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Police seek Amazon Echo data in murder case

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Re: Police seek Amazon Echo data in murder case

#71

Post by cryptarch »

dannypgh wrote: post #29
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 think you're orders of magnitude off in marginal cost estimates for glacier users. Datacenters are being built out for a small number of commercial users (e.g. Amazon's core business) and the size of modern HDDs would lead me to estimate that storage is about free in a modern datacenter, the scarce resource is disk-time for read/write operations. That is, projects like glacier let Amazon sell disk that would have o…

I'm not in the datacenter business, so I've been conservative for lack of experience with storage at PB scale.

I've chosen to err on the side of estimating it to be more expensive, because I think that makes the end result more convincing:

30m is chump change for parties like Amazon, and in reality it'll cost significantly less. 1m might well do. Maybe it's less still. You could combine flagging users with flagging low-certainty or keyword-containing transcriptions.

Either way, you don't need collusion with intelligence parties, just an unscrupulous or naive exac at Amazon that thinks the data might be worth a lot for training future learning models. Of course the more sinister but legal reselling to government agencies is a financially attractive option as well.

Re: Police seek Amazon Echo data in murder case

#72

Post by matthewmacleod »

frik wrote: post #57
Flammy wrote: post #28

Earlier quoted context omitted.

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…

> computational costs alone of doing NLP The speech recognition part could run on a Pentium 133 in the nineties (Nuance software, Dragon naturally speaking), the Echo device has probably a more powerful CPU than that. The NLP part could run on the device as well, it's mainly a storage problem, you need dozens of GB, at least 32GB sdcard. Ideally only the search phrases would be sent to Google/Amazon/etc. That's also…

Speech recognition in the 90s was absolutely turd.

Re: Police seek Amazon Echo data in murder case

#73

Post by supergeek133 »

politician wrote: post #69

The device doesn't start listening when you say the wake word, the device is always listening . It's only the UX that responds when the presence of the wake word is detected. This means that the device is continuously monitoring the environment for the presence of the wake word we know about ("Alexa"). Can the device monitor for other words that trigger other UX sequences? Of course it can! Can Amazon deliver an OTA…

You're making quite a few assumptions.

1) The device is storing any amount of locally recorded audio. So far evidence says no.

2) Amazon would OTA all echos to upload everything it hears. So far evidence says this hasn't happened. It also likely won't because IMO security people monitor these devices more than anything else on the planet. Some I believe for good reasons, the others just want to play gotcha.

3) If 1 and 2 are true, Amazon keeps the data for an extended period of time.

Can we please not tinfoil hat the hell out of these devices like we do the rest of IoT sometimes?

Re: Police seek Amazon Echo data in murder case

#74

Post by Crito »

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…

>"The request of the police is nutty and indicative of not understanding the technology. Unless the murdered woman yelled out "Alexa {pause a little bit for wakeword recognition} Heeelp, my husband is killing me, call the police" or the husband asked "Alexa, how do I clean a bloody hottub", nothing material will be discovered."

The police often check search histories in murder investigations. Do you also suppose that is only useful if the victim googled "Help, my husband is murdering me!" ?

Maybe you should leave the policing to the police.

Re: Police seek Amazon Echo data in murder case

#75

Post by cryptarch »

coding123 wrote: post #63
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…

Actually you really only need to store about 1 month of data. If the police request something Amazon can lock the account from auto-deletion.

How so?

What about abduction cases, inside trading, tax fraud, drug and human smuggling? There it could help to have data from months ago, so any newly discovered targets instantly come with a bunch of evidence.

Re: Police seek Amazon Echo data in murder case

#76

Post by rz2k »

politician wrote: post #69

The device doesn't start listening when you say the wake word, the device is always listening . It's only the UX that responds when the presence of the wake word is detected. This means that the device is continuously monitoring the environment for the presence of the wake word we know about ("Alexa"). Can the device monitor for other words that trigger other UX sequences? Of course it can! Can Amazon deliver an OTA…

Should the police be able to enter any house with locks they can pick? I suppose that would educate people, too.

edit: I misread the comment as, "without a warrant"! Ugh

Re: Police seek Amazon Echo data in murder case

#77

Post by ajross »

gordyf wrote: post #62
Flammy wrote: post #28

Earlier quoted context omitted.

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…

No need for speculation: you can open the Alexa app and play back your own queries, audio and all. There's even a help section titled, "How do I delete Alexa voice recordings", which reads: "You can delete specific voice recordings associated with your account by going to History in Settings in the Alexa App, drilling down for a specific entry, and then tapping the delete button. Or, you can delete all voice recordin…

Once more though: that's just the audio flagged as a "query" by Amazon and stored as such. What about other stuff that gets uploaded prior to NLP & validation?

It's a serious question, and one that I think Amazon (and anyone else streaming audio to the cloud, Siri and Google Voice Search are only slightly less constrained) needs to have an answer for.

Re: Police seek Amazon Echo data in murder case

#78

Post by Marazan »

frik wrote: post #57
Flammy wrote: post #28

Earlier quoted context omitted.

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…

> computational costs alone of doing NLP The speech recognition part could run on a Pentium 133 in the nineties (Nuance software, Dragon naturally speaking), the Echo device has probably a more powerful CPU than that. The NLP part could run on the device as well, it's mainly a storage problem, you need dozens of GB, at least 32GB sdcard. Ideally only the search phrases would be sent to Google/Amazon/etc. That's also…

And that software in that era ha to be painstakibgly trained for each individual voice.

Echo "just works", and is clearly doing it by punting to the cloud.

Re: Police seek Amazon Echo data in murder case

#79

Post by politician »

supergeek133 wrote: post #64
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…

It doesn't matter, people will still tinfoil hat that the thing is listening and uploading everything they say. I had this exact same conversation with a number of people when the news came out about the Echo being in the Wynn Hotel in Vegas.

Given Stuxnet, your position seems dangerously naive.

There is really only one question: can this device be remotely modified to passively monitor a specific device in a way that is relatively undetectable to the end user?

If the answer is no, then fine. If the answer is yes, then what guarantee do you have that the ratchet of tyranny will not eventually deploy those capabilities? "I'm not hiding anything" is a poor response.

Re: Police seek Amazon Echo data in murder case

#80

Post by jbigelow76 »

FrancoDiaz wrote: post #24
Flammy wrote: post #3

I'm curious if the police will push this, as it could reveal how much voice information is actually stored. Amazon has declined to answer how much voice information is stored online[1] and how much if that is tied to your identity. We do know that Alexa stores a list of queries you've spoken, and you can "delete" these records, but it is unknown if this impacts the actual voice data behind them. [1] https://www.amazo…

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?

"Hey Alexa, how do I dispose of a dead body".

Maybe the cops are just hoping to get lucky.

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