1. World Meteorological Organisation (WMO) Observing and Information Systems Department
WMO INFORMATION SYSTEM (WIS) --- COMPLIANCE SPECIFICATIONS OF GISC, DCPC, AND NC
My name is Eliot Christian. I am a consultant to the World Meteorological Organization, Observing and Information Systems Department, headed by Don Hinsman. I am supporting the WMO Information System (WIS) initiative, under direction of Jean-Michel Rainer, with David Thomas as WIS Project Manager.
In 2007, the WMO World Congress (Cg-XV) emphasized the need for WIS, and for WIS to issue appropriate regulatory documentation, including organization and recommended practices and procedures.
The topic of this presentation is the document circulated in December and entitled "Compliance Specifications of GISC, DCPC, and NC".
I am the principal author of that document, which is based on various sources including especially the European VGISC initiative.
Presented 10 June 2008 at the "Ad-hoc Information and Advisory Meeting on the Region VI VGISC-DCPC project" (EUMETSAT, Darmstadt) by Eliot Christian

2. Outline of WIS Compliance Specifications
Purpose and Authority of Specifications
Major Components and Services of WIS
Flow Diagrams amongst WIS Components
Technical Specifications of WIS Interoperable Interfaces
This is an outline of both my presentation and the actual draft WIS Compliance Specifications document:
Purpose and Authority of the Technical Specifications
Vision and Goals of WIS
Major Components and Services of WIS
Flow Diagrams amongst WIS Components
Technical Specifications of WIS Interoperable Interfaces
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

3. Purpose and Authority: Purpose of WIS Specifications
Existing centres within WMO Member States may apply for designation as one of the functional centres forming the core infrastructure of WIS:
Global Information System Centre (GISC)
Data Collection or Production Centre (DCPC)
National Centre (NC)
Designation requires a statement of compliance with required WIS functions, compiled by the Inter-Commission Coordination Group on WIS (ICG-WIS)
The WIS Compliance Specification document provides technical specifications for required WIS functions
Existing centres within WMO Member States may apply for designation as one of the functional centres forming the core infrastructure of WIS:
Global Information System Centre (GISC),
Data Collection or Production Centre (DCPC) and
National Centre (NC)
Such a designation requires a statement of compliance with the required WIS functions. Those requirements are to be compiled and regularly reviewed by the Inter-Commission Coordination Group on WIS (ICG-WIS).
The purpose of this document is to provide Technical Specifications where necessary for required WIS functions.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

4. Purpose and Authority: Authority of WIS Specifications
On approval, the WIS Compliance Specifications will be the authoritative source for technical specifications of interoperable interfaces required of core WIS components across GISCs, DCPCs, and NCs
It was expected that the WIS Compliance Specifications would be useful in an Invitation to Tender on software needed by a prospective WIS DCPC or GISC (e.g., the present European ITT for software to implement a Virtual GISC)
As you know, data collection and exchange systems throughout WMO are evolving their interfaces under the new "system of systems" that is WIS. This evolution is guided by Service Oriented Architecture principles that enable or simplify interoperability among systems. An especially important principle is the need for diverse systems such as WIS to standardize on a small set of interoperable interfaces.
On approval, the Technical Specifications given in the "Engineering Viewpoint" section of the WIS Compliance Specifications will be the authoritative source for "interoperable interfaces" required of GISCs, DCPCs, and NCs. Materials in all other sections of the document can be regarded as informative background.
It was expected that the WIS Compliance Specifications would be useful in an Invitation to Tender on software needed by a prospective DCPC or GISC. The European Virtual Global Information System Centre Invitation to Tender was an obvious opportunity to validate that expectation.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

5. Technical Specifications will be part of WIS "regulatory documents"
From a project perspective, there are now several parallel activities underway, including both "Part A" and "Part B".
Part A focuses on the IMTN (Improved Main Telecommunication Network). Part B concerns implementation of the new capabilities provided by GISC's and DCPC's. That is the focus of the WIS Technical Specifications document as well.
The WIS Technical Specifications will become part of the "Manual on WIS". The Manual on WIS is called out under the "regulatory documents" activity in the WIS Project Plan. As you may notice, this activity and some of the other WIS activities extend several years into the future.
Milestone Activities from WIS Project Plan, version 0.5
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

