In order for devices in your smart home to communicate with each other, you must use so-called smart home protocols. What are Smarthome protocols and what can they do for you? Plus: can you connect all devices with this? We take a look at it in this background article.
If you are active on this site, then you are at least interested in smarthome: devices, services, integrations, you name it. Chances are that you also have some devices at home that can be controlled smartly and may also communicate with each other. Then you have probably run into various thresholds. Not just for getting all kinds of equipment working; especially that linking can be difficult when devices do not speak the same language among themselves. That’s where smart home protocols come in handy.
Smarthome protocols: the basics
Basically, a smarthome protocol is a language: a way of communicating. If devices speak the same language, they can exchange data and as a user you can control multiple devices with one app or voice assistant. If they all speak other languages, you often need multiple apps and voice assistants to get everything done. That is why it is nice to see manufacturers fighting for standardized protocols on their own. Protocols that already exist, such as WiFi and Bluetooth, or Z-wave and Zigbee.
Both Zigbee and Z-wave are wireless smart home protocols that work over a mesh network . They consume little energy and can therefore also work on devices that have batteries. Connection can be established in two ways. For example, users can buy and install an extra box (a switch or hub) with the standard on board (the lamps from Philips Hue and Ikea both have such a box). You can also think of a hub such as the Homey or the SmartThings hub not available in the Netherlands .
If you have a hub or box that supports both Zigbee and Z-wave, you can connect a lot of devices to each other. You don’t have to choose between the two standards and can use the products you want. Another option is to use the Wi-Fi connection. You usually already have this at home and you do not need any additional hardware for that. The WiFi connection is best for devices that are actually always on, such as lamps or smart sockets. This way there is always a guaranteed connection.
Z-wave
Z-wave is a self-developed standard owned by the company Sigma Systems. Companies wishing to equip products with Z-wave must be a member of the Z-wave Alliance, an organization created to promote the smart home protocol. By using Z-wave, you can connect devices that do not necessarily come from the same manufacturer. For example, you can combine a light switch from manufacturer X with the smart lamps from manufacturer Y and everything should work; because it is one system.
Z-wave is basically a standalone mesh network. The signal from this network is amplified by other Z-wave devices in the house, so there should be no connection problems. This function is only available on devices with a plug and without a battery. The protocol can transmit up to 100 kbps of data. That may not sound like much; however, the system only needs to be able to handle simple commands (turn on or off the lamp, etc.), so that more is not necessary. Some useful options of Z-wave are:
- runs on 900 MHz spectrum
- can spread signal up to forty meters (with the latest chips)
- signal can jump between four nodes
- support up to 232 devices in the home
- also supports the state of the device, so you can see if something is on or off
Zigbee
Zigbee also has its own cooperation organization, called the Zigbee Alliance. Companies can use different profiles that ensure that devices are compatible with the smart home protocol. However, with Zigbee you are not sure that all devices can communicate with the standard on board. For example, Philips Hue lamps work with Zigbee, but they don’t work without the company’s hub. The standard operates on the 2.4 GHz band, while also using 866 MHz.
The devices with Zigbee on board can also serve as so-called repeaters: devices with a plug can amplify the signal of the mesh network that you have set up yourself with a maximum range of twenty meters. Here also applies that devices with only a battery do not have this function, in order to save battery life. The data is sent over a speed of 250 kbps: fast enough for simple signals and checking whether something is on or off. It is also possible to use up to 65,000 devices in one Zigbee network.
Wifi
The most famous connection standard of all smart home protocols is undoubtedly Wi-Fi. You are already using this standard on your smartphone, television, computer, game console and much more, probably. It is therefore not surprising that there are smart home manufacturers that use WiFi for mutual communication, such as the Lifx smart lamps . Usually Wi-Fi has a range of forty meters, but various factors, such as walls, play a role in the usability of that signal.
In addition, WiFi has the disadvantage that you can only connect up to a hundred devices in the house. One hundred is the maximum, but before you reach that number, you will already run into connection problems. It is possible to increase the number of maximum devices that are connected to 254, but that also causes problems and we cannot recommend it. If you still want a good signal at home, consider the different mesh systems. For example, we tested Google Wifi and the Devolo Magic 2 adapters .
Other smarthome protocols
The three above smarthome protocols are the most popular at the moment. But there are also other options. We have not yet mentioned Thread and bluetooth for example. Thread works much the same as Zigbee and devices can therefore communicate with each other. Thread devices can also be controlled from the cloud. The energy-efficient bluetooth is also sometimes used for local communication, but has the disadvantages that it is slow, has no great range and does not work online.
In addition, many smart home products unfortunately / fortunately work with their own smart home protocols. You may cross out for yourself what does not apply. The advantage of proprietary smarthome protocols is that manufacturers have complete control over how devices communicate and act. The disadvantage is that often no communication is possible with other devices, so you are dependent on a specific app or voice assistant. An expansion of the possibilities is usually not planned.
Can smarthome protocols communicate with each other?
Basically this is not possible. A Zigbee button cannot turn on a Z-wave lamp. However, as we just mentioned, it is possible to have communication via a smart home hub that offers support for different types of smart home protocols. For example, one light switch can suddenly switch on both the Philips Hue, Ikea and Lifx lamps, if you have many different types of lamps at home (we cannot recommend, but the different lamp brands serve as good examples).
You can also use external services or smart home platforms. Read more about IFTTT , a handy automation service, and everything you want to know about smart home platforms here
