I have a Cisco 857 router atached to an ADSL connection with a static IP address. The router is connected to an ISA server. I want the ISA server to have the External IP address, rather than a private IP which is NATed. I don't have much experience with Cisco, I've been landed with this thing and no budget to buy a simpler router, but I've been trying to set it up using SDM, unsucessfully.
How can I set up the router so that the network adapter on the server behaves as if it is directly connected to the web, with no firewall or NAT or anything?