Explanation of the different connection types?

Is there a website or otherwise that talks to how all the different technologies around home automation communicate?

Like I know z-wave talks on a low wi-fi frequency and requires a USB device to enable communication directly with the openhab server and if it takes more than 4 hops to talk to a device will fail.

Something similar for ZigBee and Amazon and Google, etc that when you have one of these devices how do they talk and to where? I continue to get confused like with Alexa, it’s Wi-Fi based, but it has to connect to Amazon and then you have to also add it to openhab but what is it communicating on and to in the end if it has to talk to Amazon? Just an example.



You will have to research each technology individually. Looking at the wikipedia article for each will probably be sufficient. There are literally hundreds of home automation “standards” so one website that talks about them all is not feasible.

I can say off the top of my head

  • zwave is not WiFi but it is wireless and therefore requires a USB controller
  • ZigBee is not WiFi but it is wireless and therefore requires a USB coordinator
  • Google Assistant and Alexa both require WiFi
Echo Device    <->    Amazon Cloud     <-> openHAB

The Echo talks to the Amazon Cloud and only the Amazon Cloud. openHAB talks to the Echo by talking to the Amazon Cloud.

So is it safe to say that “Amazon Cloud” is a hub? And OpenHAB is a HUB. So if I have OpenHAB and an Echo on premise, technically I have two separate hubs in the picture? If so what happens when the internet is down? Do I get access to my functions thru voice or do I have to switch to the openHAB mobile app?

How does thing like a Wi-Fi Smart Switch that supports Alexa work? Is it safe to say it’s an “Alexa” device? Kind of like a Z-Wave labeled device? So I need something like an Echo to use it? What if I just have OpenHAB? Can I not use the switch then?

Way you describe it above, it sounds like Echo talks to the Amazon Cloud and the cloud talks to openHAB. Not sure if it’s cloud openhab or on premise.

Also sounds like depending on responses to the above, if I want to m be able to utilize my setup entirely without the cloud, I need to use Z-Wave type devices and if the network goes down then OpenHAB would still work without voice capabilities?

Sorry for all the questions.



No. A hub is a device on your local network that bridges connections between different technologies. openHAB would be a hub. Vera, Wink, and Hue Hub are hubs. Amazon Cloud is a service that allows openHAB to talk to Echos.

While having more than one hub is not uncommon, Echo is not a hub.

The Echo will not work and oh will not be able to talk to Alexa or the Echo.


The company that makes it made an agreement with Amazon to allow Alexa to find and control it. It depends on how it works as to how Alexa finds and controls it. Some may work locally. Others may use cloud service to cloud service.

You can say that but it is meaningless in an openHAB context.

No, because I know of no device that ONLY works with Alexa and requires Alexa. Maybe it’s better to say it’s Alexa compatible. Zwave is the technology the device uses.

No, it’s a WiFi switch so you just need WiFi and the app that the vendor is to control it.

If there is a binding that supports it then you just need openHAB. But beware, WiFi doesn’t really tell you anything about compatibility with OH. Every brand has their own API, and some of them are encrypted.

I’m not sure. I don’t use echos.

It didn’t have to be zwave. Zigbee, hue, and and hundreds more do not require internet access to work. You need to do the research into how it works before you buy it.