I think it's called auto port configuration in icamsource...something like that. However, NAT port mapping protocol does not sound the same as uPNP...it sounds like what you would use to manually forward specific ports to specific IP addresses within your network. I'm not a Mac guy, so I can't really help you with your router. I'm sure the SKJM guys can help you if the sticky on port forwarding doesn't provide enough information. In the long run, I think you'd be happier if you:
1) Assigned the computer running icamsource (and any IP cameras) a static IP address within your network
2) Set up manual port forwarding for at least 7 UDP ports per camera, starting with 12000 on the Internet side of your router. On the network side, you can use whatever ports you want.
3) I'm not sure if the manual port forwarding option is visible on Mac's version of icamsource (it isn't visible by default on Windows version), so you might have to research how to get that option visible so you can set it. Set it to the same port range that you selected for the network side of your manual port forwarding. Once you have it set, start and stop icamsource to ensure the settings are saved.
4) Reboot everything (computer, router, iPhone) after all changes are saved. From then on, assuming no hardware changes, your connection should be rock-solid.
