David Massart < david.massart@eun > Tel Aviv University - Jan. 16, 2005.

1. David Massart <david.massart@eun.org> Tel Aviv University - Jan. 16, 2005.

2. Outline • Context, motivations, and requirements • The SQI Application Programming Interface • Usage scenarios • Current status • Bindings and Application Profiles • Who is using it ? • The Celebrate Gateway • The iClass Adapter

3. Query Service Interoperability In order to be able to query each others, repositories must agree on: • A Query Language • A Result Format • A Query Interface

4. SQI is an Application Program Interface (API) • An API for querying learning objects repositories • Since one major design objective is to keep the specification simple and easy to implement, the interface is labelled Simple Query Interface (SQI)

5. Who Is Behind It ? • API Specification: • CEN/ISSS Learning Technology Workshop • E. Duval, D. Massart, B. Simon, S. Ternier, F. Van Assche, M. Arnaud • Implementations: • WP3 ProLearn network of Excellence (FP6) • Ariadne, Celebrate, Edutella, Elena, ...

6. Motivations Small-step approach: • Connecting as many European LO repositories (metadata search) as possible • Proving that it works • Creating the need for better interoperability

7. Requirements Combining highly heterogeneous repositories requires to: • Be neutral in terms of results format and query languages • Support Synchronous and Asynchronous Queries in order to allow heterogeneous networks to connect to each other

8. Result Schema Neutrality ? • Any schema that two or more repositories have agreed on is valid • An SQI schema serves two purposes: • It identifies the set of attributes and vocabularies that can be used in the query • It provides a format in which learning object descriptions are returned • For example, both XML schemas and RDF schemas are valid

9. Query Language Neutrality • Query languages • are not neutral • Any query language chosen (e.g. XQUERY) would have a negative impact on the adoption of the interface by those repository types the language has not been designed for (e.g. RDF repositories in the case of XQUERY).

10. Why Neutrality ? SQI • Does not contribute to overcome the differences of the various paradigms in metadata management (Z39.50, XML-based approaches, RDF community) • Aims at becoming an independent specification for all open educational repositories

11. Federation Host 3 SQI Gateway Federation Host 2 SQI Federation Host 1 Why Asynchronous ?

12. Federation Host 3 SQI Gateway Federation Host 2 SQI Federation Host 1 Why Asynchronous ?

13. Asynchronicity • Simple • Robust • Scales up well • Enables Selective Dissemination of Information (SDI)

14. What is SQI good for ? • Metadata search of LO repositories • Any search (metadata, full text, ...) • Any “function” (e.g., in the iClass project, SQI is also used to obtain LOs)

15. The SQI Application Program Interface

16. Asynchronous Query Interface • asynchronousQuery • setSourceLocation • queryResultsListener • Session Management • createSession • createAnonymousSession • destroySession SQI Methods • Query Configuration • setQueryLanguage • setResultsFormat • setMaxQueryResults • setMaxDuration • Synchronous Query Interface • setResultsSetSize • synchronousQuery • getTotalResultsCount • getAdditionalQueryResults

17. Fault Mechanism • Intentionally unsophisticated • Simplicity rather than richness • Only one fault: SQIFault • Thrown by all methods • Allows: • Free-text messages • Predefined error codes

18. A Simple Scenario

19. Getting Additional Results

20. Asynchronous Query Mode

21. Federated Search Front End

22. Current Status IT IS HAPPENING NOW ! • Version 1.0 alpha was realeased in Dec. 2004 • Call for comments ended last week • Comments will be reviewed this week in Vienna • CEN/ISSS LTWS meeting in Oslo next week

23. SQI Users Who is using it ? • The ProLearn network of excellence (FP6) • The iClass project (FP6) Who will use it ? • IMS Global SIG “Query Service” • You: • EUN LIFE (workshop + plugfest) • iClass

24. Bindings and Application Profiles Bindings: • Common SQI WSDL • Java Exception Hierarchy Application Profiles: • Celebrate / Ariadne (LOM/VSQL) • Elena / Edutella (RDF)

