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Comment on RSA Key Extraction via Low-Bandwidth Acoustic Cryptanalysisparent

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I wonder whether this is specific to laptops (running from battery or otherwise not grounded) or if it also works with properly grounded desktop computers.

My HP notebook from ~2000 had measurable (although very high impedance) 110V AC between exposed metal parts and PE in wall outlet when connected to charger. Modern thinkpads (and probably all non-Apple laptops sold in Europe) does not seem to have this problem as ground is connected through in charger, not only AC coupled to both hot and neutral.

Macbooks can be grounded, too. The round metal thing that's holding the plug in place also serves as a connection for ground. It is moot if you're using the small plug which doesn't have ground but if you connect the cable instead of the plug, or use a UK plug, the computer is properly grounded.

I have been finally able to download and read their full paper and it seems to answer this question: they observe that grounding thru AC charger does increase SNR of measured signal.

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