OGC-compliant s ervices and how they are used in NAS

1. OGC-compliant services and how they are used in NAS Presented to: EES By: Leonid Felikson, Dovel Technologies

2. Agenda • What are OGC-compliant services? • What is geospatial data? • What is the Open Geospatial Consortium (OGC)? • What is Geography Markup Language (GML)? • GML extension in aviation • OWS Common in FAA • Web Feature Service (WFS), Web Coverage Service (WCS) and Web Map Service (WMS) • Examples of OGC-compliant services in NAS • Q&A

3. What are OGC-compliant services? • Geospatial data is data that contains geographical references. • Open Geospatial Consortium (OGC) is an international organization that develops open standards for GIS processing and geospatial data and services. • OGC-compliant services are SOA (Web) services that are built according to the specifications set forth by the OGC.

4. What is geospatial data? Geospatial data or geographic informationis the data or information that identifies the geographic location of features and boundaries on Earth, such as natural (i.e. rivers, etc.) or constructed (i.e. buildings, etc.) features, oceans, and more. • Spatial data is usually stored as coordinates and topology, and is data that can be mapped. • Spatial data is often accessed, manipulated or analyzed through Geographic Information Systems (GIS). • Most of this data is stored in different data formats, using different data models, coordinate reference systems, geometry models, etc. • Thus, sharing geospatial data has required considerable time, expertise and special software.

5. What is the OGC? The Open Geospatial Consortium (OGC) is a consortium of companies, non-governmental organizations (NGOs), research organizations, agencies and universities with a common vision in which everyone benefits from geographic information and services made available across any network, application, or platform. The OGC mission is: • to promote the development and use of advanced open systems standards and techniques in the area of geoprocessing and related information technologies; • to manage a global consensus process that results in approved interface and encoding standards that enable interoperability among and between diverse geospatial data stores, services, and applications.

6. Geography Markup Language Geography Markup Language (GML) is the XML grammar defined by the OGC to express geographical features. • GML is: • a modeling language for geographic systems; • used to enable an open interchange format for geographic transactions; • focused on the description of geographic content; • relying on use of other languages and standards like KML (Keyhole Markup Language)or SVG (Scalable Vector Graphics)for graphical presentation; • using a GML schema. This allows users and developers to describe generic geographic data sets that contain points, lines and polygons. • GML is not: • a presentation standard; so it can’t be used for drawing maps; • carrying properties like line thickness or color.

7. Example of GML The following GML example illustrates the distinction between features and geometry objects. Note:The Building feature has several geometry objects, sharing one of them, the Point(with identifier p21), with the SurveyMonument feature. <abc:Buildinggml:id="SearsTower"> <abc:height>52</abc:height> <abc:positionxlink:type="Simple" xlink:href="#p21"/> </abc:Building> <abc:SurveyMonumentgml:id="g234"> <abc:position> <gml:Pointgml:id="p21"> <gml:posList>100,200</gml:posList> </gml:Point> </abc:position> </abc:SurveyMonument>

8. GML extension in aviation • OGC standards support Aviation Information Management (AIM) • Several of the world's major government aviation organizations working with large and small aviation companies are now far along in the development and adoption of the Aeronautical Information Exchange Model (AIXM), the Weather Information Exchange Model (WXXM), and the Flight Information Exchange Model (FIXM).

9. GML extensions used in NAS • The Aeronautical Information Exchange Model(AIXM) is based on the OGC GML Encoding Standard to ensure alignment with international standards for location information and to ease its adoption by technology providers that already support GML in their Commercial-Off-The-Shelf (COTS) products. • The Weather Information Exchange Model (WXXM) is being developed as a standard for the exchange of weather information in support of aviation meteorology (MET) domain requirements. • The Flight Information Exchange Model (FIXM) is a data interchange format for sharing information about flights throughout their lifecycle.

