I recommend also settings up a static IP address, as it may change. You can find other connection advice here: Activision Support. Since you've already set up your ports, there isn't a need to use UPnP or DMZ as there are methods that adjust your port settings as well. The Static IP will assign your console a single IP address so the port forwarding process won't need to be reconfigured. If you need help in the future, feel free to start another thread.