Network security is one of the most talked-about subjects on the internet- but what is it and why is it important? Network security guards the computers in a network, business, school, or even home, against malicious software and viruses. An unprotected or under protected network will often run slowly and have errors, and occasionally will be knocked out entirely by hackers or malware. Fortunately, there exist solutions to vulnerable networks. Anti-virus software and vigilance on the part of administrators can protect a network and keep it functioning.

Network security operates on a fairly simple principle. Effectively, it identifies a user through an authentication process that usually involves a username and password. It is this authentication system that often leads to problems. The weakness of a network is generally not in the programming of the system itself but rather in the passwords of the users of the network. This is why good passwords are important. A single bad password can result in easy infiltration by hackers, who have sophisticated password-breaking programs.

Assuming a hacker gets past the password layer, he still has to break through the firewall. The firewall, simply put, detects anything that should not be entering the network and blocks it. Unfortunately for many businesses, employees often bypass the firewall using a proxy (a server that allows unreadable data transmission that cannot be checked for off-task workers– or viruses) in order to use sites blocked by the company. Malicious software quite frequently passes the second, stronger layer of defense in this way.

If a hacker gets past the second line of defense (the firewall), the final level of the networks “immune system” kicks in: the anti-virus. Network anti-viruses are necessarily more powerful than those of individual computers, and the cost of failure could be every computer on the network. A single infected computer could leave the entire network vulnerable. For this reason, an anti-virus needs to be fast and effective in quarantining infected files, or, in a worst-case scenario, the infected computer. Very few attacks succeed against a good anti-virus, and the news only gets better from there. Anti-virus programs are quite cheap (to protect a network can cost as little as $100 a year) and very effective.

Despite all these defenses, administrator vigilance is necessary to maintain all three levels of defense. An administrator can detect insecure passwords or even require frequent password changes. Moreover, administrators must block proxy sites to keep malicious software from breaching the firewall. Finally, the network operator must maintain the anti-virus and keep it current by downloading the latest virus definitions regularly. If all these steps are followed, a network is likely to be very secure.