Abstract: “\"SECURITY\"in this contemporary scenarios has become a more sensible issue either it may be in the ―REAL WORLD‖ or in the ―CYBER WORLD‖. In the real world as opposed to the cyber world an attack is often preceded by information gathering. Movie gangsters ―case the joint‖; soldiers ―scout the area‖. This is also true in the cyber world. Here the ―bad guys‖ are referred to as intruders, eavesdroppers, hackers, hijackers, etc. Today the illicit activities of the hackers are growing by leaps and bounds, viz. ., ―THE RECENT ATTACK ON THE DNS SERVERS HAS CAUSED A LOT OF HULLABALOO ALL OVER THE WORLD‖. However, fortunately, the antagonists reacted promptly and resurrected the Internet world from the brink of prostration. Since the inception of conglomerating Computers with Networks the consequence of which shrunk the communication world, hitherto, umpteen ilk of security breaches took their origin. Tersely quoting some security ditherers – Eavesdropping, Hacking, Hijacking, Mapping, Packet”

Keywords: Secrecy, Authentication, Non Repudiation and integrity control.