Quantum-Safe Cryptography Migration Checklist

Migrating to post-quantum cryptography is complex. This checklist gives you a concrete, trackable plan to move from awareness to a quantum-safe estate.

Phase 1 — Foundation (Now)

• [ ] Executive sponsor appointed for quantum-readiness.
• [ ] Budget allocated for discovery and migration.
• [ ] Cryptographic inventory started.
• [ ] Data classification by confidentiality lifetime completed.
• [ ] AES-256 standardised for all new data-at-rest encryption.
• [ ] Strong KDF (PBKDF2 ≥ 600k iterations, Argon2, or scrypt) mandated for password-derived keys.
• [ ] MD5, SHA-1, RC4, DES, 3DES and RSA-1024 eliminated.

Phase 2 — Discovery and Risk (0-6 months)

• [ ] Full inventory of TLS endpoints, VPNs, SSH, code signing, databases.
• [ ] Long-lived keys identified (root CAs, firmware signing, archives).
• [ ] Data with >10 year confidentiality requirement identified.
• [ ] Hardcoded algorithms and key sizes documented.
• [ ] Suppliers queried for quantum-readiness roadmaps.
• [ ] Risk register updated with quantum entries.

Phase 3 — Crypto-Agility (6-12 months)

• [ ] Algorithm choices abstracted behind interfaces in critical systems.
• [ ] Protocols and formats versioned to allow algorithm negotiation.
• [ ] Key-size assumptions removed (post-quantum keys are larger).
• [ ] CI/CD pipelines updated to test new algorithms.
• [ ] Crypto-agility validated by rotating one algorithm in a test system.

Phase 4 — Hybrid Pilot (12-18 months)

• [ ] Hybrid post-quantum TLS (X25519MLKEM768) deployed on a pilot service.
• [ ] ML-DSA code signing piloted in a non-production pipeline.
• [ ] Post-quantum VPN or SSH evaluated.
• [ ] Performance and compatibility measured and documented.
• [ ] Incident and rollback procedures tested.

Phase 5 — Critical Migration (18-36 months)

• [ ] Long-lived root CAs reissued with post-quantum or hybrid signatures.
• [ ] Firmware and software signing moved to ML-DSA / SLH-DSA.
• [ ] Hybrid TLS rolled out across all public-facing services.
• [ ] Archives and long-term storage re-encrypted under AES-256 with fresh keys.
• [ ] HSMs and key vaults upgraded to support post-quantum algorithms.

Phase 6 — Full Migration (36+ months)

• [ ] Classical-only key exchange removed where appropriate.
• [ ] Post-quantum signatures standard across the estate.
• [ ] Monitoring for new NIST parameters and standards in place.
• [ ] Crypto-agility exercised regularly (algorithm rotation drills).
• [ ] Quantum-readiness reported to the board annually.

Ongoing

• [ ] Track NIST, ENISA, NCSC, INCD guidance.
• [ ] Watch for cryptanalytic developments in post-quantum schemes.
• [ ] Re-run discovery annually as systems change.
• [ ] Update procurement requirements for quantum-safe defaults.
• [ ] Educate new developers on post-quantum standards.

Bottom Line

Print this checklist, assign owners and dates, and review it quarterly. Migration to quantum-safe cryptography is one of the largest security programmes of the decade — but it is tractable if you break it into phases and start now.