Why not Bluetooth in the smart home instead of Thread?

On our most recent IoT Podcast episode, Chris called in to our podcast hotline asking for our thoughts on Bluetooth in the smart home as compared to the new Thread protocol. Both Bluetooth and Thread support mesh networks so Chris is wondering if Bluetooth will be supplanted by Thread and if we think the two standards will coexist in the smart home of the future.

Clearly, many people are wondering about Thread as we continue to get callers asking about it as compared to other wireless protocols such as Bluetooth. And we can understand, considering that a high level, both appear to be similar. However, Bluetooth is a multi-purpose solution (think audio, small file transfers, computer peripherals, and more) while Thread is custom-built for a single purpose: smart home device to device communication.

To be clear, we don’t think Bluetooth is going away any time soon as a valuable smart home protocol. If you have Bluetooth devices today, they’re going to continue to work for quite some time. Bluetooth is also nearly as ubiquitous as WiFi too: It’s in most computing devices, including smartphones, some televisions, and many audio products.

And the Bluetooth SIG recently shared a 2021 market update (PDF) with data on the most used smart home implementations for Bluetooth, showing that there’s plenty of room for Bluetooth in both smart lighting and smart appliances.

Plus, it’s a great solution for device provisioning. When you buy a new connected device for your smart home, it’s quite common to open a mobile app for the device, which then finds the new device over Bluetooth.

That’s far easier than using WiFi for provisioning, which typically requires setting up a peer-to-peer WiFi connection between your phone and a device for the setup process. However, there does seem to be a movement towards using NFC and QR code scans to start the pairing process as well.

Chris is correct in that Bluetooth mesh is becoming a bigger force in industrial lighting. Just a few weeks ago we noted that the Bluetooth SIG worked with the Digital Addressable Lighting Interface (DALI) for Bluetooth mesh gateway support with industrial lights. So while Bluetooth may be supplanted by Thread in future smart homes, it still has a home in the industrial space.

The market will obviously decide between the two. But my own experiences with Thread show faster response times and more network reliability than I’ve seen with Bluetooth.

So we wouldn’t recommend buying new Bluetooth devices going forward if you can wait. There is room for both protocols, but when it comes to most smart home devices, particularly those that run on batteries, Thread is looking good so far.