AFFIXIO
Post-quantum
Post-quantum signatures for agent verification
Agent authorisation artefacts that must remain valid for years should not depend on classical-only signatures. AffixIO uses ML-DSA-65 (FIPS 204) for signed allow or deny outcomes on eligibility and payment permission proofs.
Definition
Post-quantum agent signatures use ML-DSA-65 to sign verification outcomes so agent authorisation evidence remains checkable against future cryptanalytic advances.
Field note. Classical agent signing keys signed today may be breakable tomorrow. Plan ML-DSA-65 migration on verify paths now.
ML-DSA-65 in the AffixIO path
Signed allow or deny outcomes use ML-DSA-65. Merkle audit references sit beside those signatures so evidence packs stay coherent.
Use the PQC verifier tool and post-quantum attestation field note when validating integrations.
Migration posture
Treat PQC as default for new agent gates. Classical-only paths create a future rewrite. Procurement teams increasingly ask for FIPS 204 alignment in verification infrastructure.
This is algorithm choice for AffixIO outcomes, not a claim about every system in your estate.
Rollout notes for post-quantum agent signatures
Place issue at consent or policy satisfaction, then verify at the first external boundary. Deny should return a stable code for support. Allow should attach Merkle metadata to the record your finance or ops team already stores.
When WAN is unreliable, run local verify with cached keys and sync Merkle inclusion later. Offline QR and edge agents use the same spent-proof rules as online gates.
Gate failure
Long-lived evidence, classical algorithms
Disputes, audits, and regulated retention can outlast the comfortable lifetime of classical signatures. Agent commerce makes that gap wider.
Harvest now, decrypt later
Captured classical signatures may be forgeable later if algorithms fall.
Mixed estates
Partners still ask which PQC algorithm you actually ship.
Tooling gaps
Teams need verifiers and field notes, not slogans.
Recovery proof
Post-quantum signatures for long-lived agent credentials
Agent verification keys with years of validity need migration to NIST-approved post-quantum schemes before harvest-now-decrypt-later risk compounds. ML-DSA-65 proofs integrate with existing verify endpoints.
Confirm algorithm
ML-DSA-65 on AffixIO signed outcomes.
Validate with tools
PQC verifier and sandbox proofs.
Update evidence packs
Include algorithm identifiers for auditors.
Retire classical-only gates
For new agent authorisation paths.
Risk review
Readiness checks for post-quantum agent signatures
- Document ML-DSA-65 in architecture reviews.
- Run PQC verifier against sample proofs.
- Align retention schedules with signature lifetime assumptions.
- Brief procurement with the PQC field note.
- Avoid classical-only for multi-year agent evidence.
Platform FAQ
Questions on post-quantum agent signatures
Which algorithm?
ML-DSA-65, NIST FIPS 204.
Is Merkle post-quantum?
Merkle structures inherit strength from the hash and the signed leaves. AffixIO signs outcomes with ML-DSA-65.
Do merchants need special hardware?
Verify via API or SDK. Hardware needs depend on your deployment, not a special merchant HSM mandate from AffixIO.
Where is the field note?
/field-notes/post-quantum-attestation-guide
Paired pages
Pages that support post-quantum agent signatures
Infrastructure
More infrastructure briefs
Bench post-quantum agent signatures
Run ML-DSA-65 issue and verify in sandbox, then plan cutover on your agent credential lifecycle.