I have been trying to figure out the network layout of a PIX behind a router. In particular, I want to understand the public/private addresses to be used on the different interfaces, the routing scheme, and where NAT would occur. It would be a simple layout of a LAN that is presently using a Cisco router (1700 series) to connect to a DSL line for internet service. Would the firewall be place in between the LAN and the router? would I have to create a unique LAN between the router and the firewall (using a scheme different from the LAN)? Or would the pix just be given 2 private addresses that are a part of the LAN, and directly connected to the private interface of the router? Thanks in advance.