Reference

The vocabulary, without the hedging.

Post-quantum cryptography arrives with a dense vocabulary and a lot of confident-sounding summaries. These are the definitions we use internally, with a note on why each one matters.

A 1 term

Agentic identity: The identity and authorization model for autonomous AI agents: what the agent is, what it may do, on whose behalf, and how its actions are attributed and revoked.; Why Agents given long-lived API keys create over-privileged identities that cannot be attributed or revoked quickly.; Agentic identity services

C 7 terms

Certificate lifecycle automation: Issuance, renewal, rotation, and revocation of certificates without manual steps, typically using ACME or a CA integration.; Why Manual lifecycle is the most common cause of expiry outages and the biggest obstacle to reissuing a fleet for a new algorithm.; PKI modernization
CMVP: The Cryptographic Module Validation Program, the joint NIST and Canadian Centre for Cyber Security effort that validates modules against FIPS 140-3.; Why Validation timing is a real constraint on product roadmaps, not a paperwork detail.
CNSA 2.0: The Commercial National Security Algorithm Suite 2.0, published by the NSA. It mandates ML-KEM and ML-DSA, requires LMS or XMSS for signing, and excludes SLH-DSA.; Why New national security system acquisitions are expected to be CNSA 2.0-compliant by default from January 1, 2027.; Federal and defense
Code signing: Digitally signing software and firmware so recipients can verify origin and integrity. Migration to PQC signatures is a distinct, harder problem than TLS migration.; Why Signatures are long-lived and embedded in fielded systems, which makes signing one of the earliest practical deadlines.
Crypto agility: The ability to change algorithms, keys, and certificate parameters across a fleet quickly, with testing and rollback.; Why Every migration deadline is easier if the cost of change is low. Agility is the capability that makes repeated migration survivable.; Migration and agility
Cryptographic bill of materials (CBOM): A machine-readable inventory of the cryptographic assets in a system, including algorithms, keys, certificates, protocols, and the components that implement them.; Why It is the system of record for migration, and federal guidance on its minimum elements is expected around March 2027.; CBOM explained
Cryptographically relevant quantum computer (CRQC): A quantum computer capable of breaking current public-key cryptography at the key sizes in use. Its arrival date is uncertain; the migration lead time is not short.; Why You do not need to predict the date to plan. You need to know which data must remain secret past it.

D 1 term

Data lifespan classification: Tagging data by how long it must remain confidential, so cryptographic risk can be prioritized by exposure rather than by asset visibility.; Why It is the field that turns a CBOM from a list into a migration order.; Risk prioritization

F 1 term

FIPS 140-3: The current standard for validating cryptographic modules. FIPS 140-2 certificates moved to the historical list on September 21, 2026.; Why PQC modules must clear the same validation queue, which has averaged 18 months or more.; Read FIPS 140-3

H 3 terms

Harvest now, decrypt later (HNDL): An attack pattern in which encrypted traffic is captured and stored today, to be decrypted once a cryptographically relevant quantum computer exists.; Why It makes the risk immediate for long-lived data, regardless of when the quantum computer arrives.; How this applies to financial services
HQC: Hamming Quasi-Cyclic, selected by NIST in March 2025 as a backup key-encapsulation mechanism to diversify beyond lattice assumptions. A standard is in development.; Why It signals that algorithm diversity matters, and that crypto agility is a requirement rather than a nice-to-have.
Hybrid key exchange: Running a classical key exchange and a post-quantum KEM together, so the session is protected if either remains secure.; Why It is the pragmatic first step for TLS migration, preserving interoperability while reducing quantum risk.

L 1 term

LMS / XMSS: Stateful hash-based signature schemes standardized in NIST SP 800-208. CNSA 2.0 requires them for software and firmware signing in some contexts.; Why They carry state-management requirements that ordinary signing pipelines do not handle, which makes them an implementation risk.; Software and supply chain

M 2 terms

ML-DSA (FIPS 204): Module-Lattice-Based Digital Signature Algorithm, derived from CRYSTALS-Dilithium. The general-purpose post-quantum signature standard.; Why It is the default choice for certificate and code signing migration, and is approved in CNSA 2.0.; Read FIPS 204
ML-KEM (FIPS 203): Module-Lattice-Based Key-Encapsulation Mechanism, derived from CRYSTALS-Kyber. The standardized algorithm for post-quantum key establishment.; Why It replaces RSA key transport and elliptic-curve Diffie-Hellman in TLS and other protocols.; Read FIPS 203

N 2 terms

NIST IR 8547: NIST’s transition plan for post-quantum cryptography, proposing deprecation of classical public-key algorithms after 2030 and disallowance after 2035.; Why It is still an initial public draft, but it shapes planning across federal systems and their suppliers.; Read the draft
Non-human identity (NHI): A digital identity for a workload, service, device, or agent rather than a person: service accounts, workload certificates, API clients, and AI agents.; Why Non-human identities usually outnumber humans and are the least inventoried, which makes them a migration liability.; IAM and non-human identity

P 1 term

Post-quantum cryptography (PQC): Public-key algorithms designed to resist attack by both classical and quantum computers. NIST standardized the first three in August 2024: ML-KEM for key establishment, and ML-DSA and SLH-DSA for signatures.; Why These algorithms replace RSA and elliptic-curve cryptography, which a sufficiently large quantum computer could break.; See the standards timeline

Q 2 terms

QKD vs PQC: Quantum key distribution uses quantum physics to exchange keys over dedicated hardware. PQC is software cryptography that runs on existing systems.; Why QKD is not a replacement for PQC in general enterprise use. Treating them as interchangeable leads to bad architecture decisions.
Quantum-vulnerable: Cryptography whose security depends on the hardness of factoring or discrete logarithms — RSA, ECDSA, EdDSA, finite-field Diffie-Hellman, and elliptic-curve Diffie-Hellman.; Why Symmetric algorithms and hashes are weakened but not broken by quantum attack; the migration effort is concentrated in public-key cryptography.

S 2 terms

SBOM vs CBOM: An SBOM lists software components and dependencies. A CBOM lists cryptographic assets. They are complementary: an SBOM tells you which library you ship, a CBOM tells you which algorithms it uses.; Why Most quantum-vulnerable cryptography arrives through software dependencies, so the two artifacts are usually built together.
SLH-DSA (FIPS 205): Stateless Hash-Based Digital Signature Algorithm, derived from SPHINCS+. A conservative signature standard whose security rests on hash functions rather than lattices.; Why It is a hedge against lattice cryptanalysis, but it is not approved for use in national security systems under CNSA 2.0.; Read FIPS 205

W 1 term

Workload identity: Cryptographically issued, short-lived identity for a workload, commonly implemented with SPIFFE/SPIRE or platform-native mechanisms such as cloud IAM roles for service accounts.; Why It replaces static secrets and gives every agent and service an attributable, revocable identity.

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