What's a firewall, and how do I set one up?

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Where I work we all have the same lap tops and/or computers. All settings are to be the same. Some people can access a particular web site but I cannot. I have searched for something that is set differently than the others but I am frustrated. Please help.

ummm, Leo, stick to computers. The Dash Panel (not the metal and plastic construction you can see and touch and which is correctly named Instrument Panel in the automotive industry) or Floor Panel which are steel panels under your feet and between the interior of the car and the engine compartment, are NOT there primarily to "prevent fires from roasting the driver and passengers". Yes, it may have that benefit in certain rare circumstances but its sole purpose is as a structural component of the body and to mount 'things' on. And rest your feet :P. If you call that part of a car a firewall, it's poorly considered slang and quite misleading in its literal sense. Yes, I know people use the term but they're not using industry terminology.

The original firewall was a functional element of adjoining houses to prevent a fire in one from spreading to the other. In that context, a computer firewall is a perfect analogy.

Sorry to be picky but in a previous life I was an IP (Instrument Panel) engineering specialist in the auto industry - I couldn't let your example go unchecked.

Apart from that; great article.

While I understand a broadband router could be an effective hardware firewall for PCs, I am not clear if it is functionally any different between a modem connected to a router vs a single unit with both modem and router.

Should be roughly equivalent. Quick test: if the IP addresses on your local network are "192.x.x.x" addresses, you're probably good - you have NAT router, somewhere.

30-Sep-2009

Reading the article on Firewalls reminded me of a personal experience I would like to share with your readers. I Signed up for magicJack service for making free phone calls through your computer.[$40 first year, $20 yearly after.] For five weeks I could not make the thing work. Finally a company engineer shut off my Verizon Firewall and allowed only my Windows one. I began making my calls right away. The voice may fade a little sometimes but I am happy with it. Just watch out for two firewalls causing problems.

I'd agree with only a hardware firewall if only one computer is being protected and it is a desktop computer and not a laptop that goes on the road.

The hardware firewall only approach fails to detect other computer(s) intranet access on the same subnet, say a home based LAN. If one of the other computers takes in a virus, e.g., via a USB flash drive, it could be spread to the other computers via rouge network access.

Therefore, I recommend always using a software firewall except for as noted above.

Hi Leo,
AT&T came out yesterday to install internet service at my home. It's wireless and my desktop is working great. However, when I tried to access the internet from my laptop, it doesn't seem to work. Under "Network Connections", I right clicked on the "Wireless Network Connection" icon and when I click on "Enable" it says "Not connected, Firewalled" Is it possible to change the firewall settings so that I'm able to access the internet? I don't want to remove the firewall completely, for the reasons you stated in your article. Thanks!

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