The Application Layer
The Application Layer essentially is the collection of commands and expected results of devices (“things”) communicating with each other. It is the most complex layer, because it covers so many different devices in so many different applications over such a wide range.
To understand the battle at the Application Layer, instead of looking horizontally, we need to take a vertical view of the Battlefield graphic to understand what is going on in this space.
The most mature contender in this space is the ZigBee Standard’s so-called Cluster Library. In the new ZigBee 3.0 version, the Cluster library has become completely integrated including the so called application profiles of Home Automation and Light Link, supplemented by Green Power for ultra-low power (e.g. battery-less) applications and ZRC for ultra-low latency applications, as required for Remote Controls. This cluster library is very complete and is also tightly integrated with the Network/Transport Layer and below. ZigBee offers well developed security and ease of installation features, and by far the largest installed base today.
Apple HomeKit is an important contender. Because Home Kit is proprietary Apple technology, it is not really a true open standard. Nevertheless, because of its strong market presence and “following”, Apple Home Kit is developing a clear market presence with applications built on top of WiFi and Bluetooth, for networking and low power wearables. Because Home Kit is not currently integrated with IEEE 802.15 it does not support low power networking, but that can change in the future if Bluetooth is successful in developing networking capabilities, or if Apple decides to implement Home Kit in top of IEEE 802.15.4.
The third player in this Application Layer is the Open Interconnect Consortium driven by Intel, but currently also others companies like Cisco and Samsung. The most recent to appear, this group have expressed priority for WiFi and Bluetooth as well.
The final contributor is the AllSeen Alliance, under the umbrella of the Unix Foundation. Their work originally began as the AllJoyn activity under Qualcomm, but after realizing that the market is too large, too diversified and too dependent on the development of a total eco-system - and that pulling this off alone would not be possible – they donated all the previous work done to the AllSeen Alliance. However, Qualcomm still chairs the AllSeen Alliance.
You may note there is quite an overlap in membership between these contenders, even to the point that not only is the market confused, but many of the participating companies are as well.
April 2015 – ZigBee and Thread Are Coming Together
In April 2015, the ZigBee Alliance and the Thread Alliance announced that they are working together to integrate the ZigBee Cluster Library on top of the Thread networking stack. A lot of work still has to be done in this area to make this happen, but this is a move into the right direction, simplifying the battlefield by reducing the number of competing networking and application layers.
May 2015 – Google Announces Brillo and Weave
At the end of May, the Google involvement got a bit more complicated. The ZigBee over Thread announcement seemed to be a very positive step on the road to standard convergence, but then Google announced Brillo (an Application Framework) and Weave (an IoT Application Layer). Both are scheduled to be available later this year (Q3/Q4). Although information is still sparse, instead of moving the industry forward, it clearly adds even more complexity to the standards picture.
What is the consequence of this double announcement?
Google announces Brillo and Weave, adding even more options to the IoT standards forecast
From an Application Framework perspective, Brillo is the fourth candidate thrown into the ring: next to Apple (Home Kit), Intel (IoTivity) and Qualcomm (AllSeen). But more specifically, Brillo appears to be Google Android’s answer to Apple’s IOS-centric HomeKit. In a way this is understandable, as both Apple (IOS) and Google (Android) are the big players in the smart phone space, and the smart phone is destined to become the dashboard and/or the gateway to many smart home, wearables and other IoT applications.
So, from that perspective Brillo (when it becomes available) and HomeKit might be able to exist side by side for some time to come, just like Android and IOS. The logical question is what will be the impact of Brillo upon the other two major frameworks, IoTivity and AllSeen? Will they be forced onto a path of convergence under the Open Linux Foundation and become the free spirits of the IoT? The future will tell.
From an Application Layer perspective, Weave is an interesting announcement, as it is positioned similar to ZigBee’s Cluster Library. Because it was explicitly mentioned that it was developed in cooperation with Nest developers it will be safe to say that it will run on top of Thread – putting it head-to-head with the April announcement of the ZigBee Alliance and the Thread Alliance to work together with Thread as well. So, besides ZigBee PRO and Thread going head-to-head for the same space, we now also have the Weave going head-to-head with the ZigBee Cluster Library, and it will be interesting to see how this is going to work out in the near future.
So what happens now?
Is this is going to be real war, or are the industry groups and companies going to come together to create a unified standard that all will benefit by? The earlier this is all sorted out, the better, because history has shown that standards wars are costly for winners and losers. As well of course, for consumers, end-users, integrators, IoT & smart home service providers, and product manufacturers.
Confusion in communication standards is not conducive for market acceptance of new applications. Clarity in standards is key for the market to grow.
There are lots of very rosy predictions for the exploding size of this market – but unless there is some movement to come together – to work together – the big IoT boom may wait a little longer.
Cees Links is the founder and CEO of GreenPeak. Under his responsibility, the first wireless LANs were developed, ultimately becoming household technology integrated into PCs and notebooks. He also pioneered the development of access points, home networking routers, and hotspot base stations. He was involved in the establishment of the IEEE 802.11 standardization committee and the WiFi Alliance. And, he was instrumental in establishing the IEEE 802.15 standardization committee to become the basis for the ZigBee sense and control networking.
In 2005, Cees started with GreenPeak Technologies. GreenPeak is a fabless semiconductor company and the leader in the ZigBee market with a rich offering of semiconductor products and software technologies for Smart Home data communications and the Internet of Things. You can contact GreenPeak at http://www.greenpeak.com.