Z-wave or Zigbee. The future?

Hello,

I am purchasing a Smartthings hub and now choosing devices for the system.
Please correct me if I am wrong, but there seems to be logic in purchasing devices that run on the same protocol/language in that the more devices on the same mesh, the more robust, and furthest range and ultimately the best product for the user. Therefore, I am thinking that choosing one mesh for the whole house makes sense.

I am struggling to choose which protocol to use. Based on research it seems that Z-wave has a lot of products, generally is geared for the smaller application, and is produced by one sole manufacturer who is then resold to others. Zigbee seems to be a great option too for its openness, products, and reliability.

That said, I want to put my eggs into the basket that will allow for the most future expansion and possibilities to work with other systems (i.e. HomeKit, etc.).

Please let me know if you thing one system is better than another and what the future looks like for these two protocols.

I will certainly base my choice on the feedback!
Thank you, John

Generally speaking I would stick with zwave. While zigbee has some nice features, ultimately there is a proprietary nature to it. Example: Smarthing’s things don’t work on other systems and vise versa. There are a few exceptions but you can’t just take all your zigbee devices to another control system and be sure they will work. Zwave has a much more universal compatibility with each other.

Great site for zwave devices.

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Both are good protocols, with different pluses and minuses. See the following article in the community created wiki:

http://thingsthataresmart.wiki/index.php?title=Z-wave_versus_Zigbee

Some people prefer to stick with one protocol, many, including myself, chose SmartThings specifically because it supported multiple protocols and therefore I could select the best device for each use case. It’s not that difficult, or expensive, to build a strong backbone for both Zigbee and Z wave in a typical size house. :sunglasses:

And here is a more general FAQ that also includes WIFi.

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As far as where to buy, shop around. Prices vary a lot and sales are fairly common. :sunglasses:

See the following for some of the more popular online retailers.

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Thank you very much for your input. I really appreciate your time and will probably move toward Z-Wave products. Regarding the proprietary nature of of Zigbee - It’s a little counter-intuitive to me.

As I understand it, the Zigbee standard is a consortium of manufacturers that essential regulate the technical details of the language and equipment. Whereas Z-wave is a single company owned standard and are the only ones making the chip and then sell it to other branding companies. If that is correct, its strange to me that Zigbee would be more restrictive as there are more companies who could benefit from the sales of products. Since Z-wave is a single source of supply, it seems like there would be less likelihood of future expansion into other companies.

Regardless, it seem that Z-wave is more widely distributed throughout the home market. One think I like about Zigbee though is that they seem to be small with smaller batteries.
Is that generally true?

Thank you for the link and I will scour the website!

Zigbee Interoperability

It’s easy to get confused about this and many people explain it in a way that can make it sound more confusing, although it isn’t really.

In part because it is a group, the zigbee alliance allows for a lot of customization within the standard. Different manufacturers can add their own encoding. This can in fact improve the security of zigbee, which is one reason it has been popular for security systems.

Zigbee historically handled interoperability through “profiles.” A device could be certified as using the vanilla “zigbee home automation” profile or the “zigbee medical” profile or the “zigbee green energy profile,” and if it is one of those profiles, it meant it would be broadcasting standard messages with the standard addressing scheme. So far so good, right? In theory, any coordinator using a specific profile (like smartthings uses the zigbee home automation profile) should be able to talk to any device using the same profile.

Fingerprints

But then there is one more twist. Every zigbee device has its own “fingerprint” which lists the device class, The manufacturer, the model, and the specific command clusters that it can process.

In order for a coordinator to be able to talk to a device, it has to know which clusters it uses. Many Coordinators, including SmartThings, use a common library for this. If they recognize the device’s fingerprint at the time that it joins the network, then they know which device handler to use to talk to it.

The problem arises because the fingerprints can be slightly different just because they include the manufacturer information. The brand and model.

So there are two ways for a Coordinator to handle the situation when it doesn’t recognize the specific fingerprint. It might just use the supported command cluster information, which is also available from the device.

But most home automation systems don’t do that. Again, this can be considered a security measure. Instead, they look up the fingerprint, and if they don’t already have that on file, they just list the device as a generic thing and you can’t really do anything with it.

This is what will happen if you try to join, for example, a SmartThings branded zigbee sensor to wink or Iris. Even though these all use the same zigbee profile, the coordinator says “I don’t know who you are” and sort of stops there.

Smartthings is very unusual in that it allows the customer to assign the device to a specific device type handler (DTH) after joining or even write their own DTH for the system to use.

This is why ST customers can use so many different zigbee devices from different manufacturers. As long as the device is using the zigbee home automation profile, you can capture its fingerprint at the time that it pairs to the smartthings hub, and then create a device handler for it.

