - item level ‘detail’ phase provides information about how to request instance of resource ‘detail’ may involve resolving identifier or metadata for resource using ‘resolver’ survey discover authenticate buildLandscape detail request authorise access useResource useRecord

10. MLESG - 4 May 2001 10 DNER information flow process is iterative at all stages DNER not just a ‘provider to user’ flow users are both recipients and creators of primary content, secondary content and metadata DNER architecture needs to support collaboration and creation …as well as discovery, etc. current work on architecture doesn’t really address this.

11. MLESG - 4 May 2001 11 DNER scope summary... DNER is an information environment (a set of services) that enables people to discover, access and use a wide variety of resources ‘resources’ are… services / content local / remote primary / secondary, data / metadata digital / physical JISC funded / not JISC funded policy controlled / non-policy controlled ‘discover, access and use’ includes discover / locate / access use / reuse / create receive / provide / collaborate

12. Network Systems Architecture How does the DNER do it?

13. MLESG - 4 May 2001 13 Web Content (local and remote) End-user Current services offer mix of discover, access and use functionality End-user needs to join services together manually - as well as learning multiple user interfaces Current DNER architecture

14. MLESG - 4 May 2001 14 Web Current shared services Content End-user Authentication Authorisation Authentication and authorisation already provided as shared services through Athens

15. MLESG - 4 May 2001 15 Joining things together DNER architecture provides framework for shared services machine to machine interfaces DNER as coherent whole rather than lots of stand-alone services two areas in particular... discovery finding stuff across multiple content providers access streamlining access to appropriate copy

16. Discover How does the DNER support content discovery?

17. MLESG - 4 May 2001 17 Discover want to allow end-user to discover across several network services... to support this, services need to expose content for machine to machine (m2m) use expose metadata about their content for searching harvesting alerting develop services that bring stuff together portals

18. MLESG - 4 May 2001 18 Portals portals provide access to multiple network services there will be many kinds of portals... subject portals data centre portals institutional portals personal portals (agents) virtual learning environments thin portals (shallow linking) thick portals (deep linking, richer discovery and use functionality)

19. MLESG - 4 May 2001 19 Web Thin portal Content End-user Portal Authentication Authorisation Collect’n Desc Service Desc HTTP

20. MLESG - 4 May 2001 20 Web Searching Content End-user Portal Z39.50 Bath Profile Authentication Authorisation Collect’n Desc Service Desc HTTP

21. MLESG - 4 May 2001 21 Z39.50 - Bath Profile search and retrieve support portal and broker cross-searching Bath Profile based on existing profiles cross-domain focus (in part) DC XML records DTD-based rather than XML Schema

22. MLESG - 4 May 2001 22 Web Sharing Content End-user Portal Open Archives Initiative Authentication Authorisation Collect’n Desc Service Desc HTTP

23. MLESG - 4 May 2001 23 Open Archives Initiative OAI Metadata Harvesting Framework simple mechanism for sharing metadata records records shared over HTTP...... as XML (using XML Schema) client can ask metadata server for all records all records modified in last ‘n’ days info about sets, formats, etc. See

24. MLESG - 4 May 2001 24 Web Alerting Content End-user Portal RSS Email Authentication Authorisation Collect’n Desc Service Desc HTTP

25. MLESG - 4 May 2001 25 RSS RDF Site Summary RDF/XML application for syndicated news feeds (RSS 1.0) pointers and simple descriptions of news items (not the items themselves) makes use of DC elements previous versions based on XML (RSS 0.9) no querying - just regular ‘gathering’ of RSS file http://www.ukoln.ac.uk/metadata/rssxpress/

26. Access How does the DNER help us access content?

27. MLESG - 4 May 2001 27 Resource identification discovery phase results in metadata about a resource metadata will include its identifier or a locator for Web resources a URL is common identifier/locator needs to be persistent enable lecturers to embed it into learning resources enable students to embed it into multimedia essays enable people to cite it

