Re: [yam] Ambiguities in RFC 5321

[S Moonesamy <sm+ietf at elandsys.com>]

Hi John,
At 12:07 PM 11/13/2009, John Levine wrote:
> In the recent draft, I don't see anything one way or the other about
> dealing with ambiguities in the existing RFC.  While we certainly
> wouldn't want to change the protocol, it looks to me like there are a
> few places where we could clarify the language and, if need be, noting
> implementations have interpreted the language other ways.
>
> In Section 3.1, a server can offer two greetings to a new
> connection, 220 or 554.  The semantics of the 554 are utterly
> unclear.  Plausible interpretations include:
>
> a) This domain has rejected your mail, give up and report the message(s)
> as undeliverable, as though you got the 554 in response to DATA.
>
> 554 YOU ARE BLACKLISTED. FOAD.
>
> b) This server is broken, try others as though you couldn't connect to
> this one.
>
> 554 MY NETAPP IS EMITTING SMOKE. SORRY.
>
> c) This server is sort of broken, try others at the same MX priority
> but not lower.
>
> 554 MY SPOOL DISK IS CURRENTLY FULL. SORRY.
>
> I don't feel strongly about which is the right interpretation, but it
> would be nice to know how to code my mail clients.

I logged this as an issue.

Regards,
S. Moonesamy
YAM WG Secretary