Asynch designs

Roy J. Tellason rtellason at
Sat Aug 12 19:38:53 CDT 2006

On Saturday 12 August 2006 07:17 pm, Scott Quinn wrote:
> > Supposedly, non-clocked logic can also offer greater security because
> >there's no clock signal for remote sensors to key on when trying to
> >sense what the CPU is doing.   This seemed a little odd to me.  Do
> >espionage types really try to sense what a processor is doing
> >remotely, based on the EM emissions from the chip?
> Don't know about processors, but Tempest had a proof of concept for
> intercepting I/O from kbd/video. (Anyone else remember Tempest? for a while
> they were selling big "tinfoil hat" type shields for monitors and then,
> suddenly, it went away.) Was that NSA that came up with the POC?

Yeah,  I remember it.  Some of the service work I did back when was on a local 
Navy base.

Along with those boards I posted about,  there were some other weird bits,  
which I think I sitll have around someplace -- panels with some standard 
connectors but which were *seriously* shielded,  and grounded,  and with some 
interconnecting cables (the stuff they connected to wasn't with the junk) 
that were also shielded as well.  Rather odd stuff,  that.  I'm guessing it 
was part of some kind of a setup that was designed to counteract that way of 
gathering information...

Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space,  a critter that can
be killed but can't be tamed.  --Robert A. Heinlein, "The Puppet Masters"
Information is more dangerous than cannon to a society ruled by lies. --James 
M Dakin

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