Firewalls

A firewall is software that protects your system when it's connected to the Internet. It is named after the firewall used by fire fighters that acts as a barrier to a spreading fire. Computer firewall software analyzes all the data that enters and leaves your computer. A firewall operates according to the rules set up in its configuration. It works as an invisible barrier that protects your computer from different types of attacks over the Internet.

Advantages of a firewall:

• Protects your system by managing all incoming and outgoing data flows
• If correctly configured it is capable of protecting your computer from practically any attack
• It can prevent a leaking of personal information while you're working on the Internet (see Referrer, Ad Ware, Spy Ware)

Disadvantages of using a firewall:

• Inexperienced users might find some firewalls hard to setup and work with. Therefore such users may need a specialist's advice.
• Some firewalls can conflict with Internet applications, such as ICQ or chat clients, causing disruptions of their operations
• Firewalls are unable to locate and cure files infected with a virus or Trojan
• Software of this type is generally expensive

The main problem with most firewalls is they are not effective unless precisely configured. Fortunately many firewall manufacturers are beginning to make their software's interface simpler to use. Most firewall programs now use "rule wizards" to configure the software for the average person who has no special knowledge in the field of security.