Matter over Thread: IoT Interoperability and Reliable Networking

Introduction

Matter is an interoperability protocol used for IoT (Internet of Things) devices. It allows IoT devices to communicate regardless of connectivity protocols such as WiFi, Bluetooth, Ethernet, or Thread.

Thread is a protocol that offers internet access similar to Wi-Fi, but with several benefits, including:

• Powerful encryption
• Low latency
• Low power consumption
• Accommodation of several hundred devices
• IPv6 mesh topology

Matter over Thread represents a significant leap forward in IoT connectivity. By combining Thread’s low power and reliable networking with Matter’s interoperability, it simplifies smart home integration. In this guide, we’ll explore its key features, advantages, and practical applications.

Architecture of Matter over Thread

In this configuration, Matter uses Thread as one of its network layers, with Thread providing Matter with a low power and secure connectivity option.

As shown in Figure 1, the Matter architecture consists of:

• Matter Bridge
• Matter Controller
• Matter Devices
• Thread Border Router
• Thread Mesh Extender
• Thread Devices (Battery Operated)

Matter over Thread

Let’s understand the functions of these modules within the Matter over Thread architecture:

• Matter Device: This device type supports the Matter protocol and interfaces with the Thread network. Examples include smart home devices like sensors, thermostats, and lights.
• Matter Bridge: As shown in the figure, the Matter Bridge connects to the Thread network using a Thread Border Router (TBR). It provides a bridge between other wireless protocols (such as Zigbee or Z-wave) and the Thread network. This enables the integration of non-Thread devices into a Thread-based smart home system. These devices can be controlled and managed by a Matter controller. The Matter Bridge functions as a translator between non-Thread devices and the Thread network.
• Thread Border Router (TBR): It functions as a gateway that connects the Thread network to the internet. It provides a secure connection to cloud-based services and allows for remote access to the Thread network. It is responsible for managing the Thread network and its devices, including the assignment of IP addresses and handling of security protocols. Examples of TBRs include EFR32MG21 from Silicon Labs, RA6M4 from Renesas, and CC1352P from Texas Instruments.
• Thread Mesh Extender: This is used to extend the range of the Thread network by creating additional “hops” for network traffic to travel through. Unlike the TBR, it doesn’t connect the Thread network to the internet or provide any cloud-based services. Examples of Thread Mesh extenders include nRF5340 from Nordic Semiconductor and STM32WB from STMicroelectronics.
• Thread Device: It usually runs on battery power and can communicate with other Thread devices in the network, forming a self-organizing and self-healing mesh network. Examples include smart sensors, door locks, and motion detectors.
• Internet Connectivity: This is an essential requirement for the Matter controller and cloud services to communicate with the TBR and other Matter devices.

Advantages of Matter over Thread

Here are some benefits of the Matter over Thread architecture:

1. Low Power Consumption: Thread technology is designed to allow devices to operate on low power. Therefore, Thread devices can run on battery for longer periods, making it suitable for Matter devices like sensors and door locks that require long battery life.
2. Security: The Matter protocol supports security features to protect the privacy and security of smart home devices and their data. Moreover, Thread also supports security features such as secure channels and rotating keys, offering additional protection against potential security threats.
3. Reliability: Thread uses a mesh network in which Thread devices function as routers and relay messages between them. This prevents a single point of failure, unlike WiFi with its central router. Due to this feature, when a device fails or goes offline, the Thread network self-heals itself.
4. Scalability: Thread can support several hundred devices on a single network, each with multiple IPv6 addresses.
5. Extended Range: The mesh network topology of Thread allows devices to act as routers, creating additional “hops” for network traffic. This is very useful in larger buildings or homes where the network may not have sufficient range to cover all the devices.
6. Interoperability: Matter over Thread devices can communicate with each other without any compatibility issues. Hence, consumers can use any devices as per their choice without worrying about their manufacturers.

Conclusion

Matter over Thread bridges the gap between reliability and interoperability in IoT. Its adoption is poised to make smart homes more efficient, connected, and user-friendly.