I was looking at the packets hitting my server and was wondering.....
When an email is sent from Server1 to MyServer, are the packets always sent from Server1:25 to a random port on MyServer...or sent from a random port on Server1 to MyServer:25
It seems like it happens both ways. But if my server is listening on port 25 for SMTP, then why can it accept SMTP on a different port?
The same question goes for MyServer sending out emails. Why does it sometimes send from port 25, and other times send TO port 25?