Kimmo Huosionmaa When we are talking about intruders of data systems, we must know that those intruders might be people who have spent years in the system, before they begin to leak information. This kind of intruder is harmful and hard to remove because he or she had become a member of the team. And that's why those sleepers are very hard to locate and isolate. Many people noticed that is written with spy term, what is in John Lé Carre's novels. Those methods are used in everyday life of industrial spying and information stealers world. A methodology of this kind of operation is, that when spying organization will get one person to the certain position of the system, he or she can make very much harm to that system. An agent might use harassment as a weapon with fumigate other workers out of their job and replace them with people like him or herself. That's why in systems must use offensive security, where security workers work undercover that they see what reall...