6. Outline of WIS Compliance Specifications
Purpose and Authority of Specifications
Major Components and Services of WIS
Flow Diagrams amongst WIS Components
Technical Specifications of WIS Interoperable Interfaces
Now, I would like to present the Major Components and Services of WIS.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

7. WIS Compliance Specifications of GISC, DCPC, and NC
Major Components and Services of WIS: Evolution from Global Telecommunications System
WIS builds on the connectivity of the existing WMO Global Telecommunications System (GTS), shown in this schematic. WIS goes a step further by incorporating connectivity available through the Internet, yet taking pains to ensure a data management framework able to encompass all WMO information.
This is a natural evolution: building on GTS while expanding the overall information system. GTS itself has a data management framework with catalogues of metadata for observation stations, and with distribution catalogues delineating where information originated and which Members subscribe to which information.
We could say that WIS introduces a change in focus: from communications-centric (managing connectivity) to data-centric (managing data and products).
Existing National Meteorological and Hydrological Centres, as defined in the Manual on GTS, are expected to become WIS NCs.
Regional Specialized Meteorological Centres (RSMCs) and Regional Telecommunications Hubs (RTHs) are expected to become DCPC's.
The three World Meteorological Centres are expected to become GISCs.
Current centres
WIS Centres
NMHS NC
RSMC
DCPC
WMC
DCPC and/or GISC
RTH
RTH on MTN
Others
NC and/or DCPC
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

8. Major Components and Services of WIS: GISCs, DCPCs, and NCs
WIS defines some distinct roles for GISCs, DCPCs, and NCs.
Every WIS NC must comply with the requirement to supply metadata for their data and products.
DCPCs collect, disseminate, add value to, and archive regional or programme-specific data and products. DCPCs also produce regional or specialised information, and provide related data and products for international exchange. DCPCs maintain catalogues of their holdings and services, and appropriate parts of these catalogues also update a comprehensive catalogue of WIS holdings, hosted by the GISCs.
GISCs disseminate information from NCs and DCPCs within their area of responsibility. GISCs also hold and distribute copies of at least 24 hours of WMO data and products intended for global distribution.
The GISCs also host the comprehensive catalogue for Discovery, Access and Retrieval (the DAR catalogue).
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

9. WIS Compliance Specifications of GISC, DCPC, and NC
Note: GTS Message Switching Systems (MSSs) in the VGISC Invitation to Tender (ITT)
DWD, Meteo-France and UKMO each operate a GTS MSS
The VGISC must interface to MSSs to: - ingest and cache data and metadata - handle subscription and GTS link info - maintain control lists - provide failover support
Each of the three partners is responsible to adapt to the MSS interface provided by the VGISC software
In drafting the European Virtual GISC (VGISC) Invitation to Tender (ITT), the partners realized that bidders need to know exactly the existing GTS will be interfaced to the new system. In particular, the vendors need to know how to interface with existing GTS Message Switching Systems (MSSs).
Here I will quote from the VGISC ITT document:
Three of the VGISC partner sites (DWD, Meteo-France and UKMO) each operate a Message Switching System (MSS) that is connected to the GTS. The VGISC as implemented by these partners must interface to these MSSs in order to ingest and cache data and metadata, to handle subscription and GTS link information, maintain control lists, and provide failover support as necessary. However, among these three partner sites there are not identical MSS control procedures nor a common interface. The VGISC software acquired through this ITT will provide such an interface, and each of the three partners is responsible to adapt to that common interface.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

10. Major Components and Services of WIS: Interoperability and WIS Networking
Data and Product Users
National Centres (NCs)
Global Information System Centres (GISCs)
As described in the WIS Compliance Specifications, WIS is focused on enabling interoperability as encountered at the interfaces among system components.
Focusing on interfaces greatly reduces the complexity otherwise evident across the diverse systems. It also minimizes impacts on any given component system other than at its WIS interfaces. This is very important because the component systems themselves are typically built and managed independently.
Here is a high‑level architectural view of the major parts of WIS. Interoperability opportunities are shown as arrows to users and among GISCs; DCPCs; and NCs. Technical Specifications focus on the points of those arrows, i.e., the interfaces at touch points where WIS components must interoperate.
Architecturally, WIS can be viewed as a Service Oriented Architecture implemented primarily through communications networks. The Technical Specifications presented in the WIS Compliance Specifications are primarily those network services that occur at interfaces between interoperating WIS components.
It might be useful here to briefly look at major programmes of WMO and see how these map onto WIS in these terms.
Data Collection or Production Centres (DCPCs)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

