Smart devices are only smart because they talk to each other. But like English, Mandarin or Urdu, there are several different wireless protocols that smart home technologies use to communicate: Wi-Fi, Bluetooth, NFC, ZigBee and Z-Wave.
Most smart home devices support some or all of these wireless standards.
Wi-Fi: This is the standards for all wireless connectivity. While every smart home devices supports its own wireless protocol, all will operate on Wi-Fi. Wi-Fi is a smart home constant because it has the widest reach – around 150 feet – of all wireless communication methods. That means you can control your smart home devices from nearly anywhere in your abode. Once a smart home device gets connected to your home Wi-Fi network it can talk to other smart devices also on the same network, and, if necessary, to the Internet.
Bluetooth: 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.
NFC: 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.
ZigBee/Z-Wave: While Wi-Fi, Bluetooth and NFC are established wireless standards, ZigBee and Z-Wave, are more secure wireless connectivity protocols designed exclusively for smart home devices.
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 Z-rivals, often found on smart home devices that operate on batteries such as sensors and remote controls. There are more than 1,200 ZigBee-certified products from more than 400 member companies of the non-profit ZigBee Alliance.
Z-Wave has an operating range of around 100 feet and is thought to be slightly more reliable, favored by smart home security providers such as ADT, First Alert and Honeywell. The Z-Wave Alliance boasts of 1,300 certified devices available from 325 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.
Read GearBrain's What is Z-Wave and how does it work to automate my smart home? to get an update on Z-Wave and What is Zigbee and how does it work to control my smart home? for an update on Zigbee.
For help installing any smart home system, you can visit HomeAdvisor.com to find a trusted local professional to help you.