Connectivity has become a standard feature in industrial equipment and consumer products. Remote monitoring, OTA updates, and data-driven services are now part of the typical architecture of many devices.

However, this connectivity has also expanded the attack surface. Every connected device represents a potential entry point, and any vulnerability may affect not only the device itself but also the associated infrastructure.

At the same time, the regulatory framework has evolved. Standards such as ETSI EN 303 645, the new cybersecurity requirements linked to the RED Directive, and the Cyber Resilience Act are establishing clear obligations for manufacturers. Encrypting communications alone is no longer sufficient: strong device identity, effective credential protection, and software integrity are now required.

IoT security is no longer an added feature. It is a design requirement.

The Limits of Firmware-Only Security

Many current IoT architectures implement security entirely within the microcontroller: private keys are stored in internal memory, cryptographic libraries run in the main firmware, and protection mechanisms depend on MCU configurations.

From a functional perspective, this may be sufficient. The problem emerges when analyzed from an attack-resistance standpoint.

If the private key that identifies the device is stored in the system’s general memory, it becomes part of the same environment that executes the application. This means that under certain physical access scenarios or advanced manipulation techniques, that key could potentially be extracted or replicated.

When a device’s cryptographic identity can be copied, the trust model becomes weakened. The issue is not that the cryptography itself is incorrect, but that the environment where the keys are stored and used is not isolated from the rest of the system.

Current regulations do not only require encryption; they also require guarantees regarding identity protection and device integrity. In this context, a purely software-based architecture may fall short.

Secure Element: The Hardware Root of Trust

A Secure Element is a dedicated integrated circuit designed to manage and protect a system’s cryptographic assets in isolation from the main microcontroller. It acts as the hardware root of trust upon which the device’s security architecture is built.

The private key associated with the device’s identity is generated and stored inside the Secure Element. It cannot be exported. Critical operations—such as digital signatures or authentication—are executed internally within the component itself. The microcontroller requests these operations but never gains direct access to the private key.

This architectural separation fundamentally changes the risk model. Even if vulnerabilities exist in the main firmware, the device’s cryptographic identity remains protected in an independent secure environment.

The Secure Element does not replace the microcontroller; rather, it introduces a dedicated isolation layer for the elements that underpin system trust.

Alignment with Regulatory Requirements

Most IoT regulations converge around several technical principles: strong authentication, credential protection, secure communications, and software integrity.

Secure Elements facilitate compliance with these requirements in a structural way:

• They provide strong per-device identity through non-exportable cryptographic keys.
• They enhance protection of certificates and credentials against direct extraction.
• They strengthen TLS authentication by keeping the private key isolated.
• They enable cryptographic firmware verification mechanisms.
  

In addition, they significantly reduce the risk of device cloning or impersonation, simplifying the technical defense of security architectures during audits and certification processes.

A Secure Element alone does not guarantee regulatory compliance, but it provides a robust and defensible foundation.

Real Impact on Product Design

From a hardware perspective, the physical integration of a Secure Element is typically straightforward. It connects via I²C or SPI, and its footprint on the PCB is minimal. In most projects, this aspect is the easiest part.

The real work appears at the firmware integration level and in the management of device identity.

At the firmware level, the system architecture must be adapted so that critical cryptographic operations—such as authentication or signature verification—are correctly delegated to the Secure Element. This often requires redefining secure boot flows, TLS connection establishment, and certificate management.

However, the most strategic aspect is device provisioning.

Each manufactured unit must have a unique cryptographic identity that is properly registered within the backend system. Depending on the Secure Element model and the manufacturer, different approaches exist:

• Devices preconfigured at the factory with certificates generated under a controlled infrastructure.
• Internal key generation during the production process.
• Secure device personalization using manufacturer-specific tooling.
  

At this stage, it is essential to define how certificates are managed, how each identity is associated with the backend system, and how traceability is maintained throughout the product lifecycle.

Some organizations manage this infrastructure internally. Others rely on services provided by Secure Element manufacturers, which allow identity management to be outsourced while simplifying production processes without compromising the security model.

Therefore, integrating a Secure Element is not complex from a physical perspective, but it requires clear planning in firmware architecture and in the product’s identity-management strategy.

Frequently Asked Questions About Secure Elements and IoT Security

• Is a Secure Element mandatory to comply with IoT regulations?
  Not always explicitly. However, many regulations require strong credential protection, robust identity mechanisms, and resistance against tampering. In practice, a Secure Element makes it significantly easier to demonstrate compliance in a technically defensible way.
• Does a Secure Element significantly increase product cost?
  It introduces an additional unit cost, but this is typically small compared with the potential impact of a security breach, product recall, or regulatory non-compliance.
• Can a Secure Element prevent all attacks?
  No. It does not replace a secure system architecture or good firmware practices. It protects critical cryptographic assets but must be integrated as part of a broader security strategy.
• What happens if the firmware contains vulnerabilities?
  If the architecture is correctly designed, the Secure Element keeps private keys protected even if vulnerabilities exist in the main microcontroller firmware.
• Is the provisioning process complex?
  It can be if not planned from the beginning. A clear strategy for certificate management and device traceability greatly simplifies this phase.

Designing Trust Through Architecture and Manufacturing

IoT has transformed industrial equipment and consumer products into active nodes within connected infrastructures. At the same time, European regulation is raising the minimum cybersecurity requirements.

Purely software-based solutions have limitations when it comes to protecting device identity and credentials against physical attacks or advanced manipulation. The Secure Element introduces a hardware root of trust that strengthens the architecture and facilitates technical compliance with regulatory requirements.

However, security is not solved only at the conceptual design stage. It must also be consolidated during manufacturing.

IoT security is not an optional feature. In industrial products, it is part of design quality—just like electrical reliability or mechanical robustness. Integrating it from the beginning reduces risk, avoids rework, and simplifies regulatory compliance and long-term product evolution.

At Fides Electrónica, this approach is applied from the engineering and manufacturing stages. Security is treated as a technical requirement of the product, integrated into the design, validated during production, and managed with full traceability throughout its lifecycle. Device identity, provisioning, and architectural coherence are not treated as isolated elements but as part of the industrial process.

Designing trust today means integrating secure hardware, coherent firmware, and manufacturing processes aligned with regulatory requirements. And that decision must be made from the very foundation of the product.