A firewall works as a security doorway that stops unknown and seemingly harmful and therefore unauthorized entry to your personal computer network system. It acts as the first line of defense against programs that may harm your personal information. A good firewall protects your information from trojans, spyware, adware, hackers, malware and worms.

Firewalls are security-ensuring schemes that manage and decide who can gain access and send information to your computer network. Firewalls help both hardware and software. To ensure tighter security, most systems use a combination of each.

All messages to and from your computer pass first through the firewall. The firewall checks each and every message and bars those that are against the security criteria or rules laid down by your computer.

Simply put, a firewall acts as a security guard for your computer network. Anything going in or out of it is thoroughly checked by this security scanner and who it decides to keep away is completely based on the rules you have laid down!

However, firewalls are not as simple as they sound. They can be very complex. Firewalls can mean a whole aggregation of methods that can be used one by one or in combination, depending on the degree of security you need to attain.

Firewall methods may be of varying nature:

• Application gateway – this installs security methods on particular applications (FTP, Telnet, etc.)

• Packet filters – studies each operation running on your computer minutely and allows or discards according to rules set by your computer

• Circuit-level gateway – provides safety-ensuring techniques for connections like Transmission Control Protocol or TCP and User Datagram Protocol or UDP

• Proxy server - any message entering or exiting your network must pass this proxy server because it effectively conceals your computer address

Superior security is also provided by encrypted data. Many network systems use this method to strengthen safety measures.

To protect data that passes your computer network, installation of firewalls is a must. Plus, if you are a regular web surfer, the presence of a firewall becomes mandatory.

However, it is a known fact that no system is flawless. A computer or network plugged to the Internet is not far away from hackers! Therefore, it is wise to keep a back-up of important data on a secure off-line base: floppy disks, CDs, or on a computer that does not make use of the Internet. Daily or weekly back-ups ensure the safety of your data and programs.

A sound firewall provides adequate protection against illegal access to your computer by scumware like spyware and adware. A firewall provides an effective line of defense.