IoT Security - Zign 100

The number of connected devices, machines, sensors, or simply things are linked with each other over open communication networks on the internet of things (IoT) has exploded. Processes are remotely monitored through networks of smart devices. And every device represents a potential entry point for malicious intrusion – into the device itself, or the network to which it’s connected. These new security threats pose technology challenges in securing and stabilizing such large systems. In such an environment, secure device identity is an essential requirement for clone-resistant operational security.

The Intrinsic ID Zign® 100 API enables IoT developers to generate unique device identities, secure cryptographic keys, and random values. It enables easy and collision-free identification of billions of devices from different vendors. Zign 100 can also be integrated as a hardware-based trust anchor for Mbed TLS, OpenSSL, wolfSSL, and other libraries, extending the chain of trust beyond just a single device. Because it is a software-based solution, Zign is the only hardware entropy source currently available that doesn’t have to be loaded at silicon fabrication.

Security Based on SRAM PUF

Zign 100 uses the inherently random start-up values of SRAM as a PUF from which a device-unique identity and root key is generated. The root key is never stored and is only available (in volatile memory) when needed. This means the key is never present in persistent memory – even when the chip is powered down – which raises the security significantly and eliminates the need for OTP or other secure memory.

A potentially unlimited number of keys can be derived from the root key by using the NIST-compliant key-derivation function. Zign 100 also offers random values, generated by a NIST 800-90A/B-compliant random number generator and a unique device identity for each device. All Zign features are accessed by the host software via the API.

Operating Ranges

SRAM PUF responses have been qualified for use with the Zign X00 series in a wide range of operational environments, over years of field operation:

• All major fabs from 0.35 μm to 5 nm
• Temperature range from -55°C to 150°C [-67°F to 300°F]
• Voltage supply variation +/- 20%
• Lifetime > 25 years

Zign 100 is delivered as a library compiled for a specific target chip, along with API specifications and a user manual. The solution is available in off-the-shelf configurations with size ranging between 6.8 kB and 7.9 kB.