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“Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

arstechnica.com

101–110 of 127 posts

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#101

Just because ultrasonics are inaudible doesn't necessarily mean they're harmless. Energy deposited into those little hairs in your cochlea is still energy. What does the research say about the impact of ultrasonics on hearing? I wouldn't be surprised if they're the same as any kind of sound, decibel per decibel. (They're easier to block out, being at a higher frequency.)

If you don't hear it, doesn't that mean the cilia aren't activated?

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#102
post #67

Earlier quoted context omitted.

Whoa, wait a sec there with your example. How would a reasonable person not want to be an organ donor??

Religious reasons, family not wanting that to happen, etc.

Here's some research: https://www.ncbi.nlm.nih.gov/pubmed/18555116

In short, only a few religions have anything to say against being a donor at death, and a few have something against being a recipient from a dead person.

If you think your religion might affect your decision to be a donor, check with a trusted authority figure and make sure.

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#103
post #87

Earlier quoted context omitted.

There is a theory that organ donors get worse medical attention and have higher mortality rates in hospitals. From what I've seen it doesn't hold up well against the evidence, but it's still within the bounds of what I'd call "reasonable disagreement".

That doesn't sound reasonable at all. That theory hinges on the idea that doctors would prioritize getting organs over actually saving people's lives, which would be a truly horrific violation of the hippocratic oath.

I see it just as an acknowledgement that I might not want there to be any possible cross-purposes of incentives in my own health.

Doctor's don't need to consciously change their behavior for there to be a difference in care. It's just that incentives are like really awesomely powerful things.

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#104

> all the time, even while they’re running in the background This is FUD. iOS does not give an app this ability without it being obvious (a banner across the top of the screen).

Apparently 9 in 10 smartphones today are Android and that lets you do whatever you want in the background.

Still FUD to say its possible on iOS (which they did).

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#105
post #49

I'm working on an app that passively picks up ultrasonic tones generated by SilverPush and sends out garbled data. The biggest issue with blanket interference across the entire ultrasonic band is that there are some legitimate uses that don't involve cross-device tracking. That's why we need to address this issue by selectively interfering with only known tracking schemes.

Can you elaborate on which legitimate uses you had in mind?

These are two services I know of that use it for cool stuff with user permission:

* Authentication: http://www.copsonic.com/

* Shopping deals: http://www.shopkick.com/

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#106

Earlier quoted context omitted.

Whoa, wait a sec there with your example. How would a reasonable person not want to be an organ donor??

There is a theory that organ donors get worse medical attention and have higher mortality rates in hospitals. From what I've seen it doesn't hold up well against the evidence, but it's still within the bounds of what I'd call "reasonable disagreement".

We're generally unaware of someone's donor status. I agree that unconscious bias would be a concern (directionality unclear) if that were not true.

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#107
post #49

I'm working on an app that passively picks up ultrasonic tones generated by SilverPush and sends out garbled data. The biggest issue with blanket interference across the entire ultrasonic band is that there are some legitimate uses that don't involve cross-device tracking. That's why we need to address this issue by selectively interfering with only known tracking schemes.

Do you have details on the encoding? I'm a bit suspicious of it being actually ultrasonic (device microphones often filter at 20khz or below) - seems more likely it would be audible spectrum noise with a ton of FEC.

They map each letter (A-Z) to a single frequency. The range is around 18-19.5 kHz. As far as I know, this range is inaudible to most adults. I couldn't hear it for example. Of course, I may be using the term ultrasonic incorrectly.

Some preliminary work was done last year to reverse SilverPush[1], but my group and I are planning to take it further.

[1]: https://github.com/MAVProxyUser/SilverPushUnmasked

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#108
post #49

I'm working on an app that passively picks up ultrasonic tones generated by SilverPush and sends out garbled data. The biggest issue with blanket interference across the entire ultrasonic band is that there are some legitimate uses that don't involve cross-device tracking. That's why we need to address this issue by selectively interfering with only known tracking schemes.

Where can we follow this project?

It's currently a course project we're working on. I will post it to HN once it's in a "good enough" state.

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#109
post #67

Earlier quoted context omitted.

Religious reasons, family not wanting that to happen, etc.

Here's some research: https://www.ncbi.nlm.nih.gov/pubmed/18555116 In short, only a few religions have anything to say against being a donor at death, and a few have something against being a recipient from a dead person. If you think your religion might affect your decision to be a donor, check with a trusted authority figure and make sure.

For sure, FWIW I'm personally an organ donor and broadly agree with your logic. Those are just some times when I feel the choice not to donate organs is valid.

A person's choice is probably always valid regardless of what it is, it's their body at the end of the day. In the normative sense I think everyone should donate their organs, but I'm not sure it can be reasonably codified.

Re: “Ultrasonic cross-device tracking” embeds inaudible tones in advertisements

#110
post #91
post #53

Earlier quoted context omitted.

Poor me, I can hear the ultrasonics generated to repel dogs and cats...

Yeah, apparently you're supposed to lose that ability in your mid-20's, but I still hear them loud and clear at 28...

I used to hear ultrasounds fairly well. It goes away unfortunately.
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