You might be on a CG-NAT network which makes port forwarding impossible. Some ISPs will disable it if you ask (or give you an ipv6 IP which isn’t affected by the issue).
If you go to https://ipinfo.io at home (over wifi or ethernet) and it says your ip is in the 100.64.0.0/10 range, then you are on a CG-NAT network.
This wikipedia article may be helpful. The short answer is that we are running out of public IPv4 addresses so CG-NAT is used so a bunch of users can essentially share 1 (or a few) public IPs. From the router’s perspective, you have a public IP that is actually a private IP in the 100.64.0.0/10 range.
However, not having a real public IP means you have no way for remote devices to directly access your router, so port forwarding won’t work.
You might be on a CG-NAT network which makes port forwarding impossible. Some ISPs will disable it if you ask (or give you an ipv6 IP which isn’t affected by the issue).
How can I go about learning what any of this means and how to look for it?
If you go to https://ipinfo.io at home (over wifi or ethernet) and it says your ip is in the
100.64.0.0/10range, then you are on a CG-NAT network.This wikipedia article may be helpful. The short answer is that we are running out of public IPv4 addresses so CG-NAT is used so a bunch of users can essentially share 1 (or a few) public IPs. From the router’s perspective, you have a public IP that is actually a private IP in the 100.64.0.0/10 range.
However, not having a real public IP means you have no way for remote devices to directly access your router, so port forwarding won’t work.