/glossary
Glossary
Short, precise definitions of security hardware terms: FIDO2, TPM, HSM, secure elements, write blockers, JTAG and more.
- FIDO2
- The FIDO Alliance and W3C standard for phishing-resistant, public-key authentication, made of the WebAuthn browser API and the CTAP device protocol.
- FIPS 140-3
- The U.S. and Canadian standard for validating cryptographic modules, run by the NIST CMVP, with four security levels from software-only to high physical assurance.
- HSM (Hardware Security Module)
- A tamper-responsive device that generates, stores and uses cryptographic keys inside a certified boundary, used for PKI, code signing, payments and key management.
- JTAG
- The IEEE 1149.1 test access port used for boundary-scan testing and, in practice, for low-level debugging and programming of processors.
- Passkey
- A FIDO2 discoverable credential used to sign in without a password, either bound to one device or synced across devices by a platform account.
- PCR (Platform Configuration Register)
- A TPM register that can only be extended with hashes, recording the sequence of firmware, bootloader and configuration measurements during boot.
- PKCS#11
- The Cryptoki standard API for talking to hardware security modules, smart cards and tokens, now maintained by OASIS.
- SDR (Software-Defined Radio)
- A radio whose tuning hardware digitizes a slice of spectrum so that demodulation and decoding are performed in software.
- Secure element
- A tamper-resistant chip, derived from smart-card technology, that stores keys and performs cryptographic operations while resisting physical and side-channel attacks.
- TPM (Trusted Platform Module)
- A standardized security processor that stores keys, records boot measurements in PCRs, seals secrets to platform state and signs attestation quotes.
- UART
- A simple asynchronous serial interface, often left on embedded boards as a boot and debug console.
- WebAuthn
- The W3C Web Authentication API that lets websites register and authenticate users with public-key credentials held by an authenticator.
- Write blocker
- A hardware or software device that lets an examiner read a storage device while preventing any command that could modify it.