I've not yest seen a modem or router where the firewall is different than the port forwarding. Going back to portforward.com, their first line is all ports, too, and it shows 0.0.0.0. I don't know what it means. This is one goofy modem. Doing more research on this modem shows that some people have had luck by disabling the modem's built-in firewall. If this were the modem my phone company gave me, I think I'd go to the store and get another one. But I'm not entirely convinced that other software is not to blame.