A centre of expertise in digital information management UKOLN is supported by: The JISC IE Metadata Schema Registry & Metadata Application Profiles British Library, Boston Spa Tuesday 24 May 2005 Pete Johnston Research Officer, UKOLN

A centre of expertise in digital information management Metadata Schema Registry Application that provides services based on information about "metadata terms" (and related resources) "Metadata term" = "unit of meaning" deployed in metadata descriptions Functions might include –Disclosure/discovery of information about "terms" –Verification of provenance/status of "terms" –Discovery of relationships between "terms" support for mapping, inferencing –Pointers to related resources usage in metadata application profiles, guidelines for use, bindings Support for services to human readers, software agents

A centre of expertise in digital information management IEMSR project Funded under JISC Shared Services programme, Jan 2004 – July 2005 –UKOLN, University of Bath –ILRT, University of Bristol CETIS, Becta as "contributing partners" –advice, evaluation, assistance with liaison with users Building on previous work in MEG Registry Project (JISC/Becta), CORES (European Commission)

A centre of expertise in digital information management IEMSR project Primary outputs –Description of requirements –Models for metadata application profiles –Pilot metadata schema registry service –Pilot Web site –Data creation tool(s) for DC & LOM implementers (plus documentation) –Open-source software –Recommendations re policy framework

A centre of expertise in digital information management IEMSR project Outcomes –Consensus on models for DCAP, LOMAP –Improved disclosure/discovery of metadata semantics –Foundation for richer services (mapping, inferencing etc) Benefits –Consistency in creating APs –Collaboration between LOM and DC communities –Wider access to/re-use of existing solutions –Reduced duplication of developer effort –Improved interoperability between applications

A centre of expertise in digital information management IEMSR project: Progress Investigation of user requirements –CETIS, Becta, –Curriculum Online/Tagging Tool, JORUM Functional requirements document Data models for DC AP, LOM AP –RDF binding for models Registry server Web site –Initial prototype; tabbed browse Data Creation Tool Workshop (March 2004) Evaluation by ESYS

A centre of expertise in digital information management Metadata Application Profiles

A centre of expertise in digital information management Metadata Application Profiles Metadata standards provide sets of "terms", defined to support some function –resource discovery, resource (re)use, preservation etc Implementers adopt metadata standards in pragmatic way –optimise for requirements of application Metadata "application profile" as declaration of usage –(re-)use of previously defined terms –customised for context of application –may reference "terms" from multiple sources ("mixing and matching")

Namespace Schema 1 Namespace Schema 2 Application Profile A Application Profile B

A centre of expertise in digital information management The trouble with "terms" "Metadata terms" defined with reference to conceptual frameworks ("meta-models") Multiple frameworks/meta-models exist Different metadata standards reference different meta-models/frameworks –possibly incompatible "Metadata terms" of different types –used in different ways –not necessarily directly comparable Comparison (match) and combination (mix) must always take framework into account Consider DC and LOM….

A centre of expertise in digital information management DCMI Abstract Model DC metadata description as set of statements about a subject resource Each statement –describes a relationship between the subject resource and a second resource (value) –consists of a reference to a property a reference to a value (optionally) a reference to an encoding scheme All DC "elements" are properties –related by (e.g.) refinement/subproperty relationships Metadata applications typically based on description sets –sets of descriptions of (related?) resources

Resource URI Property URIRich representation Property URIValue URIVocab Enc Scheme URI Property URIValue stringSyntax Enc Scheme URI Statement Resource URI Property URIRich representation Property URIValue URIVocab Enc Scheme URI Property URIValue stringSyntax Enc Scheme URI Description Description Set

A centre of expertise in digital information management LOM "Abstract Model" No explicit LOM abstract model IEEE LOM standard defines LOM instance as hierarchical tree/container structure LOM data element is component in hierarchy –aggregate LOM data elements –simple LOM data elements –related by containment relationships Each Simple LOM data element is associated with –LOM datatype –Value space Reference to a standard LOM Vocabulary

Category Element Element LOM Instance Value

A centre of expertise in digital information management DC AM & LOM AM DCAM & "LOM AM" describe –the types of terms that are used in metadata descriptions –how those terms are used in combination –how those combinations of terms should be interpreted But –different types of terms DC Element ! = LOM Data Element –used in different ways Statements v documents –interpreted according to different rules So "reuse" of "terms" across models potentially problematic if models not compatible

A centre of expertise in digital information management DC Application Profile Specifies which properties occur in a class of description sets Does not define new properties –References ("uses") properties already defined DCAP as set of "property usages" May –provide additional documentation on interpretation of the property –provide an application-specific label –specify constraints on the occurrence of statements referring to the property –specify constraints on the permitted values of the property (i.e. "encoding schemes")

A centre of expertise in digital information management Examples OAI-DC (Simple DC) Application Profile –"Simple DC" –15 properties of DCMES –All optional, all repeatable –Value strings RDN-DC Application Profile –Additional properties from DC Terms, RDN Terms –Encoding Schemes RSLP CD –Multiple resource types

A centre of expertise in digital information management LOM Application Profile Specifies which LOM data elements are used in a class of LOM instances –Subject to constraints in LOM standard May –provide additional information on how LOM Data Elements are interpreted in the context of the application –specify obligation for use –describe constraints on their occurrence –specify the use of vocabularies to provide values for LOM data elements where the datatype in the LOM standard permits –specify taxonomies and classification schemes for use for specified 'purposes' with the LOM Classification data element

