Re: cellphones as room bugs

2006-12-03 Thread John Ioannidis
On Sat, Dec 02, 2006 at 10:21:57AM -0500, Perry E. Metzger wrote:
 
 Quoting:
 
The FBI appears to have begun using a novel form of electronic
surveillance in criminal investigations: remotely activating a
mobile phone's microphone and using it to eavesdrop on nearby
conversations.

Not very novel; ISDN phones, all sorts of digital-PBX phones, and now
VoIP phones, have this feature (in the sense that, since there is no
physical on-hook switch (except for the phones in Sandia and other
such places), it's the PBX that controls whether the mike goes on or
not).

I've always wondered what legitimate use the ability to turn on the
microphone of a *mobile* phone remotely was.  No mobile telephony
company has ever advertised this as a feature.

/ji

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Re: cellphones as room bugs

2006-12-03 Thread Steve Schear

At 07:21 AM 12/2/2006, Perry E. Metzger wrote:


Quoting:

   The FBI appears to have begun using a novel form of electronic
   surveillance in criminal investigations: remotely activating a
   mobile phone's microphone and using it to eavesdrop on nearby
   conversations.

   The technique is called a roving bug, and was approved by top
   U.S. Department of Justice officials for use against members of a
   New York organized crime family who were wary of conventional
   surveillance techniques such as tailing a suspect or wiretapping
   him.


This technique was pioneered by some criminals (drug, I think) that would 
'forget' their cell phones in police cars to they could listen in on them.


Steve 


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Re: cellphones as room bugs

2006-12-03 Thread Steve Schear

At 07:21 AM 12/2/2006, Perry E. Metzger wrote:


Quoting:

   The FBI appears to have begun using a novel form of electronic
   surveillance in criminal investigations: remotely activating a
   mobile phone's microphone and using it to eavesdrop on nearby
   conversations.


BTW, its easy to thwart this, even without removing the battery as 
recommended: just place a shorted jack into the phone's mic/headset 
plug.  These plug's use an physical-electrical contact switching method to 
shunt the audio so the software AFAIK can route around it.


Steve 


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Re: Can you keep a secret? This encrypted drive can...

2006-12-03 Thread David Johnston

Jon Callas wrote:



Moreover, AES-256 is 20-ish percent slower than AES-128. 
Compared to AES-128, AES-256 is 140% of the rounds to encrypt 200% as 
much data. So when implemented in hardware, AES-256 is substantially faster.


AES-256 - 18.26 bits per round
AES-128 - 12.8 bits per round

I imagine that this would matter when the implementation is in a hard 
disk or disk interface.






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Re: cellphones as room bugs

2006-12-03 Thread Thor Lancelot Simon
On Sat, Dec 02, 2006 at 05:15:02PM -0500, John Ioannidis wrote:
 On Sat, Dec 02, 2006 at 10:21:57AM -0500, Perry E. Metzger wrote:
  
  Quoting:
  
 The FBI appears to have begun using a novel form of electronic
 surveillance in criminal investigations: remotely activating a
 mobile phone's microphone and using it to eavesdrop on nearby
 conversations.
 
 Not very novel; ISDN phones, all sorts of digital-PBX phones, and now
 VoIP phones, have this feature (in the sense that, since there is no
 physical on-hook switch (except for the phones in Sandia and other
 such places), it's the PBX that controls whether the mike goes on or
 not).

It's been a while since I built ISDN equipment but I do not think this
is correct: can you show me how, exactly, one uses Q.931 to instruct the
other endpoint to go off-hook?

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