A Comparison of the Best Smart Home Automation Protocols: Wi-Fi, Z-Wave, Zigbee, and Bluetooth
In this article, I’m going to cover how a smart home works and the different smart home automation protocols that are used to control smart devices within your home.
I'm gonna cover Wi-Fi, ZigBee, Z-Wave, and Bluetooth.
How Wi-Fi Works with Your Smart Home Devices
Wi-Fi is the number one protocol that has been used for a long time.
It has been around for 20 + years. You have your phone connected to it; your computer connected to it.
You can get streaming music on streaming speakers through it.
There is a lot of internet of things connected, smart home devices that work on Wi-Fi.
Wi-Fi is a great platform for the Internet of Things connected devices that have a power source.
It is also very reliable if you have a home network.
It is easy to program connections in between devices with Wi-Fi and it's got a track record that works.
So, if you have an Internet of things smart home product to place in your home and you know you've got Wi-Fi coverage throughout your house, it's going to work (as long as you have a strong network).
Now, the disadvantage of Wi-Fi is that it uses a lot of power.
Really, Wi-Fi is good for devices that will be plugged in or hardwired for a long period of time, so they have the power they need to communicate with your home Wi-Fi network.
A lot of the devices that work with Alexa and Google Home are Wi-Fi devices.
2.4 gigahertz vs 5 gigahertz Wi-Fi networks
Now, another part of this is 2.4 gigahertz vs 5 gigahertz Wi-Fi networks.
2.4 gigahertz is the standard that is utilized for smart home devices for Wi-Fi networks.
A lot of Wi-Fi routers these days have both a 2.4 gigahertz and 5 gigahertz network.
It actually doesn't mean that the 5 gigahertz network is twice as strong or twice as good as a 2.4 gigahertz network.
It’s actually the exact opposite.
The reason why Wi-Fi router manufacturers made these two different bandwidths is that there is a lot of stuff crowded onto 2.4 gigahertz.
On the bandwidth of a 5 gigahertz, there's less crowding.
However, 2.4 gigahertz comes in just as strong as a 5 gigahertz network, if not stronger.
The reason that the networks were made with a different bandwidth was the split-up traffic on networks so Wi-Fi systems could be more reliable and have less interference.
Now, with that being said, the Wi-Fi routers of today are very good.
They have different channels and work really well so you don't have the interference issues that you might have had 5 or so years ago with Wi-Fi.
Here are some recommendations for what is the best Wi-Fi router for your home.
I personally use the Eero system.
The Eero system is great because it repeats throughout the home and it's very easy to expand.
These have been used when building homes, designing homes or installing smart home products in huge houses that are castles that have tunnels in garages, that are in 100 feet away.
Eero has worked great in those settings.
So if you're looking at upgrading your Wi-Fi system, that's an excellent option.
But, getting back to Wi-Fi, 2.4 gigahertz or 5 gigahertz, it doesn't make a huge difference in terms of capacity and stuff going through the network.
What is important to remember, is that the majority of smart home devices connect to 2.4 gigahertz which is the standard Wi-Fi bandwidth.
If you're having problems with a Wi-Fi device connecting to your network, make sure that you're connecting to the 2.4 gigahertz network.
All Wi-Fi routers that have been made in the last 10 years have a 2.4 gigahertz network.
It’s not something that you need to look for on the side of the package or make sure that it has it.
They all have it if they were made in the last 10 years.
So, Wi-Fi is great in terms of compatibility, ease of setup, and for you to know that a product is going to work consistently on your smart home network.
For example, for light switches, Wi-Fi is great. For plugin outlets, a Wi-Fi connection to your smart home is great.
Wi-Fi is also great for hardwired outlets and smart hardwired Wi-Fi fans.
Anything that is hardwired that has a consistent power source, Wi-Fi is the way to go.
A couple of years ago I used to recommend z-wave devices over Wi-Fi.
And the reason was the app development in the development side of Wi-Fi wasn’t as good back then as it is now.
However, Wi-Fi in terms of the standards for smart home protocol and the security aspects that are being built into applications has far surpassed what z-wave was in terms of functionality and usability for the smart home.
So, Wi-Fi is the number one thing I’d recommend if you have a device that can utilize it, that has constant power, that is the way to go.
On the other hand, if you have a battery-powered device, Wi-Fi is not what you want to use.
How Z-Wave Works with Your Smart Home Devices
Now, let's move on to Z-Wave.
Z-Wave is a mesh networking protocol that uses very low energy, is very consistent, has a standard across all Z-Wave devices, and each Z-Wave can repeat the signal of another Z-Wave device.
