This document describes how to setup an ethernet bridge. What is an ethernet bridge? An ethernet bridge is a device that controls data packets within a subnet in an attempt to cut down the amount of traffic. A bridge is usually placed between two separate groups of computers that talk within themselves, but not so much with the computers in the other group. A good example of this is to consider a cluster of Macintoshes and a cluster of unix machines. Both of these groups of machines tend to be quite chatty amongst themselves, and the traffic they produce on the network causes collisions for the other machines who are trying to speak to one another. A bridge would be placed between these groups of computers. The job of the bridge is then to examine the destination of the data packets one at a time and decide whether or not to pass the packets to the other side of the ethernet segment. The result is a faster, quieter network with less collisions.