Kimmo Huosionmaa The cyber warfare and the importance of it are now understood in the western military. The best way to make lethal damage to the computer system is to use the logical bomb. In this case, the computer virus would be activated in the middle of the combat situation, what would decrease the ability to use the weapons. Another version of this operation is to change some codes inside the fire control system and delete the electronic codes of the master keys. And in this case, the computer would not recognize those keys. That means that the key would not activate the fire control computers, and that will be the very bad thing for the warship, what is under attack. The question about cyber security is vital for military forces around the world, and in the worst scenario some person would paralyze a multi-million dollar warship by using a mobile telephone, and in the real world, that kind of threats would cause problems even for the security of the nuclear weapons. The