# Hardware Root of Trust A hardware root of trust is a component or immutable starting condition whose keys, measurements, or code anchor later security decisions. ## Functions It may verify early boot code, protect cryptographic keys, measure system state, enforce rollback policy, or attest that a device began from an approved configuration. ## Boundary “Hardware-backed” does not mean infallible. Manufacturing, provisioning, key custody, firmware bugs, downgrade paths, physical access, and verification policy remain part of the trust chain. ## Relationships [[Trusted Platform Module|TPM]] · [[Secure Enclave]] · [[Android Verified Boot]] · [[Signed System Volume]] · [[Pre-OS Trust Boundary]].