Zigbee, Z-Wave, Wi-Fi, should you care which Wireless Technology your Smart Home Device uses?

June 11, 2021

The answer is Yes, you should care which wireless technology your smart home device uses as that has a significant impact on convenience, reliability, interoperability, and cost. Let’s discuss the 4 major wireless technologies used by smart home devices, ZigBee, Z-Wave, Thread, and Wi-Fi Smart Switches. We won’t consider Bluetooth or RF as these have specific use cases and are not applicable to most smart home devices.

Zigbee

This is an open-source short-range wireless technology that operates between 10m to 20m range indoors. Zigbee devices can connect to each other in a mesh network. This way, the nearest device can help transfer data to other devices in the network, allowing wireless data transmission in larger spaces. If you want to control your Zigbee device from anywhere in the world, it will need to connect to the internet via a hub. This means purchasing an additional piece of hardware along with your devices. A drawback of Zigbee technology is that different product vendors might implement Zigbee in slightly different ways, making their hub incompatible with each other, so you may end up needing different hubs for different Zigbee products. Another drawback is that different Zigbee products may cause interference with each other due to the lightweight nature of the protocol, i.e., requiring less handshaking, less fault tolerance as compared to TCP/IP. One advantage of this being lightweight is that it consumes less power, making batteries last longer. However, if your smart home devices are going to be connected to a permanent source of power, then this isn’t a significant advantage.

Z-Wave

This is similar to Zigbee, except it is a proprietary technology owned by Sigma Designs and now controlled by the Z-Wave Alliance. It operates on a 0.9 GHz band, which means it does not interfere with other frequencies. Also, this lower frequency allows a longer range of signal at a slightly reduced bandwidth. This also implements a mesh network similar to Zigbee, but the only thing to remember is it allows a maximum of 4 hops before it has to reach its destination. As this is a strictly controlled protocol, multiple devices from different manufacturers should be able to talk to each other. A couple of disadvantages are that these devices usually cost more, and the implementation of this technology requires a separate hub to connect to the internet.

Thread

Thread is an evolution of Zigbee and looks like this will soon be the technology replacing Zigbee. A Thread network will consist of multiple nodes that can communicate with each other, creating a mesh network. These nodes can either be routers or endpoints depending on whether they have a permanent source of power supply or not. Endpoints will typically just communicate with the next available node, but the routers can route the information around the network. To get the information back and forth from the internet, there will need to be a border router. Thread has been designed for smart home applications where battery life and power consumption are very important. For end-users, there will be very little to do as these networks self-configure themselves, set themselves up as routers or nodes as soon as they are powered on and reconfigure themselves if a device is removed from the network. There have been some big names creating products with this technology that have gained a lot of attention, such as Apple (HomePod Mini), Nano (Leaf Bulb), Eve Products, etc. This is a technology that is still to gain traction, but all the indications are this will be something to look out for.

Wi-Fi

This is a universal technology used by most devices at home. Home Wi-Fi operates at two major frequencies, that is the 2.4 GHz range and the 5 GHz range. The 2.4 GHz allows longer coverage (up to 100 meters) with good bandwidth. The 5 GHz range allows even higher bandwidth but reduces the signal coverage significantly. The data is transferred using the reliable TCP/IP protocol. The devices that use Wi-Fi Smart Switches technology consume more power when compared to Zigbee or Z-Wave, however, if these smart home devices are going to be connected to a permanent power source, this is not an issue. Also, as this is the range at which all the wireless routers work, there is no need for a separate hub.

At iotics, we recommend you purchase smart home products that use Wi-Fi Smart Switches technology if power is not an issue but implement a good wireless mesh network at home so there is a great wireless signal in all areas.