I have installed a pix 515 and would like to implement a second firewall as this is a high security site. I like smoothwall (gpl 0.99) a lot, (especially because it has snort built in) but I don't have an idea on how to implement it into the existing setup as I am already using nat on the outside interface on the pix firewall. Smoothwall runs address translation between it's own interfaces (ie from green to red). Can anyone please assist? I would ultimately like to place smoothwall between the internet router and the pix. Can anyone advise me on how to go about doing this?