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Amazon to hand over Echo audio from alleged murder after defendant consents

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Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#182
post #62

Earlier quoted context omitted.

> The audio Amazon receives is from only-just-barely-before the wakeword up to and through the command or timeout expiration. I wonder, how on earth do you know that, that you are able to dismiss it with such confidence as a non-issue. That's the problem with proprietary systems (proprietary always-on microphones at that). I would be surprised if they weren't actually listening and analysing and storing data from the…

You can just watch the network traffic from the device to see when it is streaming audio. Now this obviously doesn't rule out the device saving stuff locally, but plenty of people have verified that it does generally only send lots of data to the server when you have just asked it to wake up.

It is possible it's doing local voice recognition on all audio, and just sending the text in their payloads. If the content is encrypted, there's no way for any network snooping to determine what they're sending.

Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#183

Earlier quoted context omitted.

Yes, exactly this. They could easily just TTS what you are saying, save the text, and send it together with the rest of the info when you say "Alexa". Thus only sending information when you say "Alexa" but managing to upload all your conversations. I would be very surprised if they aren't doing something like this. The power of analysing which products you talk about in your home more often, what kind of stuff you co…

It is very well known that the actually speech processing happens on the cloud. To deploy a whole cloud voice recognition system if you have distributed network with TTS capability on the device would be quite a lot of redundant work to go through. However, with that said, unless they do certificate pinning on their device the answer to that is to MITM the device and snoop on the traffic. If they do certificate pinni…

Any amount of text - when compressed - would be dwarfed by a number of things that may also be included in the data exchange, such as a software update. There's no way to conclude that a larger exchange of data means a big exchange of a week's worth of text.

Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#184

Earlier quoted context omitted.

I'm not certain there exists nothing to reveal. Is there a technical limitation of the system that prevents or avoids recording of "non-'Alexa'" audio? Or do I just trust Amazon when they say their alway-on device only records when triggered with the magic word? As I think about it, I'd ask the same regarding the voice-controllable phone in my pocket. FWIW, I don't trust the devices, because their operations are out…

From looking at the internals, there's technically nothing that prevents uploading all audio constantly to AWS. Practically, it would be unwieldy to have 10,000,000 devices sending audio to 10,000,000 audio decoding and processes 24 hours a day nonstop. You'd also see a huge bandwidth hit at your ISP, which would certainly kill future adoptions if the word got out.

I see a lot of people in this thread saying that's not possible, so here's the math:

As given by squarefoot, you can record human voice at 1200 bit/sec = 150 bytes/sec. A day is 86400 seconds, assume people are talking (generously) 10% of the day, so 8640 seconds * 150 bytes = 1.3 megabytes per day uploaded to Amazon.

Does anyone doubt that _the company that runs AWS_ is incapable of dealing with barely a megabyte per device per day?

Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#185

Earlier quoted context omitted.

To spell it out, that's extremely unlikely, it's not impossible . Just very, very costly.

Easy answer. They may not have to send the audio. They could transcribe it locally at the client, encrypt, and send text to store on the server. Consider that almost a decade ago, programs like dragon naturally speaking could be run on a relatively inexpensive laptop. It's entirely possible that a dedicated device like the echo could do this today. EDIT: Original reply sounded too definitive

It's not transcribed locally at the client except for the wake word.

Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#186

Earlier quoted context omitted.

So record the audio 24/7 and compress and send once an hour? Once a day? Or eliminate empty space first. The files wouldn't be that big

Totally possible. As an example, Codec2 used in ham-radio applications can send pretty decent voice audio at a few kilobit/s or less, and it keeps sounding perfectly understandable even at 1.2 kbit/s like this short sample: http://www.rowetel.com/downloads/codec2/hts1a_1200.wav More information here: http://www.rowetel.com/?page_id=452

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Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#187

Earlier quoted context omitted.

I'm not certain there exists nothing to reveal. Is there a technical limitation of the system that prevents or avoids recording of "non-'Alexa'" audio? Or do I just trust Amazon when they say their alway-on device only records when triggered with the magic word? As I think about it, I'd ask the same regarding the voice-controllable phone in my pocket. FWIW, I don't trust the devices, because their operations are out…

From looking at the internals, there's technically nothing that prevents uploading all audio constantly to AWS. Practically, it would be unwieldy to have 10,000,000 devices sending audio to 10,000,000 audio decoding and processes 24 hours a day nonstop. You'd also see a huge bandwidth hit at your ISP, which would certainly kill future adoptions if the word got out.

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Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#188

Earlier quoted context omitted.

The main thing I'm taking away from this is that, if I ever find myself getting murdered, I'll just keep shouting "Alexa" as a last ditch attempt at getting justice from beyond the grave. Can't hurt.

I was thinking about this -- I'm too afraid to try it, but if I said, "Alexa call 911", does that functionality exist? Is there a skill I can install that would let me say something like, "Alexa start recording audio to the cloud"?

"Alexa call 911" doesn't work (at least currently) and it looks like it's against Amazon's rules to try and create a skill that calls emergency services: https://developer.amazon.com/public/solutions/alexa/alexa-sk...

Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#189

How is echo audio data substantially different than something like a tape recorder that was live in the man's home? What about a cell phone that was on a call at the time of the alleged murder? I definitely understand wanting to ensure reasonable privacy for users, but to me it feels an awful lot of a stretch to say that the echo is off-limits in this case.

If the EULA says that Amazon's listening and you agree to be okay with that, there's little you can argue against it, other than saying don't use such devices.

Re: Amazon to hand over Echo audio from alleged murder after defendant consents

#190

Earlier quoted context omitted.

How do you know they don't 1. Listen all the time 2. Use a small neural network on the device to detect when a voice is present 3. Collect this data into one zip file, then send the file when the user says "Alexa", or anything remotely close. They could even put a size limit on the data upload to reduce the variance to prevent you from ever testing whether they do this. Or, they could simply transcribe the audio on t…

Yes, exactly this. They could easily just TTS what you are saying, save the text, and send it together with the rest of the info when you say "Alexa". Thus only sending information when you say "Alexa" but managing to upload all your conversations. I would be very surprised if they aren't doing something like this. The power of analysing which products you talk about in your home more often, what kind of stuff you co…

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