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4 FUNCTIONS OF WIS

4.1 Roles in and Review of WIS Functions

4.1.1 Roles in and review of WIS functions are given in Manual on WIS 4.1.

4.1.2 Each of the relevant user requirements processes across WMO should link into the WIS user requirements process. For instance, observing program needs should be incorporated into WIS requirements through linkage with the Rolling Review of Requirements (RRR) process in the Manual of the Global Observing System (WMO No. 544).

4.1.3 Current WIS User Requirements are described in a technical document available at http://www.wmo.int/pages/prog/www/WIS/documents/WIS-RRR.doc .

4.2 List of WIS Functions

WIS Centres collectively support the major WIS functions as described in Manual on WIS 4.2. The required standard interfaces to these functions are described in Manual on WIS 5, WIS Technical Specifications.

4.3 Functional Architecture of WIS

The Functional Architecture of WIS is provided as supplementary guidance for WIS Centres in a technical document available at http://www.wmo.int/pages/prog/www/WIS/documents/WIS-FuncArch.doc . As shown in that document, the following list provides one possible method for decomposing the required major WIS functions into more detailed functions.

A1 Collect Observations, Generate Products, Create Metadata and Archive Information
A11 Collect, Generate and Archive National Information & Create Metadata
A111 Collect National Observations
A112 Check Meteorological Content of Products and Observations
A113 Archive
A114 Generate National Products
A115 Generate Metadata
A116 Unpack Information
A117 Verify Correct Telecommunication Attributes of Information
A12 Collect, Generate and Archive Regional, Programme-related and Specialised Information & Create Metadata
A121 Collect Regional, Specialised and Programme-related Observations
A122 Check Meteorological Content of Observations
A123 Archive
A124 Generate Regional, Specialised and Programme-related Products
A125 Generate Metadata
A126 Unpack Information
A127 Verify Correct Telecommunication Attributes of Information
A13 Collect and Cache Global Information
A131 Unpack Information
A132 Associate Information with DAR Metadata
A133 Verify Correct Communication Attributes of Information
A134 Maintain and make available Cache of Global Information for 24 Hours
A2 Assign User Role
A3 Maintain and Expose Catalogue of Services and Information
A31 Search DAR Metadata Catalogue
A32 Maintain and Expose Consolidated DAR Metadata Catalogue
A33 Maintain Dissemination Metadata Catalogue in Accordance with Authorised Subscriptions
A4 Authorise Access to Information by Users
A5 Deliver Information to Users (Internal and External)
A51 Schedule and Control Activities
A511 Derive Time-driven (synchronous) activity schedule and list of event-driven (asynchronous) activities
A512 Monitor for Events
A513 Resolve any activity scheduling conflicts, reflecting relative service priorities
A52 Package Information for Delivery
A53 Deliver Information
A6 Manage System Performance
A61 Non Real-time Performance Monitoring
A611 Analyse Traffic Trends
A612 Analyse Performance Against Requirements and SLAs
A62 Real-time Performance Monitoring
A621 Real-time Monitoring of Telecommunication Network
A622 Real-time Monitoring of the Application Content

4.4 Data Flow among WIS Functions

4.4.1 The Functional Architecture of WIS (noted in 4.3 above) models data flow among required WIS functions and illustrative subordinate functions. The model uses Integration Definition for Function Modelling (IDEF0), a data flow diagramming technique that illustrates interrelationships between system components, at levels ranging from very general processes to specific technology interfaces.

4.4.2 Figure 2 (below) presents an IDEF0 functional decomposition of the major WIS functions, labelled A1 through A6. Data flows inherit between levels of the diagrams and are labelled as I1, I2, I3 for inputs and O1, O2 for outputs.

4.5 Functional Requirements of a GISC

4.5.1 General
There are no general recommendations in addition to the statements in Manual on WIS 4.5.

4.6 Functional Requirements of a DCPC

4.6.1 General
There are no general recommendations in addition to the statements in Manual on WIS 4.6.

4.7 Functional Requirements of an NC

4.7.1 General
There are no general recommendations in addition to the statements in Manual on WIS 4.7.