TEMPEST Attacks Informative - Electromagnetic Security
EVERYWHERE -- All your security software and/or hardware will not protect you from TEMPEST Attacks.
TEMPEST Attacks has been used by well-equipped opponents involves the remote detection of the electromagnetic signals from your computer. This expensive and somewhat labor-intensive attack is probably still cheaper than direct cryptanalytic attacks. An appropriately instrumented van can park near your office and remotely pick up all of your keystrokes and messages displayed on your computer video screen.
Here are some important historic events regarding TEMPEST Attacks.
1962 NSA's Project Tempest (defensive methods) begins; During Cuban missile crisis, NSA(aboard Oxford spy ship) attempts to circumvent unbroken Soviet cipher system by capturing radiation emitted from Soviet cipher machines located at Russian communications station in Cuba. Noise spikes are also attempted to be captured, revealing rotor settings on older cipher machines.
1972 Canada's first embassy collection operation (Stephanie) in Russia uses TEMPEST proof safe to hold intercept equipment.
1985 Iverson builds TEMPEST version of IBM PC for Operation TEMPEST; Grid Federal Systems makes only NSA-approved portable TEMPEST computer using a plasma display.
1991 First American broadcast of electromagnetic eavesdropping is shown on Geraldo Rivera's "Now! It can be told" show, performed by Winn Schwartau; Jim Carter, in coordination with Benjamin Franklin Savings and Loan, demonstrates successful attack on Diebold ATM machine using TEMPEST;
2001 In Kyllo v. US, U.S. Supreme Court rules against unwarranted infrared detection by law enforcement against private homes.
Just remember, effective emanation security begins with the physical environment. Unless you can shield the wiring (telephone lines, electrical wiring, network cables, etc.), all of the copper around your PC and in the walls isn't going to stop emanations from leaking to the outside world.