In recent times, the worldwide network connection is beginning to play a more important role in our lives. Since the modern societies are full of growing number of cyber crimes, network security seems to be a necessity in normal life. .
There are various definitions of "network security". The American National Standard defines Network security as a "Protection of networks and their services from unauthorized modification, destruction, or disclosure." The standard also mentions that the network security "provides assurance the network performs its critical functions correctly and there are no harmful side-effects". (1).
Network is a fairly recent concept. But it grows so fast that most people now are using either WANs (Worldwide Area Networks) or LANs (Local Area Networks) to exchange information, build up communications, or running business. As the uses of networks expand, so do the various kinds of "cyber-crimes" come out in the society as well. The adequate security systems for computers and networks are needed. If not, there will be a higher probability of the computer system being attacked. All the network users will be affected by the breaches in network security system. To this point, network security technologies are vital in preventing network users from intrusion. .
Not only the techniques for threats to network are developing, but also the techniques for protections are developing. The Problems that are caused by hackers or other intent people can be protected. Here are some common protection methods.
In this rapidly developing, high network dependent world, security for the systems seems to be increasingly important.
The modern world is full of something like virus, Trojan Horse Programs, and variety of attacks. Threats to the system are not only caused outside of the system, which can be easily protected by using firewalls or other antivirus software packages, but also inside the system.
