Tutorial on XML Tag and Schema Registration in an ISO/IEC Metadata Registry Open Forum 2003 on Metadata Registries Tuesday, January 21, 2003; 4:45-5:30 p.m. January 2003 Kathleen Gundry Science Applications International Corporation (SAIC)

Open Forum 2003 on Metadata Registries 2 Overview  Identify various information assets to be managed in registries.  Identify the relevant standards for management of those assets.  Present the benefits of combining the management functions in a single registry.  Present the architecture of a registry that might meet the various standards for managing a variety of organizational metadata.  Present the current plans to register XML objects in a metadata registry, the EPA’s Environmental Data Registry.

Open Forum 2003 on Metadata Registries 3 Purpose of a Metadata Registry  The purpose of a metadata registry is to collect and manage information about an organization’s information assets.  The registry is supposed to centralize that information, and improve the organization’s ability to manage it.  Registries should be able to promote reuse of data, identify opportunities for information integration, identify duplicate information collections, promote standardization.

Open Forum 2003 on Metadata Registries 4 Types of Metadata and Related Registry Standards  Data Elements: ISO/IEC 11179, Data Element Metadata Registry  Information Resources: Dublin Core  Data Sets, Spatial Data: FGDC Content Standard for Digital Geospatial Metadata  XML: OASIS/ebXML Registry standard

Open Forum 2003 on Metadata Registries 5 Central Registry Proliferation Enterprise Application Inventory XML Registry Document Management System Data Set Metadata Data Element Metadata

Open Forum 2003 on Metadata Registries 6 Taming Metadata Chaos at EPA Legacy Databases Environmental Information Warehouse Terminology Reference System termsregulated substances Substance Registry System Facility Registry System facility data Environmental Information Management System data sets Information Resources Registry System all sources Environmental Data Registry data elements eXtensible Markup Language Metadata XML objects System of Registries

Open Forum 2003 on Metadata Registries 7 Finding a Place for XML Metadata  OASIS and ebXML have combined their efforts to build a standard for an XML Registry.  A freeware, alpha version of an XML Registry, conformant with the current version of the standard is available from Sourceforge.  There are several commercial XML registry products, but none currently available completely conform to the standard.  Some organizations, including the Environmental Exchange Network, seek to link their XML metadata to other enterprise metadata, like data standard metadata.

Open Forum 2003 on Metadata Registries 8 Managing XML Metadata in the EDR  EPA and its State and Tribal Nation partners have a long term goal of building an Environmental Exchange Network based on environmental data standards.  The Environmental Exchange Network partners identified a need to link XML schema to related data standards.  With no available commercial products meeting that need, the group chose to register XML schema in the EDR as an interim solution.  XML components will be registered in the EDR, without changing the underlying ISO/IEC conformant metamodel.

Open Forum 2003 on Metadata Registries 9 Registering XML Tags  Conceptually, an XML tag = a data element.  XML tags are registered as designations (alternate names) for data elements.  In the EDR, standard XML tags are registered as designations for standard data elements  They use the standard data element name and follow the standard XML tag naming conventions  XML tags as data elements.  In the EDR, XML tags from XML schemas will be registered as data elements because the tags do not always have a one-to-one relationship with an application data element  The application XML tags can be linked to the application data elements.

Open Forum 2003 on Metadata Registries 10 Registering XML Schemas  XML Namespaces, XML Schemas, XML Datatypes, and other grouping XML objects will be registered as Classification Schemes.  defines Classification Scheme as “the descriptive information for the arrangement or division of objects into groups.”  In the EDR Classification Scheme is used to group other elementary objects, such as data elements and value domains. For example, an application system is registered as a Classification Scheme, documented with metadata (name, definition, abstract, submitter), and linked to related data elements and value domains.

Open Forum 2003 on Metadata Registries 11 Registering XML Schemas  Classification Scheme Types will be created and assigned for various grouping XML components.  Linkages between XML objects such as Trading Partner Agreements, XML schema, and other information resources can be stored.  In the EDR, Classification Schemes can be related to other Classification Schemes through Classification Scheme items, creating hierarchical relationships.

Open Forum 2003 on Metadata Registries Model Elements XML schema XML data type Other XML “group objects” Elementary XML tag metadata - definition - type - size Names or “XML tags” For elementary tags or XML group objects Indicator for designation type - XML tag - Registry name - XML schema Classification Scheme Data Element Value Domain Designation Context enumerations through classification scheme item

Open Forum 2003 on Metadata Registries 13 Linking XML Tags to Schemas  The long-term plan is to link XML tags to related XML schemas through data elements.  This linkage is supported by the metamodel.  It can be used to track data standards conformance of XML schemas.  It can be used as a data administration tool to understand what information is being exchanged by the different XML schemas—to foster integration and harmonization.

Open Forum 2003 on Metadata Registries 14 Tracking XML Schema Status  The ISO/IEC standard provides registration and administrative statuses to track metadata objects through the review and approval process.  In the EDR, an additional status field will be added to record the progress of the XML schema through the review and approval process to track the progress of the schema through the process, using the W3C defined statuses.

Open Forum 2003 on Metadata Registries 15 XML Metadata in the EDR  The EDR will be used to store both XML tags and XML documents, with no changes to the underlying model.  Some new queries will be developed to allow users to search for XML schema based on submitting organization, subject, and status— these are simply modifications to current application system/information resource queries.

Open Forum 2003 on Metadata Registries 16 Registry Model Comparisons  The ISO/IEC and the OASIS/ebXML metamodels have much in common.  By extending one of the models, an organization could manage both data element and XML objects in a single registry.

Open Forum 2003 on Metadata Registries 17 Future of XML Management  XML metadata is related to data element metadata, so some linkages between the metadata is desirable.  The Environmental Exchange Network is committed to building XML schemas based on approved data standards.  Data standards will be stored in a metadata registry.  XML schemas need to be related to the data element metadata either through storage in a single registry, or through linkages between two registries.

Open Forum 2003 on Metadata Registries 18 For More Information Kathleen Gundry Science Applications International Corporation A