The Interoperability Test Bed (ITB) is the conformance testing solution used within Simpl-Labs, the experimentation and testing portal supporting Simpl as the open source middleware for data space interoperability.

The Simpl programme is an ambitious initiative supporting the creation of the Common European Data Spaces; the data ecosystems where data providers and consumers can share data in a safe and secure manner. Funded by the European Commission, Simpl provides a middleware enabling interoperable data exchanges by means of common data standards and policies, supported by open source components that anyone can review, reuse and adapt according to their needs.

Simpl is composed of three products:

• Simpl-Open, the open source software stack that powers data spaces and other cloud-to-edge federations initiatives.
• Simpl-Live, the instances of Simpl-Open for specific data spaces, supported by feasibility studies to facilitate their deployment.
• Simpl-Labs, Simpl-Open’s playground allowing data space owners and developers to experiment with Simpl-Open and test for interoperability.

Simpl-Open is developing a Minimum Viable Product (MVP) with essential functionalities to be expanded later. This MVP and all released code by Simpl-Open, is open source and available at https://code.europa.eu/simpl. Over time, the ultimate goal is to hand over Simpl to the community, so that community users and service providers can lead Simpl’s maintenance and further evolution.

For Simpl-Labs in particular, the first step has been a feasibility study launched in January 2024 to detail its requirements and technical architecture, and to provide a working proof-of-concept. The feasibility study is in its final stage and set to complete by early 2025. Following this, Simpl-Labs will be fully implemented and accessible to all users in the programme’s upcoming phases.

As part of the development of Simpl, and in particular the feasibility study for Simpl-Labs, the Interoperability Test Bed was selected for the implementation of Simpl-Labs’ conformance testing features. The Test Bed has been used for several years in Commission-driven cross-border solutions, providing a self-service platform for software vendors and Member State administrators to test their IT solutions. Such conformance testing would now be applied to data space owners and component developers, seeking to measure their implementations against the Simpl-Open specifications.

Using the Test Bed in this case involves a novel deployment approach adapted for the multi-tenant architecture of Simpl-Labs. Instead of a central service for all users, each Simpl-Labs tenant has an embedded Test Bed instance, with tests automatically configured based on user-selected options in the Simpl-Labs portal. Test sessions are subsequently managed from the Simpl-Labs interface, triggering calls through the Test Bed’s API to launch tests, receive updates and produce reports. This approach allows an uninterrupted user experience, fully integrated with other Simpl-Labs features, while ensuring each user’s testing is isolated from others.

Moving past the Simpl-Labs proof-of-concept, users will be able to export and use their testing setups outside the Simpl-Labs portal. Based on the Test Bed’s sandbox feature, users are expected to be able to install locally a preconfigured testing package and execute tests on-premise, connecting to local services and including conformance tests in continuous integration pipelines. Extensions are also foreseen for the testing scope, expanding the focus from individual component implementations, to cover entire data spaces, testing incoming and outgoing data flows at a data space’s boundaries.

All development resources for the Simpl-Labs proof-of-concept, including the Portal and Test Bed configuration, are published on its public repository on code.europa.eu. While the feasibility study is being wrapped up, the next important step will be public procurement launched by the European Commission’s DG for Communications Networks, Content and Technology in 2025, for the further development of Simpl-Labs beyond its proof-of-concept.

An important upcoming milestone for Simpl will be the 1st Simpl Annual Community Event, to be held on January 30th at Autoworld in Brussels. Available also to stream online, this will be the perfect opportunity to see Simpl in action and, for those keen on the conformance testing track, see how the Test Bed is used within the Simpl-Labs proof-of-concept. In the meantime, information and news on Simpl can be found on the Simpl programme website.

Regarding the Test Bed itself, general details on its services and use cases can be found in the Interoperable Europe Portal, with its value proposition being a good starting point for newcomers. To receive updates on Test Bed news and releases remember to subscribe to the Test Bed on the Portal, and to follow Interoperable Europe’s updates on X and LinkedIn.

The Interoperability Test Bed is a service provided by the European Commission’s DIGIT, offering conformance testing and validation solutions in support of IT systems’ cross-border interoperability.