Hello,
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?
Yes you can still seed as well as download. But you are limited and can only upload and download torrent data in swarms that contain peers that are themselves fully connectable (port forwarded).
So say you join a torrent swarm that only contains peers just like you (firewalled, no ports forwarded) then no one will transfer any torrent data with each other. Everyone is stuck waiting for a fully connectable (port forwarded) peer to join that swarm.