A centre of expertise in digital information management Examples UK LOM Core –Usage of IEEE LOM to support disclosure/discovery/access/use of UK learning resources RDN LTSN LOM Application Profile –Disclosure/discovery/access/use –Record sharing between RDN and LTSN partners over OAI-PMH

A centre of expertise in digital information management DC AP v LOM AP Both describe information models for sets of instances DC AP describes class of DC metadata description sets –by specifying terms (properties, classes) used LOM AP describes class of LOM instances –by specifying constraints on LOM tree structure DC Element != LOM Data Element DC AP != LOM AP Applications working across DC and LOM must take into account different meta-models

A centre of expertise in digital information management The IEMSR and the IE

A centre of expertise in digital information management The IEMSR and the IE Effective exchange of metadata essential to interoperability –IE Technical Standards specify "baseline" of Simple DC and/or UK LOM Core Serialised using specified XML bindings Also exchange of richer/different metadata –use of additional metadata "application profiles" –introduction of new "metadata terms" Increasing requirement to disclose information about new "metadata terms" –Issues of authority, currency, provenance, trust

JISC-funded content providers institutional content providers external content providers brokersaggregatorscataloguesindexes institutional portals subject portals learning management systems media-specific portals end-user desktop/browser presentation fusion provision OpenURL resolvers shared infrastructure authentication/authorisation (Athens) JISC IE service registry institutional preferences services terminology services user preferences services resolvers IEMSR (based on Andy Powell's JISC IE Architecture diagram)

A centre of expertise in digital information management The IEMSR and the IE IEMSR as shared/infrastructural service –Machine interface(s) ("structured") However… metadata exchange in IE currently based on prior co-ordination between human data/service providers on metadata formats –typically based on XML rather than on higher-level data models –limited/controlled extensibility? –no “unknown terms”?

A centre of expertise in digital information management IEMSR: Use Scenarios Metadata creation tool accesses machine- readable description of selected application profile –Obligation/occurrence constraints –Human-readable documentation for help info/tool tips –Controlled vocabularies/encoding schemes –Schemas for bindings Presentation service requires information on selected application profile –What labels to use in display of harvested records N.B. Application needs prior knowledge of mapping between AP info model and binding

JISC-funded content providers institutional content providers external content providers brokersaggregatorscataloguesindexes institutional portals subject portals learning management systems media-specific portals end-user desktop/browser presentation fusion provision OpenURL resolvers shared infrastructure authentication/authorisation (Athens) JISC IE service registry institutional preferences services terminology services user preferences services resolvers IEMSR metadata portal (based on Andy Powell's JISC IE Architecture diagram)

A centre of expertise in digital information management The IEMSR and the IE Presentational service based on data from IEMSR –Human-readable interface ("unstructured") "Metadata portal" for the IE –Disclose/discover metadata semantics, usage –Promote appropriate reuse of existing solutions –Minimise duplication of effort

A centre of expertise in digital information management IEMSR: Use Scenarios Content provision service provider discloses application profile –Constructs & publishes description, submits to registry Metadata schema developer explores/(re-) uses existing implementation choices –Selects terms for reuse in new application profile –Concerns of status, provenance, trust Researcher surveys existing usage of metadata standards –How terms used in practice (within domain, community, area)

A centre of expertise in digital information management The IEMSR Architecture & Tools

A centre of expertise in digital information management IEMSR Development Software development by ILRT –Dave Beckett, Nikki Rogers, Simon Price –RDF used throughout Registry server –Redland, MySQL, Perl –REST interfaces, supporting SPARQL –redevelop as Java application using Jena? Web Site –Java J2EE application –Apache Struts: Tiles, Java Beans Data Creation Tool –Java application, Eclipse SWT+Jface libraries

IEMSR Registry Server IEMSR Web Site Other Presentational Service IEMSR Data Creation Tool Other Data Creation Tool API Data Source

IEMSR Registry Server IEMSR Web Site API response data RDF Data Source IEMSR Data Creation Tool

A centre of expertise in digital information management

A centre of expertise in digital information management

A centre of expertise in digital information management Query registry server

A centre of expertise in digital information management Select property to use

A centre of expertise in digital information management Describe how property used in this DCAP

A centre of expertise in digital information management Query again; select again

A centre of expertise in digital information management Select encoding scheme

IEMSR Registry Server IEMSR Web Site IEMSR Data Creation Tool API query results IEMSR Web Site

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Browse Agency list

View DCAP

Browse Agency list

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View Metadata Vocabulary

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A centre of expertise in digital information management Issues, challenges, thoughts

A centre of expertise in digital information management Issues, challenges, thoughts Complexity of working with multiple meta-models –Not only an issue for IEMSR or AP developers, but for other applications working across LOM and DC metadata –Ongoing discussions between DCMI and IEEE LOM communities Centralised v distributed registry services –IEMSR as "semi-distributed" Reads/indexes data distributed on Web But single point of provision of service –Distributed model?

A centre of expertise in digital information management Issues, challenges, thoughts Users of machine-oriented IEMSR interfaces –demonstrate usefulness as m2m service? IEMSR and other shared services –IEMSR as component in JISC IE –used in combination with other components, including other shared services –e.g. "which services deploy DCAP D or binding B?" IEMSR + IESR Scope/policy issues –which standards/profiles/terms are "in scope"? –authority, status, provenance, trust –"who says what about what"

A centre of expertise in digital information management UKOLN is supported by: The JISC IE Metadata Schema Registry & Metadata Application Profiles British Library, Boston Spa Tuesday 24 May 2005 Pete Johnston Research Officer, UKOLN