Supply Chain Traceability

A unique, unclonable cryptographic identity is injected into the silicon during manufacturing. This Device Identifier Composition Engine (DICE) or Physically Unclonable Function (PUF) creates a fingerprint that cannot be altered or replicated, serving as the anchor for all subsequent traceability claims. This identity is the root of the Hardware Bill of Materials (HBOM).

Every transfer of physical possession is recorded as a signed attestation. Using Remote Attestation and Platform Configuration Registers (PCRs) , each handler—from the foundry to the OSAT to the distributor—cryptographically signs a statement confirming receipt and the component's integrity. This creates an unbroken, verifiable audit trail anchored in the hardware root of trust.

Physical and logical countermeasures ensure any attempt at interception or modification is detectable. Tamper Resistance mechanisms and Secure Provisioning processes ensure that if a chip is physically probed or its firmware is altered, the cryptographic identity is invalidated. Anti-Rollback Protection prevents an attacker from loading a vulnerable, older firmware version to bypass security checks.

A cryptographically signed Hardware Bill of Materials (HBOM) is generated at each stage and verified automatically upon receipt. This structured record lists every integrated circuit and firmware component. Automated systems compare the received HBOM against the expected, signed manifest, instantly flagging any component substitution, addition, or version mismatch before the hardware is integrated into a system.

A formal, structured record listing all hardware components within a product, including integrated circuits and firmware. An HBOM serves as the inventory baseline for supply chain traceability, enabling organizations to identify vulnerable or counterfeit components. Key aspects include:

• Component-level granularity: Lists every IC, resistor, and firmware binary
• Vulnerability management: Maps known CVEs to specific hardware revisions
• Provenance tracking: Records manufacturer, lot codes, and country of origin
• Regulatory compliance: Supports Executive Order 14028 requirements for software and hardware transparency

The cryptographically secure process of injecting initial device identity, keys, and firmware into a silicon component during manufacturing. This establishes the immutable root identity that anchors the entire traceability chain. Critical elements include:

• Key injection ceremony: Secure generation and installation of unique device keys in a hardware security module (HSM)-controlled environment
• X.509 device certificates: Embedding PKI certificates that bind the physical chip to a verifiable digital identity
• One-time programmable (OTP) fuses: Burning immutable identity data directly into silicon
• Supply chain custody transfer: Each provisioning step is cryptographically signed, creating an auditable chain of custody from fab to deployment

A physical structure within a silicon chip that exploits inherent manufacturing variations to generate a unique, unclonable device fingerprint. PUFs provide the physical root of identity for traceability by creating a hardware-intrinsic key that cannot be copied or extracted. Key properties:

• SRAM PUF: Uses power-up state variations in SRAM cells as a unique fingerprint
• No key storage: The private key is regenerated on-demand and never stored in non-volatile memory
• Tamper-evident: Any physical probing or modification alters the PUF response, destroying the identity
• Anti-counterfeiting: Enables verification that a chip is genuine and not a cloned or remarked component

A hardware security standard that layers boot states to create a compound device identity, enabling secure boot, remote attestation, and cryptographic identity without requiring a discrete TPM. DICE is critical for traceability because it cryptographically binds the device identity to the firmware state. Core concepts:

• Layered identity: Each boot stage generates a new asymmetric key pair derived from the previous stage's secret and the next stage's code hash
• Compound Device Identifier (CDI): The final identity is a cryptographic combination of hardware identity and all firmware layers
• Attestation without TPM: Provides remote attestation capabilities using only the main processor's secure boot ROM
• Supply chain visibility: Any firmware tampering changes the CDI, making unauthorized modifications immediately detectable

A hierarchical security model where each stage of the boot process cryptographically validates the integrity and authenticity of the next stage before execution, anchored by an immutable Hardware Root of Trust. This is the verification backbone of supply chain traceability. Essential stages:

• Root of Trust (RoT): The first immutable code executed, typically stored in ROM, that verifies the next stage's signature
• Bootloader verification: Each subsequent bootloader validates the next before passing control
• OS kernel measurement: The final stage measures and records the operating system kernel hash into PCRs
• Attestation evidence: The complete chain of measurements provides verifiable proof that only authorized code has executed from silicon to application

A security capability, guided by NIST SP 800-193, that protects platform firmware and critical data against unauthorized modification, detects corruption, and recovers to a known good state. PFR ensures ongoing integrity throughout the component lifecycle. Key protections:

• Protection: Hardware-enforced write protections on firmware flash regions
• Detection: Continuous runtime monitoring of firmware integrity using cryptographic hash verification
• Recovery: Automatic restoration of corrupted firmware from a golden, signed recovery image
• Supply chain continuity: Ensures that a component deployed in the field maintains its verified integrity, closing the loop on traceability from manufacturing through operations