What's a Firewall, and Why Do I Care?

There's often a lot of talk in security articles about the danger of "open ports." This subject seems to be the cause of more confusion and excessive paranoia than any other that I can think of. So, here's a breakdown:

Basically, network communication is analogous to trying to send letters to people in an apartment building. In order to communicate with someone in one of these buildings by letter in real life, you need to know the street address, the apartment number, and what language they speak. An IP Address is like the street address of an apartment complex, ports are like specific apartments in this building, and protocols are what language each resident speaks. If no one is living in a particular apartment, itís kept closed up until someone moves in. Computer Security Research - McAfee Avert Labs Blog

Linked by shanmuga Thursday, 26th April 2007 2:18AM