For example, if you have a Z-Wave smart light switch and a Z-Wave smart plug, those are going to be interoperable.
Z-Wave is great as a mesh network because each node in the home or each device can repeat the signals of other Z-Wave devices.
In other words, the more devices you add to your home, the stronger the Z-Wave signal is throughout your home.
It's a mesh network repeating the Z-Wave signal and for a smart home device like a light switch, it uses very low amounts of data.
It's really just that on-off signal and a status signal.
Z-Wave is great for routing little bits of data throughout your home and creating strong, reliable mesh networks.
Common devices that utilize Z-Wave include light switches, plug-in outlets, smart Z-Wave locks which work really well, motion detectors and sound detectors, and glass break sensors.
There are a lot of opportunities for Z-Wave devices to be implemented in the home.
The other great thing about Z-Wave versus Wi-Fi is that Z-Wave because it uses such a small amount of data, it is very low energy.
This means you can put Z-Wave battery-powered devices on a network and they will last for a long time.
For example, I have had a Z-Wave motion detector - the batteries on that last two to three years.
For Z-Wave locks, the batteries last anywhere from a year to two years based on how cold it is and how much use you have on the lock.
They consistently work and every Z-Wave device makes the network stronger.
Now, the shortcoming with a Z-Wave device or Z-Wave network, is that Z-Wave requires a hub.
There are a variety of different smart hubs out there in the market.
My favorite Z-Wave hub is SmartThings.
What that means is that you need to have a device that converts internet signals into this Z-Wave mesh network signal and then that network signal is repeated throughout your home.
I really like Z-Wave and it is very reliable.
This issue is, not all smart home hubs are as reliable as Z-Wave is.
If the internet service or the cloud service of that smart home hub goes out, your Z-Wave network won’t work.
That's what is really important to understand.
There are some hubs that have battery backup, that have internal programming for your Z-Wave networks, so you’ll have unlimited functionality, unlimited command controllability.
However, the reality is, if it's not up and running at the web service level, it's just not going to be as good as you want or what you intended it for.
So, that is the downfall of Z-Wave, ZigBee, or any of the other protocols that I discuss in this article that aren't Wi-Fi i.e. they, for the most part, require a hub to communicate to devices.
Wi-Fi routers, for the most part, don't have Z-Wave functionality built into them.
How ZigBee Works with Your Smart Home Devices
ZigBee is very similar to Z-Wave.
It’s a great protocol and is used in a lot of devices.
ZigBee isn’t just used just for home automation though.
Z-Wave is a more standard home automation protocol, primarily used only for home automation.
On the other hand, ZigBee is a chip that is manufactured based on a standard and there are multiple manufacturers of ZigBee chips.
Each one of those chips can have a slight variation to it.
ZigBee is supposed to work like a mesh network as Z-Wave does, but the difference is Z-Wave has total control of the chip manufacturing.
There is only one manufacturer that manufactures Z-Wave chips, which makes it very easy to make sure all Z-Wave devices connect and communicate together/properly with each other.
As you can imagine, since the ZigBee chips are manufactured based on a standard, with a lot of different manufacturers, there are slight variations in the chips and chip architecture, which makes ZigBee devices not always compatible with each other.
On top of that, with ZigBee, you have manufacturers adding their own firmware into the ZigBee chips and the ZigBee protocols that make it so certain devices on a ZigBee network can’t contact other ZigBee network devices without a hub.
Or, if they are different manufacturers, they won’t work.
That said, ZigBee is great and there are a ton of applications for it.
ZigBee is also used outside of home automation, including in healthcare applications, wireless monitoring applications, industrial applications, and so forth.
However, all those other applications have different chips and different architectures, and they're all meant to do something different.
So, the standardization for ZigBee is not there.
The two most common devices you probably know that have ZigBee in them are the Philips Hue device.
The Philips Hue Bridge has a ZigBee hub in it, and that turns a signal from the internet and cloud on Philips’s server into a ZigBee signal, and the ZigBee signal will then be transmitted to the Philips Hue light bulbs.
Those Philips Hue light bulbs are controlled with the ZigBee signal to turn on or off.
ZigBee is also available on the new Amazon Echo plus and what that does is provide a public functionality for the Amazon Echo Plus, where it can communicate directly with Philips Hue light bulbs.
Because they're a lot of different standards on a ZigBee platform, for future devices to connect to Amazon Alexa's plus hub, manufacturers manufacturing devices - whether it be a small light switch, a smart light bulb, or a smart plug - will need to put in the work, the effort, and the programming to make sure that it would be compatible with the Amazon Alexa Plus smart home hub.
That doesn't always happen!
