Getting ready for post-quantum: the standards are finished and the deadline is 2035

What the first three standards cover

• FIPS 203: A module-lattice key encapsulation mechanism, used for key exchange — the first thing that needs to change in most estates.
• FIPS 204: A module-lattice digital signature standard for general signing.
• FIPS 205: A stateless hash-based digital signature standard, kept as a backup resting on different mathematics.

Why start now, when the machines do not exist yet

The reason is the pattern known as harvest now, decrypt later. An attacker can capture encrypted traffic today and keep it until the tools to decrypt it exist. Anything that has to stay confidential for a long time — medical records, contracts, personal data — is therefore already exposed, whatever the state of the technology that would eventually read it.

The timeline NIST has set

NIST's transition guidance deprecates quantum-vulnerable algorithms and removes them from its standards by 2035, with high-risk systems expected to move much sooner. For organisations running long-lived equipment — industrial control systems, or network hardware kept in service for a decade — that date is closer than it feels.

What can be done now without replacing anything

The first task is not swapping algorithms. It is knowing where cryptography is used at all, which is information many organisations do not currently hold.

• Inventory where cryptography is used across critical systems: in transit, at rest and for signing.
• Identify data that must stay confidential for more than ten years, since that is the group that moves first.
• Add a requirement for algorithm agility to your procurement criteria for new systems, starting now.