Re: Quantum cryptography tackles video

On a sunny day (12 May 2005 13:36:06 -0700) it happened "Schoenfeld"
<schoenfeld1@xxxxxxxxx> wrote in
<1115930166.652817.182420@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>:

>
>Baugh wrote:
>> Schoenfeld wrote:
>> > But this protocol allows advesaries to simply packet sniff the
>quantum
>> > line for the intent of preventing communications between the two
>> > parties.
>> >
>> > Whats worse, private communications exposed to advesaries or
>advesaries
>> > preventing private communications completely?
>> >
>>
>> But that hasn't changed anything, you can simply cut the line instead
>of
>> tapping it. Point is that you can't tap the line without cutting it.
>
>One should not forget the wave property of light. It should be easier
>to jam a quantum line than a classical line.
>From a technical point of view, I think not.
I have designed some systems that used coax to transfer multiplexed data.
These were tested (for acceptance) by putting something like 1kV pulses on
the outside, then looking if the signal got screwed up, or any hardware damaged.
You will not believe how much signal gets through, 40dB demping is only 100x,
that still leaves 1000 / 100 = 10 V!
On an optical line, I am not so sure how you will even get to the fiber in
question without physically cutting the cable open, and then inserting
extra photons via the outside?
Glassfiber is really not that sensitive, but I have not tried that one.
.