I have Sygate Home Network 4.0 and share a cable modem. I use the Zone and Game Spy all the time. Sygate allows you to determine what ports to use and what ports not to use, so you can program the ports individual games use. Its really simple once you install and read the instructions..never had a breach always catches the incoming packets and lets you know when a program is trying to access the web, good for trojan detection. Also lets you do a trace of the incoming intrusion, letting you know the originating ip address and sys ad for the service of the incoming packet. Cant go wrong with it. Its not as expensive as the other big name brands and a little less demanding then Zone Alarm. My firewall before using Sygate was Zone Alarm... They have a trial version.