Quantum-Safe Digital Identity: Soulbound Tokens

Architecture

Identity That Cannot Be Stolen or Transferred

Traditional digital identity binds credentials to private keys. Keys can be stolen, shared, or lost. H33 binds credentials to the person through FHE-encrypted biometrics — creating true soulbound identity.

Soulbound

Biometric-Bound Tokens

Credentials are cryptographically bound to FHE-encrypted biometric templates. Verification requires a live biometric match performed entirely in ciphertext space. The credential cannot be transferred because it is tied to the person, not to a key pair. Even a compromised server cannot extract the biometric binding.

ZK Disclosure

Selective Attribute Proofs

Prove you are over 18 without revealing your birthdate. Prove you hold a medical license without exposing your license number. H33 generates ZK-STARK attribute proofs in 2.0 microseconds. The verifier learns only that the condition is satisfied — nothing more. SHA3-256 based, post-quantum secure, no trusted setup.

DID-Ready

W3C Verifiable Credentials

H33 credentials are compatible with the W3C Verifiable Credentials data model. Issue credentials as JSON-LD documents signed with Dilithium instead of Ed25519. Resolve identities through standard DID methods. The cryptographic layer is post-quantum; the data model is standards-compliant.

Revocable

Cryptographic Revocation

Issuers revoke credentials via cryptographic accumulators — no need to contact the holder or maintain a centralized revocation list. Verifiers check revocation status inside the ZK proof itself. The revocation check reveals nothing about other credentials or revocation reasons.

Verification Flow

Three Steps, Zero Data Exposure

From credential presentation to cryptographic attestation — the entire flow runs on encrypted data.

Step 1

Present & Capture

The holder submits their Dilithium-signed credential and a live biometric capture. Both are encrypted client-side before transmission.

Step 2

FHE Biometric Match

H33 performs inner-product matching on FHE ciphertexts. The biometric template never leaves encryption. Match completes in ~937µs for a 32-user batch.

Step 3

Attest & Prove

Dilithium signature verified. ZK-STARK attestation proof generated. The verifier receives a post-quantum proof of identity — no plaintext exposed.

Developer Experience

Verify Identity in One API Call

Post-quantum credential verification with biometric binding and selective disclosure.

            
            H33 — Quantum-Safe Identity Verification
        

// Verify a credential with biometric binding + selective disclosure
const result = await h33.verifyCredential({
  credential: signedCredential,       // Dilithium-signed VC
  biometric: liveCapture,              // FHE-encrypted template
  selectiveDisclosure: [
    { attribute: 'age', condition: 'gte', value: 18 },
    { attribute: 'jurisdiction', condition: 'eq', value: 'US' }
  ],
  securityLevel: 'h33-128'
});

// result.verified         → true (biometric match + signature valid)
// result.disclosureProof  → ZK-STARK proof (age ≥ 18 & jurisdiction = US)
// result.attestation      → Dilithium-signed attestation
// result.revocationCheck  → valid (accumulator proof)
//
// Biometric NEVER decrypted. Full credential NEVER exposed.
// Verifier learns only: age ≥ 18 and jurisdiction = US.

FAQ

Frequently Asked Questions

What is quantum-safe digital identity?

Quantum-safe digital identity uses post-quantum cryptographic algorithms to issue, sign, and verify identity credentials. Traditional identity systems rely on RSA or ECDSA signatures that will be broken by quantum computers. H33 uses ML-DSA (Dilithium) signatures and lattice-based encryption so that credentials issued today remain unforgeable even against future quantum attacks.

What are soulbound tokens and how does H33 implement them?

Soulbound tokens (SBTs) are non-transferable digital credentials permanently bound to an identity. H33 implements soulbound identity by binding credentials to FHE-encrypted biometric templates. The credential cannot be transferred because verification requires a biometric match performed entirely in encrypted space. No private key can be shared or stolen — the binding is to the person, not to a key.

How does selective disclosure work with H33 credentials?

H33 uses zero-knowledge attribute proofs to enable selective disclosure. A credential holder can prove specific attributes (such as “over 18” or “licensed physician”) without revealing the full credential. The verifier receives a ZK-STARK proof that the attribute satisfies a condition, but learns nothing else about the credential holder’s data. The proof is generated in approximately 2.0 microseconds.

How does H33 compare to W3C DIDs and SSI frameworks?

W3C Decentralized Identifiers (DIDs) and Self-Sovereign Identity (SSI) frameworks define standards for identity documents and resolution. H33 provides the cryptographic layer underneath. You can use H33 to issue W3C-compatible verifiable credentials where the signatures are Dilithium (post-quantum) instead of Ed25519, and where the holder binding is FHE biometric rather than a transferable private key. H33 is complementary to DID standards, not a replacement.

What is the credential verification flow?

The verification flow has three steps: (1) The holder submits their credential and a live biometric capture. (2) H33 performs FHE biometric matching to confirm the holder is the credential subject — the biometric never leaves encryption. (3) H33 verifies the Dilithium signature on the credential and returns a ZK-STARK attestation proof. The entire flow completes in under 1.2 milliseconds for a batch of 32 credential verifications.

Can H33 identity credentials be revoked?

Yes. H33 supports credential revocation via cryptographic accumulators. Issuers can revoke credentials without contacting the holder, and verifiers can check revocation status as part of the standard verification call. The revocation check is included in the ZK proof, so verifiers learn only that the credential is valid and not revoked — they do not learn when or why other credentials were revoked.

Which H33 product owns quantum-safe identity?

This capability aligns to H33-Key, whose owned role is secret-use control — letting an agent or human use a credential or signing key without the raw secret being exposed or transferred. Binding the credential to the person (FHE biometric) rather than to a stealable key is exactly that: the credential can be used without ever being handed over. This is distinct from a password manager (which stores secrets) and a vault (which manages storage and distribution at rest) — H33-Key controls the moment of use.

Does quantum-safe identity govern the decision or render the verdict?

No. Controlling how a credential is used without exposing it is not governing the decision made with it (that is Agent-008), rendering an independent verdict (that is Verification), recording the operations over time (that is HATS), producing the portable evidence primitive (that is H33-74), or preserving who holds which authority (that is Authority Center). H33-Key holds and controls secret use; the other layers govern, verify, record, produce, and preserve around it.

Owned by H33-Key

Quantum-safe identity is a supporting expression of H33-Key, the secret-use layer: it lets a credential or signing key be used without the raw secret being exposed or transferred. That is why binding an identity to an FHE-encrypted biometric — instead of to a stealable private key — belongs here. It is not a password manager (storage) and not a vault (at-rest lifecycle); it controls the moment of use. And holding/controlling a secret is not governing the decision (Agent-008), rendering the verdict (Verification), recording operations (HATS), producing the portable evidence (H33-74), or preserving who holds which authority (Authority Center).

Post-quantum cryptography protects identity; it does not confer authority. Identity answers who or what the subject is; authority answers what that subject is permitted to do — under which delegation, at what time, and with what evidence. Making the identity binding quantum-safe strengthens who can be proven; it does not by itself grant legitimate authority. What a proven subject may do is governed by Agent-008 and preserved by Authority Center.

Routing: use H33-Key to let an agent or person use a credential/secret without exposing it. Use Agent-008 to govern the decision the agent makes under that identity. Use Verification for the independent verdict on a produced attestation. Note: FALCON / FN-DSA referenced here is FIPS 206 (draft).

Quantum-Safe Digital Identity Infrastructure