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 https://www.zigbee2mqtt.io/advanced/zigbee/01_zigbee_network.html#finding-out-the-type-of-your-device
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+==Home automation without internet?==
+<!--
+'''Can I have home automation with less IoT?'''
+Yes.
+Some are entirely local, no internet at all.
+Some of those are even the pricy sold products.
+A lot of current products, and branding, makes the internet connectivity a selling point.
+I don't know why turning on your lights when you're on vacation is useful, but you ''can''.
+Also, you will end up with an account on yet another site, in a way you're not sure actually adheres to privacy law,
+because it's non-optional to get the thing to work.
+Also, you have no idea which continents are involved in controlling your lights.
+Also, you have the creeping suspicion that five years from now that company may not exist,
+so you may require emploiyment of hackers to, you know, ''turn on a light''.
+That said, most of these apps have thought a little further than you might assume.
+'''"Can't this just work without internet?""'''
+Yes, but depending on what your expectations are, guarantees are hard.
+Now, I am a nerd and electronics hobbyist, so I will delight in figuring out how to control it directly
+from my linux server after I reflash the firmware on the lightbulb.
+Most people? Want something that you plug in and ''just works'',
+after at most ten minutes of initial setup,
+They don't want to hear buzzwords to explain why it doesn't.
+This is one of a few things that gives a soft push design decisions towards "eh just put it on the internet".
+To be clear, none of those are a hard necessity.
+But this involves user experience exactly ''because'' things start depending on your home setup.
+'''Practical design decision #1: communicating with the thing.'''
+Local only is easy enough - remember there are light bulbs with an IR or RF remote.
+Have more than ''one'' of these, or a few of these, then all of them will react.
+Probably. You ''probably'' want something central to tell them apart and, possibly,
+be the thing that controls them.
+Even if you have that in hardware -- e.g. all the control signals in Philips Hue are local-only zigbee --
+you then still need to talk to ''that''.
+What does your phone speak that probably still works reliably 20 meters away?
+Wifi and Mobile connections.
+Also, when people ''really'' want control on their phone.
+And WiFi setups vary much more than you would think.
+Security features might e.g. isolate each device that attaches to the network
+from each other, because most laptops don't need to speak to each other anyway.
+But we did. So, security feature makes thing not work.
+Remember, people don't care about the buzzwords that make thing not work.
+They also don't really care about the vague instructions that ''maybe'' fix it.
+And you phone may not even be on the same wifi.
+And because people set up things weirdly sometimes,
+often without even realizing, and people do VPNs a lot now.
+In such setups, reaching hosts on the public internet is likeliest to work,
+for the really dumb practical reasons that people get really fussy when they can't reach their websites.
+(on the other hand, if all wifi clients are completely isolated from each other,
+most people won't even notice. Worst that will happend is that something like a chromecast doesn't work.)
+'''If phone control is a requirement, know that most phones are on the internet, but you won't know _how_'''
+You need some way to get to - and some way to prove it's really you.
+And yes, you should probably give up on local control.
+There are newer acronyms to do this (MQTT, WebRTC),
+but even those need to start by pointing at a specific server,
+and you ''could'' use dumb old web server requests perfectly well.
+So it turns out that if your design target is "everyone, in very varied networks",
+then putting a few servers around the world that do nothing more than receive and re-send
+"light on", "light off" is the easiest way to make it just work
+Are there other ways of doing it?
+Absolutely.
+One of the ways you may also be familiar with is to not have them connect to the unknown-quantity-to-them that is your WiFi,
+but to its own thing (it barely matters whether that's bluetooth, ZigBee, LoRa, or even actually just Wifi that is just its own network)
+People will balk at this, though, because that tends to mean you need a box that does nothing other than
+speaking to all the other things. That box will cost a little, that better be a nicely branded system for you
+to feel good about investing in that, but at the same that's exactly why they'll mark it up.
+So we roughly have:
+* Remote-to-device
+: perfectly fine for everything you have just one of.
+: If not, you need
+:: a lot of remotes
+:: to ensure a remote doesn't speak to every one of the thing in range
+::
+* Little box that talks to paired devices
+:: functionally almost equivalent to the next
+:: phone control
+::: from more than a few meters means bluetooth is out, and we already explained why wifi isn't a given to work.
+::: so probably still comes from the internet
+* Everything on the cloud
+:: functionally almost equivalent to the last
+So yes, for privacy and security standpoint, designing a fully local system
+with a few controls-everything remotes is probably better.
+But unlikely to happen - you don't buy things that way,
+and "doesn't work from your phone" is not a good selling point.
+It'll take some time before people listen
+and "because that's the best way to make it work always, and privately",
+if they ever do.
+---
+'''"So how do I keep my neighbor from being a jerk with my lights, and all of my other devices?"'''
+This often comes down to sharing a secret.
+You don't whisper passwords to your lightbulb, it's something generated and exchanged
+when you do whatever the setup looks like.
+If you're doing your own DIY, consider that the most basic variants are probably sensitive to replay attacks,
+so there's some nonces or asymmetry you want to be involved.
+---
+"How do I do automated setup?"
+So we've been playing with ESP8266 soft access points for a bit.
+Surely we can use something like that to configure them,
+and ''something'' like that is how various things I've tried
+seem to work.
+The last I tried had a "connect your phone to this temporary AP"
+as a fallback for if our primary way fails -- I'm assuming
+because that primary mode told it the wifi login via bluetooth,
+but bluetooth has less range.
+---
+'''"So how do I share this thing with my family?"'''
+You pray that the system you use thought of that, and thought it out well.
+You have zero control over how that app works, and no alternatives.
+And that's fine until the point you find something it could do, but doesn't.
+If based on a shared secret, you now need to share that.
+Because it probably means phone app, that is probably an account-level thing.
+With local-only control, that's harder to define.
+Particularly if there is no central control.
+Or maybe separately pair each device with multiple people. If it allows that.
+---
+And people want to do it from their phone.
+That usually means these things speak wifi, or bluetooth.
+Bluetooth can be direct, but also takes pairing to each device.
+That's fine for two radiators because that's some specific setup once anyway,
+though gets tedious if you want to make your home a ligtbulb disco.
+'''Practical design decision #2: Interface'''
+Even if you make it local-only, how do you interact with it?
+How do you deal with multiple people?
+It's nice that I can turn on the lights, but my housemate now relies on me to do that.
+(In fact there are plenty of products that don't care about that one)
+'''Practical design decision #3: Automation and interaction.'''
+Say I want it to blink whenever X happens.
+In a local-only setup, where does that run?  How do you administer that?
+On each device? Practical madness
+On the bridge? Doable.
+On the internet? Easier.
+Also people seem to like putting their living room to contain a microphone
+going out to the internet.
+That means you specific set it up on the internet to start with.
+'''Is this why these things aren't so hackable?'''
+It's a good part, in that the firmware on there will have a specific intent,
+which is communicating outside, and not listening to
+The firmware written for these things will want to be "",
+which
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