Z-Wave vs. Zigbee vs. Wi-Fi! Smart Home Basics: How To Pick The Right Protocol

today on the hookup I'm going to tell you more than you ever wanted to know about the three most common home automation communication protocols ZigBee z-wave and Wi-Fi here's a short list of the most popular communication protocols in the smart home industry as a new buyer picking which technology to use can be daunting and it may affect your perception of smart home products forever this video is going to focus primarily on the three main consumer smart home technologies that's ZigBee z-wave and Wi-Fi and to truly understand these technologies and their individual advantages i'm gonna divide up this video and look at these protocols through three different lenses science technology and business let's start by learning a little bit about the science even though there's a protocol that we specifically call radio frequency or RF 433 all smart-home communication protocols actually use radio frequencies radio frequencies are a type of electromagnetic radiation that sets the lowest energy side of the electromagnetic spectrum everything on this spectrum has two important attributes wavelength and frequency and multiplying the wavelength times the frequency gives you the speed at which the way its travel which is constant at the speed of light for everything on the electromagnetic spectrum since the speed is constant that means that if the wavelength is short the frequency then needs to be high and conversely if the wavelength is long it means that the frequency is low knowing the frequency of a wave matters for two reasons first frequency is directly related to the energy of the wave higher frequencies are higher energy frequency is measured in something that's called Hertz or cycles per second and in order to be able to more effectively compare the differences in frequency in this video I'm gonna express all of them in Giga Hertz the term electromagnetic radiation may sound scary and it might cause some people to worry but most of the radiation that we're exposed to on a daily basis is completely harmless radiation that we do need to be concerned about are the waves that are high enough energy to displace electrons in chemical bonds because this can cause both cell damage and mutations in DNA this dangerous radiation is called ionizing radiation and it starts in a part of the spectrum above visible light called ultraviolet the technologies we're going to talk about today are relatively low energy and have frequencies that range from about zero point four three three gigahertz to 2.4 gigahertz and for reference ionizing radiation specifically far ultraviolet begins at around 2.4 million gigahertz so arguments that these radio frequencies are gonna scramble our brains or give us cancer are unfounded and not backed by scientific research the second reason frequency is important is that it affects the ability to transmit data higher frequency means higher bandwidth or the ability to transfer more data in a shorter period of time but lower frequencies have lower attenuation when traveling through solids meaning they can pass through obstacles like walls without being blocked or losing their energy ZigBee Wi-Fi and Bluetooth all used the 2.4 5 gigahertz band where a z-wave uses the 0.9 gigahertz band this means that all things considered z-wave will have the greatest non-line of sight range between devices due to its lower frequency but it will sacrifice some bandwidth in order to do so currently the slower data transmission isn't that huge of a deal because messages being sent by these devices are relatively small but as these technologies make it into more high resolution sensors we may reach the limit of what z-wave frequency is capable of transmitting the last thing to talk about in this science section is frequency congestion sometimes refer to as interference when many devices are trying to communicate on the exact same frequency the data can get messy and the messages can get lost similar to trying to have a conversation with somebody in a crowded restaurant ZigBee Wi-Fi and Bluetooth all communicate on the 2.4 5 gigahertz band meaning that the potential for interference is high but in actuality they're able to tune to slightly different frequencies within that band called channels in order to reduce interference still even with different channels having too many devices constantly broadcasting on the same channel can lead to faults and drop messages which leads me into my next section about protocols and the technologies associated with each of these standards protocols are a defined set of rules for how devices communicate sometimes we refer to these protocols using terms like light weight or error tolerant based on their specific rule set an example of a human protocol is when you order something at a drive-thru and the cashier repeats your entire order to you at the end this would be an example of a fault-tolerant protocol because you confirm that your entire order was received and no parts of the message were lost but this protocol not only takes more time but it would also break down if I spoke a different language than the cashier and we only knew the names of the foods in our own languages so how does this apply to smart home devices z-wave is a proprietary technology run by a company called Sigma designs if your device says z-wave on it it means that it's licensed by Sigma designs and the manufacturer had to adhere to strict rules about the protocol and language to ensure maximum compatibility between devices Sigma even exercises control over who can produce z-wave chips which are all produced by silicon labs the upside to this total control is that the protocol is extremely standardized and you