To view the demonstrations, you will need a Java (tm) enabled browser. The applet will need to download about 100 KB of data, but while running, it will take up 8 MB of RAM. Also, the animation of the traffic is CPU intensive. You can change the sleep delay between updates to smooth out the drawing of the animation.
Look under the file menu to do such things as change the scale of the drawing, change the sleep time between successive drawings of the network when playing back the animation, and quitting.
Note, the scrollbars do not work properly on some platforms. Specifically, dragging the thumb does not always work on PCs. However, it is still very useable, even with this problem. (In fact, this applet was developed on a PC.)