John -- It's a pity to say this about such a nicely-written
draft, but I fear this proposal comes remarkably close to
maximizing the cost/benefit ratio. When you consider
distributed costs of testing and deployment, I would bet that
implementing this proposal would cost at *least* 50% of what
it would cost to deploy a far more radical set of changes to
the email infrastructure.
What we were discussing in Minneapolis was a
once-in-a-generation scale of protocol reform. I think we
should think big, because there is a large fixed cost to
pushing any structural change through the entire Internet
community. I'm particularly concerned that you seem to be
punting on internationalization -- I can't see putting much
energy into *any* major reform that doesn't address the most
widely-perceived failing of the current system.
At root, what I don't buy is the notion that, in this case, we
can take an incremental approach to radical change. The
Wright Brothers didn't learn to fly by practicing the high
jump, and I don't think we're going to clean up email by
creating a new architectural entity (the extended envelope)
that only works in ASCII.
Now, if the extended envelope could be done completely in
UTF-8, with a coevolutionary model for son-of-822 header
fields and binary body transport, now *that* would be a more
compelling story. Delivery tracing, internationalization, and
binary transport would be a nice trio of goals for a
next-generation email system. I can certainly think of a few
others, though. -- Nathaniel
On Friday, January 23, 2004, at 04:53 PM, John C Klensin
wrote:
The draft posted/described in the attached is a bizarre idea,
partially to see if it is possible to consider a radical
solution to an increasingly troublesome problem, and
partially to see if the supportive comments about "Email NG"
in Minneapolis were really serious.
I am not at all convinced that it is a _good_ idea, only
that, if we are talking about radical changes to the mail
infrastructure to support various extended services, this is
the sort of "clean up the warts that get in the way" option
we might want to consider.
And even if it were a good idea, some of the details are
probably not right -- if this looks like it received a day's
thought, you would probably be guessing much too high.
Discussion should probably go to the SMTP list; IMAA is
copied only because this could interact a bit with some of
the "UTF-8 header" discussions.
john
From: Internet-Drafts@xxxxxxxx
Date: Fri Jan 23, 2004 3:59:11 PM America/Detroit
To: IETF-Announce: ;
Subject: I-D ACTION:draft-klensin-email-envelope-00.txt
Reply-To: Internet-Drafts@xxxxxxxx
A New Internet-Draft is available from the on-line
Internet-Drafts directories.
Title : A Cleaner SMTP Envelope for Internet Mail
Author(s) : J. Klensin
Filename : draft-klensin-email-envelope-00.txt
Pages : 0
Date : 2004-1-23
During the last few years, a number of proposals for
extensions or improvements to email have run into trouble
with a side-effect of mail relaying. In the current Internet
Mail model, every SMTP server is required to break strict
layering by inserting one or more additional 'trace' headers
into the message headers which are actually part of the SMTP
payload. Since the headers are altered in transit,
header-signing is not an available option, various anti-spam
and internationalization strategies are infeasible or much
more complex, and so on. This document proposes to change the
Internet mail model to place the in-transit trace information
in the envelope, removing the requirement that relaying
systems modify the message payload.
A URL for this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-klensin-email-envel
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