Cryptographic device identity, secure boot and signed firmware built into field controllers and smart final-control elements themselves, not bolted on at the network layer.
Post-quantum / quantum-safe cryptography for critical infrastructure
Industrial IT / OT / Critical Control Information Infrastructure
Emerging Idea
Long-range · 10+ yrs
Evidence E1 · Concept
Cryptographic algorithms designed to resist attack from a future cryptographically-relevant quantum computer, replacing the RSA/ECC-based schemes protecting today's OT communications and remote access.
Short entry. This page summarises our current placement. Full, sourced analyses are published first for the technologies closest to practical use; see the list of full analyses.
How it works
The public-key algorithms that secure most communications today, RSA and elliptic-curve cryptography, rely on mathematical problems that a sufficiently large quantum computer could solve. Post-quantum algorithms are based on different problems believed to resist both classical and quantum attack. They run on ordinary computers; no quantum hardware is involved.
In 2024 NIST published its first three post-quantum standards: FIPS 203 for key establishment and FIPS 204 and FIPS 205 for digital signatures. Stateful hash-based signature schemes, standardised earlier, are already recommended for signing firmware. Migration usually begins with hybrid operation, running a classical and a post-quantum algorithm together.
Why it matters
Data and firmware signed today with classical cryptography could be harvested now and decrypted later once quantum computing matures — a live concern for infrastructure with multi-decade asset life.
Where it fits
Industrial equipment installed now may still be in service when quantum attacks become practical, and firmware-signing keys in particular must remain trustworthy for the life of the device. The priorities are long-lived signatures, remote-access and site-to-site encryption, and any data that must stay confidential for decades. The new algorithms use larger keys and signatures, which is a real constraint on small embedded devices and low-bandwidth links.
Why we place it at the Emerging Idea stage
National standards bodies (NIST and equivalents) have finalised initial post-quantum algorithm standards; OT-specific migration guidance and product support are only just beginning. Estimated time to the Proven in Use stage: 10+ yrs. What the stages mean.
Key risk
The installed base of OT devices with embedded, unchangeable cryptography is enormous — full migration realistically runs a full asset-replacement cycle, not a software patch cycle.
Questions to ask before committing
- Do you have an inventory of where cryptography is used in your control systems, and which algorithms?
- Are new products crypto-agile, meaning algorithms can be replaced by update, or is the cryptography fixed in hardware?
- What is each key supplier's published roadmap for post-quantum support, especially for firmware signing?
Standards and terms to know
- ML-KEM
- The key-establishment algorithm standardised in FIPS 203.
- Harvest now, decrypt later
- Recording encrypted traffic today in order to decrypt it once quantum computers are available.
- Crypto-agility
- The ability to change cryptographic algorithms without replacing the product.
Related technologies
See this entry on the full maturity map · All IT/OT & CCII entries · How placements are made. Stage and time-horizon placements are editorial judgements based on public information as of October 2026, not engineering, safety or investment advice; see the Terms of Use.