11. Major Components and Services of WIS: WIS and Seven Programmes
The particular systems are:
the Global Atmosphere Watch,
the World Hydrological Cycle Observing System,
the Global Observing System of the World Weather Watch,
the World Climate Programme,
the Global Terrestrial Observing System,
the Global Ocean Observing System, and
the Global Climate Observing System.
(The green versus yellow color merely distinguishes those systems thar are fully within WMO purview.)
Each of these systems are being converged in various ways. All of these systems will use WIS as their main data collection and exchange system.
WIS and each of the seven WMO systems addressed herein are also viewed as contributed systems to the Global Earth Observations System of Systems.
I will also note in passing that WMO has a related initiative called the WMO Integrated Global Observing Systems (WIGOS). WIGOS builds on WIS but focuses more on enhancing the comparability of observations and interoperability of observing systems.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

12. Major Components and Services of WIS: Global Atmosphere Watch (GAW)
Data and Product Users
National Centers (includes WIS NC's)
GAWSIS Web site
Observing systems contributing to GAW
WIS Global Information System Centres (GISC's)
GAW Web site
World Data Centres (also known as WIS DCPC's)
Here is a cartoon showing some GAW components as described in WIS terms.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

13. WIS Global Information System Centres (GISC's)
Major Components and Services of WIS: World Hydrological Cycle Observing System (WHYCOS)
Data and Product Users
regional Hydrological Cycle Observing Systems (HYCOSs)
National Hydrological Services (also known as WIS NC's)
And here we see the World Hydrological Cycle Observing System (WHYCOS) from a WIS perspective.
Global Data Centres (also known as WIS DCPC's)
WIS Global Information System Centres (GISC's)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

14. Major Components and Services of WIS: World Weather Watch Global Observing System (GOS)
Global Observing System of WWW (operated by NMHS's)
Data and Product Users
WMO Global Telecommunication System (GTS) and Regional
Telecommunication
Hubs (also known as WIS DCPC's)
observations (satellite and surface)
inter-comparison and validation
National Meteorological Centres (also known as WIS NC's )
Here is a cartoon showing some of the World Weather Watch Global Observing System (GOS) components described in WIS terms.
WIS Global Information System Centres (GISC's)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

15. Major Components and Services of WIS: World Climate Programme (WCP)
WIS National Centres (operated by NMHS's)
Data and Product Users
National Climate Data Management Systems
National Climate Forecast Systems
Regional Climate Centers (WIS DCPC's)
And here is the World Climate Programme (WCP)
World Climate Data Centres (WIS DCPC's)
Global Climate Forecast Producing Centres (WIS DCPC's)
WIS Global Information System Centres (GISC's)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

16. Major Components and Services of WIS: Global Terrestrial Observing System (GTOS)
Data and Product Users
Calibration / Validation
Terrestrial Ecosystems Monitoring Sites (TEMS)
GTOS Data Centres Directory
Observations
GTOS Resources Directory
This shows a WIS view of the Global Terrestrial Observing System (GTOS)
WIS Global Information System Centres (GISC's)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

17. Major Components and Services of WIS: Global Ocean Observing System (GOOS)
Data and Product Users
Observations
WMO Global Telecommunications System (GTS)
Product Generation
JCOMM Data Portals (also known as WIS DCPC's )
and here is the Global Ocean Observing System (GOOS)
IODE Ocean Portal (also s a WIS DCPC )
WIS Global Information System Centres (GISC's)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

