How the Greek cellphone network was tapped.

[Charles Jackson]

An earlier post, talking about vulnerabilities and the lack of an
appropriate market response, said:
____________
We're talking about phone calls -- did all of the well-publicized
cellular eavesdropping (Prince Charles, Newt Gingrich (then a major US
politician), and more) prompt a change?  Well, there are now US laws
against that sort of phone eavesdropping gear -- a big help....
____________

I think the most publicized cases of cellular interception, including the
two mentioned above, were interceptions of analog calls.  Such interception
was not too hard to do.  In some cases you could pick up one side of such
calls on old American TV sets (sets that tuned above channel 69 on the UHF
dial).  Much better interception equipment was still pretty simple.  I
understand that there was sometimes enough talker echo that, if you listened
on the base-to-mobile link you could understand both sides of the call-you
didn't even need two receivers.

However, interception of digital wireless signals requires more skill and
expense.  Interception of CDMA is harder than interception of GSM.
Interception and recovery of encrypted digital is still more difficult.  The
3G wireless standards permit AES quality encryption of the voice-I don't
know if carriers have this turned on.  I am pretty sure they have it or the
equivalent turned on for functions that limit theft of service such as the
initial activation of service on CDMA networks.  

I do know of business executives who, when informed of the ease of
interception of analog cellular, changed their behavior.  

Chuck Jackson



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