John Hardin a écrit : > On Thu, 12 Feb 2009, Ned Slider wrote: > >> John Hardin wrote: >> >>> Huh? My mail server relays messages from my home network to the entire >>> world. I'm not talking about custom relays. >> >> I think I'm going to have to concede this point to you though on >> relays, although one could argue that you don't really need to be >> relaying mail from your home network through your mail server, you >> could just connect to your mail server directly from your MUA. Having >> an additional relaying MTA in the middle is what introduces the >> potential for problems but life isn't always simple. > > How, from the POV of my hosted domain mail server, is a SMTP connection > from my MTA on my home network different from a connection from my MUA > on my home network? >
an oubtound relay "knows the sender". it is easier to control spam in this case. and if not, you can still enforce the sender domain, so that bounces can only go to your users. so it's your own backscatter, and is not a problem for the rest of us. an inbound relay (what Ned meant by "relay to") is different: you have no control over clients or senders. so the final server should never reject mail from this relay (except in rare cases that can't create scatter storms).
