While the rest of America is busy wondering how on God’s green earth LaToya London got axed from American Idol, I’ve been trying to figure out how my firewall works.

It’s well named. We all know that in a building or car, a firewall keeps a fire from spreading. It essentially does the same thing on a PC. Simple to understand, until you find out that a firewall can be hardware or software. Still not a major problem — we’ve been using the word “server” like that for years. But my recent bout with viruses forced me to dig a bit deeper into this firewall issue. I knew this much: if your PC is unprotected, a hacker sends you a  malicious virus or worm, which you blissfully embrace before spending spend the next five days with a bottle of Maalox wondering how you can blame the whole mess on your ex-wife.

In the midst of my virus storm a few weeks ago (I contracted five inside of an hour), a neighbor advised me to buy a hardware router with firewall capabilities. On my way to Radio Shack, I decided to call in a second opinion from an old friend.

“Tom, I’ve got a new PC that I want to secure from nasty things like viruses, worms, and politicians. Do I need a firewall or just anti-virus software?”
“You should get both. By the way, how did you get my number?”
“Your son Zack gave it to me when I saw him at the mall last week.”
“Remind me to ground Zack for the rest of his life.”
“Oh, is this a bad time to call?”
“If I help you out, will you leave me alone?”
“Sure, old buddy.” (Tom is such a kidder, always pretending like I’m bothering him.)
“Ok, here it is. A hacker wants to find a weak spot into your PC, just like a burglar looks for an unlocked door to your house. If you have an ‘always-on’ Internet connection like a DSL line, the hackers are probing your system night and day. A firewall filters the information that comes into your PC. If the firewall doesn’t like the data, it doesn’t get through. So a firewall protects you from a bunch of things like hackers, spam, and anything else that wants to take over your system. That’s the kind of stuff you need a firewall for. Your house has good locks on the doors, right? So get a good firewall for your PC. And then you need to load anti-virus software on top of that, and keep it up to date.”
“I already know about the anti-virus software. I’m running Norton.”
“Norton’s good. Also McAfee and ZoneAlarm.”
“So why are there hardware and software firewalls?”
“How many computers are you running at home?”
“Just one.”
“Then don’t waste your money on a hardware firewall. It won’t make your system any more secure than a software firewall.”
“But if I’m running more than one computer, I should get a hardware firewall?”
“Right. If you’re on the Web with two or more computers, you want the outside world to think you only have one. A hardware firewall will make it look like there’s only one IP address at your house. Besides, if you’re running a couple of computers, you need a DSL router anyway. That’s why a lot of hardware firewalls are packaged with routers.”
“Ok. So I’m okay with the software firewall for now. But if Microsoft ever gives me that Tablet PC I’ve been asking for, I need to get a DSL router with a built-in firewall.”
“If Microsoft ever gives you that Tablet PC, I’m dumping all my stock.”

The Norton package I bought has both a firewall and anti-virus, along with anti-spam and a few others. It’s been running fine for a couple months now and I feel safe. Every once in awhile, it pops-up a screen that says “We’ve detected a possible intrusion, but we’ve taken care of it so rest easy.” Sometimes I wonder if that’s just a fake thing they built into the program to make me feel like I didn’t waste my money on the software. But I don’t think so. I can remember when Peter Norton himself used to appear on the cover of the software boxes. Grey hair, glasses, sleeves rolled up, arms crossed. He looked like the tech world’s John Wayne. You just got the idea that the guy could take care of business.

Yeah. My computer’s safe.