Can the NSA Really Track You Through Power Lines? 109
mask.of.sanity writes Forensics and industry experts have cast doubt on an alleged National Security Agency capability to locate whistle blowers appearing in televised interviews based on how the captured background hum of electrical devices affects energy grids. Divining information from electrified wires is a known technique: Network Frequency Analysis (ENF) is used to prove video and audio streams have not been tampered with, but experts weren't sure if the technology could be used to locate individuals.
Not likely in modern communications (Score:5, Informative)
Due to the amount of signal processing that goes on with modern television, its highly unlikely. MPEG compression probably stops it at the source since its instantly fuddled with and massive amounts of the data they use is lost right then and there.
If you were actually afraid of the NSA finding you, as a whistle blower, getting around this form of tracing is trivial.
Use a UPS for power, unplugged from the power grid. No power line tracking.
Or the more old school way that people have done for a while, record it and leave before broadcasting it. Locating the source of the recording doesn't mean much if the target is already 800 miles away.
Well, sort of. (Score:2, Informative)
Tracking someone through landlines has been a Thing for many years now. Ever hear of a "lock and trace"? You can SORT OF do the same thing for power, by embedding a signal in a given substation. It's nontrivial, and it's horribly complicated, but it IS feasable. As for the "hum" thing, that's just standard TEMPEST, been a Thing now for going on thirty years, where you can fingerprint electronics via EM signatures and you can read those EM signatures via physical phenomena including audio hums and induced currents in surrounding circuits. This is why the LASER mike was actually developed, not for actual sounds (standard shotgun mikes do wonders there, because the glass reresonates sound just fine), but to get a good frequency signature on TEMPEST EM leakage. So, in sum, they're not specifically taking a van out and following lines to see what location an interviewee is at, but a lot of that is that they don't really need to because they can get all the information they need through older technologies that approximate the capabilities
Re:Interessting in any case (Score:4, Informative)
A city gets basic energy saving with a lot of optional extras to contain any freedom of assembly and association.
Voice as in mic, voice stress, gait, wifi and everything a camera offers over every road or public area.
Fun with wifi funds? 'SPD will shut off its new Wi-Fi after privacy backlash" (November 15, 2013)
http://seattletimes.com/html/l... [seattletimes.com]
CIA Chief: We’ll Spy on You Through Your Dishwasher (03.15.12) for the next generation of basic consumer appliances.
http://www.wired.com/2012/03/p... [wired.com]
Add in a smart meter https://en.wikipedia.org/wiki/... [wikipedia.org] with a rapid communications setting.
Then you have your tame game console with "webcam" from bands who love to help all govs over all product lines.
As for Network Frequency Analysis, it sounds like something others have hinted at from the TEMPEST generations. https://en.wikipedia.org/wiki/... [wikipedia.org]