WLAN is the undisputed radio network for Internet communication. For the IoT (Internet of Things), people have been searching for a long time for the perfect wireless standard that can be used across all systems. Google, Amazon, Apple and Co. have joined forces and present: Thread, probably the most versatile IoT network in the world. Even Apple HomeKit, which is otherwise so closed, is opening up to new target groups through the integration of Thread.
Thread IoT Standard: The most important facts
Thread is a new network protocol developed by the Thread Group for the IoT – practically a kind of WLAN, only more economical in energy consumption. It allows smart-home devices to communicate effectively with each other and with the control device. Although there are already some established smart-home wireless standards, Thread has a good chance of replacing them – at least in part – in the future.
That’s because Thread sets new standards in the following areas:
- Network coverage
- Energy efficiency
- Flexibility in the choice of smart home system
- Number of connected devices
- Open source and integration into already existing infrastructures.
Like WLAN, Thread is based on the universal Internet Protocol (IPv6). It does not depend on a central hub such as a bridge, unlike popular standards such as ZigBee and Z-Wave. While other systems become more error-prone the more devices are connected, it is exactly the opposite with Thread. The network becomes more and more stable as the components pass radio commands to each other. And because more and more sensors and devices will be integrated into the smart home in the future, this is a very decisive advantage.
From a technical point of view, Thread complements WLAN perfectly. Both are IP-based technologies, so they can use the same hardware. In the future, most WLAN routers will also be Thread-capable.
Will Thread become an IoT standard?
A new industry standard in IoT can only become established when industry leaders agree. And that is exactly what has happened with Thread. The alliance, founded back in 2014 by Google subsidiary nest, now includes Apple, Google, Amazon, LG, Samsung, Siemens, IKEA, D-Link, Qualcomm, Synopsys, Bosch, Somfy, DEKRA, OSRAM, Philips, Dannvoss, Miele, plus the ZigBee Alliance and EnOcean GmbH. The list of brands could hardly be more impressive, so it’s virtually a done deal that Thread will become the new IoT standard.
How does Thread’s network work?
In the smart home world, there are three different types of radio links that are needed:
- Very high-throughput radio links (WLAN, for example).
- Medium throughput wireless connections (for example, Z-Wave)
- Radio links with low and super-low data throughput and correspondingly low or super-low energy consumption (for example EnOcean).
The problem so far has been that most systems on the market specifically designed for the smart home require a radio bridge (a kind of additional router) for the radio standard used. This is because WLAN is out of the question for many use cases due to its high energy consumption.
Thread was therefore designed to transmit lower data rates, so that Thread and WLAN together cover the entire spectrum of transmission rates. This is possible because Thread covers three different data throughput rates: medium, low, and super-low.
Thread is a transport system
Thread is a pure transport system for information, so it does without the software structure. You can think of it as a freight train made up of empty flatbed cars. That is, Thread can transport (almost) anything. Thread is the substructure on which a language or a system is transported by radio. Just as you can fill an empty container with refrigerators and fruit, you can transport various systems such as CHIP, HomeKit or Weave on the Thread train.
To illustrate the advantage vividly, let’s stay with the freight train again. Without the empty flatbed wagons suitable for transporting containers, one would have had to build different wagons: Wagons for transporting cars, wagons for refrigerators and yet others for fruit. This is how smart home currently works.
It’s even more impractical, because each system needs not only different carriages, but also different tracks, i.e. different radio frequencies. And these can get in each other’s way and interfere with each other. So the old systems use multiple rail networks and different wagons. This is not practical.
Thread is more reliable and secure
Next, let’s look at cloud communication, which Thread solves advantageously. To continue with our image, think of the router as a port and the Internet as a ship sailing to the cloud. In the old systems, cars and fruit are unloaded from rail cars and repacked into shipping containers and then shipped, that is, sent to the cloud servers. For repacking, each system needs a bridge, which is a transmitter.
With Thread, everything is already in containers. Here, the containers are simply loaded from the railcar onto the ship. By not needing a bridge, a Thread network can also be connected to the Internet in different places, for example in multi-family homes or if you have two routers. If one router fails, the other one simply takes over. So you can build Thread absolutely fail-safe.
And there is another advantage when no bridge is needed. The containers don’t have to be opened at the port. They are loaded at the beginning, then locked (encrypted) and only opened again (decrypted) in the cloud. As a result, Thread’s end-to-end encryption has no vulnerabilities.
Thread, just like ZigBee, builds a mesh network
With Thread, devices support each other no matter what language they speak. This is because with Thread, all devices that are connected to a power outlet or directly to the power grid are used as range extenders (repeaters) – similar to WLAN repeaters.
This is very important because Thread is, after all, a low-energy network, just like ZigBee, which also uses mesh. And a network that uses very little energy cannot radio long distances. That’s why Thread, as a mesh network, is built like a mesh fence. Commands are passed from one transmitter to the next, similar to a WLAN mesh repeater.
In an automated household, the distances between devices are always relatively short. For example, between a Philips Hue light bulb, a motion sensor, a smart TV, all the way to a window sensor. With Thread, because every device (except battery-powered ones) is itself a radio transmitter, you achieve ideal network coverage with minimal power consumption. And the devices don’t even have to speak the same language. They only have to be languages that Thread can use as a “substructure”. And that will probably be (almost) all of them in the future.
What is the difference between Thread and ZigBee?
Even though Thread uses the same radio basis (IEEE 802.15.4.), it differs significantly from ZigBee: Thread is not a communication standard. So it does away with the software layer that identifies devices and defines functions. Thread is a pure network protocol – i.e. the substructure on which a language or software such as ZigBee or HomeKit is transported.
This makes it possible to control the same end devices, such as a motion detector, thermostat or window sensor, with both Apple’s HomePod and Google Nest. If two households using a different system were to move in together, they could continue to use all of the end devices.
This flexibility is one of the main reasons why virtually all smart home providers are currently adapting their systems for Thread or OpenThread.