We used the European interoperability framework as a starting point. We first listed the principles,
interoperability layers and the conceptual model along with the corresponding recommendations in a
Google sheet. Next, we looked at the EOSC interoperability framework, paying attention to the similarities
and differences in the recommendations within both frameworks. Then we proceeded by iteratively
discussing the recommendations and selected those considered to be applicable to services. The EOSC-IF
“provides general recommendations for achieving interoperability across services (e.g., interoperability in
authentication and authorization, interoperability in the exchange of data, interoperability for ensuring the
findability of resources)...” Here, we focused on selecting recommendations that would enable more
alignment in achieving interoperability of EOSC-related services.
In addition to the four layers of interoperability described by EIF, and consequently adopted by EOSC-IF
(technical, semantic, organizational and legal), we also considered recommendations covered under other
underlying principles (subsidiarity and proportionality, openness, transparency, reusability, technological
neutrality and data portability, user-centricity, inclusion and accessibility, security and privacy,
multilingualism, administrative simplification, preservation of information and assessment of the effectiveness and efficiency) and the conceptual model of the EIF. The goal was to focus on recommendations that would improve service interoperability across service providers, considering the diversity of providers and services themselves. Overall, we selected recommendations based on a common understanding of the recommendations’ relation to service-related concepts (e.g. service management, service architecture and design, service operations, accessibility, processing of research data). This exercise resulted in 21 recommendations.
Next, we used the selected recommendations as a basis for formulating questions intended for assessing
the services. The purpose of the questions was to convert the ideas in the recommendations into
expressions that would be comprehensible and potentially easy to answer. The questions were intended for
service providers, because they are normally responsible for the services during different phases - design,
development, production etc. We used an iterative process, during which each team member was
responsible for composing the initial questions from a subset of the recommendations. The rest of the team
then reviewed the questions and provided suggestions for improvement. In order to capture the essence of
the recommendations while minimizing loaded and run-on questions, it was appropriate to use more than
one question for some of the recommendations. As a result, we generated 35 questions out of the 21

Core interoperability principles

Generic user needs and expectations

Legal interoperability

Technical interoperability

Semantic interoperability

Conceptual model