So, the other home automation hubs that I’ve mentioned before, SmartThings and Wink, have Z-Wave chips.
They also have a ZigBee chip in them.
In terms of distance, both Z-Wave and ZigBee bee are fairly comparable in terms of how far the signals will travel.
ZigBee might have a little bit of an edge, but both of them about 100 ft. unobstructed work pretty well.
Now, if you've got concrete walls or brick walls, ZigBee and Z-Wave are going to decline very rapidly.
If that is the case, you’ll need to create extenders for your network.
You can do this for ZigBee and Z-Wave by adding another device, such as a light switch or plug-in device, or a specific repeater.
Typically, a Z-Wave network will work as a mash.
ZigBee will sometimes work as a mash.
It depends on if you have the same manufacturers, which means that a Philips Hue bulb can communicate to another Philips Hue bulb with the ZigBee Protocol.
However, you can't have another ZigBee manufacturer right now communicate with the Philips Hue bulbs in them back to the Hub.
You're limited by distance from the hub to the device you are trying to control.
This is something to keep in mind - that not all ZigBee devices repeat as Z-Wave devices do.
That’s an important caveat for you to understand.
How Nest Weave/Thread Works with Your Smart Home Devices
Nest advertises it as their own proprietary system.
However, Nest Thread and Nest Weave are really a ZigBee protocol or a ZigBee chipset.
The difference is that Nest has created their own proprietary way of creating ZigBee’s network so that all their devices connect and communicate with each other very well.
The downside of this is that those devices right now aren’t opened up to communicate with other non-Nest devices.
There are a lot of developers who don't necessarily want to commit to a standard that is owned and operated by Google because if they want to make changes, or it doesn't work for their specific device, they have to deal with Google to do that.
And, Google would be under no obligation to make the changes.
However, it does work very well for devices within the nest system.
If you see the Nest Connect that is used for a lock, that little device basically turns Wi-Fi into the ZigBee-Weave-Thread protocol for Nest and then communicates with the lock.
Because ZigBee is so much lower energy than Wi-Fi, it allows smart lock batteries to last a very long time.
ZigBee and Z-Wave, in terms of a smart lock, the batteries last about the same because they're both low energy standards for communication.
The Nest security system also works on the Thread protocol.
The actual hub for the Nest security system is outputting this Thread/Weave/ZigBee protocol to the other sensors within the network.
Those sensors are window or door sensors, and you just install them onto a wall and they work.
The range is about 100 to 150 feet for the Thread/Weave protocol.
It could go longer than that if you’re in an open field, for example.
If you were to need to repeat this Thread/Weave Nest protocol, you either need to have a device inside your house that is repeating it already, or you get a Nest Connect which basically converts Wi-Fi into this Thread protocol as well as repeats Thread commands throughout the network.
How Bluetooth Works with Your Smart Home Devices
The last protocol that I’m going to talk about is Bluetooth Low Energy or Bluetooth mesh networking.
Bluetooth has been around a long time just like Wi-Fi has.
Bluetooth is really good for low-energy devices.
You probably have used or had a Bluetooth speaker or Jambox or Bluetooth in your car.
I’m sure you're very familiar with how it works.
You turn the Bluetooth radio on your phone and you can control devices.
There are some devices right now that are using Bluetooth such as smart locks.
Another device that is using Bluetooth is the Flic smart button and which connects directly to your phone and then your phone interfaces with the internet and web servers to be able to control other devices that are connected through the web or through the Internet.
Bluetooth is good but once again there are a fair amount of different device standards so there's not a lot of devices that have mesh networking capabilities built in.
However, Bluetooth is a low-energy protocol so you can have devices like flic buttons controlling other devices and that device will last a year or two years because the battery usage is so low.
Bluetooth is great for sensors and things that you want to run on batteries.
But, the overall market hasn't created a standardized mash Bluetooth networking protocol that is widely adopted by a lot of other people.
So, typically what you see with a Bluetooth device is that the Bluetooth device will communicate directly with your home, or in some cases it will communicate with a home hub.
Bluetooth is also used in popular devices like Amazon Alexa.
You can communicate directly to the hub via Bluetooth so you can stream music from your phone (if you didn't want to go through the web services if you had a music store directly on your phone).
You can also use it on the majority of Amazon Alexa devices where you can stream directly from your phone to the Amazon device without the need to be connected to an internet network.
In terms of using it for home automation like light switches, I haven’t seen that yet.
It has primarily been used in smart speakers, buttons or sensors that need battery power for a long period of time, and smart locks that interface with your phone.
Which smart home automation protocol should you choose?
