The Next Generation Network Enabled Weather (NNEW) SWIM Application

1. SP/8 The Next Generation Network Enabled Weather (NNEW) SWIM Application Asia/Pacific AMHS/SWIM Workshop Chaing Mai, Thailand March 5-7, 2012 Tom McParland, BCI

2. Presentation Overview • Geographic Information Systems (GIS) • Vector Data, Raster Data • OGC Data Access Standards • WCS, WFS, WMS Services • Relationship of Standards • WCS, WFS, WMS Operations and Bindings • NextGen Network Enabled Weather (NNEW) • NNEW and the 4-D Weather Cube • NNEW Interface Extensions • OGC-defined Request/Response and NNEW-defined Pub/Sub • Asia/Pacific SWIM over AMHS • HTTP/X.400 Gateway • JMS/HTTP Gateway

3. Geographic Information Systems • Historically, geographic information has been treated in terms of two fundamental types called vector data and raster data. • “Vector data” deals with discrete phenomena, each of which is conceived of as a feature. The spatial characteristics of discrete real-world phenomenon are represented by a set of one or more geometric primitives (points, curves, surfaces or solids). Other characteristics of the phenomenon are recorded as feature attributes. • “Raster data” deals with real-world phenomenon that vary continuously over space. It contains a set of values, each associated with one of the elements in a regular array of points or cells. Source: ISO 19123:2005

4. OGC Data Access Standards • The Open Geospatial Consortium (OGC) has defined several Data Access services. • Web Feature Service (WFS) provides features (vector data) as a Web service • Web Coverage Service (WCS) provides coverages (raster data) as a Web service • Web Map Service (WMS) provides rendered maps containing a base map with layered feature and coverage data as a Web service

5. OGC WFS, WCS, WMSfor Weather

6. OGC WFS, WMSfor AIM

7. OGC Web Feature Service • Web Feature Service (WFS) defines protocols for requesting GML Features through HTTP requests. • GML Features are geospatial objects such as images or GML documents that describe real-world entities, e.g. meteorological objects (fronts, precipitation areas), weather observation readings, observation stations or roads as a combination of the entities’ geometry (points, lines, or polygons) and attributes (other information about those entities).

8. OGC Web Feature Service • The WFS specification defines three basic operations: • GetCapabilities queries the WFS service to determine available options; • DescribeFeatureType retrieves the XML schema to allow the WFS client to parse the result; and • GetFeature performs the actual query.

9. OGC WFS Operations and Bindings

10. OGC Web Coverage Service • The Web Coverage Service (WCS) is similar to WFS, but instead of images or features deals with coverages, i.e. digital geospatial information representing space-varying phenomena. • WCS operates with gridded data, i.e. collections of mappings from geometry (grid points) into parameter (temperature, pressure, etc.) values. • WCS provides access to intact (unrendered) geospatial information, as needed for client-side rendering, multi-valued coverages, and input into scientific models and other clients beyond simple viewers.

11. OGC Web Coverage Service • Similar to WFS, the WCS client can • request the WCS server for available options using the GetCapabilities operation; • ask the server to describe coverages of interest with DescribeCoverage operation; • and create and return the requested subset of the available coverage data with GetCoverage operation.

12. OGC WCS Operations and Bindings

13. OGC Web Map Service • The OGC WMS produces maps of spatially referenced data dynamically from geographic information. • This standard defines a "map" as a digital image file suitable for display on a computer screen (map is not the data itself). • WMS-produced maps are generally rendered in a pictorial format such as PNG, GIF or JPEG.

14. OGC Web Map Service • WMS defines three operations: • GetCapabilities provides a description of the available information content and acceptable request parameters; • GetMap returns a map as an image; • GetFeatureInfo provides information about features at a point on a map.

15. OGC WMS Operations and Bindings

16. NextGen Network Enabled Weather (NNEW) Source: MIT LL

17. NextGen Network Enabled Weather (NNEW) Source: MIT LL

18. NNEW Message Exchange Patterns NNEW offers the OGC defined request/response services (i.e. WFS, WCS, and WMS Web service interfaces) NNEW has also defined interface extensions to the OGC standard WFS and WMS operations. The extensions enable a client to subscribe to a service and then receive the data or notifications about the data over a publish/subscribe interface.

19. NNEW Protocol Bindings

20. NNEW Exchange Scenarios • An NNEW Service Provider may be configured to support several different types of Exchange Scenarios (i.e., a particular combination of request/response and publish/subscribe service interfaces.) • WFS, WCS, WMS Request/Response (i.e. OGC Request/Response) • WFS Persistent Query Publish/Subscribe • WCS Notify Publish/Subscribe • WFS Static Persistent Query

21. WFS, WCS, WMS Request/Response

22. WFS Persistent Query Publish/Subscribe

23. WCS Notification Publish/Subscribe

24. WFS Static Persistent Query Publish/Subscribe

25. Asia/Pac SWIM over AMHSRequest/Response

26. Asia/Pac SWIM over AMHSRequest/Response and Pub/Sub