I am using qbittorrent for torrenting and my ISP has refused to open up firewall because of fucking "security" reasons. however I can still seed the torrent how is that possible? I mean all the incoming connections should be blocked right? isn't it how firewall works?
You commented that it's "super weird and invasive" for an ISP to "firewall" listening ports. It just so happens that CGNAT also has the same effect and is super commonly used right now.
Yes I know what's preventing me from opening ports. I also called my ISP they said we can't open the firewall so the incoming connections will be blocked.
Ipv4 shortage lead to a lot of IPS adopting CG-NATs where they are sharing one exit IPv4 for multiple end users and that's why opening a port on the end user side won't do a thing as your just opening a port in the ISP Network and not to the Internet