Result description
The Blue-Cloud Metadata Broker is one of the technical service components of the Blue-Cloud Data Discovery & Access Service (DD&AS). It is based upon the DAB service as developed and managed by CNR-IIA. This middleware harvests metadata at collection level from each of the Blue Data Infrastructures (BDIs), using their web services. The Discovery and Access Broker (DAB) service transforms the harvested XML files from each of the BDIs into a common ISO Blue-Cloud collection profile, which is encoded using the recent ISO 19115-3:2016 XML profile, providing a common denominator of metadata fields, which is then published by the DAB service by means of a Blue-Cloud OGC CSW – ISO v. 2.0.2 service. The provided common denominator allows users to discover data sets in each BDI in a common way at collection level. This service is fully dynamic and currently runs every week to provide the latest index of the data collections.
More technical background information can be found in the Blue-Cloud architecture document.
Problem addressed
Different stakeholder groups in marine science use various metadata schemes and ontologies. The Metadata Broker service supports configuring and providing a common denominator for the metadata schema at data collection level, while in Blue-Cloud 2026 the Data Discovery & Access Service (DD&AS) will be expanded with also a Semantic Broker service, using ontologies, in order to provide common vocabulary terms in the metadata output.Also, it will be explored how the common denominator of metadata fields and their semantic support could be expanded in cooperation with the BDIs.