can always be sure that your z-wave devices will be able to communicate with your ziwei hub regardless of the brand but the downside is that Sigma designs is able to charge more for these chips and for the licensing which results in a higher cost per device ZigBee on the other hand is an open wireless standard meaning individual companies can implement their own products without the strict set of rules like those enforced by z-wave as a result just like ordering from a drive-thru in a different language even though every ZigBee hub will be able to hear every Sigma device it might not be able to understand what that device is saying for example I have these two Yazidi sensors that are designed to be used with a to use igby hub a Samsung smartthings hub can easily discover these ZigBee devices but since the protocol is not standardized the hub has no idea what type of device they are or what information they're trying to convey these slight differences in implementation of ZigBee devices can cause even larger issues due to the way that they form the communication network both ZigBee and z-wave forms something that's called a mesh network where they can extend the range of the signal by relaying information from one device to the next in order to make it back to the hub best-case scenario is that this relay process extends the devices range while only introducing a minor delay or latency but as the number of relays or hops increases the delay can become very noticeable in an effort to reduce this latency and increase customer satisfaction z-wave limits devices to a maximum of four hops while ZigBee hasn't implemented any limit because of the need to relay messages to the hub you may also need to intentionally place ZigBee or z-wave devices in intermediate locations in order to extend the range of your mesh and it's also important to understand that these mesh devices must have constant power so we're talking about things like light bulbs plugs and switches that will act as nodes and not battery-powered sensors further complicating things if you have ZigBee devices from multiple manufacturers in your smart home they might not be able to communicate with each other meaning they might need to form separate mesh networks which can actually end up interfering with each other causing dropped or lost signals reliability and fault tolerance are also worth discussing when considering these different technologies like I said before as radio frequency bands become more congested the likelihood of data loss increases dramatically ZigBee and z-wave are relatively lightweight protocols when compared to Wi-Fi meaning there's less handshaking data redundancy and confirmation in their communication most of the time this lightweight protocol represents a huge benefit since battery-powered ZigBee or z-wave devices will transmit significantly less data than a Wi-Fi device and will therefore have a much longer battery life but in terms of fault tolerance they are unquestionably worse it's unlikely that a purely z-wave network would ever have enough traffic to cause issues but if there were another device communicating or emitting a signal around that point 9 gigahertz band there could theoretically be a whole network breakdown Wi-Fi is a completely different animal when compared to ZigBee and z-wave the Wireless 802 11 n standard that most smart devices use is an open protocol that any device maker can implement and it's got a strict set of rules for how your device needs to communicate with your network unlike the mesh networks of ZigBee and z-wave Wi-Fi devices communicate directly with the closest access point and will not relay information between devices the reason why if I can get away with this connection method is because you ostensibly already have or at least want to have a good Wi-Fi connection everywhere in your house if you're thinking about starting a smart home and you have spotty Wi-Fi coverage in your house I'd recommend tackling that issue first before jumping into home automation it's going to save you a lot of headaches later even with dozens of devices communicating with a centralized access point your Wi-Fi network is actually extremely orderly and your access points to an amazing job telling each device to wait their turn in order to reduce signal noise in addition Wi-Fi devices communicate on your network using the tcp/ip protocol which is designed with fault tolerance in mind each tcp/ip communication employs a specific handshake and data validation in order to ensure that no parts of the transmission are lost the downside of fault tolerance is that it requires significantly more data transmission which requires more power a battery-powered Wi-Fi censor will drain its batter is significantly faster than a comparable ZigBee or z-wave sensor and the last difference in technology that I want to talk about is how these devices are ultimately controlled let's compare the communication methods of a Wi-Fi door sensor versus a ZigBee or z-wave door sensor in this example let's say that I want to be notified on my phone whenever a door opens for a ZigBee your z-wave system the contact sensor pulls apart the device then wakes up and begins its transmission if the device is too far away from the hub to communicate directly with it it will contact its closest powered neighbor and send the state of the door that device will then relay that information through the mesh until it arrives at the hub let's say in this case that hub is a Samsung smartthings hub that hub will then send the information over the Internet to the Samsung smartthings cloud server and that server which is connected to the Samsung app on my phone will then send a message to my phone via a push notification in the Wi-Fi