18. Major Components and Services of WIS: Global Climate Observing System (GCOS)
GCOS Baseline and Comprehensive Networks, and Satellites
Global Observing System Information Centre [Web portal]
Data and Product Users
GCOS and related Monitoring and Analysis Centres (includes WIS DCPC's)
Here is the Global Climate Observing System (GCOS) as well.
Observations
Product Generation
WIS Global Information System Centres (GISC's)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

19. Major Components and Services of WIS: Global Earth Observations System of Systems (GEOSS)
National Centres
Data and Product Users
WIS Global Information System Centres (GISC's)
WIS Data Collection or Production Centres (DCPC's)
As I mentioned, the WMO Information System (WIS) and each of the WMO systems just shown are also registered as contributed systems to the Global Earth Observations System of Systems (GEOSS), overseen by the Group on Earth Observations (GEO).
The DAR catalogue of WIS is interoperable with the catalogs of the GEOSS Clearinghouse.
Later in this presentation, I will expand on the implications of this interoperability of catalogue systems.
Earth System Models
Other Data Sources
GEOSS Clearinghouse
Earth Observation Systems
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

20. Outline of WIS Compliance Specifications
Purpose and Authority of Specifications
Major Components and Services of WIS
Flow Diagrams amongst WIS Components
Technical Specifications of WIS Interoperable Interfaces
Now, I would like to go into further detail from a systems design perspective. This next section will present Data Flow Diagrams amongst WIS Components
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

21. Flow Diagrams amongst WIS Components: Introduction to the Data Flow Diagrams
defines how the Function carries out the transformation
source data which is transformed by the Function
Control
the result of the transformation carried out by the Function
Function
To document the Technical Specifications of interoperable interfaces within WIS, we have used a data flow model of the WIS functional architecture.
The technique used here follows the standard known as "Integration Definition for Function Modelling"(IDEF0). Some of the main features of IDEF0 are illustrated here.
The central concept of IDEF0 is that Functions transform Inputs into Outputs in accordance with the Controls and making use of the Mechanisms.
The IDEF0 standard supports "hierarchical decomposition" of both functions and data flows. That is, as one drills deeper into any part of the model, further definition is evident in the inherited functions and data flows. To the extent that decomposition is rigorous, this logical hierarchy of data flows and functions is a very useful feature.
Input
Output
Functions transform the Inputs into Outputs in accordance with the Controls and making use of the Mechanisms
Mechanism
identifies the resources/facilities that are used by the Function (e.g. humans, computers...)
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

22. Flow Diagrams amongst WIS Components: High-level WIS Functions
Here is the IDEF0 diagram showing the high-level WIS functions. I'll walk through a typical scenario to introduce these functions and their data flows. In this scenario, a user of WIS finds available WMO data relevant to his needs.
The data flow enters on the left with a "User Request", in this case an “Information Search Request”. Function A2 performs its "Assign User Role" function with this input, in accord with the applicable control, “User Role Assignment Procedure”. The output of function A2, a "User Request with Assigned Role", flows to function A3, "Maintain and Expose Catalogue of Services and Information". Function A3 performs its function and delivers “Information Search Results” to the user as a type of "Information Service".
Having identified a desired data or product using the “Information Search Results”, the user's next objective is to obtain WMO data. Again the data flow enters on the left with a "User Request", but in this case it is a “Request for Information”.
Function A4 performs its "Authorize Access to Information by Users" function with this input, in accord with the control, “Applicable Data Policy”. The output of function A4 is an "Information Access Authorization".
If the request is for recurring subscription, this output becomes input to function A3 for the purpose of updating "Dissemination Metadata".
Together with "Ad Hoc" request inputs, the function A5, "Deliver Information to Users", performs the actions for its output, "Delivered Information". This output is as another type of "Information Service".
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

