Recently, Google/Nest, together with Samsung, ARM, Yale Security and others, announced a new standard “Thread”. Sort of. Thread is not really a new standard, but more of an education and certification program that combines a set of existing standards into a “single” package. In itself, this may sound like an oddity, but in reality, this is very much like WiFi. Similarly, WiFi is recognized as a standard, but actually, it is also a sort of “package deal” between IEEE 802.11 and IETF TCP/IP. The WiFi Alliance is not really a standard development organization, but more a… yes: education and certification body for wireless local networking.
So what is Thread? And will Thread become as successful as WiFi is today? The future will tell, but a few observations can be made.
As with WiFi, the new Thread standard combines existing standards: the IEEE 802.15.4 standard for low-power wireless data-communication and the well-known EITF IPv6 (plus added some additional less-known building blocks for routing and meshing).
What is IEEE 802.15.4? Actually it is the relatively unknown little brother of IEEE 802.11 (better known as WiFi). About a decade ago, this IEEE 802.15.4 working group spun out of IEEE 802.11 with a primary objective to build a worldwide radio networking standard for sentrollers (sensors, actuators or controllers, like thermostats, light switches, security sensors, etc.).
The reason for IEEE 802.15.4 spinning out of IEEE 802.11 was the fact that the direction of IEEE 802.11 was (and today still is) how to achieve higher data rates. IEEE 802.11 (WiFi) is for content sharing and distribution, as our appetite for bandwidth seems insatiable! However, high data rates also require a lot of power and drain batteries, and therefore the goal for IEEE 802.15.4 became to build a low-power networking standard, not focusing on high data rate, but instead on long battery life. We can afford to daily recharge the batteries of our phones, tablets or laptops, but for the hundred or so wireless sentrollers in our future smart homes, it is essential that they run on batteries for years, or even a life time! And to give a sense for the result: IEEE 802.15.4 requires in the order of 10,000 times less power than IEEE 802.11, depending on the application. This means 10 years battery life instead of hours…
With this benefit, IEEE 802.15.4 has become the low power standard for wireless networking, a sort of low-power WiFi. It uses the worldwide available 2.4 GHz band, just like WiFi. IEEE 802.15.4 uses 16 smaller channels (compared to WiFi using 3 channels), which gives IEEE 802.15.4 also the agility to stay out of the way of WiFi signals. This agility is for instance currently implemented in the IEEE 802.15.4/RF4CE standard, a standard successfully used for several years now in modern TV’s and set-top boxes, replacing infrared remote controls.
The IEEE 802.15.4 standard is also the base of ZigBee as well as used in industrial standards like Wireless Hart and ISA-100. Therefore Thread endorsing IEEE 802.15.4 is just further strengthening its position in the industry, compared to proprietary protocols as for instance Z-Wave.
The other major building block that Thread is using is IPv6. Under the responsibility of the IETF, IPv6 was developed to succeed IPv4, as IPv4 is running out of addresses, in particular in light of the arrival of the Smart Home and IoT. So, combining IEEE 802.15.4 with IPv6 is a logical step. Actually, Thread is not the first to make this step, as the ZigBee Alliance had already made this step a few years ago. Unfortunately the result never succeeded in the market, because of a variety of reasons, so it will be interesting to see what Thread will be able to make out of this. In that respect it is interesting to see that 5 out of the 7 members of the Thread Group are also member of the ZigBee Alliance. But also, the support of Google/Nest may swing the balance, or maybe the timing is just better now, where it was not a few years ago.
From its press announcement it seems that the ZigBee Alliance is open to work with Thread, as the ZigBee Alliance is the home organization for several other network layers as well, like RF4CE and Green Power. But for Thread there are also alternative options available. By the way that Thread positions itself it can be viewed as a “low-power WiFi” organization, very well fitting within the structure of the WiFi Alliance. This is all too early to tell, but with the arrival of the Smart Home and the IoT, we are in for some interesting times!