10. OWS Common used in FAA OGC Web Service (OWS) Common Web Map Service (WMS) Web Feature Service (WFS) Web Coverage Service (WCS)

11. OWS Common used in FAA, cont’d. • OGC Web Services (OWS) Common describes common capabilities across all OGC web services. • Web Feature Service Interface Standard (WFS) provides an interface allowing requests for geographical features across the Web using platform-independent calls. • Web Coverage ServiceInterface Standard (WCS) defines Web-based retrieval of a coverage – that is, digital geospatial information representing space/time-varying phenomena. • Web Map Service (WMS) is a standard protocol for serving geo-registered map images over the Internet that are generated by a map server using data from a GIS database.

12. OGC-compliant vs. Web services (WS*) OGC –compliant services and Web services (WS*) are both standard-based, self-describing and designed primarily for synchronous message exchange patterns. • OGC services are defined specifically for geospatial data – Web services are data neutral. • OGC services use the uniform set of operations (methods) defined by OGC interface specifications – Web services expose an arbitrary set of operations. • OGC services require Capabilities document and stand-alone XML schema – Web services require WSDL. (Note: OGC services may use WSDL as well.)

13. How OGC services are documented • Requirements for OGC-compliant services shall be specified in Web Service Requirements Documents (WSRD). • Service descriptions shall be presented as Web Service Description Documents (WSDD). • WSDL files should be generated for all OGC-compliant services. • XML Capabilities and Feature XSD files shall also be presented. • In some cases, an External Data Description document may be provided to augment a WSDD. • All documents shall be uploaded into the NAS Registry/Repository (NSRR).

14. CIWS CDDS (FAA example 1) • The Corridor Integrated Weather System (CIWS) is a fully automated weather analysis and forecasting system, prototyped and operated for the FAA by MIT Lincoln Laboratory (MIT LL). • CIWS combines data from U.S. and Canadian weather radars with satellite data, surface observations, and numerical weather models to dramatically improve the accuracy and timeliness of storm severity information, and to provide accurate, rapidly updating weather information to air traffic flow managers. • CIWS benefits are allowing managers to achieve more efficient tactical use of national airspace, reduce controller workload, and significantly reduce delay. • Through the CIWS Data Distribution Service (CDDS), both NAS and non-NAS users can now obtain the CIWS gridded and non-gridded products via SWIM-compliant SOA-enabled web services. • Both request/reply and publish/subscribe interfaces to the data are available.

15. WINS WCS (FAA example 2) • Weather Information Network Service (WINS) Web Coverage Service (WCS) provides gridded weather data including the Rapid Refresh (RAP) Continental United States (CONUS), Global Forecast System (GFS), and North American Mesoscale (NAM) forecast models, as well as the Aviation Weather Center’s (AWC) Current Icing Product (CIP) and National Convective Weather Diagnostic (NCWD). • The WINS implements the OGC WCS standard which provides a highly flexible interface to potential consumers. • WINS WCS service consumers include: • Weather and Radar Processor (WARP) • CAASD Analysis Platform for En-Route (CAPER) • Surveillance and Broadcast Services (SBS) • NextGen Surface Prototype System (NSPS)

16. WINS WCS, cont’d. • The WINS WCS provides business functionality to satisfy a consumer’s need for timely and accurate weather information such as numerical forecast model, icing forecast, and convective forecast data. • The service interface is a collection of types, messages, operations, and interface descriptions. It provides detail on how the WCS data is constructed independent of the messaging transmission technology. • The WINS WCS service interface is composed of two specifications: • the OGC WCS specification and • the OASIS Web Service Notification (WSN) specification.

17. References • OGC® Standards and Supporting Documentshttp://www.opengeospatial.org/standards • http://www.aixm.aero • http://www.wxxm.aero • http://www.fixm.aero • OGC Web Services Common at http://portal.opengeospatial.org/files/?artifact_id=38867 • WFS 2.0 at http://portal.opengeospatial.org/files/?artifact_id=39967 • WCS 2.0 at https://portal.opengeospatial.org/files/09-110r4 Contact Information: Mark Kaplun, SWIM Governance Lead (mark.kaplun@faa.gov) Leonid Felikson (leonid.CTR.felikson@faa.gov)

18. Q &A

19. Thank You!