What is Security?
Network security is essential because the Internet is a network of interconnected networks without a boundary. Because of this fact, the organizational network becomes accessible and vulnerable from any computer in the world. As companies become Internet businesses, new threats arise from persons who no longer require physical access to a company's computer assets.
In a recent survey conducted by the Computer Security Institute (CSI), 70 percent of the polled organizations stated that their network security defenses have been breached and that 60 percent of the incidents came from within the organizations.