INTEGRATION
Methods of Communication Making Sense of Smart Home Protocols Now and in the Future By Jay Basen
When I first started automating my home in the 1980s, X10 was the only protocol that enabled information to be communicated between smart home devices. Thankfully, there is now a wide range of modern smart home protocols and devices that incorporate them. Protocols used by today’s smart home devices include: Zigbee, Z-Wave, Z-Wave Long Range, Bluetooth Low Energy (BLE), Wi-Fi, Thread, HomeKit, DotDot, and Sidewalk.
Zigbee is an open standard wireless protocol designed to allow IoT devices to communicate with each other. Its devices primarily operate at 2.4 GHz, which is the same frequency range as Wi-Fi. Similar to Wi-Fi, Zigbee breaks down the 2.4 GHz frequency spectrum into a series of channels, so a channel can be chosen for devices to communicate on to minimize the amount of interference from Wi-Fi. Zigbee devices operate as a mesh network, which will route communications through other Zigbee devices in the home to work around interference.
most part, negates this limitation as communications can hop from one Zigbee device to another.
Theoretically, up to 65,000 Zigbee devices can exist in a single Zigbee mesh network. However, the practical limit is more on the magnitude of a few hundred, which should be more than adequate for even a very large smart home.
from a high definition security camera to a smart display.
The data rate of communications between Zigbee devices is 250 Kbps. Wi-Fi speed, in comparison, is measured in Mbps (1 Mbps is 1000 times faster than 1 Kbps). So, while the speed of Zigbee is perfectly adequate for communications between, for example, a smart light switch and a Zigbee hub, it isn’t a protocol that you would want to use for streaming video
Z-Wave
With much thanks to Johan Pederson, manager, product marketing – smart home & consumer IoT at Silicon Labs, this article will try to make sense of today’s smart home protocols and talk about the changes coming in the near future. The Zigbee standard was developed by the Zigbee Alliance, which re-branded itself as the Connectivity Standards Alliance (CSA) in 2021. Today, the CSA is a consortium of more than 350 companies in more than 37 countries and is “on a mission to simplify and harmonize the IoT.”
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Residential Tech Today | Nov/Dec 2021
The Zigbee protocol is designed to be very secure and also very reliable. It includes 128-bit AES encryption and offers features such as retries of lost messages and acknowledgements when messages are received. Zigbee devices theoretically have a range of between 75 and 100 meters indoors, but a more practical limitation is around 40 feet. The mesh networking ability of Zigbee devices, for the
Whereas Zigbee devices primarily operate in the 2.4GHz band overlapping the frequencies used by Wi-Fi, Z-Wave operates at 908/916MHz in the U.S. This lower frequency eliminates any interference with Wi-Fi. In addition, the lower frequency does a better job of penetrating through the walls in a home. Z-Wave devices can reliably communicate at distances up to 100 meters, but the lower frequency range of the protocol means that data throughput is lower. Z-Wave only transfers data at 10-100kbps, which is still adequate for
