Trilight Zone

[thedark]

A firewall is a structure intended to keep a fire from spreading. Building have firewalls made of brick walls completely dividing sections of the building. In a car a firewall is the metal wall separating the engine and passenger compartments.

Internet firewalls are intended to keep the flames of Internet hell out of your private LAN. Or, to keep the members of your LAN pure and chaste by denying them access the all the evil Internet temptations.

The first computer firewall was a non-routing Unix host with connections to two different networks. One network card connected to the Internet and the other to the private LAN. To reach the Internet from the private network, you had to logon to the firewall (Unix) server. You then used the resources of the system to access the Internet. For example, you could use X-windows to run Netscape's browser on the firewall system and have the display on your work station. With the browser running on the firewall it has access to both networks.