SM wrote:
IMV, it depends on the client, is it a MUA client? an backend server
list distribution?
MUAs fall under SUBMIT and do not use the same retry strategy as SMTP
clients.
Explain why (Falls Under SUBMIT) and why it could not use the same,
similar or simpler retry strategy?
SUBMIT requires authentication which is not a required setup for MUA
software. The server dictates this. Not the MUA. So outside of
authentication, from the POV of the server, it wouldn't know the
difference and the MUA's MTA component is expected to behave just like
any other MTA.
Of course, the MUA are not generally considered mailing list material
but I have a few customers who use their MUA for the purposes of
sending large CC/TO list. Don't ask why, I've been trying to convince
them to use the list server they already have but don't use. :-)
The difference between MUAs and SMTP client is that the former can
revert back to the user for input.
Agreed, but there is no reason a MUA designer could not automate it
just like a normal backend automated MTA. I see no reason why a MUA
could not offer these options or something simple like them:
[X] Continue trying for __X_ attempts
Retry every X hours|Minutes
[X] Queue 4xx Failures
[X] Remove, but do not stop transactions with 5xx RCPT rejections
and still make it so its "Friendly" for users.
Right?
Its not unreasonable, there were technologies originally designed for
end users, eventually been automated for networking. In fact, I will
suggest many online hosting systems started as interactive user online
access/point systems, and then someone added a mail point transport or
frontend to it :-)
--
Sincerely
Hector Santos, CTO
http://www.santronics.com
http://santronics.blogspot.com