Prime purpose of this article is to explain necessary outline of Digital Network Security. The significance of digital network security should not be minimized whether it is for a government institute or a large or small business. Intruders or hackers can generate huge amounts of spoil if they manage to get past the security shield. These concerns need that all users of a network be aware and practice essential security measures. Digital network security system analysts are skilled to manage both active and passive attacks. Active attacks disrupt a organism and may include: Reply, Service Denial, Masquerade and Modification.