Firewalls are simply protective and defensive systems that stand between your local network (one computer or dozens) and the Internet. Correctly outfitted and updated, a firewall prohibits unauthorized access to your network by analyzing the data traffic that enters and exits, according to how you have configured it. It can ignore and/or alert you to suspicious, unknown or unsecured locations from which information is coming in, or even to which it is going. Essentially, it is a barrier to attacks from the outside, a barrier that takes very good notes about what is going on.



Firewalls can be hardware, software or, ideally, a combination of both. Along with limiting access to your network's computers, a firewall can also control remote connections to private networks by the use of authentication routines and activity logs. We should be far enough along the "information superhighway" for everyone to know that our computers and networks need this sort of protection, and few businesses today operate without it. If you need new or improved protection for your new or improved network, you can get it by doing just a bit of research, no matter what size your company is. This article is a good place to start if you are responsible for choosing the best firewall protection for your corporate needs.

Hardware solutions

Although hardware firewalls can be purchased as stand-alone products, more commonly they are found in the broadband routers that homes and small to medium-sized businesses (SMBs) typically set up. Either way, hardware firewalls can be very effective even without any special configuration, and can protect every computer on the local network "behind" it. Even the consumer (or "prosumer") broadband routers normally have two to four plug-in ports, whether they are wireless or not, but it is easy to find business-grade network firewalls for more connectivity.

By using "packet filtering," a hardware firewall examines packet "headers," which carry information about the source, contents and destination of that data. When compared with some predefined and/or user-defined rules, the firewall will decide to forward or deny ("drop") the packets in question. With today's equipment, a person with generalized computer technology know-how can set up a hardware router and/or firewall, make a few decisions, finalize a number of settings and have everything work just fine.

Who is doing the work?

Of course, ensuring maximum security and protection from a hardware firewall depends on learning its unique features, enabling and maintaining the settings, testing the setup and confirming that it is doing an adequate job. One of the main considerations for choosing the right firewall, therefore, is just who will be doing this setup and maintenance. If you are not tech-savvy, get someone who is, particularly for the initial setup. Firewalls can differ greatly, so you (or someone you designate) will need to review the manual and other documentation that will accompany the firewall you choose. The manufacturer's website and other Internet tech resources will typically provide instructions and "FAQ" pages, both generic and product-specific, to start you out.

Ongoing maintenance is usually not a problem, but if there is no one on site with the expertise, have a few phone numbers you can call if something goes haywire. You will be able to test your firewall with low- and even no-cost third-party software packages, and the Internet is home to more than a few online firewall test services. In fact, firewall testing will remain a vital part of your maintenance regimen, as you must always ensure you stay updated and configured for maximum safety.

Software solutions

For the average home user with a modern broadband router, some firewall capability is built-in. Still, software firewalls are popular and installed widely, in large part because every major microcomputer operating system (OS) has this functionality built in. You can easily customize the software firewall settings, whether they are part of the OS or a third-party application, giving you a good measure of control over functions and protective features. Software firewalls can protect you from external attempts at gaining access to your computer(s), and many software firewalls also guard against common "Trojan horse" programs and e-mail worms.

It is important to note that software firewalls only protect the computers on which they're installed, not the network itself, so every computer needs the package installed. Each user can then setup controls for sharing files, accessing printers and blocking unknown/unsafe applications from inserting themselves into your system. Many software firewalls also include privacy controls, settings for web access and filtering, and other security features.

How to choose

There are many hardware and software firewalls from which to choose, and you need to do your usual homework to see what best fits your situation. Read the user forums in addition to product reviews, as the real-life experiences of other SMBs and individual users will save you a lot of time and effort. When you encounter a situation like your own, pay close attention to what the companies or individuals did (and didn't do) when making their firewall choices. Don't forget to consider the "processing hit," that is, the amount and kind of OS resources a firewall will divert from other system operations, and double-check compatibility issues, too.

Although a hardware firewall is independent of your system, a software firewall runs in the "background" and should not consume more than a small amount of system resources. You will need to monitor all firewalls once they are installed, and for your software firewall you will need to download updates from the manufacturer. Software and hardware firewalls do different things to the same end, and to protect your computer and your network the most effective way you should certainly use both. If you do your research, consult some experts if necessary, get the right hardware, install your choice of software, get the product updates and maintain the firewalls on an ongoing basis, you should be in pretty good shape. Just remember that, if something happens that you do not understand or cannot fix, get proper assistance.