On 12/1/2015 6:05 AM, Tony Finch wrote: > Ted Lemon <[email protected]> wrote: >> Monday, Nov 30, 2015 6:02 PM Dave Crocker wrote: >>> On 11/30/2015 2:51 PM, Ted Lemon wrote: > >>>> Why would I be relaying mail on? Only for a mailing list. >>> >>> The most obvious is mailbox aliasing, such as for vanity addresses such >>> as university alumni associations provide. >> >> That's a mailing list with one subscriber. Same scenario. > > Not really. Mailing lists have very different administrative behaviour to > aliases - they change the return path to an administrative address when > forwarding the message whereas aliases do not. RFC 5321 section 3.9.
Yes. And further... They typically also have very different formal -- that's meant as 'official', not 'math' -- semantics. Alias behavior tends to be /very/ close to pure relaying. It changes very little in the message, other than the rfc5321.Rcpt-To address. Mailing lists tend to make massive changes to the original message; they are taking formal delivery of the message and then post a new message. For end users, the view is of a single message from original author to final recipient. To the email infrastructure it is two (or more) post/deliver sequences. Folks seeking to discuss email at this level should consider becoming familiar with RFC 5598. It will make careful discussion of email behavior a lot more consistent... d/ -- Dave Crocker Brandenburg InternetWorking bbiw.net _______________________________________________ Shutup mailing list [email protected] https://www.ietf.org/mailman/listinfo/shutup
