Beyond Holder Binding

A Proposition Hierarchy for Presenter Binding in Digital Credentials

抄録

Verifiers of digital credentials must decide whether the person presenting a credential can be treated as the individual whose identity was confirmed at issuance, yet mechanisms such as Holder Binding and wallet attestation each cover only a fragment of this decision. We define this decision target as Presenter Binding and model it as a hierarchy of propositions: a top-level proposition — the current presenter can be treated as identical to that applicant — decomposed into issuance-time and presentation-time branches yielding twelve leaf propositions. Mapping OID4VCI, OID4VP, HAIP, the EUDI Wallet ARF, and the W3C Confidence Methods draft onto the hierarchy shows that the three protocols explicitly address seven of the twelve leaf propositions, while the remaining five —
applicant identification, correctness of the subject and identity claims, and the legitimacy of the wallet controller at issuance and presentation — depend on issuer operations, wallet certification, and
scheme policy. The model gives verifiers, issuers, and scheme operators a common language for stating which linkages a use case requires and what must be implemented to establish them.