Initially we started by having the software installed on a client computer inside the firewall and using the router to point to it via a single IP and Port, as Bruce suggests. Then, because we were a bit concerned about security, we started selling our system on Netbooks, preloaded, but installed inside the firewall, but not connected to the network (shared) in any other way, other than the router connection. So it sounds like we should still be okay. We've always used the web directory as sort of the DMZ for the apps.