Von Ralf Keuper
Unter den vielen Studien, die sich mit den Einsatzmöglichkeiten der Blockchain-Technologie für die Verwaltung digitaler Identitäten beschäftigen, ragt Towards Self-Sovereign Identity using Blockchain Technology für mich deutlich hervor. Darin stellen die Autoren auch eine eigene Lösung bzw. das entsprechende Design sowie ein Fallbeispiel/Proof of Concept (KYC) der Rabobank vor.
Um auf Basis der Blockchain tragfähige Geschäftsmodelle zu entwickeln, reichen private (permissioned) Blockchains nach Ansicht der Autoren nicht aus:
Blockchain technology should allow any number of entities to do transactions with each other, without the need to entirely trust each other. Permissioned blockchains create dependencies on trusted third parties in the infrastructure itself. This creates an unfair advantage and heightens entry barriers for new entrants.
Although permissioned blockchains can be linked as sidechains to public and permissioned blockchains to handle more sensitive data, the connecting chain should be public. This allows any entity to connect to the system without having to pay licensing fees.
It will be assumed that the ideal DIMS will be built on a public blockchain, where identities are established at the edge of the network and not in the network itself.
Das Vertrauensproblem werde mit der Blockchain nicht wirklich, d.h. final gelöst:
It is important to understand that this network of decentralized trust works best for solving the double spending problem, since it is proven that certain currency has been ”made”. For claims this is different. The network does not know why a claim has been made by a certain entity. The only thing that is non-reputable is that a certain claim is made by a certain entity on a certain moment in time.
Insofern bleiben Institutionen wichtig, welche im Hintergrund für die eindeutige Verifizierung sorgen.