
Activate this ‘bracelet of silence,’ and Alexa can’t eavesdrop - rmason
https://www.nytimes.com/2020/02/14/technology/alexa-jamming-bracelet-privacy-armor.html
======
justinjlynn
Yikes, please don't do or encourage using these in public - there are many
accessibility devices (hearing aids, cochlear implants, etc.) which depend on
MEMS microphones to function. You could inadvertently make the world much
worse for people who already have a difficult time of things. Imagine carting
a cellular and WiFi and bluetooth jammer around outside of a Faraday cage -
it's insanely irresponsible and inconsiderate.

~~~
tomohawk
The people making the world worse are the ones putting microphones everywhere
and eavesdropping on everyone by streaming all that audio back to their server
farms.

~~~
stubish
I think deaf people might disagree, and would likely make the world much worse
for people wearing these in public by beating the crap out of them.

~~~
tyingq
Maybe dogs as well.

------
jonny383
The fact that this article exists actually makes me sad.

When did we as a society give up our privacy for such a small amount of
convenience? Or has it been gradually chipped away until we have reached this
point?

I feel sorry for my children and the future in which they are going to live
in. I also feel a sense of shame for participating in a society that has
normalised these things.

Sorry kids. We got greedy. We boiled the planet and normalised blanket spying
for profits.

~~~
discordianfish
The fact that this article exists actually makes me sad as well.

But because Alexa isn't eavesdropping on us and believing this is the tech
equivalent of antivaxxers: "If you don't believe it, you're part of the
conspiracy"

~~~
falcolas
Do you recall the “ghost” incident, where Alexa believed she was being asked
to laugh? What was Alexa hearing in your everyday life to believe that not
only the trigger word, but the whole phrase was being said aloud?

Also, do you recall the fix? They _remotely changed_ the activation phrase
that triggered the laugh.

Do you recall the Google home devices with a minor physical flaw that caused
the pucks to record and transmit everything?

Do you recall how these recordings are given to third parties to evaluate to
improve the quality of the service?

I guess what I’m trying to say is that we don’t know when or if these devices
are recording us. Yes, the same is true with our phones as well (though this
bracelet from the article would work on them too). It might not be out of
malice, but its safe to say that we as the customers have no real idea of how
much they hear.

~~~
bestnameever
> Also, do you recall the fix? They remotely changed the activation phrase
> that triggered the laugh.

I don't see that as a big deal as the data is likely always sent to a remote
server for parsing and processing.

~~~
evan_
It (supposedly) listens for the wake word locally and doesn’t transmit until
it hears it.

~~~
bestnameever
sure but that doesn't change. the wake word doesn't change. the only thing
that changed was the phrase which caused the laugh.

~~~
falcolas
The wake word can, at least with Alexa, be changed remotely. There are limited
options, at least today.

Also, the firmware on these devices is remotely updatable. Even when you can't
today, you may be able to tomorrow.

------
bscphil
> A large, somewhat ungainly white cuff with spiky transducers, the bracelet
> has 24 speakers that emit ultrasonic signals when the wearer turns it on.
> The sound is imperceptible to most ears, with the possible exception of
> young people and dogs, but nearby microphones will detect the high-frequency
> sound instead of other noises.

This is surely not actually effective against a wide range of well designed,
real world microphones, and definitely not against something designed to
surreptitiously record you. Strikes me as more of a gimmick than anything
else.

Full disclosure: I don't have any always-on microphones in my house, and
probably never will, so I probably qualify as some kind of techno-skeptic.

~~~
hinkley
I know more than a couple of older people who can still hear very high pitched
whines from electrical equipment. The “only children and dogs” is some bad
statistics.

Also houses have dogs or kids. Or both. It’s a thing.

~~~
xzel
I’m a bit older than average and these types of things and noises drive me
crazy. I can’t even be near some old CRT screens due to the pitch they emit
(especially bad with old CCTV monitors).

