A Universal Framework for Claim Portability in Self-Sovereign Identity Applications

Abstract

Self-sovereign identity (SSI) provides users of the internet control over their own data by letting them store it on their own device or in a decentralized way, such as on a blockchain. The Super App is an SSI application currently under development by the Delft Blockchain Lab, but it still lacks one of the core features of SSI, which is interoperability. In SSI applications, the user will be in control over their identity when an issuer attests to it. Services can request confirmation about the identity of a user through a verifiable claim, to which the user can reply with this attestation. This research first focuses on building a claim portability framework, which means these verifiable claims and attestations can be communicated between the Super App and other applications. This framework is designed using a public key infrastructure, as that is already present in the Super App. Before sending a claim or attestation, it is signed by the sender and encrypted with the public key of the intended receiver for security purposes. The Super App currently lacks infrastructure to assign issuers of attestations, so a Trusted Issuer registry will have to be stored somewhere in the network. To contest the adoption problem that currently exists in many SSI solutions, the usability has been evaluated as it plays a significant part in adoption. For this, some mock-up user interfaces were created and evaluated by users through a survey and some suggestions were made for improvements.