IETF Logo Mail Archive

Re: [ietf-smtp] Quoted-Printable-8bit

John Levine <johnl@taugh.com> Tue, 30 March 2021 01:00 UTC

Return-Path: <johnl@iecc.com>
X-Original-To: ietf-smtp@ietfa.amsl.com
Delivered-To: ietf-smtp@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id B66423A27A6 for <ietf-smtp@ietfa.amsl.com>; Mon, 29 Mar 2021 18:00:36 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.851
X-Spam-Level:
X-Spam-Status: No, score=-1.851 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HEADER_FROM_DIFFERENT_DOMAINS=0.249, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=iecc.com header.b=daAijYW0; dkim=pass (2048-bit key) header.d=taugh.com header.b=Uahns0AP
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9yoSUbHq2nDU for <ietf-smtp@ietfa.amsl.com>; Mon, 29 Mar 2021 18:00:31 -0700 (PDT)
Received: from gal.iecc.com (gal.iecc.com [IPv6:2001:470:1f07:1126:0:43:6f73:7461]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 08BE33A27DB for <ietf-smtp@ietf.org>; Mon, 29 Mar 2021 18:00:30 -0700 (PDT)
Received: (qmail 99653 invoked from network); 30 Mar 2021 01:00:28 -0000
DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=iecc.com; h=date:message-id:from:to:cc:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:cleverness; s=18542.6062782c.k2103; bh=WkCTd0WdApoRW5vMXATX6HBpt+6o73HdSt1dmSVzYx4=; b=daAijYW08KAKVwEhAWQRcfzkTmo2Lj5MfuOCSSz/gvkOXf/jPpRryuDJ9nz9w7mEMcxh45NYaQURTD2Qvw5HQj6qv1Ry7oqcq2zaCzlPe2pAT8Ye2fpF5jNrPlxmG/rKA+PiFy9sL1092CchroP1yIiTtp3BboCb9Ryop/mr7Sq061e77QgF8C/dW9fcf/699Y6qqq7uD0sb+UI1/sjPISN4zmi2oLot7zbPsqvp10WQYcwEpPtjwKZf+jTBiiGN55o6uGxwJi/KQguDvEEakgJbDGekOcFiTcQcazGiR+PCiLSfueqXk4dJEsjTaNcKFKa6kasDn1Y8k3ki6zPd0w==
DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=taugh.com; h=date:message-id:from:to:cc:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:cleverness; s=18542.6062782c.k2103; bh=WkCTd0WdApoRW5vMXATX6HBpt+6o73HdSt1dmSVzYx4=; b=Uahns0APMu7WC9DiF57ItRPQU/8pbXXGMXVyAWnJDwV4RWVNKuHu8QKgl9YABD6z0yYEtGzb4w+Lxwh3OIDqwPTBxCMHDhPhqiimGrfZS6lmy5k0t1lvAvRvrPxnDRAz3TbIZTX4KGllFeVspyoSmHPdpOKkA5SDoqm7uNR90e2/L389+2nVnJ0J9MgtdnV0PmGtdefnVvLQxUl1zzJTnQcmLqu0ZgBOvITtKDxdABfoWRfYgUT7tW/M9xuKRnV0uh2y2vGWYGebx24Ex4gPkK5NHIu0UE58nIW0MSp7dnF5sO73VnMSUC98zRl+FabBtZ4N6mxf7vNd0sc5fAhGWw==
Received: from ary.qy ([IPv6:2001:470:1f07:1126::78:696d:6170]) by imap.iecc.com ([IPv6:2001:470:1f07:1126::78:696d:6170]) with ESMTPS (TLS1.2 ECDHE-RSA AES-256-GCM AEAD) via TCP6; 30 Mar 2021 01:00:28 -0000
Received: by ary.qy (Postfix, from userid 501) id F13AD718E3C0; Mon, 29 Mar 2021 21:00:27 -0400 (EDT)
Date: Mon, 29 Mar 2021 21:00:27 -0400
Message-Id: <20210330010027.F13AD718E3C0@ary.qy>
From: John Levine <johnl@taugh.com>
To: ietf-smtp@ietf.org
Cc: mrsam@courier-mta.com
In-Reply-To: <cone.1617061398.771367.57281.1004@monster.email-scan.com>
Organization: Taughannock Networks
X-Headerized: yes
Cleverness: minimal
Mime-Version: 1.0
Content-type: text/plain; charset="utf-8"
Content-transfer-encoding: 8bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/ietf-smtp/We5rY1leu3tW-YWfAoRRrt1gyH8>
Subject: Re: [ietf-smtp] Quoted-Printable-8bit
X-BeenThere: ietf-smtp@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "Discussion of issues related to Simple Mail Transfer Protocol \(SMTP\) \[RFC 821, RFC 2821, RFC 5321\]" <ietf-smtp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ietf-smtp>, <mailto:ietf-smtp-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ietf-smtp/>
List-Post: <mailto:ietf-smtp@ietf.org>
List-Help: <mailto:ietf-smtp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ietf-smtp>, <mailto:ietf-smtp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 30 Mar 2021 01:00:37 -0000

It appears that Sam Varshavchik  <mrsam@courier-mta.com> said:
>So, what is the answer to the same question, for BINARYMIME? This is mostly  
>conjecture, but I'd say that email implementations tend to fall into two  
>broad categories.

CHUNKING and BINARYMIME were in RFC 1830.

RFC 2045 says:

   Mail transport for unencoded 8bit data is defined in RFC 1652.  As of
   the initial publication of this document, there are no standardized
   Internet mail transports for which it is legitimate to include
   unencoded binary data in mail bodies.  Thus there are no
   circumstances in which the "binary" Content-Transfer-Encoding is
   actually valid in Internet mail. ...

I get the impression that BINARYMIME was a placeholder they threw in
with the hope that some other kind of framing would come along. The
advantage of BDAT over DATA for 8BITMIME is pretty modest, and can
even be negative for the implementations that send small 8K BDAT
chunks.

The fact that nothing like quoted-unprintable has ever gotten any traction
tells me that even the overhead of base64 vs 8BITMIME isn't something people
care about.

R's,
John

v2.23.0 | Report a Bug | By Email