A smart home is a home in which appliances, lights, locks and sensors are connected to the internet, so that the owner can control them from a phone or by voice, and they can act on their own. Each such device is part of the internet of things, or IoT: everyday objects that contain a small computer and a network connection.
Every connected device has three layers of software. Firmware is the software on the device's own chip. It controls the motor, the heater or the light. An app on the owner's phone lets them control the device. The maker's cloud, its servers on the internet, joins the device to the app, collects the device's data and sends it updates. This design is explained in IoT architecture.
Here is a typical case. An accountant leaves home at 9 a.m. with clothes loaded in the washing machine. At 4 p.m., she starts the wash from the app, so that it finishes as she gets home. The command goes from her phone to the maker's cloud, and from there to the machine over the home Wi-Fi. When the cycle ends, the machine reports this to the cloud, and the app shows her a message.
The zone has two kinds of product. The first kind is the devices that a family buys. These are smart home appliances such as washing machines, fridges and ovens; smart lighting; smart thermostats and home security systems; and new devices such as the cooking robot, which cooks a whole meal unattended. The second kind is the parts that device makers buy and build in. Voice assistant modules are ready-made boards that let a device understand spoken commands, using speech recognition. IoT wireless chips are low-power radios that let a sensor run for years on a battery.
For devices from different makers to work together, they must follow shared connectivity standards, such as Wi-Fi, Bluetooth, Zigbee and Thread. A newer standard called Matter, agreed by the large phone, speaker and appliance makers, aims to let one app control devices of every brand.
Why do appliance makers do this? They earn little on each machine. Connected features help a brand stand out. They can bring in subscription income, for example for home-security monitoring. And the data on how machines are used helps the maker plan service visits and design the next model. Several of the world's appliance makers write this software in their centres in Bengaluru and Pune.
Each connected device is also one more device on the home network that an attacker could try to take over. So makers must keep sending security updates for years after the sale.