Author:
Neeraj Kumar Product Marketing Manager, and Hema Deepak, Senior product marketing manager, Infineon
Date
04/28/2025
PDF
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Figure 1: Near field communication (NFC) and I2C can work together to overcome limitation to current approaches to device configuration and security
Secured communication with industrial devices such as sensors, actuators, and remote controllers is paramount for smart factory managers who wish to leverage machine learning (ML) and artificial intelligence (AI) to enhance production efficiency. It is equally important for them to verify that their equipment and components are genuine. With the proliferation of the Industrial Internet of Things (IIoT), factory managers face the challenge of manually configuring a multitude of devices to connect to factory networks while providing robust security to prevent vulnerabilities to cyber-attacks that could compromise sensitive process data or halt production entirely. This article reviews the limitations of current approaches used and introduces a novel solution that brings together near field communication (NFC) and I2C to bridge the communications gap.
Limitations of Current Device Configuration Techniques
The pairing and configuration of industrial devices typically involve following instructions on a graphical display and providing inputs through a series of buttons and dials. This process can be quite laborious, particularly as it requires understanding the configuration requirements for various equipment types, each with its own interface and menu options.
For machine and equipment manufacturers, this method also has the disadvantage of increasing costs due to the need to include a display and manual controls for device configuration. These additions not only increase the bill of materials (BoM) but also necessitate a larger device form factor to accommodate a readable display and controls that can be operated easily. The IIoT also comes with a risk of lapse in security which can increase the risk of unauthorised access and data breaches, and compromise the integrity and reliability of the system.
The capability to authenticate machines and equipment connecting to their networks is particularly crucial for factory managers. This is to prevent the introduction of counterfeit devices that could be preloaded with malware or other harmful features. Such devices may pose a threat to the reputation of equipment manufacturers and can be able to compromise the safe operation of the factory.
Streamlining Design with Contactless Communication
With over a billion NFC-enabled smartphones and native support from mobile operating systems such as iOS and Android, NFC technology has seen widespread adoption. This has led to the extensive use of NFC tags in various commercial and consumer applications.
I2C, or Inter-Integrated Circuit, is a serial communication protocol that connects multiple electronic components on a single communications bus. It can support configurations with multiple controllers and targets and allows for communication at various data transfer rates.
The advantages of combining these two technologies to create an NFC-I2C bridge tag are that it can enable smooth data transfer between an NFC-enabled smartphone (or reader) and the microcontroller unit (MCU) in an IIoT device.
For industrial equipment manufacturers, one of the key benefits of this integration is the facilitation of 'headless' designs, which are devices without displays or manual controls, leading to significant space and cost savings due to smaller form factors. This type of bridge can also help implement access control measures, taking care that only authorised personnel can configure or activate a device.
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Figure 2: The integration of IIC and NFC technologies will allow smaller and cheaper device designs without the need for displays or manual controls
Secured IIoT device activation and configuration
Infineon’s NFC-I2C bridge tag, called OPTIGA Authenticate NBT, is designed for secured contactless device authentication and configuration, enabling communication between an NFC Type 4 Tag interface and an I2C connected host MCU at rates from 106kbit/s to 848kbit/s. The supported I2C modes include standard mode (100kHz), fast mode (400kHz), and fast mode plus (1MHz). The highest communication rate facilitates ultra-fast data exchange and a seamless user experience for demanding applications. In conjunction with the MCU, it establishes an authenticated communication channel for device activation and configuration.
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Figure 3: The OPTIGA Authenticate NBT enables secured contactless device authentication and configuration
The tag has multiple security options, courtesy of Infineon’s advanced TEGRION hardware, which offers robust protection against reverse engineering with features like Integrity Guard 32. It features an 8KB non-volatile memory (NVM) file system to support large data volumes and flexible password-based file management. Additionally, device authentication is supported through asymmetric cryptography (NIST P-256) with a public key infrastructure (PKI) and chip unique certificates as well as AES-128 based symmetric cryptography through dynamic URL generation for online CMAC verification. This allows users to tailor their security settings, including updating certificates and AES and ECC keys. The hardware is also certified to Common Criteria Level EAL 6+(high).
The device can be powered from an NFC reader through an antenna connected to its contactless interface pads or from an external power supply. It features an integrated I2C target interface and an interrupt request (IRQ) for data exchange with host systems.
OPTIGA Authenticate NBT has an NFC Forum Type 4 Tag certified application and NFC-to-I2C bridge functionality. The tag supports open standards and comes with host software library packages and reference example codes for quick and flexible application development. It comes in a compact USON8 package, which, combined with a high on-chip tuning capacitance, allows for a small and optimised antenna designs.
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Figure 4: The OPTIGA Authenticate NBT Development Kit allows quick and simple evaluation of OPTIGA Authenticate NBT using the reference use cases available through GitHub
Conclusion
Configuring industrial automation equipment has traditionally been time-consuming and difficult, typically requiring the use of displays, knobs and pushbuttons. This approach has resulted in devices being unnecessarily large and not always properly secured against threats from intruders.
Recognising these shortcomings, Infineon brought together two proven technologies to create a high-performance NFC-I2C bridge tag. By adopting this technology, design engineers can overcome common obstacles associated with device configuration and security, leading to more streamlined and secured industrial systems
The tag technology is versatile and can be applied to a range of industrial use cases, including device pairing, configuration, activation, and data logging. It enables engineers to authenticate devices without needing a physical interface, configure and activate devices quickly and securely, and log operations and sensor data of device for analysis and maintenance purposes.
