Post-quantum cryptography migration is the multi-year process of moving an organization’s systems from quantum-vulnerable algorithms (RSA and elliptic-curve cryptography) to quantum-resistant ones such as ML-KEM and ML-DSA, through structured discovery, planning, testing, and phased rollout.
PQC migration replaces quantum-vulnerable algorithms with quantum-resistant ones across an organization. It is a multi-year program that starts with a cryptographic inventory, prioritizes by risk, and rolls out in phases, often in hybrid mode. Targets are ML-KEM for key exchange and ML-DSA or SLH-DSA for signatures, while AES-256 stays. The goal is a crypto-agile, quantum-ready estate.
Key Takeaways
- PQC migration moves systems from RSA and ECC to quantum-resistant algorithms.
- It is a multi-year program, driven by Shor’s algorithm and harvest-now, decrypt-later.
- The first step is always a cryptographic inventory; you cannot migrate what you cannot see.
- Targets are ML-KEM (key exchange) and ML-DSA or SLH-DSA (signatures); AES-256 stays.
- Hybrid deployment eases the transition, and crypto-agility is the end goal.
What is PQC Migration?
Post-quantum cryptography migration is the multi-year program of replacing quantum-vulnerable algorithms with quantum-resistant ones across an organization. Because cryptography is everywhere, in certificates, protocols, applications, and devices, migration is a structured effort built on visibility, prioritization, and phased change rather than a single upgrade.
Why Migrate Now
The driver is the combination of Shor’s algorithm, which would let a quantum computer break RSA and elliptic-curve cryptography, and the harvest-now, decrypt-later threat, where data captured today is decrypted once quantum hardware matures. Migration takes years, so starting now is what protects long-lived data. Sector mandates reinforce the timeline: US CNSA 2.0 requires quantum-resistant algorithms for national security systems, with NSM-10 targeting a quantum-resistant federal estate by 2035.
The 9-phase Migration Roadmap
Encryption Consulting structures PQC migration into nine phases that move from visibility to a maintained quantum-ready state.
- Discover: Build a cryptographic inventory (CBOM) of every algorithm, key, certificate, and protocol.
- Assess risk: Rank systems by exposure, prioritizing long-lived sensitive data.
- Define strategy: Choose target algorithms and a hybrid approach for the transition.
- Establish governance: Set a cryptographic policy and ownership for the program.
- Remediate architecture: Remove hard-coded cryptography and centralize key and certificate management for crypto-agility.
- Test: Pilot post-quantum and hybrid algorithms in non-production environments.
- Deploy in phases: Roll out to production gradually, often starting in hybrid mode.
- Monitor: Track progress against target algorithms and watch for issues.
- Maintain: Keep the inventory current and adapt as standards and threats evolve.
Target Algorithms
Migrate key establishment to ML-KEM and signatures to ML-DSA or SLH-DSA, while keeping AES-256 for symmetric encryption. Use hybrid certificates during the transition so systems stay compatible and secure.
Crypto-Agility is the Goal
Migration is not a one-time event. Standards will continue to evolve, so the destination is a crypto-agile estate where algorithms can be changed again with minimal disruption, sustained by ongoing cryptographic posture management.
How Encryption Consulting Helps
Encryption Consulting’s PQC Advisory delivers this nine-phase roadmap end to end, from cryptographic inventory with CBOM Secure to hybrid deployment on HSM-as-a-Service. Backed by ISO/IEC 27001:2022 and SOC 2 certified practices.
Frequently Asked Questions
What is post-quantum cryptography migration?
PQC migration is the process of moving an organization’s systems from quantum-vulnerable algorithms (RSA and elliptic-curve cryptography) to quantum-resistant ones such as ML-KEM and ML-DSA. Because cryptography is embedded throughout modern systems, migration is a multi-year program of discovery, planning, testing, and phased rollout, not a single switch.
How long does PQC migration take?
For most organizations it is a multi-year effort, because cryptography is woven into applications, certificates, protocols, and devices. The exact timeline depends on the size and complexity of the estate. US guidance under NSM-10 targets a quantum-resistant federal estate by 2035, and many organizations align their own plans to similar horizons.
What is the first step in PQC migration?
The first step is building a cryptographic inventory. You cannot migrate cryptography you cannot see, so discovery of every algorithm, key, certificate, and protocol comes before any algorithm change. The inventory lets you assess risk and prioritize which systems to migrate first, usually those protecting long-lived sensitive data.
What is hybrid mode in PQC migration?
Hybrid mode combines a classical algorithm with a post-quantum one so a connection or certificate stays secure even if one algorithm has an unexpected weakness, and remains compatible with systems that do not yet support PQC. Hybrid deployment, including hybrid certificates, is the common transition approach before moving to post-quantum algorithms alone.
Which algorithms should we migrate to?
For key establishment, ML-KEM (FIPS 203); for digital signatures, ML-DSA (FIPS 204) or SLH-DSA (FIPS 205). Symmetric encryption such as AES-256 generally stays. The right targets and parameter sets depend on your security requirements and any sector mandates such as CNSA 2.0, which requires quantum-resistant algorithms for national security systems.
Plan Your PQC Migration
Ready to start a structured migration to quantum-safe cryptography? Talk to an Encryption Consulting PQC advisor, or begin with CBOM Secure.