Computer Basics

A firewall is simply a device, either hardware or software, connected between your private network and the public Internet.  It's job is to permit, deny or proxy data connections between you and the outside world.  The firewall acts like a guard at a gate that controls traffic between trusted and non-trusted zones.

Firewalls come in all kind of shapes and sizes and are designed for different network connectivity needs.  Installing a firewall does not negate the need for installing antivirus, antispyware or antispam software on your PC.  In it's simplest form it is simply another component for protecting your PC system and your personal information.  Having a firewall is essential when you have a direct connection to the Internet.

Why is a firewall essential?  The typical PC connected directly to the Internet with no protection will last about 10 minutes before it is compromised.  Except for the most highly motivated and persistent criminals properly installed and configured firewalls can eliminate the typical online threats that are common on the Internet.  Newer firewalls are available to serve roles beyond stopping the hordes at the gate.  Network address translation, anti-virus, proxy services, email scanning, intrusion prevention services, control access to offensive sites and many other services.  As stated above, having these services in the firewall does not remove the need for having active and up-to-date antivirus software on your PC.
Depending on the options you select and your needs firewalls can cost from less than $100 to several tens of thousands of dollars.  What's as important as the cost, though, is the configuration.  A firewall configured incorrectly is almost worse than no firewall at all.  If you plan to install your own firewall in your home network please take the time to ensure it's configured correctly.  All of the major firewall device manufacturers provide documentation to facilitate a good installation.  Firewalls are not difficult to configure, it just takes attention to detail.

Software firewalls, also known as personal firewalls, are also available.  In fact if you run Windows XP or Linux your system comes with a built in firewall.  Please read your operating systems documentation for more information about the installed software firewall.  Some antivirus software makers are also providing complete suites of security software with firewall functionality built in.  Symantec, TrendMicro and Grisoft are ones to look at.  Probably the most famous of the personal firewalls is ZoneLab.  The most important thing to remember about software firewalls is that they are designed to only protect the PC  they are installed on.  They will not provide firewall services for other PCs in your home or small office network.

Utilizing a firewall in your home or small office network will help facilitate safe communication between your local PCs and help to keep your network secure.  For a small investment a firewall you can protect your personal or company data.