George Orwell wrote the classic "1984" in 1949. He depicted a world in which the government controlled it's citizens and a world devoid privcy. Many of bthe things Orwell wrote almost fifty years ago have come to pass.
Surveillance technology has progressed to the point that is possible to identify individuals walking city streets from sattelites in orbit telephone. Telephone, fax and e-mail telecommunications can routinely be monitored. Personal information files are kept on citizens from cradle to grave. There is nowhere to run..nowhere to hide.....
The advent of the personal computer has revolutionized the way we do business, keep records, communicate and entertain ourselves. Computers have taken the place of typewriters, telephones, fax and telex machines.
The Internet has opened up a new world of high speed and inexpensive communications. How secure and private is it? There are many encryption programs and hardware devices available for security purposes but what about the computer terminal itself? How safe is it? What are it's vulnerabilities? Hackers have been known to cause mischief from time to time...Is it possible for an adversary to snoop on your private data? Can Big Brother?
Suppose it was possible to aim a device or an antenna at your apartment or home from across the street or down the block. Suppose you were working on a confidential business on your PC. Suppose that device down the block sould read what your were typing and viewing the CRT? Feeling uncomfortable? Suppose that device could monitor everything you do on your computer by collecting electromagnetic radioation emitted from your PC's CPU, CRT and/or peripheral equipment, reconstruct those emissions into coherent receivable signals and store them for later review? Feeling paint? Good... The technology exists.....and it has for some time.......
You don't have to worry about a “middle of the night” break-in by some clandestine government black-bag team to plant a bug. They never have to enter your home of office. Seedy looking private investigators or the information warrior won't be found tampering with your telephone lines in the basement either...it's not necessary...all they have to do is point an antenna...safely from a distance away...and collect your private data...
This surveillance technique has become known as TEMPEST monitoring. TEMPEST stands for Transient Electromagnetic Pulse Standard. It is the standard by which the government measures electromagnetic computer emissions and details what is safe (allowed to leak) from monitoring. The standards are detailed in NACSIM 5100A, a document which has been classified by the national Security Agency. Devices which confirm to this standard are called TEMPEST certified.