Quote:
Originally Posted by Skybird
...
Can something like this also be done by identifying the presence of a smartphone due to the mobile phone cell it is currently situated in, even if its WLAN and mobile internet connections are turned off? One needs to remember all the time that a smartphone perate in three different radio circuits, minimum: phone, mobil internet, WLAN.
I once have red somewhere that the NSA even has methods to turn on a smartphone that was completely switched off, although this, as I remember it, needed a quite targetted an deliberate effort. At least for the time being.
And are RFID chips - in plastic cards - really blocked from getting passively read by a close-by detector if you put aluminium metal foil around it?
...
|
Even with the internet and WLAN functions turned off, yes, a cell phone can be located if it has GPS built in; even without GPS, pinging and triangulating off nearby towers can get someone a pretty close approximation of your position and/or location...
The NSA has long been reputed to have the ability to turn on turned off devices, but the NSA has been very coy about actually admitting the capability; given it is the NSA, the good bet would be "Yes". However, in order to legally do such an action, the NSA would need a warrant from a FISA court, which would mean a very limited access, both in scope and time and the NSA, or any other agency, would have to give the court very, very specific reasons and/or evidence to back up a warrant request...
I've read varied views on the efficacy of aluminum foil to block RFID; some (usually those wanting to sell their nigh-priced alternatives) claim foil does little to block RFID. The most consistent view I've seen is foil will block most RFID readers at long range, but at closer range, say, a couple of inches, the reader may detect an RFID device; what is interesting, in most of the tests I've seen, a majority of the more thorough tests have shown, while the RFID devices are detectable, the foil actually prevents the RFID device from transmitting back to the reader, essentially a one-way situation, sort of like a diode...
<O>