The European Blockchain services infrastructure (EBSI) aims to provide digital services to the EU’s member states as well as Lichtenstein and Norway for cross-border public services. EBSI utilizes distributed ledger technology (DLT) hosted by a network of nodes across Europe. Within EBSI, several use-case groups have been identified, such as Self-Sovereign Identity (SSI), diplomas, notarization, and trusted data sharing, describing the current service capabilities. The European Self-Sovereign Identity Framework (ESSIF) represents the SSI use-group supporting Europe to implement the SSI model enabling the users to control their own identity data. The diplomas use-case group focuses on trustworthy and easy to verify educational credentials in digital form. Trusted data sharing utilizes the Blockchain technology for secure data sharing of, e.g., VAT numbers across customs and tax authorities in the EU. In contrast, the notarisation use-case group utilizes Blockchain technology to create trusted digital audit logs used to prove properties such as authenticity and data integrity.
EBSI4Austria is a CEF funded project that will focus on hosting the Austrian EBSI node and supporting Austrian stakeholders to participate in EBSI. Besides the two participating universities, namely Graz University of Technology and Vienna University of Economics, is the third stakeholder a company viz. Danube Tech with a strong know-how in SSI and related technologies and standardization bodies. In particular, the project will cover three main parts where; the first part focuses on the operation of the Austrian EBSI node, including the setup, maintenance, and connectivity tests. The second part focuses on designing and implementing a solution architecture covering the diploma use case based on SSI and utilizing the EBSI ledger. In this part, the universities will use and extend their existing IT infrastructure in order to connect and interact with the EBSI node as well as to issue educational diplomas based on the EBSI specification. Finally, the third part covers not only the training activities within the consortium and to third parties such as private and public stakeholders but also the dissemination activities such as reporting to the EBSI community, the publication of a case study, and results.
The results of our project are presented in a blog post Blog Post stating EBSI4Austria’s Results and can also be found on GitHub https://github.com/danubetech/ebsi4austria-examples.
Following, we present the user story, which is realized within the EBSI4Austria project.
Figure 1 illustrates the user story that is covered in our project. A student studying at the Graz University of Technology is finishing her bachelor’s program. TU Graz issues her diploma credential stating her bachelor’s degree, which the student stores in her wallet. Next, she wants to apply for a master’s program at the Vienna University of Economics and Business; thus, she presents her bachelor’s diploma credential. After successfully finishing her master’s program at WU Vienna, the university issues her master’s diploma credential to the student. The student is very ambitious; therefore, she applies for a Ph.D. position at the Berlin Institute of Technology by presenting her diplomas. All involved parties utilize the EBSI blockchain network to verify if the issuing universities are trusted issuers.
In order to implement our EBSI4Austria project, we used similar technologies as many other Self-Sovereign Identity (SSI) initiatives, i.e., based on building blocks such as Decentralized Identifiers (DIDs) and Verifiable Credentials (VCs).
We created two DIDs on the EBSI blockchain for the two universities, as follows:
- Test DID for TU Graz: did:ebsi:zuoS6VfnmNLduF2dynhsjBU
- Test DID for WU Vienna: did:ebsi:z23EQVGi5so9sBwytv6nMXMo
In addition, we registered them in EBSI’s Trusted Issuer Registry (TIR).
We also designed Verifiable Credentials to model digital versions of university diplomas. We implemented them using different credential and proof formats to accommodate changing requirements and guidelines in the EBSI specifications throughout the year. See here for some examples in different formats:
- Example Diploma by TU Graz
- Example Diploma by WU Wien
- Paper version (in German)
- Paper version (in English)
We also designed our own (experimental) JSON-LD context in order to be able to work with Linked Data Proofs (see essif-schemas-vc-2020-v1.jsonld). In our opinion, it would be preferable if JSON-LD contexts were provided by EBSI to all member states instead of having to do this separately for each EBSI pilot project.
We use the following technologies in our project:
- Universal Resolver –> For resolving DIDs.
- Universal Registrar –> For creating DIDs.
- Universal Issuer –> For issuing VCs.
- Universal Verifier –> For verifying VCs.
- SSI Java Libraries
- ld-signatures-java – For Linked Data Signatures.
- verifiable-credentials-java – For Verifiable Credentials.
This project has received funding from the European Union’s CEF programme with action No 2020-AT-IA-0072 under grant AGREEMENT No INEA/CEF/ICT/A2020/2271545. This document reflects the view of EBSI4Austria’s participants. INEA shall not be held responsible for any use that may be made of the information it contains.