Since it’s ZHA certified, it’s going to use the standard command clusters. It’s just a matter of properly introducing it to the SmartThings hub. :sunglasses:

Prebuilt systems

The fingerprint issue doesn’t matter to systems which are sold in kits of preselected devices. This is how most DIY security systems are sold, for example. In those cases the Coordinator will be preloaded with the fingerprints for those devices. And again, some people consider it a security advantage if the coordinator cannot be joining to any devices not on the preapproved list.

But for home automation systems, where people tend to occasionally add entirely new devices of a device class they’ve never had before, being able to buy from multiple manufacturers gives you a lot more flexibility. And that’s what SmartThings delivers.

Zigbee 3.0

The next generation of zigbee, 3.0, is going to combine many of the profiles into one, but it isn’t backwards compatible in that way you might expect, and it still doesn’t address the fingerprint issue. So it will improve inter-operability, but not open it up completely.

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Yes, although the newest generation of zwave, zwave plus, has both reduced size and improved battery life over previous generations.

Thank you!
I just learned a ton about the two protocols. I think I will push toward Z-wave but not have reservations on a Zigbee if the product fits my needs better.

Thank you very much for the detailed answer and letting me feel good about moving forward. I appreciate your time.
John

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I have a mixture of both, as long as the product work well with smartthings, why should we bother about the communication protocol?

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The main reason I went with 100% zwave is that it gives me flexibility to try/switch to new controllers without a loss of investment. It’s too early in the Smart Home game to feel trapped.

Several threads on this forum are about people looking for alternatives to ST and every single one of those threads have people who would try something else but have put too much money into zigbee devices. This stuff is expensive and you don’t want to feel trapped/regret.

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I never knew the technical reason behind why zigbee rarely could be used between different controllers. Thanks for the info. I can’t help to think that the many companies don’t mind that you can’t use their units on other systems. It’s a pretty common strategy for companies. I try to avoid those situations as much as possible.

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That’s true, a lot of companies making zigbee products don’t really intend to sell individual devices. They sell a set of devices with the controller. It works for them.

Zigbee is an open standard. The Iris motion/contact can be used on multiple controllers. The zwave contact and motion sensors are giant compared to zigbees. Some older (first gen Iris and the zigbee you get from comcast) are tied to the controllers.

Zwave has a limit of 255ish, but in practice is about half, mostly due to the limited number of jumps in the mesh. I am well over 100 devices already.

I run mixed, not worried if I need to jump since all the devices I have are open standard ones.

The reality is these devices need to last 2-3 years, because new protocols will make them obsolete and I will probably end up replacing many of them. I did choose zwave light switches, for price and hopefully long lived backwards compatibility. They are the devices I would not want to replace.

Depends on the brand. The zwave is usually bigger, but there are some brands which have really worked on miniaturizing

This is a Fibaro zwave motion sensor. Build as the “worlds smallest Z wave motion sensor” it’s only 1 3/4 inch across. (But it will cost around $70.)

This is a smartthings brand zigbee motion sensor. It’s 2" wide and costs about $40, although there are some competitors that typically listed at around 20.

In this case, it’s the Z wave sensor which is smaller. :wink:

But the Fibaro is expensive. If you’re looking at inexpensive Z wave motion sensors, no question, many of them are relatively very big (in this case almost 3.5" tall) compared to a similarly priced zigbee version.

Fibaro motion size 1.732 inches around

Iris Motion size: 1.6 inches across X 1.7 inches tall X 0.70 inches deep

The iris has a nice corner mount cut out too. The fibaro’s are nice, but the price and the flashing of color made me hesitate. Even the iris in a dark room the flash is pretty bright, had to tape over it in the bedroom.

Edit: Form factor is important, main reason I stick with the Iris. Fast small and blend in nicely.

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There’s a very good reason. Both Zigbee and Z-Wave are mesh networks. If half of your devices are Zigbee and another half is Z-Wave, you’re not taking full advantage of mesh topology and also expose yourself to RF interference in both 900 MHz (Z-Wave) and 2.4 GHz (Zigbee) bands.

The article omits two important advantages of Z-Wave over Zigbee HA profile:

  1. Z-Wave natively supports multiple controllers. Zigbee HA does not.
  2. Z-Wave has a standard mechanism for switching from one controller to another (controller shift). Zigbee HA does not.

Generally, device compatibility is still better in Z-Wave world. Chances that your Z-Wave controller will be compatible with generic Z-Wave switch, dimmer, motion or contact sensor are much higher than with any Zigbee controller I’ve seen.

Good points!

It’s a wiki–fix it. :wink:

(And multiple controller features are not well supported in SmartThings, for what that’s worth)

I see it in diff way, by using both zwave and zigbee, you can have 2 mesh networks and you can get the best product from market in term of price and functionality.

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I have a mix of z-wave, zigbee, WiFi, Rf, infared… It’s very difficult to just stick with one standard without missing out all the goodies out there. Most of my lights and relays are zwave. Motion sensors, contact sensors, smart bulbs are zigbee. I wouldn’t worry too much about future standard. Most likely it will be something else completely new so in the mean time I Just buy what I think is best for my situation.

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