SIM Card in 4G LTE Router

[merm89]

I have an O2 business sim and using it in an TP-Link wireless router which on it's own, works fine.

The issues come when I'm trying to set up port forwarding/virtual servers (as TPLink calls it) to access a CCTV server from the public internet connected to the router via ethernet - I can't seem to get it to work - it just times out.

The CCTV server works fine internally so the device is working. I have tried the IP address as well as assigning it a dynamic DNS.

Also the public IP address shown in the TPLink interface is different to what I get when I search "find my ip" in google.

Is this a configuration issue or an O2 limitation?

Thanks.

[madasaf1sh · Accepted solution]

@merm89 

It is down to the network configuration of o2, which uses a technology known as CGNAT (carrier grade network address translation).

If you want a public IP for the camera, you will have to look at one of the Niche SIM providers such as ScanCom or AAISP