From B to Z: How your smart home speaks wireless
Wi-Fi, Bluetooth, NFC, UWB, Zigbee and Z-Wave: How your wireless smart home works
Smart devices are only smart because they talk to each other. But like English, Mandarin or Urdu, there are several different wireless protocolsthat smart home technologies use to communicate, including Wi-Fi, Bluetooth, NFC, ZigBee and Z-Wave.
Most smart home devices support some or all of these wireless standards. Some are used to carry very simple packets of data, like instructions to switch on or off, or a reading like ambient temperature, while others ferry sound and picture from one device to another.
In no particular order, here is a quick look at all of the wireless technologies operating in your smart home.
Wi-Fi is the wireless backbone of your smart homeiStock
The most powerful and arguably the easiest to understand, Wi-Fi is what connects your smart home devices (plus your computer, phone and more) to the internet, via your router. Wi-Fi has come in many different flavors over the years, with each new iterations bringing greater speed, coverage and bandwidth than before.
Standing for wide fidelity (as opposed to your hi-fidelity sound system), the Wi-Fi standard is overseen by the Wi-Fi Alliance and was introduced in 1998. The different forms of Wi-Fi can be expressed as a suffix after the common 802.11 prefix. For example, Wi-Fi 4 is also known as 802.11n, Wi-Fi 5 is 802.11ac and the latest, greatest Wi-Fi 6 is 802.11ax. These standards have a high degree of backwards compatibility, so it is usually the case that an older device with Wi-Fi 4 will still work with a Wi-Fi 6 router, even though it might lack the performance of a Wi-Fi 6 device.
The range and bandwidth of Wi-Fi make it perfect for carrying large amounts of data quickly throughout your smart home. That said, it can struggle to penetrate the thicker walls of older homes, or completely cover larger properties. This is why Wi-Fi signal boosters are useful smart home accessories, repeating the signal emitted by your router to help improve signal throughout the home.
Building a mesh Wi-Fi network can also be a good idea, where several routers located throughout the home help to create a larger and more stable network for all of your devices, from televisions, computers and game consoles, to light bulbs, speakers and thermostats, to connect to.
Wi-Fi is the backbone of your smart home, and ensuring a good connection in every room is important before going much further with the building of your smart home.
Bluetooth is commonly used in various smart home devicesiStock
Bluetooth has been arrived for over 30 years and is overseen by the Bluetooth Special Interest Group. The unusual name comes from 10th century Danish King Harald Bluetooth, known for uniting Danish tribes into a single kingdom – like how Bluetooth helps many different devices connect with each other.
Bluetooth connections are used for device-to-device connections, usually between a smart home device and your smartphone when they're within around 30 feet of each other. You'll rely on this for smart home gadgets, such as door locks, only when you're in close proximity.
Some smart lighting systems use Bluetooth, and Signify recently added the option to its newer Philips Hue bulbs, allowing them to connect directly to a smartphone and the Hue app instead of first to the Hue Bridge.
Bluetooth is also commonly used for connecting wireless gamepads to games consoles and other devices like computers and tablets, and is used to connect a smartphone or a wireless speaker or headphones.
Smart speakers, like the Amazon Echo and Nest Audio, connect to the internet using Wi-Fi, but can also be used as a Bluetooth speaker via your phone.
NFC is most commonly used for contactless payments in storesiStock
NFC stands for "near field communication" and transfers commands between devices that are no more than four centimeters apart. Because the devices need to be so close, NFC is often referred to as “touch-to-pair." Instead of adding a device to your home network through a series of on-screen prompts, NFC let's you "tap" the new smart device to a NFC-enabled Wi-Fi router, smart home hub or similar smart home device to then add it to your network.
This setup process makes it easy to connect a new speaker to a smartphone, for example, while NFC tags can be used to trigger smart home automations and routines.
NFC is most commonly found when paying for items in stores, or travelling through public transit systems like the New York subway and London Underground. Here, a tap of your NFC-enabled credit card or smartphone completes the transaction. On a similar note, the technology is used by smartphones to unlock certain compatible models of car.
With its relatively limited 35-foot range, ZigBee is often used for device-to-device communication by top cable providers Comcast and Time Warner as part of their whole home systems. ZigBee is the more power-efficient and faster-to-respond of the two, often found on smart home devices that operate on batteries such as sensors and remote controls.
Zigbee operates on the 2.4GHz, 90MHz and 868 MHz frequencies, and has a data transfer rate of just 250 kilobits per second, significantly slower than even the worst Wi-Fi connection. Up to 65,000 Zigbee devices, known as nodes, can operate on the same network, meaning for smart homes the number of products connected at once is virtually limitless. There are more than 2,500 ZigBee-certified products from more than 400 member companies of the non-profit ZigBee Alliance.
Developed by Danish company Zensys in 2001, Z-Wave is a wireless networking protocol primarily designed for use in home automation. Because the technology is owned by a single company, the Z-Wave standard has remained exactly that — a standard — and as such every Z-Wave device works with every other. This differs slightly from Zigbee, which is broken up into several different protocols and devices from one protocol do not always communicate with those from another.
Zigbee has an operating range of around 100 feet and is considered to be slightly more reliable, and is favored by smart home security providers such as ADT, First Alert and Honeywell. The Z-Wave Alliance boasts of 3,200 certified devices available from 700 companies.
Although ZigBee and Z-Wave can't speak to each other, many smart home devices support both protocols to make it easier for consumers to mix-and-match devices within a smart home system. The right blend will be up to you.
The newest wireless technology to enter the smart home is called Ultra Wideband, or UWB. This technology has only featured on a handful of products for now (as of February 2021), but it has great potential. UWB chips are already fitted to some high-end smartphones, such as the Samsung Galaxy S20 and S21, and the iPhone 12. These chips don't do much for now, but companies are starting to show what UWB is capable of.
An early example is how the iPhone 12 and HomePod mini smart speaker use UWB to understand each other's location. The iPhone then alerts the user and offers to hand over much from one device to the other. Bluetooth could do this too, but UWB's strength is its far greater accuracy when used over short distances. It operates at a very high bandwidth, hence the name, and covers a large portion of the radio spectrum.
Samsung is to use UWB technology with a future version of its new Galaxy SmartTags, and both Tile and Apple are expected to release their own UWB-powered possession trackers later in 2021. Again, these are expected to work better than their preexisting Bluetooth equivalents.
As well as greater accuracy, UWB is a more secure means of data transfer than Bluetooth and NFC, making it a good option for the increasing trend of replacing car key fobs with smartphones. Some car manufacturers already allow a smartphone with Bluetooth to be used instead of a key, but it is likely that they will switch to UWB once the technology has rolled out to more handsets and proved itself as the superior, safer and more precise option.