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Alexa not working? Here's what happens in the cloud when your smart home device fails

When a smart home device fails, it's frustrating. We wanted to find out what goes on in the cloud behind the scenes. We got exclusive answers from the engineers at Amazon and Leviton. What they told us showcased the interplay between IT and home reality.
Written by David Gewirtz, Senior Contributing Editor

Image: Leviton

In some ways, I think my dad had it easier than me. If my mom told him the bedroom light wasn't working, there were just two possibilities: the bulb had blown or the power was out. It was simple.

But this is 2022, and nothing is simple. Let's say your wife tells you, as my wife did, that the bedroom light isn't working. What could be the problem? Could it be the bulb? Could it be the bulb's connection to the hub? Could it be the smart light switch? Could it be the Wi-Fi connection between the smart light switch and the router?

Could the router's 2.4Ghz connection have failed? Could the 5Ghz connection have somehow tried to connect to the switch, which only talks to the 2.4Ghz band? Could our broadband connection be down? Could the Alexa services be down? Could the cloud service at the bulb vendor be down? Could the cloud service at the smart light switch vendor be down?

Could the phone app that talks to the smart switch be out of date? Could my iPhone's connection to ... oh, for cryin' out loud! It's just a light!

Go ahead...say it. Smart home. Could any two words be more mocking of modern life?

True story


Recently, our bedroom light stopped working. The problem, it turned out, was an Alexa skill. When opening the skill up in the Alexa app, this message was displayed, "The link between accounts has expired. To continue using My Leviton with Alexa, click Enable to Use and link your accounts again."

We have an old non-smart floor lamp in the bedroom that has three non-smart dimmable LED bulbs. We control it with a Leviton DW3HL-1BW Decora smart plug. This plug is different from most smart plugs because it has a dimmer. Most smart plugs just support on and off. But the Leviton plug lets you set any brightness you want. At about $40, it's more expensive than most smart plugs, but the dimming feature makes it worth it.

Here's how these things work. An app on the phone talks to the smart switch. This is a Leviton-provided app. To make Alexa control that switch, there's a skill, which is launched in the Alexa app. Think of the skill as the glue that connects the switch to the Alexa network. In order to authenticate that Alexa is allowed to control the switch, the skill talks to the app's cloud-based component and verifies our account.

So you have the local Alexa and the local switch. You also have the Alexa cloud and the switch vendor's cloud. All these things need to handshake and work together. As the message showed, that link expired.

Also: Best smart plug: Putting the app in appliances

But here's the thing. You don't want your light switch to expire. You want to set it up once and just use your light switch. If we have to reset all our IoT devices every three months, or whatever, that will make the whole smart home idea crazy-making.

Clearly, something was going on. I wanted to know exactly what, and why. I wanted to know the behind the scenes story.

Leviton, Established 1906

Let's be clear. Leviton isn't one of these new smart home startups that may or may not have staying power. Leviton is home wiring royalty. The company has been around for more than 100 years. It was started by Isidor Leviton, who designed a screw-in light bulb housing for Thomas Edison's first commercial bulb. Remember the pull-chain lamp holder your grandma had? That was designed by Leviton. Not the company, the dude.

Fast forward to 2022 and my account link error message. I wanted to know what goes on at the vendor when something like this happens. Was it a cybersecurity or account issue? Does this happen on a regular basis? Is there a regular expiration date or period? Does Leviton find that adding IoT control, and in particular, linking to smart assistants, increases the challenges in providing smart devices to customers? Enquiring minds and all that.

So I reached out to Greg Rhoades, Director of Marketing at Leviton, who was kind enough to provide a detailed answer. 

Here's what he told me:

At Leviton, we take great pride in our dedicated product, app, and cloud engineering teams, as well as our tech support and customer service team members -- all of whom work tirelessly to ensure Leviton customers receive the experience they have come to expect from our company and products. Of course, we are disappointed to hear of instances when this expectation is not met, and we devote our time and resources to help resolve any issues that may arise and to improve our products and experiences moving forward.

With regard to the situation you described in which a Decora Smart Voice Dimmer stopped responding to voice commands, we have found this to be neither a cybersecurity issue nor a specific product issue. In our experience, this is an Alexa cloud issue that, at times, we have seen impact a limited number of user accounts and subsequently the devices they may have tied to the account. The vast majority of our skill users do not experience this issue.