~~~
hinkley
I may have lost a little at the high end or electronics have gotten better
filters, but I used to grumpily stomp into the next room to turn off the tv or
the VCR because it was bugging me.

There was a story a few years back about stores getting rid of young loiterers
by playing these tones, then later on kids setting ringtones or alerts on
their phones so that the teacher wouldn’t get mad that their phones were on.
Guess what? A lot of surprised 15 year olds had their phones confiscated by
disgruntled 40 year old teachers who could damn well hear the ringtones.

~~~
JonathonW
The TV noise you used to hear is gone because CRTs are gone-- it comes from
the flyback tranformer in the TV, which had a propensity to resonate at the
TV's horizontal scanning frequency (somewhere in the ballpark of 15.7 kHz, the
exact frequency depending on whether your TV was NTSC or PAL).

I had a "I haven't heard that in ages" moment over the summer; was in some
shop in the UK that had a CRT showing their CCTV cameras and could hear the
thing well before I could see it. Apparently my high-end hearing's still
decent.

~~~
andrewzah
CRTs are almost gone; they’re still highly sought after in the smashbros
community. :-) IIRC trinitrons are the most highly desired.

Due to the shortage, a "crt vault" was created. [0]

I remember visiting multiple thrift stores ~2 years ago to collect them. The
most I had was 6 I think, but I ended up giving them to other players. Here's
an example of what they look like at tournaments [1]

[0]:
[https://old.reddit.com/r/smashbros/comments/3dzqd9/to_those_...](https://old.reddit.com/r/smashbros/comments/3dzqd9/to_those_who_enjoyed_smash_at_evo_please_thank/)

[1]:
[https://www.youtube.com/watch?v=j_WBBeXzUcQ](https://www.youtube.com/watch?v=j_WBBeXzUcQ)

------
archi42
This only fights a symptom, the real problem is that these smart assistants
need to stream the input to a company. Of course I understand that this allows
for better recognition, but while I personally would like to have a well-
working voice assistant, I personally do not want to have someone else
(potentially) listening in on me (if others care less, that's perfectly fine).

Maybe I'll find some time to setup a self-hosted voice assistant.
Recommendations?

~~~
dijksterhuis
Mycroft turned up on HN a while back [0]. Think there’s another one that was
posted in the last few months, but can’t find the link.

Pretty sure you can hook it up to Mozilla DeepSpeech for completely offline
stuff.

0: [https://mycroft-ai.gitbook.io/docs/](https://mycroft-ai.gitbook.io/docs/)

~~~
dillonmckay
Is Mycroft self-hosted?

It seems like you have to register to create an account?

There is also a ‘skills’ marketplace, so not sure how private it is.

~~~
dijksterhuis
Can run in a docker container, on Linux etc etc.

You do need to pair it with an account to activate basic skills, but:

> By default, Mycroft will not store your usage data or keep any recordings of
> your voice

[https://mycroft-ai.gitbook.io/docs/using-mycroft-
ai/pairing-...](https://mycroft-ai.gitbook.io/docs/using-mycroft-ai/pairing-
your-device)

~~~
dillonmckay
So, why is that part not self-hosted?

~~~
archi42
I checked on mycroft, and the last comment (by the CTO) on
[https://community.mycroft.ai/t/easiest-way-to-use-mycroft-
co...](https://community.mycroft.ai/t/easiest-way-to-use-mycroft-completely-
offline/3741/22) says:

"It is a bit of a chicken-and-the-egg situation, but I don’t think there is a
strong case for creating an easy offline setup before the core components are
ready. It is close, but I suspect it will be at least another year before we
(the open source community) have all those pieces ready."

However, their backend seems to be on GitHub.

------
fxtentacle
If this actually works, then the Alexa engineers forgot to add an analog pre-
filter to their ADC. And most likely, adding digital filtering through one of
those horrible unsupervised software updates will also circumvent it.

Plus I'd say they chose by far the easiest target. A squirrel's sneezing is
enough to confuse Alexa beyond recognition.

In my personal experience, the Google and Baidu speech to text algorithms are
much more resilient against background noise.

