What is a DMZ, when/why is it used?

[jaffa]

Just wonder what the practial implication of a dmz is (I know what the abbreviation stands for), when/why one should use it.

Is it difficulat to set up and what does one need to be able to do it?

 

[JackMDS]

DMZ , or the "Shut Gun" approach. Each Cable/DSL Router allows you to put one computer on the DMZ (De Militarized Zone), i.e. no military no one is protecting you. Under this setting one of your Network computers is out in front of the Firewall, thus all the ports are Opened. Be careful while being on the DMZ the computer and its content is exposed to the Internet

You might want to read the whole page, http://www.ezlan.net/routers1.html

:sun:

 

[Brazen]

on a corporate firewall, the DMZ is a separate port that you can apply separate firewall rules to. Typically a company will not allow any incoming traffic to their LAN and put things like webservers in the DMZ, which could have all traffic but http blocked to it from the WAN, LAN or both

 

[Nothinman]

As Jack said, on most consumer devices a DMZ is simply shorthand for forward all ports to this specific host. It's like putting your computer directly on the Internet, almost.

In most corporate products a DMZ is used to seperate two parts of a network. Traffic from your backbone will be denied by default with only a few known necessary ports open for communication and usually only in one direction. For instance, if a unix box is in the DMZ you would most likely enable ssh from the backbone to the DMZ, but not vice versa.