I have an extra desktop PC with 2 NICs that I'd like to use as my home firewall. I'll install a linux distro meant to be used as a firewall on the desktop.
I was thinking of placing it in between the cable modem and wireless:
modem <-> desktop_NIC1 <-> (firewall software) <-> desktop_NIC2 <-> wireless router <-> laptops, ipads, etc.
I figure it has to be here in order to filter traffic for my entire network, right? I see a downside in that the firewall won't know what machine to associate traffic with, since it's outside the router's network.
Is this correct? If not, how would you suggest doing it?