Reference architecture for @SignOfficial (Money, ID, Capital) and how Sign Protocol + TokenTable compose across public/private rails.
Purpose
This page defines a reference architecture for S.I.G.N. deployments. It is written to be:
implementation-neutral (works with different sovereign constraints),
operator-friendly (clear roles and trust boundaries),
audit-ready (explicit evidence artifacts),
integration-ready (legacy rails + standards).
Audience
Sovereign operators (central bank infra, GovTech platform teams)
System integrators (banks/PSPs/telcos, identity vendors)
Builders (wallets, program operators, auditors)
Architectural invariants
S.I.G.N. is designed around five invariants:
Controllable privacy
private to the public,
auditable to lawful authorities,
minimal disclosure by default.
National performance
built for millions of users, multi-operator workflows, strict SLAs.
Sovereign control
key custody, upgrades, emergency controls, and oversight remain under sovereign governance.
Interoperability
standards-aligned identity (VC/DID),
standards-aware payments (ISO 20022),
compatibility with public + private rails.
Inspection-ready evidence
every critical action emits durable evidence:
who authorized what
under which authority
when
based on which identity/eligibility proof
with what rule version