Comparing Wi-Fi, Z-Wave, ZigBee, and Bluetooth
In terms of what I would recommend for devices going forward in what protocols you should pick your devices around, I would say focus on Wi-Fi devices.
The reason for this is Wi-Fi will have the most interoperability with platforms and the ease of connection to an app and to the web service does not have a hub in between the Wi-Fi device and the cloud that you’re trying to communicate with.
Whereas, if you have a ZigBee, Z-Wave, or Bluetooth device (albeit not always with Bluetooth devices), those protocols need a hub that translates into the cloud protocols and the internet, which introduces another potential point of failure.
So, if you have something that is going to use power go with Wi-Fi.
If you have something that uses a battery, you can go with one of those other protocols, such as Z-Wave or ZigBee.
My personal preference is Z-Wave because of the reliability of the Z-Wave mesh network, the standardization of the chipset design, and the fact that the majority of Z-Wave devices will work together and repeat the signal flawlessly, which you don’t always have with ZigBee.
That isn’t to say that ZigBee doesn't have its place because it does.
But primarily with ZigBee, you’re looking at a device that is going to connect to a hub and then go to the cloud and web service, and then it's going to do its thing.
With all of these different protocols, I haven't really covered it yet, but I will draw you a picture (in words) of how devices work and interface with the internet.
So, for example, let’s say you have a Wi-Fi smart plug.
For a Wi-Fi smart plug, you're going to plug it into a device/power outlet and then you're going to put it in pairing mode.
Usually, you press the button on the side of the device for 5 or 10 seconds and that puts it into pairing mode.
Note, that every manufacturer is different.
That device is then sending out a Wi-Fi signal that your phone will pick up on the app.
Your phone connects to the device with the Wi-Fi signal and your phone is also connected to the Wi-Fi network in your home.
It recognizes the devices trying to connect and it recognizes your home network, and your phone, and the app basically acts as a bridge to give the Wi-Fi information to that smart outlet/smart plug.
The smart plug internally is then able to save your home Wi-Fi network.
Once that smart plug has the Wi-Fi network saved in it internally, it will then be able to communicate directly to your Wi-Fi router without the need of you being in the middle with a phone.
So that smart plug now has a connection to your Wi-Fi router and that Wi-Fi router has a connection to the cloud where all the smart device commands are stored and executed.
Let's say you have a Wi-Fi plug/smart switch that you want to turn on and off installed now - it is connected to your network.
You would go in your app and press on or press off.
That command goes to a cloud server on the internet and then that cloud server relays that information back down to your router in your home and then that router takes that command and converts it into Wi-Fi and it sends it to your smart switch to turn it on or off.
Likewise, that device will be sending information about its status.
When you have functionality such as a timer or additional functions, those functions are really just cloud service protocols, which are running up in the cloud that will then send a signal after one minute (if you set a timer for one minute) to turn on or off a device.
So the smarts aren't necessarily in the device itself, the smarts and all the different functionality and changes you can make are actually in the cloud itself, which is what's nice about Wi-Fi.
With Wi-Fi, developers can make a lot of changes in the cloud to add additional functionality to devices based on your routines, what you're doing, and how the use cases for a particular device are.
Then they’re able to implement that smart piece of things and just turn on and off the device without having to make a lot of device-level changes.
So that's pretty much how any of these different protocols work.
A device will send a signal to the cloud and the cloud will then send that signal back to your smart home device.
So, cell phone command, cloud, and then from the cloud to your router, and from your router to the device that you have installed in your home.
Now, if you have a Wi-Fi smart plug that is installed or works with Amazon Alexa, what happens there?
Well, then you say to Amazon Alexa, “Alexa, I would like to turn on or off whatever light switch you want to turn on or off”
Alexa takes that cloud command after you've connected your device as a skill in the Amazon Alexa app, and that cloud command then communicates with a specific manufacturer’s cloud and it says "I'm Alexa, I would like to turn off your light switch".
The manufacturer’s cloud then says “yes, you have access to us. We will let you control our device”.
The Alexa command is converted from Alexa voice into the manufacturer’s language of on and off.
The manufacturer of the device you have installed then sends that cloud command to your router and then to the device in your home.
The only difference with these devices regardless if they work on different protocols is that you might have a hub in between such as SmartThings or Wink.
I think that's a good tutorial and a good basis on the different smart home technologies and smart home automation protocols.
What I think you need to take away from this is, I would be Wi-Fi-centric first for the devices that will work with Wi-Fi.
That's where I would start because of the reliability, adaptability and future-proofing of Wi-Fi devices.
So, Wi-Fi first, then ZigBee or Z-Wave second depend on what use case you have.
Thirdly, Bluetooth for one-off devices that are connecting to your phone.