23. WIS Compliance Specifications of GISC, DCPC, and NC
Flow Diagrams amongst WIS Components: VGISC ITT References WIS Functions
The Virtual GISC (VGISC) Invitation to Tender (ITT) includes by reference the WIS Functions (A1 - A6) described in the WIS Compliance Specifications  Excerpt from VGISC ITT Table of Contents:
4.1 Introduction to WIS Architectural Requirements
4.2 Function A.1 - Collect Observations, Create Products and Archive Information
4.3 Function A.2 and A4 - Authenticate and Authorize Users
4.4 Function A.3 - Maintain and Expose Catalogue of Services and Information
4.5 Function A.5 - Deliver Information to Users
4.6 Function A.6 - Manage System Performance
4.7 Function A.7 - Web Interface
The VGISC ITT includes by reference the WIS Functions (A1 - A6) described in the WIS Compliance Specifications
Here is an excerpt from the VGISC ITT Table of Contents, showing the WIS Functions A1 through A6.
The VGISC ITT created an additional function, A7, to address their WEB interface specifications.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

24. WIS Compliance Specifications of GISC, DCPC, and NC
Flow Diagrams amongst WIS Components: Discovery, Access and Retrieval Catalogue
The most visible new fuction provided by WIS will be function A3: Maintain and Expose Catalogue of Services and Information.
This is the function concerned primarily with the comprehensive Discovery, Access and Retrieval (DAR) catalogue for all of the data and information encompassed by WIS.
The DAR search service allows searchers to find data and products by searching a catalogue using subject keywords, geographic extent, or temporal range. The searcher can then choose from a list of catalogue records describing relevant items.
At this point, the user's authorization for delivery of the product would be checked against his role. WIS would then facilitate delivery through any of a broad range of online and offline options, including subscription services.
Here is a closer looks at a data flow diagram for the network services that occur at interfaces supporting the DAR facility, which is hosted by the GISCs.
I have said that the WIS Technical Specifications are focused on "interoperable interfaces". This search service is one such interface.
I would like now to look more closely at exactly how such an interface actually works.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

25. Standardized Interface Example: Information Search and Retrieval
  operation=searchRetrieve&version=1.1&   maximumRecords=100&recordSchema=XML&   query=(geo.bounds within/partial/nwse " ") and (geo.keywords any "biologic ecologic")
In this particular interface specification, WIS adopts an existing international standard, ISO This is the network service standard used by libraries worldwide for searching online catalogs, and it also used for searching geospatial metadata.
The ISO Information Search and Retrieval standard defines how to specify searches precisely, when you need accurate results. This includes latitude and longitude boundaries and scientific terms, as well as bibliographic citations. Of course, this standard can be used simply with Internet search engines. But it has the expressive power for complex data searches such as chemical formulas and the pattern-matching needed for images.
Because WIS adopted an existing international standard for catalogue searching, WIS resources can be handled easily by external systems. Also, WIS applications can easily make tools to search a wide range of additional resources.
latitude, longitude boundaries
terms, etc.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

26. Interoperable Search Example: SIMDAT
For example, here is the search facility for the SIMDAT software, which is installed in 11 countries as a WIS prototype for WIS. This facility can support the ISO standard interface, as shown in the box at the bottom of the screen.
This standard search interface adopted for the WIS DAR catalogue interface allows WIS to interoperable with most of the major systems that make geospatial resources available.
ISO 23950: query= ((geo.keywords any "ozone")and
(geo.bounds within/partial/nwse " ")and
((geo.begdate >= /isodate ) and (geo.enddate <= /isodate )))
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

27. Interoperable Search Example: Global Change Master Directory
Here is another interoperable resource: the Global Change Master Directory.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

28. Interoperable Search: Global Change Master Directory
Like the DAR catalogue of WIS, the Global Change Master Directory is searchable by keywords, geospatial extent, or time range.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

29. Interoperable Search Example: Geospatial Resources
We see a similar approach used with the EU "geoportal",
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

30. Interoperable Search Example: Geospatial Resources
and the open source UN project known as "GeoNetwork",
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

31. Interoperable Search Example: Geospatial Resources
and again in the search facility for the United States Spatial Data Infrastructure.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

32. Interoperable Search Example: Geospatial Resources
Which works much like Canada's GeoConnections search facility.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

33. Interoperable Search Example: Journal Resources
The ISO standard for searching is not limited to geospatial resources. This is the same standard used by virtually all of the world's libraries and online information services, including scientific journals.
Finding relevant scientific journal articles can be very important when users are looking to find and apply data or information resources. This interoperability between modern metadata techniques and traditional bibliographic practice is absolutely essential: NO metadata cataloger could hope to include all of the information really necessary to fully understand the details of a set of data. For example, the precise technical details of instruments and measurement techniques can be crucial to understanding the strengths and weaknesses of a data set.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

