Securing Embedded Systems with the Infineon SLB9645TT2 Hardware Trust Anchor

The proliferation of connected embedded devices, from industrial controllers to medical equipment, has escalated the need for robust security. Software-based security measures alone are increasingly vulnerable to sophisticated attacks. Integrating a dedicated hardware trust anchor, such as the Infineon SLB9645TT2 Trusted Platform Module (TPM), provides an immutable root of trust that is fundamental to building secure embedded architectures.

A hardware trust anchor is a dedicated cryptographic processor designed to securely store keys and perform sensitive operations in isolation from the main system CPU. This isolation is critical because it protects cryptographic assets from software-based attacks that might compromise the operating system or application code. The SLB9645TT2 is a mature and widely adopted TPM 1.2 compliant device that delivers this essential functionality in a compact package.

The core value of the SLB9645TT2 lies in its secure key generation and storage capabilities. Unlike software-stored keys, which reside in vulnerable system memory, private keys never leave the confines of the TPM's hardened hardware. All cryptographic operations, such as RSA signing and key wrapping, are executed within the chip itself. This design ensures that even if the host microcontroller is compromised, the fundamental cryptographic keys remain protected against extraction.

This capability enables several critical security functions for embedded systems. Secure Boot is a primary application, where the TPM can verify the digital signature of each piece of boot code—from the initial bootloader to the operating system—before it is executed. This process creates a chain of trust, preventing the device from running tampered or malicious firmware. Furthermore, the TPM’s built-in Hardware Random Number Generator (RNG) is crucial for creating strong cryptographic keys and nonces, which are far superior to software-generated alternatives.

Beyond Secure Boot, the SLB9645TT2 facilitates platform integrity measurement. It can store hashes of critical software components in its shielded locations. During operation, these values can be reported to a remote server for attestation, providing cryptographic proof of the system's health and integrity. This allows network operators to verify that a remote device has not been altered before granting it network access or sensitive data.

For data protection, the TPM can be used to bind or seal data to a specific platform state. Binding encrypts data using a TPM-stored key, meaning it can only be decrypted by that same TPM. Sealing takes this a step further by tying the decryption of data to a specific software state (as measured by the Platform Configuration Registers - PCRs). This ensures sensitive configuration data or logs are only accessible when the device is in a known-good state.

Despite being a TPM 1.2 device, the SLB9645TT2 remains highly relevant for a vast array of embedded applications where its feature set provides a powerful and cost-effective security solution. It offers a proven, hardware-enforced foundation for trust that is resistant to remote software exploits.

ICGOODFIND: The Infineon SLB9645TT2 TPM provides an essential hardware-based root of trust for embedded systems, delivering unparalleled security for key storage, secure boot, device attestation, and data protection against software-level threats.

Keywords: Hardware Security Module, Secure Boot, Cryptographic Key Storage, Device Attestation, Root of Trust.