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A few weeks ago, I started wondering how much of my smart home would keep working during an internet outage.
I have devices from several manufacturers around the house: an Ecobee Smart Thermostat Premium, Kasa smart plugs and a power strip, Tapo lights and a motion sensor, a Wyze Cam v4 recording to a microSD card, a Sonos Era 100, and Apple Home tying some of it together.
Everything works well enough during a normal day. That doesn’t tell me much about how independent any of it really is.
So I disconnected my router from the internet while leaving the router and Wi-Fi network running. Then I went around the house and tried the things I normally do.
The results made me think differently about which smart-home features are actually valuable.
First, I Left the Wi-Fi Running
There are two ways to simulate an internet outage, and they produce very different results.
Unplugging the router takes down the local network along with the internet connection. That wasn’t what I wanted to test.
Instead, I disconnected the internet connection and left my router powered on. My devices could still communicate over the home network, but they couldn’t reach services outside the house.
This is also a reasonably good simulation of a typical ISP outage. Your modem or internet connection can fail while your router continues broadcasting Wi-Fi.
With that done, I started with the thermostat.
The Ecobee Kept Doing Its Main Job
My Ecobee Smart Thermostat Premium continued functioning as a thermostat.
I could walk over to it, change the temperature, and control the HVAC system from the touchscreen. Losing the internet didn’t leave me without heat or air conditioning.
That sounds obvious, but it’s an important requirement for something controlling essential equipment in the house.
The connected features are where an outage becomes noticeable. Anything requiring Ecobee’s servers or information from the internet naturally has nowhere to go while the connection is down.
The experience left me more comfortable with having a smart thermostat controlling the HVAC system. Even if Ecobee’s online services or my own internet connection have a problem, the thermostat on the wall remains useful.
For something as important as heating and cooling, that’s exactly how I want it to behave.
Kasa Smart Plugs Were More Interesting
I also have Kasa smart plugs and a Kasa smart power strip around the house.
These are the kinds of devices that can make cloud dependence confusing because several different things happen when you tap a button in an app. Some commands can involve devices on your local network, while remote control and certain connected features require internet access.
The physical controls continued to give me a simple fallback during the outage. I could still turn the connected equipment on and off at the plug itself.
That may seem like a low bar, but I’ve become much more interested in physical controls as I’ve added smart devices to the house. I don’t want to dig through apps to turn on an outlet when something goes wrong.
The test also reinforced something I’d recommend doing with any smart plug: check your schedules and automations before you actually need them during an outage. A schedule stored and executed locally has a much better chance of surviving connectivity problems than an action that needs an outside service.
Tapo Lights and the Motion Sensor Show Why Local Automations Matter
Lighting is where an internet outage can go from interesting to irritating very quickly.
I use Tapo lights along with a Tapo motion sensor for some lighting around the house. Normally I don’t think about the path a command takes. I walk into the room and expect the light to turn on.
During the outage, I paid attention to which controls and automations continued to behave normally and which depended on services outside my network.
That distinction matters more to me now when setting up automations.
A motion sensor turning on a nearby light is exactly the kind of automation that should happen inside the house. Sending that simple event through the internet adds another potential point of failure to something that happens dozens of times a week.
It also changes how I look at hubs. A hub can sound like unnecessary extra hardware when you’re buying your first smart bulb. Once you have sensors, lights, thermostats and other equipment working together, having something inside the house capable of coordinating them starts making a lot more sense.
Apple Home Held the Setup Together Better Than I Expected
Apple Home is the main smart-home platform I use, with a home hub providing the local center of the system.
This was one of the parts of the test I was most interested in.
Apple’s architecture allows supported accessories to communicate within the home network, and a HomePod or Apple TV can operate as the home hub. Matter accessories can also communicate locally over IP, while Thread devices use a Thread Border Router to reach the rest of the home network.
With the internet disconnected, I could see why that architecture matters.
Remote access was obviously out of the picture because my house had no connection to the outside world. Internet services were unavailable as well. Local smart-home functions had a much better chance of continuing because the controller and accessories were still inside the same functioning network.
It made my home hub feel less like another box required for setup and more like an actual piece of infrastructure.
Matter Makes More Sense During an Outage
I’ve written a lot about Matter since starting Wired Dwelling, but an internet outage makes one of its advantages much easier to appreciate.
Matter uses IP networking and supports local communication between controllers and accessories.
