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PlanetDR, a scalable architecture for federated repositories supporting IMS Learning Design Josep Blat, David Griffiths , Toni Navarrete, José Luis Santos, Pedro García, Jordi Pujol Paper presentation, TENCompetence workshop, Sofia, March 31st 2006. The problem (1). 1 Islands of resources
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PlanetDR, a scalable architecture for federated repositories supporting IMS Learning DesignJosep Blat, David Griffiths, Toni Navarrete, José Luis Santos, Pedro García, Jordi PujolPaper presentation, TENCompetence workshop, Sofia, March 31st 2006
The problem (1) 1 Islands of resources • Many specifications have been proposed for distributed content repositories, e.g. • Ariadne • Edutella • Pond • Lack of interoperability leads to content islands exist of tagged LOM contents only available to small groups
Problem (2 & 3) 2 The use of zip files replicated locally (as in Content Packaging) runs counter to trends to dymanically updated remote resources and web services 3 Integration with users’ workflows is poor
Problem 1. Islands of resources • IMS Digital Repository Interoperability (DRI) is intended to enable server interoperability • Provides functional architecture and reference model. • Aims at very broad recommendations, and resolution of operational issues is left to developers. • This leaves many open questions about implementation and effectiveness
PlanetDR ECL support • Edusource Communication Lanaguage (ECL) is a concrete instance of DRI • Planet is a Spanish nationally funded project. • PlanteDR the first Open Source repository which fully implements LOM, DRI and ECL • Intended for very large federated educational digital repositories
Federation • Edusource content servers are standalone and “unaware” of other content servers in the eduSource network • They are linked together by hand at a central location. • This limits scalablilty • PlanetDR has a federation mode which supports plug & play decentralized management of PlanetDR compatible servers,
Problem 2: zip files v. web services (1) • Content Packaging is closer to the world of CD Roms than to web services,. • Difficult to make full use of distributed resources, continually updated • Imposes downloading, re-packaging. • More natural perspective in the context of the Web is to link directly to the (distributed) resource(s).
Problem 2: zip files v. web services (2) • The work done in UNFOLD and now in TENCompetence is important for squaring this circle. • PlanetDR makes a contribution in this direction
PlanetDR services • Planet web services include • search • submit • Request • Through ECL, can invoke any web services from other content servers in the eduSource network.
Problem 3. Workflow support for Learning Designers • PlanetDR, like other repostiories, supports search and retrieval of resources based on LOM as an isolated task, • A much more natural working context is to perform this task when an author is designing a UoL, and to be able to include the resources retrieved in the UoL.
Integration with Reload • The Reload editor has been extended to allow to search and retrieve resources from the PlanetDR repository, and include them in the workflow of UoL production. • New window added to Reload where the user specifies the fields for searching the resources in the repository • Name • Keywords • format.
Integration with Reload (2) • The tool builds an XQuery statement, which is sent to the repository and executed. • Results returned, and user selects resources for download as a content package • This uses the search and request web services of the PlanetDR repository
More information and downloads • http://planet.urv.es/planetdr/ • jordi.pujol@urv.cat • New release will shortly be available