<p>If your router supports NAT-PMP, UPnP, or you have Apple AirPort, Transmission can map its port automatically. Most routers manufactured since 2001 have this feature.
<p>If you don't have a compatible router, it is simple to forward Transmission's port manually. For instructions <ahref="pfrouter.html">click here</a>.</p>
<p>If you don't use a router, and your modem is directly connected to your computer, you'll need to open Transmission's port in the macOS firewall. For instructions <ahref="pffirewall.html">click here</a>.<br><br><em>Note:</em> It is highly recommended you enable the macOS firewall if you are not using a router.</p>
<p>Keep in mind that many DSL modems also function as routers, so port forwarding may still be necessary, even though your computer is directly connected to the modem.</p>