25. The Celebrate Gateway

26. CeLeBraTe(Context eLearning with Broadband Technologies) • 30 months / € 7 M. project (=>Nov. 2004) • Was supported by the European Commission's IST Program (FP5) • Involved 500 schools across Europe • 22 partners (European ministries of education, universities, leading educational publishers and technology suppliers)

27. Celebrate's Goals Consist in creating: • New contents (LOs) • An innovative pedagogy (based on LOs) • A European learning network (to exchange LOs) • A new business model (Merlin)

28. ELENA ARIADNE CELEBRATE Federation . Brokerage of Networks

29. EUN LMS/LCMS Digitalbrain LMS/LCMS ELN Client ELN Client Messaging Server Sanoma WSOY LMS/LCMS Giunti LMS/LCMS ELN Client ELN Client ELN Client Brok. System Central serv. Federated Search

30. EUN LMS/LCMS Digitalbrain LMS/LCMS ELN Client ELN Client Messaging Server Sanoma WSOY LMS/LCMS Giunti LMS/LCMS ELN Client ELN Client ELN Client Brok. System Central serv. Federated Search

31. EUN LMS/LCMS EUN LMS/LCMS Digitalbrain LMS/LCMS Digitalbrain LMS/LCMS ELN Client ELN Client ELN Client ELN Client Messaging Server Messaging Server Sanoma WSOY LMS/LCMS Sanoma WSOY LMS/LCMS Giunti LMS/LCMS Giunti LMS/LCMS ELN Client ELN Client ELN Client ELN Client ELN Client ELN Client Brok. System Central serv. Brok. System Central serv. Federated Search

32. EUN LMS/LCMS EUN LMS/LCMS Digitalbrain LMS/LCMS Digitalbrain LMS/LCMS ELN Client ELN Client ELN Client ELN Client Messaging Server Messaging Server Sanoma WSOY LMS/LCMS Sanoma WSOY LMS/LCMS Giunti LMS/LCMS Giunti LMS/LCMS ELN Client ELN Client ELN Client ELN Client ELN Client ELN Client Brok. System Central serv. Brok. System Central serv. Federated Search

33. EUN LMS/LCMS EUN LMS/LCMS Digitalbrain LMS/LCMS Digitalbrain LMS/LCMS ELN Client ELN Client ELN Client ELN Client Messaging Server Messaging Server Sanoma WSOY LMS/LCMS Sanoma WSOY LMS/LCMS Giunti LMS/LCMS Giunti LMS/LCMS ELN Client ELN Client ELN Client ELN Client ELN Client ELN Client Brok. System Central serv. Brok. System Central serv. Federated Search

34. SQI SQI SQI Messaging Server ELN Client SQI SQI ELN Client Brok. System Central serv. SQI Gateway

35. ELENA ARIADNE . Brokerage of Networks

36. Architecture administrator Configuration file Brokerage System Gateway Connection SQI Admin ELN Cl ient SQI Core SQI S Q I SQI Translation

37. Translation package Query translation VSQL (xml instance) CELEBRATE Filter (xml instance) IEEE LOM Resultset (xml instance) Results translation Using: - XSLT ( the Extensible Stylesheet Language Transformations) - JAXB (Java Architecture for XML Binding) - JAXP (Java API for XML Processing) Implementation CELEBRATE Resultset (xml instance)

38. The Celebrate Gateway • Supports: • Very Simple Query Language (VSQL) • Simple School Query Language (S2QL) • Strict LOM • Accepts queries in asynchronous mode • Propagates both synchronous and asynchronous queries

39. The iClass Adapter

40. iClass • Develops an Intelligent distributed Cognitive-based Learning System for Schools • Funded under the FP6 • Initiated in January 1, 2004 • 22 partners from 11 countries

41. iClass Adapter • Enables the end-users of “legacy systems” to search and access iClass Learning Objects • Is based on SQI

42. Components

43. Sequence Diagram

44. SQI http://www.prolearn-project.org/lori http://sqi-wsdl.sourceforge.net/