device like this to your door sensor the device will send its message directly to the wireless access point which will then be routed to the to your cloud server which is connected to my to you app causing a push notification to be sent to my phone this Wi-Fi communication sounds much more efficient but in my opinion it's where I think ZigBee and z-wave devices actually have the greatest advantage over Wi-Fi it's true that Wi-Fi devices that use the popular esp8266 chip are able to be flashed with custom firmware to keep their traffic local but this method is not something that the typical user is going to be comfortable with and it's not something that would be applicable to every device type but since ZigBee and z-wave sensors communicate directly with a hub the user can decide which hub they want to utilize in order to control their smart home in my example I showed the smartthings hub because it's the most popular entry-level hub on the market but since it's a loud bass system it doesn't represent any increase in reliability or privacy over a Wi-Fi sensor however locally controlled in process hubs like the hubba tat elevation are available or even better home assistant can add ZigBee or z-wave compatibility with a USB dongle in these instances cloud services can be cut completely out of the picture which will increase reliability and privacy while decreasing security risk significantly the last consideration for these standards is a topic that I'm significantly less familiar with and that's business contracts and economics z-wave is a completely proprietary system and as I understand it there's not a whole lot of development being done by other companies if you're a manufacturer and you want your device to speak z-wave you pay them a fee you get a module and you plug it into your device the z-wave Alliance then tests out your device to make sure it adheres to the strict z-wave standard and allows you to print the z-wave certified logo on your packaging as a result z-wave devices tend to be more expensive than comparable ZigBee or Wi-Fi devices and even though their compatibility with the z-wave hub is guaranteed I'm not sure what business decisions are being made to ensure that z-wave radios will be included in the next generation of hubs as new technologies emerge for instance in 2019 Apple Google Amazon and the ZigBee Alliance among others joined forces on a project that they're calling connected home over IP which will undoubtedly shape the future of smart home devices z-wave was notably not listed in this huge collaboration of companies which could possibly be disastrous for them in the future the good news is that your z-wave devices aren't likely to just stop working all the sudden but there could come a time in the not-too-distant future when companies move away from the z-wave standard which could in turn affect the range and reliability of your existing z-wave mesh network as you upgrade your new devices to this chip standard if you watch this video thinking it would help you decide on a technology and use in your smart home but ended up more indecisive than ever here's the most condensed advice that I can offer choose z-wave if you're going to buy a lot of products at once put them all over your house and you don't mind spending a little bit more on each device the more z-wave products you have the better your mesh will be and the more reliable your network becomes if you're just getting started the Samsung smartthings hub is easy to and has a lot of information about how to get set up but if you value your privacy it is absolutely worth looking into a local solution like hub ITAT or home assistant to act as your z-wave hub ZigBee does sound good in theory because the products are cheap and diverse but you should be aware that not all ZigBee devices can communicate with each other and some proprietary ZigBee networks like philips hue for example will form separate meshes that could end up interfering with your main ZigBee mesh in my personal opinion unless you have a specific reason to buy ZigBee right now it's probably best to go a different way until the connected over IP product reaches maturity Wi-Fi devices can be utilized in two very different ways you can buy Wi-Fi products and use them right out of the box with no hub to connect to your Google home or Amazon echo this is by far the easiest and most user-friendly implementation of smart home products but it's also the least secure and that's not to say that there is an eminent risk just that it's the most exposed way of adding a smart device to your home network since each device is going to be communicating directly with the cloud service the second and best way to use Wi-Fi devices is in a local communication only setup as I mentioned earlier many of the Wi-Fi devices on the market today utilize the esp8266 chip which allows more advanced users to replace the factory cloud firmware with custom firmware that uses local communication in processing like MQTT and home assistant for devices where custom firmware as possible local Wi-Fi setups are the most fault tolerant reliable and responsive solution given the right networking equipment I purposely didn't address some of the possible hacks on ZigBee and z-wave systems because I think the likelihood of them occurring would be similar to you being eaten by a circus lion but I am going to talk about them in an upcoming video about smart door locks anyways thank you so much to my awesome patrons over at patreon for continuing to support my channel if you're interested in supporting my channel please check out the links down in the description if you enjoyed this video please hit that like button and consider subscribing and as always thanks for watching the hook-up

