Comment Re:Remember TEMPEST? (Score 1) 264
Hi.
the Nyquist limit of the audio sampling hardware of a cell phone over instruction rate of a modern CPU is a pretty small fraction.
Hi.
the Nyquist limit of the audio sampling hardware of a cell phone over instruction rate of a modern CPU is a pretty small fraction.
The "audio" in question is most likely all below 24 kHz, that being the Nyquist limit for the 48 kHz sampling hardware, unless it happens that some phones can actually sample faster, and have microphones that can respond to higher frequencies.
The instruction rate of the CPUs in question is many times that frequency.
It doesn't sound likely.
Using multiple cores turns out to help the attack (by shifting down the signal frequencies).
Say what? Through what mechanism would multiple cores shift down the frequency? And what about parallel instruction streams contributing to noise?
TEMPEST was a details-secret government requirement meant to defeat means of eavesdropping on classified computer data from its electromagnetic emissions. I guess they need to include audio too.
My impression is that the noise comes from the power supply, not the CPU. I can certainly hear it with some computers, and it is related to work on the video card in my experience. I'm astonished that you can actually pull data from that, and in fact I'd like to see independent confirmation before I believe it.
My google search on the issue came up with Ghana, Burkina Faso, and Bangladesh. Two of which seem to be African, the latter South Asian I guess.
I'm sure you can come up with better data.
Besides infant mortality, there's probably unreported miscarriage.
When I was a kid I did Unicef collection every Haloween. We got an orange cardboard coin box at school, and collected donations to it along with our trick-or-treat. Unicef used these funds to build water wells for people in Africa who had only access to contaminated surface water.
A decade or two later, we found that many of these wells accessed aquifers that were contaminated by arsenic. And that thus we kids had funded the wholesale poisoning of people in Africa, and that a lot of them had arsenic-induced cancers that were killing them.
OK, we would not make that mistake again, and today we have access to better water testing. But it caused me to lose my faith that we really do know how to help poor people in the third world, no matter how well-intentioned we are.
And we had better not go around curing disease withoput also promoting birth control. Despite what the churches say, and the local dislikes and prejudices. Or we'll just be condemning more people to starve.
This might as well be how Blackberry, Nokia, and Palm blew it. And I'm probably leaving off a few companies.
IMO it all comes down to arrogance about your own platform. In Nokia's case that was Symbian.
Force needed to accelerate 2.2lbs of cookies = 1 Fig-newton to 1 meter per second