How the Greek cellphone network was tapped.

[bear]

On Thu, 19 Jul 2007, Charles Jackson wrote:

>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....

Halfway, I think.  ISTR there are laws against manufacture for sale,
sale, purchase, or most usage of such gear - but no laws against
manufacture without intent to sell, posession, or some exempted
types of use of such gear.

Basically, owning such devices is not a crime, nor is using them
provided the "target" has been duly notified that their call will be
or is being intercepted.  So you can build the gear, and you can demo
the gear you've built on a call made for purposes of demo-ing the
gear.

Consult a lawyer first, but I believe it may also be legal to monitor
calls made in a given location provided you first put up a sign that
says "all cell calls made on these premises will be monitored" etc.
But you can't legally buy or sell the equipment to do it.

> 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).

The technical requirement was for a TV with a UHF analog *tuner* as
opposed to a digital channel-selection dial.  The channels that the
cellular network used (still uses?  I don't know) were inbetween the
channels that were assigned whole numbers in TV tuning.  So you could
pick up some cell traffic if you tuned, for example, to UHF TV
"channel" 78.44.  But not if you tuned to channel 78 or channel 79.

				Bear

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