Message-Id: <199510040429.AAA26883@wilma.cs.utk.edu>
From: Keith Moore <moore@CS.UTK.EDU>
To: drums@CS.UTK.EDU
cc: moore@CS.UTK.EDU
Subject: Re: What's the sender header for? 
In-reply-to: Your message of "Tue, 03 Oct 1995 23:08:07 CDT."
             <9510040408.AA14106@dogie.macc.wisc.edu> 
Date: Wed, 04 Oct 1995 00:28:57 -0400
Sender: moore@CS.UTK.EDU

> Let's not forget that RFC822 is supposed to be a protocol that only
> specifies the format of messages, and, as such, does not assume the
> use of any particular transport protocol.  I.e. we're going to have
> to make the meaning and usage of Return-Path: clear for the folks
> that don't have an envelope with a return address.
> 
> Keith says that there's no clear interface 'tween RFC822 and RFC821.
> In light of the above paragraph, I'm going to lightheartedly disagree
> and say that there is too.  The interface says that they're independent
> and that the only thing you do after a positive reply to the DATA
> command is send a bunch of RFC822 bytes; period.  [Ohmygosh; an SMTP pun.]

That part is pretty well agreed on, though not everyone will
agree that the SMTP DATA is expected to conform to RFC 822.
(especially when using the SEND, SAML, or SOML commands)

What's not completely clear is how you generate an SMTP envelope 
if you start with an RFC 822 message (For instance, how do you
handle Bcc headers?  And more to the point, where does MAIL
FROM come from?  Do you generate it from the Sender field?)

> I sure don't see how you can claim that sending bounces to Sender: is
> breakage since it's specifically allowed by RFC822.  It'll be breakage
> if we eliminate this, but it isn't now.

RFC 1123 makes it fairly clear that bounces to the MAIL FROM
address (or lacking that, to the Return-Path header), though 
it doesn't seem to prohibit sending copies of the bounced
message to other places.

Keith