28. MLESG - 4 May 2001 28 Identifiers/locators also need to think about what is identified...? the resource (e.g. an image) the resource in context (e.g. image embedded into Web page) metadata about the resource (e.g. description of image) probably need to identify all of these need guidelines on good practice for use of URLs investigate use of DOIs

29. MLESG - 4 May 2001 29 Resolving identifiers may need to resolve the metadata, identifier or locator into information about how to request a particular instance of the resource this is done using resolvers resolvers find appropriate copy location is context sensitive - need to know who end-user is, where they are and what they have access to may be best carried out locally to end- user?

30. MLESG - 4 May 2001 30 OpenURL metadata, identifier or locator forms a ‘citation’ for the resource OpenURL - way to encode citation for a resource OpenURL = BaseURL + Description BaseURL provides location of a ‘resolver’ Description is either a global identifier (e.g. a DOI or ISBN) or a description (a citation) or mixture http://sfx.bath.ac.uk/sfxmenu?genre=book &isbn=1234-5678

31. MLESG - 4 May 2001 31 OpenURL resolver Content End-user Delivery service Authentication Authorisation Collect’n Desc Service Desc Resolver Portal OpenURL HTTP Inst’n Profile

32. Summary

33. MLESG - 4 May 2001 33 Web Content End-user Portal Broker/Aggregator Authentication Authorisation Collect’n Desc Service Desc Resolver Shared service model Inst’n Profile

34. MLESG - 4 May 2001 34 shared services portals content brokers and aggregators DNER architecture provision fusion infrastructure presentation m2m interfaces

35. The VLE problem? How is the DNER integrated with VLEs?

36. MLESG - 4 May 2001 36 3 points of contact DNER as a repository of ‘learning resources’ DNER as source of building blocks for learning resource creation DNER as source of trusted information for student centred activities Issues...

37. MLESG - 4 May 2001 37 DNER as repository some DNER resources will be learning resources IMS packages, Blackboard cartridges, etc. described using IMS metadata (or similar) discovery by lecturers for plugging into their VLE IMS doesn’t provide ‘standard’ way for VLE to talk to a collection of learning resources (repository) …but IMS Digital Repositories working group about to address this area

38. MLESG - 4 May 2001 38 DNER as source DNER is trusted source of building blocks for learning resources tools for packaging learning resources (IMS package constructors?) need to integrate with with DNER portals or become DNER portals portal search results need to be able to populate course reading lists

39. MLESG - 4 May 2001 39 DNER as resource VLEs provide environment for student centred activities DNER provides trusted source of rich information for such activities need to integrate VLEs closely with DNER portals or make VLEs into DNER portals

40. MLESG - 4 May 2001 40 Issues - VLEs as portals VLEs are already thin portals - provide links to external services do we expect VLE software to become think portals - i.e. to support Z39.50, OAI, RSS, etc? not necessarily… use frames to integrate external portals into VLE use CGI-based technologies such as RDN- Include not close integration… but a start

41. MLESG - 4 May 2001 41 Issues - metadata learning packages typically described using IMS (rich metadata) DNER discovery based largely on Dublin Core (simple metadata) a proposal… DC (or DC-Education) sufficient for discovery of packages IMS required within packages for integration into VLE so… IMS internal to the package but only need to expose DC (or DC-Education) externally

42. MLESG - 4 May 2001 42 Issues - common sense need shared understanding and metadata practice across whole range of services need to agree ‘cataloguing guidelines’ and terminology in 4 key areas subject classification audience level (who is this resource aimed at?) resource type (what kind of resource is this?) certification (who has created this resource?)

43. MLESG - 4 May 2001 43 Thin portals Web Content providers Web browser Portal Authentication Authorisation Collection Desc

44. MLESG - 4 May 2001 44 Searching Web Content providers Web browser Portal Authentication Authorisation Collection Desc Service Desc