Here is my current set up. I have a cable modem connected to my Airport Extreme Base station. I don't think I set any sort of security setting when I set it up I just plugged it in and ran with it. Wirelessly connected to the base station is my Powerbook and my G5 iMac. I also have an airport express hooked up in the living room to extend the range and stream music to my home theater system. Right now I'm probably wide open so what to do I need to do to make this network secure? Thanks in advance.