Who's Spying?
 

I dated a lady for about 5 years and the company she work for, you had to have a sponsor and her company's sponsor was NSA
and she told me about stuff like this but I had no ideal that regular people could get it.

Another normal day, but outside across the street sits a parked windowless
van. Inside, an antenna is pointed out at you, they see everything you see
on your monitor. All those bank accounts, share plans...

Tempest & Tempest Attacks

If you are familiar with computer security, intelligence or electronic
surveillance then there?s no doubt that you have heard about TEMPEST.

TEMPEST Attacks work on the principle that electronic devices such as
monitors or fax machines emit electromagnetic radiation. With the correct
equipment like antennas and receivers a person may intercept these
emissions from a remote location (like across the street) and then replay the
information that was captured. Just think how this sort of thing can be misused.
It?s a big privacy invasion. Closing doors or blinds won?t do anything to stop a
TEMPEST attack. If your monitor was displaying sensitive material then it
would be exposed.

Properly shielding devices to stop emitting "information" is known as
TEMPEST.

The word TEMPEST relates to a set of standards used to reduce emissions.
Generally electro magnetic radiation. A simple example is when using a
vacuum cleaner next to your TV. Sometimes the picture goes fuzzy . This
fuzziness is caused by emissions from the vacuum cleaner interfering with the
TV. Then there is TEMPEST devices. They are simply devices used to monitor
the electromagnetic emissions. TEMPEST attacks are where TEMPEST
devices (and maybe extra equipment) is used to actually eavesdrop on
someone. A person can see your monitor from nearby without you knowing.

TEMPEST has been enclosed in a lot of secrecy. However most of this is
really isn't warranted. There is a lot of information on the Internet about
TEMPEST and TEMPEST attacks. All you have to do it search.

If you want to read the whole thing. http://www.surasoft.com/tuts/tempest/index.html