HOWA SMART HOME WORKS
Understanding how your smart home fits together will make it easier to connect the building blocks. Here we show you how everything works
Building a smart home is a little like building a Lego model: you put the basic blocks together to create the system that you want. The important thing is to know which blocks you have to play with and how they can connect. To start, then, we’ll show you how a smart home works, how the components communicate with one another and how you can connect everything. SMART HOME COMPONENTS First, and most important, are the actual smart home components. These are the devices such as smart thermostats, smart light bulbs, video cameras, smart plugs that you can turn on and off, and even robotic vacuum cleaners.
A smart device is one that you can communicate with via your home network and over the internet. Every smart device is controllable via a dedicated smartphone app, giving you full access to each product’s full set of features. Over the next few pages and our smart thermostat group test (see page 92), we’ll help you choose the products that will work best for your home. OBSERVING PROTOCOL To be controlled from your phone or a voice assistant, smart devices have to connect to your home network. For some that means they have a built-in Wi-Fi connection, connecting like a traditional laptop or smartphone. Wi-Fi is typically used for kit that needs a high-speed internet connection and is also permanently wired into place, such as a security camera.
In many cases, Wi-Fi isn’t ideal for several reasons. First, Wi-Fi is power hungry, so it’s no use in battery-powered devices, such as smart door sensors for an alarm system. Wi-Fi’s range can also be an issue, and some devices could be at the periphery of range. Finally, Wi-Fi isn’t that reliable, and devices can drop their network connections.
Instead, many devices use a dedicated smart home protocol, such as Zigbee or Z-Wave. These protocols are very low power (battery-powered devices will last for months, if not years), have excellent range (and many devices act as repeaters to further boost range), are very reliable, and work efficiently and quickly.
The issue is that your smartphone and other devices don’t speak the same smart home language, which is where you need a bridge or hub. These boxes plug into your home network, usually via Ethernet, and translate the commands from your smartphone’s Wi-Fi into the smart home protocol’s own language. Many products have their own unique hub but some bridges, such as the Samsung SmartThings hub, can talk to many devices that use Zigbee or Z-Wave. DIRECT CONTROL Using devices that utilise a smart home protocol gives you more control options. It’s common to find battery-powered remote switches and buttons that talk natively to a
smart home device. For example, the Philips Hue system uses battery-powered Zigbee light switches and remotes that give you direct control over your lights. This would be impossible using Wi-Fi, as the remote would either run out of power too quickly or would take too long to establish a Wi-Fi connection, making the product annoying to use. VOICE ASSISTANTS The latest component for smart homes are voice assistants such as Amazon Alexa, Google Assistant and Apple Siri. Typically, these systems have a smart home speaker system that sits in your home and listens for commands. With these systems, you add ‘Skills’ that let the voice assistant control your smart home devices. For example, you can say, “Alexa, turn on the lounge light”.
As voice assistants can talk to multiple devices from multiple manufacturers, you can control everything from one place, removing the need to dive into loads of different apps. Usually, you can group devices together, for example turning off your Philips Hue living room light and your Smart Things controlled lamp with a single command.
You should therefore make sure that the devices you buy are compatible with the smart assistant you want to use. IFTTT Further control comes from If This Then That (IFTTT), which is a cloud-based service. Using simple rules, you can control how your smart home devices work. For example, if motion is detected on your security camera, you can have your lights turn on automatically to scare away would-be burglars.
IFTTT is extremely powerful and flexible, but actions can take a few seconds to occur, so it’s not very good for direct control. For example, using IFTTT with a smart motion sensor to turn on your lounge lights isn’t particularly helpful if that action takes upwards of five seconds to occur.
When choosing your smart home devices, then, look at whether it supports IFTTT or not. Our reviews always explain what’s possible with the system. AUTOMATION The final piece of the puzzle is home automation, which could be provided through a service such as IFTTT, via dedicated hardware sensors (motion sensors, door sensors and the like) or even in-app. This kind of control lets you perform tasks automatically, and the scale of what you can achieve is enormous. For example, you can have your lights slowly become brighter to wake you in the morning; a motion sensor can trigger a light to turn on and off automatically; you could have a security camera turn on when you go out; or you could have your heating turn off when an outdoor temperature threshold is reached. Control varies between products, but we’ll show you how to get started with automation later in this feature.