A Policy-Agnostic Programming Language for the International Data Spaces

It is of utmost importance to maintain digital sovereignty in the context of Industry 4.0 and data-driven business models. As data itself becomes a valuable asset, this is a challenge that many companies have to face. This is particularly true as data sharing with third parties is a mandatory component of many modern business models. For its participants, the International Data Spaces (IDS) provide an ecosystem that supports the establishment and protection of their digital sovereignty. In this extended paper, we present the requirements in the area of usage control that have emerged from the IDS. We recapitulate the current state of the domain-specific language D∘, which has usage control mechanisms as a core functionality. We then introduce extensions to the policy system of D∘ and the language itself to meet these requirements. We demonstrate how the policy system can be extended by label-based mechanisms in order to increase the expressiveness of the policy system. These mechanisms can be used to attach metadata to data as well as other language components of D∘ and therefore allow easy tracing of data and sharing of information between language components such as policies. We introduce a mechanism to D∘ that allows to dynamically map external identifiers (like the ones used in the IDS) to those used in D∘. This allows D∘ to be combined with other usage control solutions as it facilitates the use of global identities that exceed D∘.