Applying a linked data compliant model: The usage of the Europeana Data Model by the Deutsche Digitale Bibliothek

In 2013/14 the Deutsche Digitale Bibliothek (DDB) changed its data model from the CIDOC conceptual reference model to the Europeana Data Model (EDM). This decision was taken against the background of two major mandates the DDB has to fulfill: as a portal and as a platform the DDB is providing access to digital objects from German cultural heritage and research institutions. The DDB also aims to become the German aggregator for Europeana. Using EDM as the internal DDB data model was considered the most reasonable solution to meet these challenges. The DDB uses the data model for all portal functions that require semantic links between metadata (search facets, hierarchies, links between authority files and digital objects). The application of EDM for the DDB portal created some difficulties since not all necessary classes and properties had been entirely implemented in Europeana-EDM at that time. Therefore, DDB defined a metadata model which is based on the Europeana Data Model Definition but contains additional extensions. The DDB publishes metadata under the CC0 Public Domain Dedication license in EDM-RDF/XML via an OAI-PMH interface to serve Europeana and also via an Application Programming Interface (API) for external users to develop new applications on the basis of metadata harmonized by the DDB.