So say I have an arbitrary tcp port 12345 and it's non ssl and I want to put stunnel to secure traffic to it. When stunnel is in front of it does it mean that this port is now tls/ssl only? Or can you still connect to it unencrypted? Basically I want to make sure that this port can only be accessed through ssl/tls and stunel and no other way. Clarification I want to make sure only stunnel port is open. Which is answered in the comments that the unsecured port should be fire-walled but preferably bound to localhost.