For basic smart-home commands, that can eliminate an unnecessary trip to a manufacturer’s cloud server.
A Matter light and its controller can be sitting 20 feet apart. Having a server somewhere else involved every time that light needs to turn on never made much technical sense.
Matter still leaves manufacturers room to provide their own additional features. Energy history, firmware downloads, cloud storage and other services may need an internet connection depending on the product.
During normal use, you may never notice which path is being used. An outage exposes it very quickly.
It has made local Matter support a more important consideration for me when I’m choosing new smart-home equipment.
The Wyze Cam v4 Made a Strong Case for Local Storage
The device I was most curious about was my Wyze Cam v4.
I have a microSD card installed for local recording, which gives the camera somewhere inside the house to store video.
That matters during an internet outage.
Cloud-dependent camera features require connectivity, and viewing a camera remotely isn’t possible when there’s no path into the house. Local recording gives the camera useful capability even when an outside service can’t be reached.
This is one of the reasons I’ve become a big supporter of cameras with local storage.
Cloud recording has real advantages. If somebody steals or destroys a camera, footage stored elsewhere may survive. It also makes accessing recordings away from home convenient.
I still want the microSD slot.
A security camera is one of the last devices I want becoming dramatically less useful because my ISP is having a problem.
After using the Wyze Cam v4 with local storage, I consider a local recording option a significant advantage when comparing cameras.
Sonos Showed the Limits of a Connected Speaker
My Sonos Era 100 was another useful test because speakers depend heavily on where their audio is coming from.
The speaker itself doesn’t lose its ability to play audio simply because an internet connection disappears. Sources and features that require an online service obviously become unavailable.
Streaming services are the clearest example. If the music lives on a server outside your house, the speaker needs a way to reach it.
Voice assistants can run into similar limitations depending on the request and the service involved.
This wasn’t particularly surprising, but it highlighted how many different definitions of “working” can apply to a smart device.
A thermostat can lose every online feature and still perform most of its essential job. A streaming speaker can remain completely functional hardware while losing access to the source of most of the music you normally play through it.
What I Learned From Disconnecting the House
The biggest surprise was how much functionality can remain available when the local network stays alive.
Before doing this, an “internet outage” and a “Wi-Fi outage” were easy to lump together. They’re very different events in a smart home.
The router matters even when the internet doesn’t work.
So do hubs, local storage, Thread Border Routers and devices capable of communicating locally. They’re easy to overlook because none of them is particularly exciting when everything is online.
They become much more valuable when something fails.
I also came away with more appreciation for physical controls. Every smart plug should still be easy to operate as a plug. A thermostat should always work from the wall. Lights should have a practical fallback.
Smart-home equipment is going into ordinary parts of the house that people expect to work for years. Resilience deserves more attention than it usually gets.
You Can Run the Same Test at Home
If you have a reasonably large smart-home setup, this is worth trying.
Leave your router and local Wi-Fi network running, then disconnect the router’s internet/WAN connection. Don’t factory-reset anything or start changing network settings you aren’t familiar with.
Once the internet is disconnected, use your house normally.
Try your lights. Trigger motion sensors. Change the thermostat. Check your cameras. Run your usual automations. Open your smart-home app and see which accessories respond. Try your speakers.
Pay attention to failures, but also pay attention to what works.
Reconnect the internet when you’re finished and verify that everything comes back online normally.
It’s a simple test, and you’ll probably learn more about the architecture of your smart home in 15 minutes than you did while setting most of it up.
What I’ll Look for When Buying Smart-Home Devices Now
Local operation is going much higher on my list.
For cameras, I want local storage whenever it’s practical. For important devices such as thermostats, I want full physical control without an account or internet connection getting in the way. For lights, plugs and sensors, local communication and locally executed automations are increasingly appealing.
Matter and Thread are useful here because they give manufacturers standardized ways to build local connectivity into products, although I’ll continue looking at the actual capabilities of each device rather than assuming a Matter logo answers every question.
I’m also less interested in adding another manufacturer’s app to my phone just because a product has a clever feature.
Once you’ve accumulated enough smart-home equipment, reliability becomes more valuable than novelty.
My internet connection eventually came back into the equation and the house returned to normal. The useful part of the experiment was seeing how much of the house never really needed it in the first place.
That’s something I’ll be paying much closer attention to from now on.