Hector Santos wrote:
Under most scenarios, servers SHOULD use the same reply
code for each multiline response line when it is going to
be displayed at the same time. However there are scenarios
(Keep Alive Client Timeout issues) where servers MAY use
"150-" as an alternative reply code in a continuation line
when the server needs to issue a heartbeat to keep the client
alive during unsual delayed backend processing:
I don't like that. There's no reason to assume that parts of a multiline
response will have any effect on the client timeout. It might not reset
its timer just because it gets part of a reply back. Maybe many current
implementations do, but that's just good luck.
I believe that a proper negotiated ESMTP extension for "keepalive"
intermediate replies should be developed. We shouldn't try to hack
something in.
Regards,
David.