A firewall (one word) is a computer program (which could be implemented in software or hardware) which automatically prevents unauthorised access to a computer that's connected to a network.
To connect to a computer you can use so-called ports. These can be real (for example, a parallel printer socket) or numbered virtual ports. When you connect to the internet you are typically connecting through one or more virtual ports, each of which may be dedicated to one or more well-known functions. For example, browsers use port 80, and outgoing email usually uses port 25. A firewall prevents anything other than the specified functions from using the ports - this is called blocking the port. Normally firewalls give you several configurations of blocked and unblocked ports from which you can choose. Or you can set your own configuration. As others have mentioned, you can use the firewall supplied by the operating system, or use one built into your modem (if there is one built in). I use the firewall that's built into my wireless modem/router. Normally those built into a modem are considered to be better than those supplied by the operating system. I've never examined this claim, but just take it on trust. The benefit is that it protects your computer from unauthorised access (hacking). The cons are that it's a bit of extra cost, either as money or cpu cycles or both. You can get one from a computer store if you don't have one built into your modem. Check the documentation in your modem first, but if you're still using dial-up, chances are you don't have one. If you're using XP and are patched up-to-date you're probably using the Windows Firewall already. http://www.microsoft.com/windowsxp/using/security/learnmore/atkin_firewall.m spx -- Cheers, Bob > -----Original Message----- > From: Shel Belinkoff [mailto:[EMAIL PROTECTED] > Sent: 12 May 2006 16:36 > To: pentax-discuss@pdml.net > Subject: OT <LOL> - What's a Firewall? > > It's been suggested that I install a fire wall, but I don't > really know what one is or how they work. So, what's a fire > wall, how does it work, what are the pros and cons of using > one, and where can I get one? > > Shel > > > > > >
