PKUn

PKUn stands for Public Key Unification Network, a theoretical framework in digital identity and cryptography that envisions interoperable public-key infrastructures across heterogeneous systems.

Concept and components: PKUn proposes a unified trust layer atop PKI and decentralized models, using interoperable key representations, a federated key registry, and standardized attestations of key provenance. A central feature is key resolution, mapping local keys to globally recognizable identities, with privacy-preserving proofs.

Architecture: The PKUn stack is described as comprising identity, trust, and resolution layers. The identity layer handles verifiable keys and metadata; the trust layer encodes cross-domain endorsements and policy semantics; the resolution layer provides lookup services to translate local keys into interoperable identifiers used across domains. The design emphasizes compatibility with decentralized identifiers and verifiable credentials.

Applications: PKUn is proposed to support cross-organizational authentication, secure Internet of Things ecosystems, and federated digital signatures across cloud services with stronger interoperability than current PKI.

Security and challenges: Potential benefits include streamlined trust across domains, but challenges include trust transitivity, revocation propagation, privacy concerns, scalability, governance, and regulatory alignment. Practical adoption would require standardization, governance models, and interoperability tests.

Relation to existing technologies: PKUn draws on PKI, the Web of Trust, and DID-based identity frameworks. As of writing, PKUn remains largely theoretical, with experimental prototypes in academic settings and industry pilots addressing feasibility and performance.