Using and choosing a Firewall

What Is a Firewall?
A firewall is a piece of hardware or software that places a barrier between your network and the Internet. It prevents outsiders from accessing your network and systems and delving into your confidential information or performing malicious acts. It can further protect your systems by restricting the surfing activities of those on your network so that you aren't exposed to harmful code that they may pick up when visiting non-trusted sites.
A firewall examines each packet of data sent to your computer or network and decides, based on pre-determined parameters, whether or not to let it through. It also blocks attempts by unknown programmes that may find their way onto your system from communicating with the Internet.

What Doesn't a Firewall Do?
Firewalls don't protect your systems against viruses. For this you need anti-virus software that scans your computer on a regular basis and your emails as they arrive. These days you can get anti-virus software that integrates with firewall software so that you can monitor malicious code and intrusion attempts from the same place.
You should also keep in mind that firewalls aren't 100% effective. A good firewall will protect you against 99% of attacks, but there is always the possibility of one slipping through. There are determined hackers out there!
You thus need to make sure that you take other precautions to protect your systems, such as keeping to a regular back up plan. Also remember that a firewall is only as good as its latest update, and it's well worth your while making sure it's  current.

What Types of Firewall Do You Get?

• Hardware Firewalls
Hardware firewalls are easy to use and install and are usually faster than their software counterparts and tend to be more reliable. One of the real benefits of a hardware firewall is that it will often come bundled with additional services. So your hardware firewall may act as a router as well as say a DHCP server that automatically assigns IP addresses to all the computers on your network. A hardware firewall may be more expensive, but you get more for your money.

• Software Firewalls
Software firewalls traditionally run on top of your operating system, however these days they are even being incorporated, like the Internet Connection Firewall in Microsoft Windows XP. Software firewalls tend to be more flexible and allow you more control than their hardware counterparts, not to mention that they're less expensive. You can install a software firewall either onto the computer that acts as your Internet connection router, or on each system on your network.

What to Look for when Buying a Software Firewall?

• Ease of use - A good software firewall should offer you an easy to use interface that lets you effortlessly navigate through your choices and guides you through the process of setting up your firewall.

• Automatic updates - Your firewall vendor should also make regular updates available to you at a reasonable price, and if they're automatic all the better. Most vendors will give you at least a year's worth of updates for free, after which you will need to pay for them. Some vendors will even offer you updates for free for the lifetime of your product. It's thus a good idea to shop around and see what's out there.