topic Re: Request for Public IPv4 (CGNAT Opt-Out) in Broadband

Request for Public IPv4 (CGNAT Opt-Out)

Ry13 — Sun, 08 Mar 2026 12:43:15 GMT

I need to opt out of CGNAT and be assigned a public IPv4 address. I require inbound connections for remote access. A dynamic public IPv4 is fine.

Re: Request for Public IPv4 (CGNAT Opt-Out)

cookiemonsteruk — Sun, 08 Mar 2026 12:57:05 GMT

@Ry13

I assume you have the white sky max hub

Sky uses map-t which is stateless and can be acheived by invoking a port forwarding rule or by calling sky

Re: Request for Public IPv4 (CGNAT Opt-Out)

Chrisee — Sun, 08 Mar 2026 12:58:58 GMT

@Ry13 Sky only use MAP-T (technically not CGNAT but achieves simial outcome) on their white Sky hubs anf other hub or third party router should not be affected. You can switch the share from 8;1 to 1:1 by switching UPNP on as explained here UPnP set up

Alternatively setting up port forwarding achieves the same outcome.

Sky do not routinely switch off MAP-T on request.

Re: Request for Public IPv4 (CGNAT Opt-Out)

Ry13 — Mon, 09 Mar 2026 16:45:24 GMT

Hi, thanks for the explanation — really appreciate you taking the time to clarify it.

I wasn’t aware Sky were using MAP-T rather than traditional CGNAT, so that makes a lot more sense now. From what you’ve said it sounds like the behaviour I’m seeing is likely just down to the shared IPv4 / port allocation rather than an actual fault with the connection.

I’m going to try enabling UPnP on the hub as you suggested and see if that improves things before looking at manual port forwarding.

One quick question though — I’ve also got an Xbox and a PS5 on the network. In your experience could enabling UPnP cause any issues with those (for example NAT type problems or both consoles trying to use the same ports), or should it generally help them as well?

Thanks again for pointing me in the right direction.

Re: Request for Public IPv4 (CGNAT Opt-Out)

Chrisee — Mon, 09 Mar 2026 17:09:14 GMT

@Ry13 UPnP should not cause issues with game play. It is less secure than having it off but the risks for domestic networks are pretty low. When I had the older Sky hubs UPnP was on by default unlike the white hubs which default to off.