WIS2 Overview

WMO Information System 2.0 has been designed to meet the shortfalls of the current WIS and GTS, support the WMO’s Unified Data Policy and the Global Basic Observing Network (GBON), and meet the demand for high data volume, variety, velocity, and veracity.

WIS 2.0 uses the public internet (rather than private dedicated links as for GTS) and uses a "publish-subscribe" pattern where users subscribe to a topic to receive new data in real-time using the MQTT protocol.

Each Data Provider is required to host a WIS 2.0 node that sends WIS 2.0 data notifications and WIS 2.0 metadata notifications and enables the download of data over HTTP.


Navigation: WIS2 Global Services | WIS2 Topic Hierarchy | WIS2 Notification | WIS2 Metadata | Setting up a WIS2 Node | WIS2 Node Registration | Implementation Plan and Transition


WIS2 Global Services

Three types of Global Services are used to enable the dissemination of data in the WIS2 network:

  • Global Broker: Globally accessible MQTT Broker that re-publishes data-notifications of all WIS 2.0 Nodes. The users of WIS 2.0 will be able to access data in real-time by subscribing to a Global Broker and receiving notifications when new data are available for download from a Global Cache or from the data provider.
  • Global Discovery Catalogue: Globally accessible catalogue, hosted on HTTP, storing WIS 2.0 Discovery Metadata records. The Global Discovery Catalogue allows users to discover the available datasets on WIS 2.0 and provide information on how and where to access the data.
  • Global Cache: Globally accessible HTTP-endpoint where data classified as core can be downloaded from
WIS2-Global-Services

A Data Consumer in WIS 2.0 can discover the MQTT-endpoints for subscribing to data using Global Discovery Catalogue. Data classified as "core" by the Unified Data Policy will be available for download without access restrictions from the Global Cache. For "recommended data" a Data Consumer is required to access the WIS 2.0 of the data provider, and access restrictions may be applied.

Each global service operator has a centre-id. Guidance on assigning a centre-id of Global Services can be found here.

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WIS 2.0 Topic Hierarchy

Data Consumers subscribe to specific WIS2 topics to target the data-type they wish to receive.
 

WIS2-publish-subscribe-model

The topic structure is organized according to Annex 1 of the Unified Data Policy to make it easy to find the topic associated with the relevant data-type:

WIS2 Topic Hierarchy structure and example
 

For more information see WIS2 Topic Hierarchy (draft)

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WIS 2.0 Notification

The WIS 2.0 Notification standard defines the attributes used in the message payload of a WIS2 Notification.
A WIS 2.0 Notification contains a "canonical" link indicating the HTTP-endpoint where the data can be downloaded from :

WIS2-canonical-link-example

Data published on "origin/a/wis2/<centre-id>/data/core" can not implement access control and the canonical link should be available for download by the WIS2 Global Caches.

For data published "origin/a/wis2/<centre-id>/data/recommended" access control may be implemented. Data published on this subtopic will never be downloaded by WIS2 Global Caches.

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WIS2 Metadata

WIS 2.0 Discovery Metadata records are encoded according using the WMO Core Metadata Profile (WCMP) standard.
Data Producers are required to publish a WIS 2.0 Notification on the topic "origin/a/wis2/<centre-id>/metadata" of their WIS2-node, containing a canonical link to the WCMP2 record. The Global Discovery Catalogue is updated using the records published on this "metadata" subtopic.

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Setting up a WIS 2.0 Node

In order to setup a WIS 2.0 Node for data sharing on WIS2.0, the Data Provider needs to setup the following components to be accessible over the public internet:

  • MQTT-broker publishing WIS2 Notifications for data and metadata
  • HTTP-endpoint for downloading the data advertised in the notifications

These components may be provided by commercially developed weather data sharing solutions or can be developed as custom solutions by a Data Provider.

In order to accelerate the implementation of WIS2, WMO has enabled the development of the "WIS2-in-a-box" (wis2box) software: a Free and Open Source (FOSS) Reference Implementation of a WIS2 Node. For more information see the wis2box documentation.

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WIS2 Node Registration

Registration of a WIS2 Node must be approved by the Permanent Representative with WMO (PR) for the country or territory in which the WIS Centre resides. The National Focal Point (NFP) on WIS matters can register a WIS2 Node on behalf of the PR for an official NC or DCPC listed in the Manual on WIS (WMO-No. 1060) Volume I: WIS 1.0.

  • Request hosting a WIS2 Node via WIS National Focal Point (NFP)
  • Assign a centre-id: The centre identifier (centre-id) is an acronym as proposed by the Member and endorsed by the WMO Secretariat. (Guidance on assigning a centre-id of WIS2 Nodes can be found here).
  • Complete the WIS2 Register: The WIS NFP shall complete the WIS2 Register operated by the WMO Secretariat.
  • Provide Global Service details: The WMO Secretariat provides connection details for the Global Services (e.g. IP addresses) so that the WIS2 Node can be configured to provide the access.
  • WIS2 Node assessment: It is conducted by the principal GISC verifies that the WIS2 Node is compliant with WIS2 requirements.
  • Add new centre to WIS2: GISC notifies WMO Secretariat and confirms that this WIS2 Node can be added to WIS2
  • Communicate details to the Global Services: WMO Secretariat provides the WIS2 Node details to the Global Brokers to subscribe to the WIS2 Node.

More guidance can be found at the Guide to WIS, Vol. II. 2.6.1.1 Registration and decommissioning of a WIS2 Node

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Implementation plan and transition

For more information see WIS2 Implementation plan and GTS-to-WIS2 transition

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(Last update: 30 June 2024)