A Collaborative Approach to Metadata Interoperability

This contribution presents a joint collaboration between PID4NFDI, TS4NFDI, and the electronic lab notebook provider RSpace to support interoperable research workflows within the National Research Data Infrastructure (NFDI). It demonstrates how early, structured capture of high-quality metadata and persistent identifiers (PIDs) in ELNs, combined with shared reference schemas and centrally governed terminology services, can reduce redundant effort and improve metadata consistency and data lineage across the research lifecycle [1].

The presentation outlines the complementary roles of the partners. PID4NFDI provides coordination and architectural framing for PID integration and metadata alignment across infrastructures. TS4NFDI provides centralized access to various terminology services via a harmonized API Gateway and a  mapping infrastructure to ensure consistent, machine-actionable use of metadata terms. RSpace integrates these components into everyday research workflows, enabling structured metadata and PID capture at the point of data creation.

The collaboration establishes a shared interoperability layer spanning terminology management, schema alignment, and ELN integration. Entity mappings are used to curate, version, and publish mappings between the DataCite metadata schema and target schemas such as schema.org and DCAT, in line with recommendations from the NFDI Metadata Task Force. These mappings are maintained in Cocoda [2] with explicit provenance and versioning, supporting transparent reuse and controlled evolution.

In parallel, DataCite metadata properties and controlled vocabularies are made available via the TIB Terminology Service as part of a collaborative effort between PID4NFDI and TS4NFDI. This integration provides a canonical, machine-actionable representation of DataCite terms that can be accessed via the Terminology Service Suite widgets [3] and the TS4NFDI API Gateway [4].These services are integrated into RSpace ELN workflows, where selected DataCite properties and vocabularies are made available through embedded widgets. This enables structured metadata capture at the point of data creation, reduces free-text entry, and supports the export of interoperable ELN records aligned with NFDI-endorsed metadata standards.

Overall, the collaboration establishes a reusable, machine-actionable metadata layer based on shared terminology lookup, cross-schema mappings as a single source of truth, and clear service integration patterns. The proof of concept illustrates how PID4NFDI and TS4NFDI can work with ELN and DMP providers to enable interoperable research workflows and inform future NFDI-wide implementations.

References:

1] El-Gebali, S. (2024). Concepts for metadata interoperability, harmonization and technical integration of PID infrastructure (1.0). Zenodo. https://doi.org/10.5281/zenodo.14506138

2] coli-conc - Cocoda. (2025). Coli-Conc.gbv.de. https://coli-conc.gbv.de/cocoda 

3] Terminology Service Suite. (2025). Base4nfdi.de. https://terminology.services.base4nfdi.de/tss/comp/latest/

4] TS4NFDI Api Gateway. (2025). Base4nfdi.de. https://terminology.services.base4nfdi.de/api-gateway/swagger-ui/index.html