34. Interoperable Search Example: ISO 23950 and OGC CSW
<?xml version='1.0' encoding='UTF-8'?>
<csw:GetRecords xmlns=' xmlns:csw='
xmlns:ogc=' xmlns:gml=' version='2.0.2' outputFormat='text/xml; charset=UTF-8' outputSchema='
maxRecords='50' startPosition='1'>
<csw:Query>
<csw:Constraint version='1.1.0'>
<ogc:Filter>
<ogc:And>
<ogc:PropertyIsLike escapeChar='\' singleChar='?' wildCard='*'>
<ogc:PropertyName>any</ogc:PropertyName>
<ogc:Literal>ozone</ogc:Literal>
</ogc:PropertyIsLike>
<ogc:PropertyIsGreaterThanOrEqualTo>
<ogc:PropertyName>geo.timePeriodOfContent</ogc:PropertyName>
<ogc:Literal> </ogc:Literal>
</ogc:PropertyIsGreaterThanOrEqualTo>
<ogc:PropertyIsLessThanOrEqualTo>
<ogc:Literal> </ogc:Literal>
</ogc:PropertyIsLessThanOrEqualTo>
</ogc:And>
<ogc:Intersects>
<ogc:PropertyName>ows:BoundingBox</ogc:PropertyName>
<gml:Box srsName='EPSG:4326'>
<gml:coordinates>-11.95, ,58.45</gml:coordinates>
</gml:Box>
</ogc:Intersects>
</ogc:Filter>
</csw:Constraint>
</csw:Query>
</csw:GetRecords>
Interoperable Search Example: ISO and OGC CSW
operation=searchRetrieve&version=1.1& maximumRecords=50&startRecord=1& query=((geo.keywords any "ozone") and
(geo.bounds within/partial/nwse " ")and
((geo.begdate >= /isodate )and (geo.enddate <= /isodate )))
Before leaving this detailed look at the standard search service, I would like to comment on the new "Catalog Search for the WEB" (CSW) standard developed by the Open Geospatial Consortium (OGC). Support for OGC interfaces is becoming common among systems that process geospatial data, which are crucial to WIS.
Here is the SRU search I've shown before, compared to the same search using "OGC Filter Expression", one of the required OGC CSW query syntaxes.
Although these two queries may look different, the essential content of the query is exactly the same. In fact, the semantics of most CSW information elements is derived from ISO It also happens that the SRU and CSW network interfaces use very similar technologies.
Given the close alignment between CSW and SRU, the WIS Programme Office is funding development of a gateway that will be operated by the U.S.
Through this CSW-SRU gateway, any application compliant with the ISO interface used in WIS will be also compliant with the OGC CSW interface.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

35. Outline of WIS Compliance Specifications
Purpose and Authority of Specifications
Major Components and Services of WIS
Flow Diagrams amongst WIS Components
Technical Specifications of WIS Interoperable Interfaces
We have looked at what the Compliance Specifications are intended to be, and how they address the major components and services of WIS. We have also looked into the use of flow diagrams as a way to show how interoperability is achieved at interfaces, and an example of how such an interface actually works.
Now I would like to look in detail at the Technical Specifications of WIS Interoperable Interfaces.
The Technical Specifications of WIS interfaces are the authoritative part of the Compliance Specifications document.
There are fifteen WIS interface technical specifications.
The specifications are given as minimum requirements of an NC, DCPC, or GISC. Yet, any centre is welcome to implement interfaces beyond the minimum, and the functions of some DCPCs are expected to be extensive.
The interfaces should be regarded as "mandatory if applicable". In other words, if a WIS centre implements one of these interface functions, then the Technical Specification of that interface is required.
With regard to technology, an NC can arrange for a DCPC or GISC to perform functions on its behalf.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

