Z-Wave is a wireless network protocol developed by the Danish company Zensys in 2001 and is mainly designed for home automation. Z-Wave was acquired by Sigma Designs in 2009, and then sold to Silicon Labs for a price of US $ 240 million in early 2018.

Because the technology is owned by a company, the Z-Wave standard is always maintained as a standard, and each Z-Wave device can be used in conjunction with each other. This is slightly different from Zigbee. Zigbee is divided into several different protocols. Devices that support one protocol do not necessarily mean that they can communicate with devices of another protocol.

However, devices that support the new Zigbee 3.0 standard can communicate with all Zigbee products, and this issue has been resolved

Z-Wave Alliance


The Z-Wave Alliance has more than 700 members and has more than 2,600 certified products. This number has grown from 1,700 in 2017 and 6 in 2005 to the present. There are more than 100 million Z-Wave devices in operation worldwide, and the Z-Wave Alliance claims that 90% of leading security companies use Z-Wave in their products.

Z-Wave operates in the 800-900MHz frequency range. This means that, unlike Zigbee, Z-Wave cannot operate on the 2.4GHz frequency used by Wi-Fi, which may cause interference problems. Also because Z-Wave is far away from this frequency, it can avoid interference from nearby Wi-Fi devices.

Like Zigbee, Z-Wave’s power consumption is much lower than other wireless technologies (such as Wi-Fi and Bluetooth), which means that the device does not require frequent battery replacement. In some cases, it may only need to be replaced every ten years. Unlike Wi-Fi and Bluetooth, Z-Wave is designed to transmit small amounts of data, such as commands and information from devices such as motion sensors. It also does not have the bandwidth as Wi-Fi, but for example, the amount of data transmitted when the Z-Wave switch requires the smart light bulb to be turned on does not need such a large bandwidth.


Mesh network


Like Zigbee, unlike most traditional Wi-Fi networks, Z-Wave uses a mesh network (of course, the latest WiFi6 also supports mesh networks), so every device on the network can communicate with other devices. This means that if a device fails or exceeds the range of the smart home control center, the information can still communicate to the target device.

Z-Wave’s mesh network does not send data directly from the WiFi router to the target device (such as a smartphone or computer), but sends data from the control center to one device, and then to another device, so all networking Of devices are in network coverage.

For example, each Z-Wave product connected to a power source acts as a repeater, transmitting all information sent over the network to each Z-Wave device in the home. The latest 700 series (launched at the beginning of 2018), Z-Wave has a transmission distance of 300 feet (about 90 meters) in an open environment, but in fact the signal only needs to travel a short distance between one device and the next The signal will appear repeatedly and continue to be sent, so there is basically no coverage problem for home applications.

A Z-Wave network can connect up to 232 devices (or nodes). Although it is far less than the Zigbee network that can build 65,000 nodes, for most smart homes, 232 is enough. These nodes include every smart device in the home, such as smart light bulbs, smart switches, smart dimmers, motion sensors, smart doorbells, smart door locks, smart thermostats, smart sockets, smart cameras and smart alarms, etc.

In December 2019, the Z-Wave Alliance released the Z-Wave specification. The network layer and communication protocols have been opened up, allowing more technology companies and component manufacturers to use them. The alliance said this means Z-Wave will become “a multi-source wireless smart home standard developed by all members of the Z-Wave alliance working group.” This move will enable more companies to join the alliance and make Z-Wave technology available in the IoT There is a wider application among manufacturers.