TEMPEST protection

[Dale Thorn]

Cynthia H. Brown wrote:
> On Tue, 11 Mar 1997, Dale Thorn wrote:
> > Actually, the computer you type on will be very easy to pick out
> > of the noise field with modest spy equipment sitting down the street.

> Other places to look for emissions: the power supply, and the connection
> points for peripherals.  Make sure you leave adequate ventilation, though
> (another tricky part).

Funny thing was, first time I used PGP I was typing in a passphrase
and apparently PGP was doing something to the keyboard processor
on my laptop, because all of a sudden I thought I'd gotten bat's
ears - I could hear interesting new noises every time I pressed a
key, which I hadn't heard before (at least at an audible volume).

It occurred to me that typing in a PGP passphrase would be a
particularly bad time to increase the emissions....