® © 2006 Open Geospatial Consortium, Inc. OGC Catalog CEOS WGISS-22 12 September 2006 Chuck Heazel [email protected].

© 2006 Open Geospatial Consortium, Inc.© 2006 Open Geospatial Consortium, Inc.

®

OGC CatalogOGC Catalog

CEOS WGISS-22 CEOS WGISS-22 12 September 2006 12 September 2006

Chuck Heazel

[email protected]

© 2006 Open Geospatial Consortium, Inc. 2OGC®

What is the OGC?What is the OGC?

Open Geospatial Consortium, Inc. (OGC)

Not-for-profit, international voluntary consensus standards organization

Founded in 1994, Incorporated in US, UK, Australia

320+ (up from 270 last year) industry, government, research and university members

OGC Mission

To lead in the development, promotion and harmonization of

open spatial standards …

© 2006 Open Geospatial Consortium, Inc. 3OGC®

OGC’s Approach for Advancing InteroperabilityOGC’s Approach for Advancing Interoperability

Specification Development Program – Consensus standards process similar to other Industry consortia (World Wide Web Consortium, OMA etc.).

Outreach and Community Adoption Program – education and training, encourage take up of OGC specifications, business development, communications programs

Interoperability Program – a global, innovative hands-on rapid prototyping and testing program designed to accelerate interface development and validation and to bring interoperability to the market.

© 2006 Open Geospatial Consortium, Inc. 4OGC®

Iterative DevelopmentIterative DevelopmentYielding Tested SpecificationsYielding Tested Specifications

Interoperability Program

Specification Program

Outreach Program

Draft Specifications

Adopted Specifications

Holes and Enhancements

SCOTS Implementations

Prototype Implementations

Requirements

© 2006 Open Geospatial Consortium, Inc. 5OGC®

OGC CatalogOGC CatalogHistoryHistory

• In February 1999, MITRE and USGS/NASA both presented proposals to the OGC Technical Committee for a Catalog service.

• A tiger team was formed to converge the two proposals into a single specification.

• The resulting OGC Catalog Specification was presented and approved at the OGC Technical Committee meeting of August 1999.

• At this meeting prototype implementations of the specification were demonstrated interacting with each other.

© 2006 Open Geospatial Consortium, Inc. 6OGC®

OGC CatalogOGC CatalogBackgroundBackground

• Catalog specification contains an abstract model (captured in UML) and Distributed Computing Platform (DCP) specific profile specifications.

• Goal was to enable cross-DCP access to a catalog service.• Initial set of supported profiles were for:

– CORBA– DCOM– Z39.50

• Catalogs are data model agnostic.• An “explain collection” interface describes the data model.• An “explain service” interface returns a service description.

© 2006 Open Geospatial Consortium, Inc. 7OGC®

OGC CatalogOGC CatalogBackgroundBackground

• Mandatory interfaces were defined for:– Explain Service– Explain Collection– Query

• Optional interfaces were defined for:– Management (population and update)– Federation (delegating a query to other catalogs and aggregating

the responses)

• A language was defined for geospatial data queries.

© 2006 Open Geospatial Consortium, Inc. 8OGC®

Web ServicesWeb Services

• In 1999 the OGC began work on Web Services in the Web Map Server testbed (WMS-1).

• The OGC Catalog Specification did not provide stateless interfaces which are required for Web Services.

• The basic Catalog (Registry) technology was evaluated over subsequent testbeds.

• OGC Catalog Services 2.0.1 is the current version

© 2006 Open Geospatial Consortium, Inc. 9OGC®

OGC Catalog InterfacesOGC Catalog Interfaces

• Get Capabilities Interface– Required for all services

– Advertises the service and provides sufficient detail for Bind operations

– Is invoked by some Catalogs to maintain metadata currency

• Query Interface– Required for Catalogs

– Returns metadata on Catalog entries satisfying a filter criteria

• Transaction Interface– Optional for Catalogs

– Supports maintenance of the Catalog entries

• Distributed Query (still being worked)– Optional for Catalogs

– Supports distribution of a query over multiple Catalogs

© 2006 Open Geospatial Consortium, Inc. 10OGC®

Web Resources ModelWeb Resources Model

My

Resource

Information Framework

Resource

Publish

Find

Bind

© 2006 Open Geospatial Consortium, Inc. 11OGC®

The Model Requires ---The Model Requires ---

• A forum where resources can advertise their capabilities and users can find the resources they need.

• Self describing resources so that user applications can bind at run-time to the resources that they have found.

© 2006 Open Geospatial Consortium, Inc. 12OGC®

Self Describing ResourcesSelf Describing Resources

• Resources are provided by Services.• Each service supports a “get capabilities” interface.• Get Capabilities provides a robust set of metadata (a

Capabilities Document) describing the service, the behavior, contents, and how to bind to it.

• Services that provide access to data also describe their data holdings through the content section of the Capabilities Document.

• Goal is to enable binding with or without human intervention

© 2006 Open Geospatial Consortium, Inc. 13OGC®

Web Resources ModelWeb Resources Model(with automated update)(with automated update)

My

Resource

Resource

URL

Find()

Execute

Get_Capabilities()

Metadata Doc.

ResultsGet_Capabilities()

Capabilities Doc.

Catalog

Application

© 2006 Open Geospatial Consortium, Inc. 14OGC®

OGC Catalog layered standardOGC Catalog layered standard

OGC_Service, Discovery, Manager, “Record”

Abstract Interfaces and Operations (technology and information agnostic

HTTP (Catalog Service / Web)Protocol Bindings (information agnostic)

ebRIM* Profile, ISO191xx ProfileInformation Model

* incoming records representing different metadata standards are managed within a single catalog schema or

registry information model, ebRIM.

Ingestion, Search, Presentation (Lifecycle)Domain Services

© 2006 Open Geospatial Consortium, Inc. 15OGC®

Catalog MetadataCatalog Metadata

• Registry Metadata Model– ebXML Based (EbRIM)

• Metadata for Data Resources– ISO 19115– FGDC-STD-001-1998

• Metadata for Services– WSDL - interface and binding– ISO 19119 - service taxonomy– Services Information Model - full service description

• Metadata for Sensors– Developed for stationary sensors under OWS 1.1– Extended for mobile sensors under OWS 1.2– Matured under OWS-3

© 2006 Open Geospatial Consortium, Inc. 16OGC®

OWS-4 Catalog Work ItemsOWS-4 Catalog Work Items

• Catalog– CS/W ebRIM - SOAP

• Data registry• Services registry• Style registry• Sensor registry

– Query at Feature Level– Support for DGIWG Portal

• Compliance Testing– Beta test new Open Source engine

– Develop Scripts & Tests for CS/W 2.0.1– Develop CS/W 2.0.1 Reference Implementation

© 2006 Open Geospatial Consortium, Inc. 17OGC®

Comments RequestedComments Requested

OGC Catalog Working Group and JAG proposed at the October 2006 Technical Comittee that:– the ebRIM be adopted as the only (cataloguing) metamodel for all

OGC CS-W Catalogue implementations– Application Profile as understood in CSW be redefined to mean an

extension package of ebRIM– ISO Metadata AP be migrated to an ebRIM extension package

consistent with the previous two items