> For the complete documentation index, see [llms.txt](https://frameworks.greendealdata.eu/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://frameworks.greendealdata.eu/operational-frameworks/intermediaries-and-operators/catalogue-and-data-brokerage-services.md).

# Catalogue and Data Brokerage Services

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*This section might be updated based on the latest developments in the SAGE consortium, specifically considering WP6, WP7, WP4, and the Techie group, including inputs from T3.2 on GDDS Catalogue, Marketplace and Registries,* *Task 3.4 on value-added services. Since the project runs till 2028, the final GDDS deliverable is expected to have additional information on these sections.*  
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The GDDS provides a Catalogue portal that supports dataset discovery across the ecosystem by integrating with the Federated Catalogue. It offers a unified search interface, with advanced filtering and faceted search that allow users to refine queries across multiple criteria — including restricting results to selected underlying catalogues. By exposing harmonised, standardised metadata and supporting structured navigation across federated resources, the Catalogue improves the visibility and accessibility of datasets and reduces fragmentation between catalogue services. 

On selecting a dataset, the user is directed to the Federated Catalogue dashboard, where detailed metadata can be reviewed and where access negotiation and subsequent data transfer are initiated in accordance with the GDDS governance frameworks. Access to data found through the Catalogue is therefore never automatic: discovery leads to a governed access decision, applying the access and usage conditions set under Data Sovereignty & Technical Governance. 

Through these capabilities, the Catalogue reinforces the role of intermediaries within the GDDS: it facilitates trusted data discovery, supports efficient access brokerage, and promotes interoperability across distributed data services, contributing to a more integrated and user-centric data-sharing environment. 

The technical architecture of the Catalogue, its application stack, its integration with the Federated Catalogue API, and the federated authentication that enables single sign-on across the portal and the Federated Catalogue dashboard, is specified in the Technical Framework (see [Data Value Creation Enablers — Publication and Discovery](/13-data-value-creation-enablers/publication-and-discovery.md)). This Operational Framework section describes only the service and the intermediary role it serves. 

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*Note: The portal requires a confirmed name.  (Task 3.2) refers to it as the "GDDS Central data and service catalogue"; a final portal name is to be confirmed. Owner: WP3.* 
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