REFERENCE
Glossary of secure-voice and post-quantum terms
A working vocabulary for engineers, procurement teams, and decision-makers in sovereign cybersecurity.
- Post-Quantum Cryptography (PQC)
- Cryptographic algorithms believed to be secure against attacks by quantum computers.
- ML-KEM
- Module-Lattice Key-Encapsulation Mechanism (formerly Kyber), standardised by NIST as FIPS 203.
- ML-DSA
- Module-Lattice Digital Signature Algorithm (formerly Dilithium), standardised by NIST as FIPS 204.
- AES-GCM
- AES in Galois/Counter Mode — authenticated encryption with associated data (AEAD), 256-bit keys.
- Trusted Execution Environment (TEE)
- Isolated processing environment inside a CPU where code and data are protected from the rest of the OS.
- ARM TrustZone-M
- Hardware security extension for Cortex-M microcontrollers that splits the chip into Secure and Non-Secure worlds.
- Secure Element
- Tamper-resistant chip that securely stores cryptographic keys and executes sensitive operations.
- DMA (Direct Memory Access)
- Hardware feature that lets peripherals transfer data to/from memory without CPU involvement; can be locked to specific bus masters.
- Hardware Security Module (HSM)
- Dedicated cryptographic appliance that generates, stores, and uses keys without ever exposing them to software.
- BYOK (Bring Your Own Key)
- Pattern where the customer holds the master key and the vendor only handles opaque encrypted material.
- FIPS 140-3
- US federal standard for cryptographic modules; defines four security levels with hardware-tamper requirements at L3 and L4.
- Common Criteria EAL
- Evaluation Assurance Level (1–7) under ISO/IEC 15408 measuring rigour of security evaluation.
- NATO Restricted
- NATO classification level for non-sensitive material whose disclosure would be disadvantageous; many crypto products target this baseline.
- EU Restricted
- European Union classification analogous to NATO Restricted, used by EU institutions.
- NIS2 Directive
- EU Directive 2022/2555 raising cybersecurity requirements for essential and important entities across critical sectors.
- EU Cyber Resilience Act (CRA)
- EU regulation imposing cybersecurity requirements on products with digital elements throughout their lifecycle.
- Air-Gap
- Physical or logical isolation that prevents a system from being reached over any network; the strongest perimeter defence.
- Side-Channel Attack
- Attack that exploits physical leakage (timing, power, EM emanation) rather than mathematical weakness of an algorithm.
- Harvest-Now-Decrypt-Later
- Adversary strategy of recording encrypted traffic today so it can be decrypted once quantum computers exist.
- Q-Day
- Hypothetical day when a cryptographically-relevant quantum computer breaks classical public-key cryptography.
- Deepfake
- Synthetic audio or video generated by machine-learning models to impersonate a person convincingly.
- MEMS Microphone
- Microelectromechanical system microphone — the digital MEMS sensor used in most modern earbuds and phones.
- Anti-Tamper
- Hardware and firmware countermeasures that detect or resist physical attempts to extract secrets from a device.