Leviton is constantly making improvements and working to continually develop and refine our products and services based on customer feedback and industry best practices. We pride ourselves in maintaining our smart home development teams out of our Leviton Innovation Center in New Orleans -- including our dedicated app and cloud engineering teams -- rather than outsourcing this work. We also have our own "Works With" team and close relationships with technical partners at Amazon, Google, Apple, Samsung and more to support the array of smart home features in our portfolio.

Leviton has been in the home automation space for decades providing smart lighting solutions. As with any business, there are always challenges but generally, we don't see significant product issues associated with linking across the three voice assistants we support and have regular direct meetings with those teams to continually improve our connectivity.

Rhoades later reached out to me with an additional clarification:

To clarify, we are not saying there is an issue with the Amazon Alexa service. The issue we are encountering is a problem in the cloud which involves the linking of My Leviton accounts to Amazon. When accounts are not linked, Amazon Alexa cannot communicate with the Decora Smart device to control the lights. We are working with Amazon to resolve this issue. We have only seen this impact a limited number of users. The vast majority of our skill users do not experience this issue.

You have to know my next stop, then, is going to be Amazon.

Also: Best smart hub: Control your smart home

Asking the Alexa teams

I shared the Skill error message and Rhoades' response with the folks at Amazon. I asked them the same set of questions about cybersecurity, authentication, account maintenance and such.

Samantha VanHoef, an Amazon spokesperson, dug into this for me. In fact, she researched this for me right in the middle of a move, so big thanks to Samantha for adding my little bit of research homework to her already challenging schedule. After talking to the smart home team and skills team at Amazon, she shared this:

The experience you had is related to the expiration of an account-linking token, which links the customer's account at a third-party vendor with the customer's Alexa account. This expiration isn't unique to smart home devices or Alexa, but is industry standard for linked accounts. An account-linking token could expire for various reasons, including if the customer doesn't use an account for a certain period of time (set by the third-party vendor) or if their account credentials change.

When this token expires, the customer's account with the third-party vendor becomes unlinked from the customer's Alexa account. The notice you saw on the skill detail page is Alexa's mechanism to notify customers of what to do next, and help them re-link their accounts. Let me know if you'd like me to dig deeper with the team for more technical information on the Alexa side, but there isn't a lot more we know because the specifics of each token are set by the third-party vendors themselves.

Final thoughts

I left it here because, among other things, we (me, Leviton, and Amazon) had already exchanged 33 messages (not counting the internal emails at Leviton and Amazon) chasing this down. Essentially, the issue came about because of some level of authentication rot, because the connection between the systems grew old.

Also: The best home automation system 

This problem may actually flag an interesting authentication challenge that companies like Amazon and Leviton have to look into. Take, for example, Samantha's phrase, "if the customer doesn't use an account for a certain period of time." That's interesting, because we use the bedroom light daily, but it's probably been a good year or more since we logged into the Leviton app to set it up.

From our perspective, we use the product daily. From the authentication handshaking perspective, the last auth request was over a year old. But even if IoT authentication tokens are out of date, companies like Leviton and Amazon can't default to requiring re-authentication. What if this hadn't been my bedroom lamp, but one at an elderly relative's house? How many of us techies set up smart home devices for our friends and families, and then leave them to their own devices (pun intended)?

Even though skills and apps are relatively easy to set up, the various linkages are baffling to non-techies. It's hard enough to get these things set up correctly, but when they fail, many users are simply left with unusable devices (at least until they can convince someone with tech skills to come over, have a fresh baked cookie, and fix the problem). I can't speak for all techies, but "will work for fresh baked goods" has been a successful policy for me for many years. My biggest score was a home baked apple crumb pie.

Seriously, though. The Leviton and Amazon products -- and by extension all smart home devices -- are wonderful when they work. But usage patterns (like account authentication) that work in the IT world don't translate logically to the home automation space. Hopefully, we'll see the friction taken out of these systems over the next few years.

In the meantime, a big shoutout of thanks to the folks at Leviton and Amazon for letting us see behind the scenes and taking the time to explain what really happens when a light won't turn on in 2022.

How many panicked calls have you gotten from relatives when their smart homes turn not-so-smart? How many smart devices do you have in your home? Let us know in the comments below.

You can follow my day-to-day project updates on social media. Be sure to follow me on Twitter at @DavidGewirtz, on Facebook at Facebook.com/DavidGewirtz, on Instagram at Instagram.com/DavidGewirtz, and on YouTube at YouTube.com/DavidGewirtzTV.

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