Police seek Amazon Echo data in murder case

Post by jsjohnst » Tue, Dec 27, 2016, 5:28 PM UTC

MichaelGG wrote: post #12

bkbridge wrote: post #2

Alexa only waits for the wake word "Alexa." It would cost more money than God in hardware to store every thing Alexa ever heard. She saves you're requests. And shows you those request in the Alexa App. And you can also delete it if you wish. There is no data for the police to have, because beyond requests, there is no data. Unless someone knows more about this than Amazon is telling us?

A year of audio at 32kbps (more than enough for speech) is only 120GB. That's only a couple bucks of month on S3 -- at retail pricing. So it's technically and financially feasible to store everything if Amazon wanted to.

Post by pavel_lishin » Tue, Dec 27, 2016, 5:29 PM UTC

notlisted wrote: post #48

Alexa listens only to the words after the wake word. What's more it doesn't capture more than 10-12s past the wake word. If you have a device you can check this yourself (Alexa, One Mississippi, Two Mississippi…). It's actually hard to get it to capture this much. Take a breath or pause to long and capture stops sooner. The request of the police is nutty and indicative of not understanding the technology. Unless the…

Post by GordonS » Tue, Dec 27, 2016, 5:33 PM UTC

tclancy wrote: post #33

cryptarch wrote: post #13

Earlier quoted context omitted.

It would cost about $30m a year if you tailor the system to flagging specific data for storage and don't naively store every moment (e.g. you scrap silent moments and use VBR encoding). Storing a year's worth of 96kbps audio costs 380GB. If you don't record silence and you assume the people around an Alexa are only speaking for at most 4 hours a day on average, that goes down to 76GB a year. So if you then assume 5m…

I really like the math here, but isn't this a bit pointless? The system wants to parse meaning from audio; storing just the text it parsed is a lot smaller. Store just the text and whatever machine learning score of how probable the text is correctly parsed and that sounds like something prosecutors would love to bring into court: "Please read this line and let's see what score you get . . . "

Post by frik » Tue, Dec 27, 2016, 5:36 PM UTC

Flammy wrote: post #28

FrancoDiaz wrote: post #24

Earlier quoted context omitted.

Wait a minute, we'd already know if Alexa was recording everything by the network traffic that obviously has already been sniffed. We can assume that Amazon is storing every "Alex,..." query that you've ever done. So what is there to know?

We know they are streaming it to do all the NLP in the cloud. This is obvious from the computational costs alone of doing NLP. The important question here is "What happens to the audio data streamed to the cloud, a few seconds AFTER the query has been identified (or not identified) and the results sent back to the Alexa device?" The nieve assumption is "all audio data is deleted after processing". The reality is that…

Post by jc4p » Tue, Dec 27, 2016, 5:41 PM UTC

notlisted wrote: post #48

Alexa listens only to the words after the wake word. What's more it doesn't capture more than 10-12s past the wake word. If you have a device you can check this yourself (Alexa, One Mississippi, Two Mississippi…). It's actually hard to get it to capture this much. Take a breath or pause to long and capture stops sooner. The request of the police is nutty and indicative of not understanding the technology. Unless the…