Channel: The Hook Up

Views: 276,707

Rating: 4.9384112 out of 5

Keywords: home assistant, hassio, home automation, hass.io, smart home, diy, electronics, arduino, esp8266, nodemcu, wemos d1, automation

Id: v8-VNIQQiQE

Length: 15min 33sec (933 seconds)

Published: Wed Feb 12 2020

Reddit Comments

[u/mversion]

I love this guy and highly recommend you follow his channel. Well-spoken, well-researched, a lot of passion and very to the point.

If only he did more NodeRed videos... you can never have enough NodeRed videos.

[u/PufffSmokeySmoke]

Great video. I just got started in implementing my own Z-wave and Zigbee hubs and this video really helped. One thing I noticed however, with Z-Wave you mention that:

“You can always be sure that your Z-Wave devices will be able to communicate with your Z-wave hub.”

It is my understanding that Z-Wave is localized to different regions, and uses different frequencies depending on your location. For example, Z-wave products for North America use a different frequency than Z-wave in Europe and are not compatible with one another. Just something to note if you’re buying products online!

[u/WizrdOfSpeedAndTime]

One of the things I love about Home Assistant is that I can glue all of these protocols together. It has also created a lot of network congestion with Zigbee and WiFi because of my hodgepodge approach.

[u/jds013]

The remarks about the proprietary nature of Z-Wave aren't quite up to date: see https://www.silabs.com/wireless/z-wave

And Silicon Labs (which controls Z-Wave) also makes Zigbee processors.

Both protocols have healthy futures.

[u/DarkFlare]

I’m unsure why zwave is preferred? I’m a big fan of zigbee due to the cheap price and standards, I use the conbee as a hub and home assistant to tie it all together. Are the negatives of zigbee that standards aren’t enforced and it’s on the same range as WiFi?

Zigbee has such a wide variety of devices and it’s cheap! I’m not sure why it isn’t recommended. I also noticed that sonoff now have a zigbee sonoff basic!

[u/WizrdOfSpeedAndTime]

I think I will slowly replace my Zigbee stuff with WiFi and Z-Wave. I already have enough Z-Wave that the network is robust. Also I have have come to the conclusion that my family will never stop turning off the switch to the Zigbee devices.

[u/guice666]

His videos have gotten me into building into wifi devices, instead of zigbee or zwave. And got me to cleaning up our wifi so that we can do that!

Our alarm system, doors, windows, etc will use a local low band devices (right now, we're on a Qolsys IQ 2 panel and devices). But for home automation, I do prefer to use local capable wifi devices (e.g. tp-link).

I don't think Z-Wave standards are being enforced very well. e.g. I tried Ring door sensors which is certified as Z-Wave+, but they don't work. They kept showing up as "thermostat" on our IQ Panel, also certified Z-Wave+. This shit turned me off from Z-Wave devices.

Hues are our only Zigbee devices. We don't plan to expand this out to any other manu.

This video pretty much convinced me to go wifi: https://www.youtube.com/watch?v=2fqg2D02UKY. The Hook Up has merely confirmed my decision.

[u/kigmatzomat]

Overall very good. I only had two minor nitpicks.

The first is that zwave manufacturers can use novel commands on their devices as long as it is truly a new functionality outside the spec zwave spec. Meaning on/off must follow the spec but if this was a zwave air mattress they could add a new "pressure" parameter.

The second is he glossed over the zigbee LL/HA/3.0. He got the point across that zigbees don't all play nice but didn't explain what buyers should look for to avoid issues

[u/scatteringlargesse]

I really like the Shelly hardware because I can tuck it behind existing light switches, is there anything like that but with Z Wave or Zigbee?