On Thu, Mar 5, 2015 at 12:02 PM, The IESG <iesg-secretary(_at_)ietf(_dot_)org>
wrote:
The IESG has received a request from an individual submitter to consider
the following document:
- 'SMTP 521 and 556 Reply Codes'
<draft-klensin-smtp-521code-05.txt> as Proposed Standard
The IESG plans to make a decision in the next few weeks, and solicits
final comments on this action. Please send substantive comments to the
ietf(_at_)ietf(_dot_)org mailing lists by 2015-04-02. Exceptionally, comments
may be
sent to iesg(_at_)ietf(_dot_)org instead. In either case, please retain the
beginning of the Subject line to allow automated sorting.
Abstract
This memo defines two Simple Mail Transfer Protocol (SMTP) reply
codes, 521 and 556. The 521 code was originally described in an
Experimental RFC in 1995 and is in wide use, but has not previously
been formally incorporated into SMTP. The 556 code was created for
RFC-nullMX. These codes are used to indicate that an Internet host
does not accept incoming mail at all (not just under particular
circumstances).
I support publication of this work. I have the following minor comments:
Section 2 says that a client trying to talk to a server that provides no
SMTP service will eventually time out. That's not universally true; trying
to talk to a server that's up but not offering SMTP service can also cause
an immediate error if an RST comes back in reply to the SYN because there's
nothing listening on port 25.
In Section 3, there's an errant semicolon.
Should Section 5.1 also add 521 to the list of valid connection termination
conditions in Section 3.8 of RFC5321?
-MSK