Why do we need smart home hubs?
February 06, 2021
What are they, and why do we need them? 💭
A cikk magyar változatáért kattints ide.
One of the most common questions users ask when starting a smart home project is, “Isn’t it enough just to buy the devices?”
Usually, no. While some devices can function without their own hub, you typically need some kind of central controller for several technical reasons.
Sure, going without them is possible, but it’s generally not a good idea for a few reasons. Although promising technologies like various mesh solutions exist—such as the Thread protocol, which currently seems one of the best options, or other protocols and standards—the basic concept is simple:
To control your devices, you usually need some kind of central unit to handle this task. Building all the necessary control mechanisms into a light bulb or a small sensor wouldn’t be very cost-effective or feasible. It’s much easier if a hub manages device connections and state changes. This is especially important if you want to control your devices remotely, as it’s pretty rare for such setups to work well without a hub. While many communication standards exist (Bluetooth, Zigbee, Z-Wave, etc.), a hub is almost always required for proper functionality.
Okay, but it’s frustrating that everything has its own hub! 💢
It would definitely be more convenient if everything didn’t need a separate hub, and that’s something we can move toward. In the HomeKit ecosystem, quite a few smart accessories are now available that don’t require their own hub—they just need power and internet, and they’re good to go.
Everything works fine as long as your network (Wi-Fi, Bluetooth, etc.) coverage is stable and the devices don’t lose connection to each other or the internet. You can control your devices easily if you’re at home and the devices are physically close. But as soon as you want to manage them remotely—from work, for example, or when you’re out of direct communication—you’ll need a central hub. In HomeKit, this role can be fulfilled best by an Apple TV, but HomePod and HomePod Mini can also function as central hubs for your HomeKit system.
But I have a HomeKit Hub, so why do some devices need another one? 🙋♂️
This is usually a decision made by the manufacturer. For example, the Philips Hue lighting system I use also comes with its own hub (which they call a bridge 😊), and the lights’ smart features don’t really work without it.
In this case, your commands are sent over the internet to the hub (or bridge), which then passes the instructions along to the devices (e.g., light bulbs). Sometimes, the technical limitations of the devices you’ve chosen can cause problems. For instance, Bluetooth-controlled devices tend to be unreliable, so I avoid Bluetooth-only smart home devices as much as possible.
An Apple TV 4K serves as the primary HomeKit hub in my setup. Still, I also have four HomePod Minis in a stereo setup next to the TV and in the bedroom, so either could take on this role independently. I use a Philips Hue system (related article here) for lighting, so a Hue Bridge is also part of the setup for controlling the bulbs and switches.
For non-HomeKit-compatible smart devices, I use a Raspberry Pi 4B running Hoobs as a hub. In the next article, I’ll explain more about the Hoobs and HomeBridge systems and why I chose them.