36. Technical Specification of WIS Interfaces: Template
Applicable Standards
Communication Types
Service Level Required
Network Transports and Supporting Services
Performance Metrics
WIS Data Flow Diagrams
Use Cases
WIS Requirements
Notes
Each of the WIS Technical Specifications is described in terms of the nine topics in the template shown here:
Applicable Standards - Each Specification should require conformance to existing international standards
Communication Types - - Network interfaces can be distinguished by the roles of the end points (e.g., "terminal-host", "client server", "peer-to-peer", "broadcast"), or by how sessions are handled (e.g., "file transfer", "store-and-forward", "request-response", "publish-subscribe").
Service Level Required - the required network service level is one of three: - Dedicated bandwidth with high reliability is required for time-critical and operation-critical data and products (i.e., "real time" and "high priority" messages), such as hazard alerts; - A mix of dedicated and publicly shared network services is needed for some interfaces; - Non-dedicated shared networks such as the public Internet are sufficient in other cases.
Network Transports and Supporting Services - Requirements are specified for matters such as reliable transport and encryption.
Performance Metrics - Performance metrics should be prescribed for each Specification, such as maximum response time.
WIS Data Flow Diagrams - Each Specification references one or more Data Flow diagrams as found in Appendix A for the function served by the interface, as well as the entering and exiting data flows.
Use Cases - References for the applicable Use Cases are found in Appendix B.
Notes - This part of the Specification provides various explanatory text.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC

37. Technical Specification of WIS Interfaces: Template
Applicable Standards
Communication Types
Service Level Required
Network Transports and Supporting Services
Performance Metrics
WIS Data Flow Diagrams
Use Cases
WIS Requirements
Notes
WIS Requirements - Each Specification lists the various WIS Requirements it satisfies. These are given here as a short phrase, but they are referenced to fuller statements of WIS requirements given in Appendix C. All of these WIS Requirements are citations from authoritative WMO documents.
Certain of the WIS requirements apply across all of the Technical Specifications, and I will just read these here as overview:
- incorporate IGDDS as one component of WIS; - anticipate a virtual all hazards network for exchange of detection data and warnings; - support monitoring of the performance of WIS; - use standard service definitions for interoperable interfaces, specifying the syntax and semantics of data exchanged at the interface; - use international industry standards for protocols, hardware and software; - use off-the-shelf hardware and software; - should be cost effective and affordable, technologically sustainable and appropriate to local expertise, modular and scalable, flexible and extensible; - support different user groups and access policies, including WMO Resolutions 25 and 40; - provide data security; - provide network security; - support integration of diverse datasets; - allow WMO centres to enhance their capabilities; - evolve from successful components of existing WMO systems; - pay special attention to a smooth and coordinated transition; and, - serve all WMO and related international programmes.
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WIS Compliance Specifications of GISC, DCPC, and NC

38. WIS Compliance Specifications of GISC, DCPC, and NC
Technical Specification of WIS Interfaces: Uploading Files / the GISCs "Cache
Interface Technical Specification
Required for: NC
DCPC
GISC 1
Uploading of Metadata for Data and Products  2
Uploading of Data and Products 3
Centralization of Globally Distributed Data
The first two WIS Technical Specifications are concerned with uploading files of metadata and data. For metadata, the most relevant standard is ISO and the WMO Core Metadata Profile. For the data itself, relevant standards are found in the GTS Manual and other relevant WMO manuals.
The third interface deals with the set of WMO data and products required to be cached for 24 hours at the GISCs. Although the cache generally is required to be current across all GISCs to within 15 minutes, operation-critical data such as hazard warnings must be current to within two minutes.
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WIS Compliance Specifications of GISC, DCPC, and NC

39. WIS Compliance Specifications of GISC, DCPC, and NC
Technical Specification of WIS Interfaces: User Identification and Role Information
Interface Technical Specification
Required for: NC
DCPC
GISC 4
Maintenance of User Identification and Role Information  5
Consolidated View of Distributed Identification and Role Information 6
Authentication of a User 7
Authorization of a User Role
The next four interface specifications deal with authentication and authorization of candidate or current users of WIS.
For updating user identification and role information, we envision that WIS Centres will support both a file upload facility for "batch" updating, and an online form for changing individual identification and role entries.
Administrators of authentication and authorization at WIS Centres need to share the updated identification and role information as a resource available across WIS Centres.
To authenticate a user, client software would send an authentication request to the authentication server, along with user identification and credentials. The authentication server would check the consolidated identification and role information and then return an authentication response. That response would either confirm or deny that the identified user has provided sufficient credentials.
Authorizing the user to act in a role would be accomplished by client software sending to the authorization server an authorization request for an identified user. The authorization server would reference the consolidated identification and role information resource for WIS, and then return an authorization response. That response would contain a list of the authorized roles for the user, or would deny that the identified user has any authorized roles.
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WIS Compliance Specifications of GISC, DCPC, and NC

