Sovereign Digital Identity

Abstract

National digital identity systems sit at the intersection of every other layer in this series: they are the trust anchor for CBDC payment rails (SDIS-09), the authentication layer for sovereign cloud administration (SDIS-02), and one of the highest-value targets for the threat models discussed in SDIS-07 and SDIS-08. This paper surveys the architectural choices facing a national eID or digital wallet program — centralized versus federated versus decentralized (self-sovereign) identity models. It traces the historical evolution of digital identity architecture, uses the EU’s eIDAS 2.0 and its Digital Identity Wallet as a detailed case study alongside eleven further case studies, and specifies a reference architecture for verifiable credential issuance, presentation, and revocation that balances user privacy against the state’s need for fraud prevention and auditability. It closes with an implementation roadmap, a glossary, and a self-assessment checklist.