Abstract
Tempest and Echelon are the method of spying in a sophisticated manner; both are developed by National Security Agency (NSA) for monitoring the people. These technologies are originally developed for pure military espionage, but hackers use them now for spying into other people activities. Tempest is the technology which reproduces what you are seeing in your monitor, what you are typing in your keyboard from a couple of kilometres away. It traces all electromagnetic radiation from the victim’s monitor, keyboard, even PC memory and hard disk, and then it reproduces the signals. By using this technology it is possible to intrude only listening into a person’s computer from a couple of kilometres away, even it is a computer which is not networked and enables the intruder to hack without any connection to the victim’s computer. ECHELON is the spying on a large network by sniffing through the words. It is the ongoing secret project of NSA and its counterparts in UK, Canada, Australia and N