Re: Air gap technologies

[Crispin Cowan <crispin () wirex com>]

Frederick M Avolio wrote:

> Crispin says that the skeptics viewpoint is that a disconnected cable is
> like a long connected cable. Aleph says that they ae just as good. I would
> say "functionally equivalent, but practically -- in implementation -- very
> different. I maintain a short connected cable is equivalent to a very long
> connected cable but both are different from a disconnected one. If we
> cannot agree that a cut cable and a non-cut cable are different then we
> cannot discuss anything further, can we? :-) I bet we agree if I hand you a
> wire with copper showing and I tell you to put it in your mouth because,
> trust me, the wire is very, very long.

The anaolgy does not work:

   * For power:  current only flows if the cable is connected simultanesouly at
     both ends.  The only power that flows in such a scenario is the power stored
     by the cable's (negligable) capacitance.
   * For data:  data can be injected, stored, and the retreived.  This is in fact
     what the Air Gap does.

So the "gap" analogy is not really appropriate.  Whale's data switch is more like
a data capacitor than an air gap.


> And maybe that is a way to look at it. Would you grab onto the
> copper?  Would you if you knew and could prove that the wire was not
> connected to anything? Would you if I told you that it was physically
> connected but practically disconnected because the software just wouldn't
> send electricity down that wire... honest.
>
> I'm thinking that Whale has to build these boxes very big so that you can
> see the gap (Mind The Gap!), but they'd really be too expensive... :-)

Or the dialectric gets too big :-)

Crispin

--
Crispin Cowan, Ph.D.
Chief Research Scientist, WireX Communications, Inc. http://wirex.com
Free Hardened Linux Distribution:                    http://immunix.org

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