<sorry for the earlier finger glitch> 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.
There's a company (I lost the brochure) who sell EM attenuator material, some preconfigured, and presumably some bulk. It should be easy to find on the Web. Once you get some really dramatic attenuation, particularly of the keyboard (and particularly during password confirmations, etc.), you should do your own preliminary monitoring with some of those band-sweep gadgets. Steady noise of course is nothing compared to the spikes from some of the keyboard outputs...
Once you've identified all (we can hope, can't we) of the problem signals still leaking through the shielding (albeit at greatly reduced levels), you can direct different kinds of efforts there, including random noise from other computers which use the exact same output devices.
From what I've seen, it's a lot easier for "the bad guys" to concentrate on monitor emissions - you can read the screen someone's looking at, and not just the key-clicks. Won't get you blanked-out passwords, though. Much of the monitor's emissions may be out the back.
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). Cynthia =============================================================== Cynthia H. Brown, P.Eng. E-mail: cynthb@iosphere.net | PGP Key: See Home Page Home Page: http://www.iosphere.net/~cynthb/ Junk mail will be ignored in the order in which it is received. Klein bottle for rent; enquire within.