1. World Meteorological Organization (WMO) Observing and Information Systems Department
Compliance Specifications of GISCs, DCPCs, and NCs in the WMO Information System (WIS)
As you have heard, a document entitled "Compliance Specifications of GISC, DCPC, and NC" has been approved. I am the principal author of that document, and my presentation will draw from it extensively.
Presented 25 September 2008 at Joint Implementation-coordination Meeting on the GTS-WIS MTN and Meeting of the CBS Expert Team on GTS-WIS Operations and Implementation (ET-OI) by Eliot Christian

2. Authority of WIS Compliance 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 Centres (GISCs)
Data Collection or Production Centres (DCPCs)
National Centres (NCs)
Designation requires a statement of compliance with required WIS functions, compiled by the Inter-Commission Coordination Group on WIS (ICG-WIS)
The approved WIS Compliance Specifications are the authoritative source for interoperable interfaces required of WIS GISCs, DCPCs, and NCs
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)
Designation as a WIS centre requires a statement of compliance with the required WIS functions.
The WIS Compliance Specifications document, version 1.0, has been formally approved by the Inter-Commission Coordination Group on WIS (ICG-WIS). The WIS Compliance Specifications is now the authoritative source for "interoperable interfaces" required of GISCs, DCPCs, and NCs.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

3. Major Components and Services of WIS: GISCs, DCPCs, and NCs
WIS defines some distinct roles for GISCs, DCPCs, and NCs.
Existing National Meteorological Centres, as defined in the Manual on GTS, are expected to become WIS 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 hold and distribute copies of at least 24 hours of WMO data and products intended for global distribution. In addition, GISCs disseminate information from NCs and DCPCs within their area of responsibility.
Current centres
WIS Centres
NMHS NC
RSMC
DCPC
WMC
DCPC and/or GISC
RTH
RTH on MTN
Others
NC and/or DCPC
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

4. WIS Compliance Specifications of GISC, DCPC, and NC
Major Components and Services of WIS: Interoperability and WIS Networking
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).
RTH – Regional Telecommunication Hub NMC – National Meteorological Centre DCs – Data Collectors/ Custodians
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

5. 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.
Data Collection or Production Centres (DCPCs)
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

6. WIS Compliance Specifications of GISC, DCPC, and NC
Major Components and Services of WIS: Discovery, Access and Retrieval Catalogue
The most visible facility provided by WIS will be the comprehensive Discovery, Access and Retrieval catalogue for all of the data and information encompassed by WIS.
Here is a data flow diagram illustrating the network services that occur at interfaces supporting this facility, hosted by the GISCs.
A Discovery, Access and Retrieval facility should allow a user of WIS to find data and products by searching a catalogue using subject keywords, geographic extent, or temporal range. The user 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.
I have said that the WIS Technical Specifications are focused on "interoperable interfaces". The information search request is one such interface, and we can look more closely at exactly how that interface is specified in WIS.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

7. Standardized Interface Example: Information Search and Retrieval (ISO 23950)
  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 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.
latitude, longitude boundaries
terms, etc.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

8. 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
I would like to briefly note the 15 WIS Interoperable Interfaces that have been described as minimum requirements of an NC, DCPC, and GISC.
Any centre is welcome to implement interfaces beyond the minimum, and the functions of some DCPCs may be extensive. Accordingly, the interfaces should be regarded as "mandatory if applicable"-- the Technical Specification is required wherever the interface applies.
The first two 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 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.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

9. 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 interfaces deal with authentication and authorization of candidate or current users of WIS. Administrators of authentication and authorization at WIS Centres need to share the updated identification and role information as a resource available across WIS Centres. Of course, personally-identifiable credentials are kept local to the authentication service only.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

10. 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
A GISC or DCPC is required to maintain data and product catalogues, and service catalogues as well. 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.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

11. 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 the five interfaces dealing with dissemination of data and products.
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) using satellite broadcast at radio or television frequencies.
"Downloading Files via Non-dedicated Networks" may include IGDDS as well, but it mainly deals with sending data and products over public or private Internet.
Maintenance of Dissemination Metadata may be done centrally.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

12. 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.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC

13. WIS Compliance Specifications of GISC, DCPC, and NC
Questions?
This concludes my presentation of “Interoperability with the WIS".
Hopefully, there is time now for questions.
25 Mar 2008
WIS Compliance Specifications of GISC, DCPC, and NC