40. WIS Compliance Specifications of GISC, DCPC, and NC
Technical Specification of WIS Interfaces: DAR Catalogue Search and Retrieval
Interface Technical Specification
Required for: NC
DCPC
GISC 8
DAR Catalogue Search and Retrieval  9
Consolidated View of Distributed DAR Metadata Catalogues
The procedures for designation of a GISC or DCPC require that both maintain data and product catalogues, and service catalogues as well.
These two interface specifications deal with the Discovery, Access, and Retrieval Metadata Catalogue. Interface 8 faces the external world of users, while interface 9 concerns how the WIS centres accomplish a consolidated view.
Various methods can be envisioned for logically centralizing the physically distributed DAR Metadata Catalogue. One approach could be to use a transaction system for synchronizing changes among multiple copies of a distributed database, as prototyped in the SIMDAT Virtual GISC project.
At the DAR Catalogue Search and Retrieval interface, the network interface uses public or private Internet and may include encryption. Other relevant standards include the ISO Information Search and Retrieval Protocol and the WMO Core Profile of the ISO Metadata Standard.
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WIS Compliance Specifications of GISC, DCPC, and NC

41. WIS Compliance Specifications of GISC, DCPC, and NC
Technical Specification of WIS Interfaces: Dissemination Metadata / Downloading Files
Interface Technical Specification
Required for: NC
DCPC
GISC 10
Downloading Files via Dedicated Networks  11
Downloading Files via Non-dedicated Networks 12
Downloading Files via Other Methods 13
Maintenance of Dissemination Metadata 14
Consolidated View of Distributed Dissemination Metadata Catalogues
Here are listed five interfaces that deal with dissemination of data and products. WIS distinguishes the networking Service Level required, and each WIS Technical Specification is designated one of three:
Dedicated bandwidth with high reliability for time-critical and operation-critical data and products, such as hazard alerts.
A mix of dedicated and publicly shared network services, or
Non-dedicated shared networks such as the public Internet
Interface 10 addresses Downloading of Files via Dedicated Networks. This includes current distribution processes that follow the GTS Manual and other relevant WMO manuals. It can also include dissemination via WMO's IGDDS (Integrated Global Data Distribution System). IGDDS transmits data and products using satellite broadcast at radio or television frequencies.
Interface 11 is titled "Downloading Files via Non-dedicated Networks". In addition to IGDDS, this interface deals with sending data and products over public or private Internet, and may include encryption.
Maintenance of Dissemination Metadata can be accomplished with facilities for "batch" updating and an online form for changing individual entries. WIS Centres are required to communicate all changes to each physically distributed part of the logically centralized Dissemination Metadata.
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WIS Compliance Specifications of GISC, DCPC, and NC

42. WIS Compliance Specifications of GISC, DCPC, and NC
Technical Specification of WIS Interfaces: Reporting of Quality of Service
Interface Technical Specification
Required for: NC
DCPC
GISC 15
Reporting of Quality of Service 
The final interface specification concerns the Reporting of Quality of Service.
All WIS Centres have a role in monitoring the overall WIS. It is envisioned that performance reports can be generated efficiently by having each WIS Centre upload its reports to a single analysis site within a fixed time window.
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WIS Compliance Specifications of GISC, DCPC, and NC

43. WIS Compliance Specifications of GISC, DCPC, and NC
WIS Web site: Questions?
This concludes my presentation of the WIS "Compliance Specifications of GISC, DCPC, and NC".
Hopefully, there is time now for questions.
10 Jun 2008
WIS Compliance Specifications of GISC, DCPC, and NC