EOSC IF interoperability guideline: access to content via PID

An important aspect of Open Science is the possibility to re-use existing research products (e.g. research data), deposited in repositories and accessible via their persistent identifiers (e.g. handle, doi, ark). However, there is no standard way a service can access the actual content behind persistent identifiers, as these typically resolve to the landing pages of the research products. The lack of standard for accessing the actual content identified by persistent identifiers makes the automatic consumption of research products hardly implementable and, when possible, limited to the persistent identifiers issued by a specific repository (e.g. the first prototype of the EGI Data Transfer Service integrated in the EOSC EXPLORE portal supported only DOIs from Zenodo). The EOSC Future Working Group on Research Product Publishing proposes the adoption of the Publication Boundary Pattern of the SignPosting protocol and recomends it for inclusion as interoperability guideline in the EOSC IF.