I have the Huawei B5142 device from my carrier. This device is the source of internet connection to my home's router. My PS4 is wirelessly connected directly to the Huawei device, bypassing my router. The Huawei device has a public IP address such as 188.8.131.52, and an internal address such as 10.15.3.11, my PS4 has a standard 192.168.1.50 address reserved for its MAC address.
I should note that my ISP currently uses NAT444 / LSN (Large Scale NAT), however the public and router internal addresses (184.108.40.206 and 10.15.3.11) are static allocations from my ISP's network.
I have de-activated the router's built-in firewall and DMZ'd my PS4's internal address (192.168.1.50), yet I still get a moderate (Type 2) NAT result.
Is there something else I can try or is an open NAT type even possible behind CGN?