~~~
Anarch157a
In my conspiracy theorist opinion, they didn't forget. They left it out on
purpose, so the mic can detect ultrasound embeded on tv transmissions to track
which tv shows and comercials you're watching[0].

[0][https://arstechnica.com/tech-policy/2015/11/beware-of-ads-
th...](https://arstechnica.com/tech-policy/2015/11/beware-of-ads-that-use-
inaudible-sound-to-link-your-phone-tv-tablet-and-pc/)

~~~
mxuribe
I thought it was to allow/support Luthor-to-Superman communications? I'm
joking of course. I agree with you actually...When others think something is
due to incompetence, i feel these companies are nothing more than sneaky and
shady.

------
Havoc
>The sound is imperceptible to most ears, with the possible exception of young
people and dogs

That seems pretty cruel

------
neonate
[https://archive.md/E7Ez7](https://archive.md/E7Ez7)

------
ThePhysicist
This is a cool and super creative project, but I think the simpler solution
would be to not buy a device that listens to all of your conversations at
home, or at least switch it off when not needed. And if you're exposed to such
a device as a guest in someone else's home or office, kindly ask the owner to
switch it off and explain why you think it's not good to have such a device
listening to all conversations you're having.

It would also not be so hard to make such devices more privacy-friendly e.g.
by giving users are clearer indication of when they're listening to you and
when they transfers data to the cloud. I think Amazon already allows you to
review and download all audio conversations they have from you (in theory this
is mandatory in the EU).

~~~
Wowfunhappy
Every phone has a microphone, and it too is always on. Are you going to ask
everyone to turn off their phone?

~~~
Thriptic
This is what I don't understand. Everyone runs around terrified of these smart
speakers but have no problem talking around their phones which have mics,
their computers which have mics, other devices which have mics, CCTV cameras
which are ubiquitous, etc

Do people realistically think attackers are going to start burning zero days
against these things to listen to the average Joe's kitchen conversations or
bedroom chatter? What is the threat model here?

~~~
ThePhysicist
You confuse privacy with security I think. Smart home assistants might be
secure but they are not privacy-friendly, that's a difference.

~~~
Thriptic
I follow, but what exactly is the real privacy threat here? If we look at an
echo for instance:

* The device is hardwired to light up whenever it is listening so you can't be eavesdropped on without some indicator.

* The device only transmits when it is in listening mode. This has been validated independently by multiple people.

* The device has a mute function (granted, software).

* The device can be registered under a bogus account.

* You can turn off all phone call capabilities / external listening capabilities.

* You can pihole it so it won't reach back to Amazon's ad services.

* You can delete any conversation you don't want stored manually, including one click deleting your entire history.

* You can have all content automatically deleted after X days.

So what exactly are people concerned about? Out of all the convos someone
could have, a negative one just happens to probabilistically be recorded, you
don't notice, and within 90 days someone in law enforcement or entity X
figures it out and uses it against you? Someone at Amazon decides to look
through your stored conversations and sees you turn on the lights at 5 PM each
day?

I'm not saying there are 0 privacy implications with this device, as any
device that has a mic and can record remotely has privacy implications. I just
feel like the level of angst generated by smart speakers isn't warranted in
the grander scheme of things.

~~~
ThePhysicist
Well it’s totally fine to have that opinion and use those devices, personally
I wouldn’t though.

Privacy is a niche topic right now and it might stay that way, but I think
more and more people will become concerned about what large companies know
about them. Each individual service and datapoint is not very critical as you
say, combining data from multiple sources and using the data in unexpected
ways can quickly reveal very intimate things about a person though. Companies
like Amazon, Google and FB do not mainly use your data to “improve your
experience”, they use it to nudge you into behavioral patterns that benefit
their business model (i.e. look at more ads or buy more stuff). I doesn’t take
so much imagination to see how this might harm you e.g. because you develop
unhealthy spending habits or waste large amounts of time on social media. And
the more data a company has about you, the easier it is for them to manipulate
you. So for me it’s not about defending against an unknown attacker, it’s
defending against companies using my data to manipulate me, which they might
do even if they keep my data very, very secure.

