State of the Smart home protocols

The smart home space is still stabilizing and because of this, there are many different technologies that are still used. One of the key components for a smart home to function properly is the underlying communication protocol. This is different to the brand of device like Alexa/Google you are using but how the bits are getting transferred.

The communication protocols allow devices to share information and give control. Through these messages is how you can ask Alexa to turn off your light. This is what is defined as the Network Access Layer, it is the physical infrastructure that allows 2 devices to communicate.

In the IoT space there are quite a few protocols in use. Some were developed specifically for IoT and some are taken from existing technologies.

Here are a few considerations of a protocol used in a smart home.

• Range - Can all your devices communicate with each other?
• Stability - Is the connection always up?
• Power consumption - How much energy does the communication use?
• Data transfer rate - How much data can you transfer per second?
• Security - Can someone easily intercept your network?

WiFi

Backed by: WiFi Alliance

Everyone will be familiar with WiFi, the protocol that gets you access to the internet. This is used in some older IoT products but is increasingly not the flavor.

You might notice that a WiFi connected device will require you to use 2.4 Ghz WiFi instead of the modern default of 5 Ghz. The reason here is that of coverage. A longer wavelength helps it penetrate your walls much better allowing for a more stable connection.

A major downside of WiFi is its energy consumption. There’s a reason that your headphones all work through Bluetooth rather than WiF! For IoT devices that run off battery, this is a crucial factor as it would be very inconvenient to change your motion sensor battery every 2 weeks. This is why the devices that do use this device are almost always plugged in such as this light bulb from Tapo.

Bluetooth Low Energy

Backed by: Bluetooth Special Interest Group

Notable companies: Xiaomi

Bluetooth itself is a widely used protocol which many will have used to connect wireless headphones and wireless mice. A flavor of this technology, originally named Bluetooth Smart but now more well known as BLE (Bluetooth Low Energy) is used in IoT devices. The main difference between BLE and Bluetooth classic is the power consumption. By lowering the specs of the data transfer rate, it drastically lowered the energy consumption by 2x to 100x.

The protocol is used in battery powered sensors such as this Xiaomi BLE Temperature sensor.

Zwave

Backed by: Zwave Alliance & Silicon Labs

Notable companies: Ring

Zwave, introduced in 1999 is one of the first standards dedicated to IoT devices. It boasts using a mesh network and has low power consumption. I won’t go into too much detail here but this is a network where each device could be connected with each other, rather than having only one centralized router (as you would for WiFi). This makes the network stronger with higher availability. It uses a proprietary set of radio frequencies and chips. My assumption is that this made it more expensive to manufacturers and being tied down to a limited company meant that Zwave is trending down.

Zigbee

Backed by: Connectivity Standards Alliance previously known as the Zigbee alliance

Notable companies: Phillips, Amazon, Ikea

Zigbee was developed with IoT in mind. It uses mesh networking (adopting the well known IEEE 802.15.4 standard) and has low power consumption. A lot of big players using this meant that there was quite high adoption but that is all going to change with Thread & Matter.

Thread

Backed by: Thread Group & Connectivity Standards Alliance

Notable companies: Google, Amazon, Apple

You will see that the backers of Zigbee and Thread are the same and this isn’t a typo. Thread is effectively the second attempt for the biggest players to adopt a standard. It uses much of the same technology like IEEE 802.15.4, mesh networking and low power consumption. The difference between Zigbee and Thread is that Thread allows the manufacturer to choose an end user application layer. Thread also uses Ipv6 addressing, standardizing it with the internet and no single point of failure.

However, maybe the most important difference is that. Matter, the latest application layer standard from CSA themselves uses Thread (along with WiFi & BLE). This effectively spells the end of Zigbee.

If you ever get confused, this glossary really helped me understand the different terms and some of the history behind the project.

What does this mean for The Silly Home?

I really hope Matter & Thread is here to stay and truly consolidates the whole smart home ecosystem. No more compatibility issues with different manufacturers will benefit the whole market. This will make it much easier to set up a smart home. There were already false hopes with the Zigbee protocol but with Google, Amazon and Apple on board from the very beginning, it may finally work out.

Matter will also help make The Silly Home easier to implement. One of the next stages of the project is to directly connect to the application layer, collecting streaming data for training models and executing the inference. This would be a huge undertaking originally but now instead of building integration to each and every manufacturer, we can build it for this single protocol.