------
nico_h
I can’t figure out why we are not switching to active listening devices , star
trek badge style instead of enduring this permanent surveillance thing.

We’re reaching the point where it becomes feasible in terms of electronics
density and battery efficiency.

~~~
ghaff
That's sort of what an Apple Watch is, isn't it? You have to press the button
to activate Siri.

------
tareqak
I am interested in the Reflectacles, but I’ve already bought glasses this
year. Is there a way to coat / paint an existing glasses frame with a material
that would interfere with IR cameras and visible light cameras?

------
bitcurious
This sounds like a device designed to torture animals. If someone brought this
into my house and turned it on around my dog I would probably ask them to
leave.

~~~
A4ET8a8uTh0
Likewise. And I am sympathetic to the idea, but this is the wrong way to go
about it. Too many innocent bystanders.

It does reignite the debate over what is acceptable. Cost of putting
microphone in anything is negligible. Connection to internet in many things is
assumed so even if microphone is unused, it could be turned on with an update.

Then again, my social circle met yesterday and they have multiple devices
controlled by voice. It didn't stop anyone from saying things that would not
look good if broadcast in public. It is weird, how easy it is to forget about
it. Probably because you think it is your space. I would not dream of messing
with their devices. I am a guest. I opted to be there.

I tried to think about it rationally. I can't give them too much shit. Between
me and my wife, we have 8 devices in house now that have microphones and/or
cameras in.

Ok google is off. Siri is off on phone, but on watch it is activated by a
button, so there is semblance of control.

------
znpy
So now One has to opt out from being spied upon, and wear a piece of hardware
too?

------
Wowfunhappy
I could see this being used in e.g. the white house, just in case a foreign
adversary has somehow managed to slip a bug in there. Or maybe because the
president insists on using an unsecured Android phone.

------
eyegor
Link to the actual work:
[http://sandlab.cs.uchicago.edu/jammer/](http://sandlab.cs.uchicago.edu/jammer/)

------
steventhedev
How is this not filtered out by a lowpass filter? Wouldn't this only block the
ultrasonic beeps they embed in ads?

~~~
QuarterDuplex
Assuming you mean a digital lowpass filter; this won't work. The ultrasonic
input is saturating the microphone. In this situation, no amount of digital
filters can recover the desired signal (the speech). If there was a physical
low pass filter (not sure if these exist) that was placed over the microphone,
that would work

------
unnouinceput
Walls and ladders, nothing more. Pretty sure a bigger ladder will be
discovered very soon following this

~~~
eyegor
Nah, it's physically jamming the spectrum. Unless someone can come up with a
microphone that only resonates in the audible range, this technique will
always work. It's akin to pointing a really bright light at a camera.

~~~
unnouinceput
While really white bright will jam your eyes too, an ultrasound will not jam
your ear, hence this is actually easier to overcome. Just use dumb microphone,
that will cut frequencies over 10Kz and have the unintended secondary effect
that Alexa will be even cheaper.

------
_-___________-_
Why not just have similar device adjacent to the device that you're worried
might eavesdrop on you?

~~~
DyslexicAtheist
why not have any eavesdropping devices in the first place. when somebody
invites me around, I usually ask if they own one of these things and I
regretfully decline the offer if that's the case and instead invite them to my
home.

~~~
eyegor
Most people own smartphones these days, which will also record and analyze
everything they can hear.

~~~
_-___________-_
> which will also record and analyze everything they can hear

Do you have a source for that blanket statement?

------
BiteCode_dev
Is it just me or the article has been taken down ?

~~~
ronyfadel
Just you

