The Internet Email to Support Diverse Service Environments (Lemonade) Profile
RFC 5550

Approval announcement
Draft of message to be sent after approval:

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Cc: Internet Architecture Board <iab@iab.org>,
    RFC Editor <rfc-editor@rfc-editor.org>, 
    lemonade mailing list <lemonade@ietf.org>, 
    lemonade chair <lemonade-chairs@tools.ietf.org>
Subject: Protocol Action: 'The Lemonade Profile' to Proposed 
         Standard 

The IESG has approved the following document:

- 'The Lemonade Profile '
   <draft-ietf-lemonade-profile-bis-12.txt> as a Proposed Standard

This document is the product of the Enhancements to Internet email to 
Support Diverse Service Environments Working Group. 

The IESG contact persons are Chris Newman and Lisa Dusseault.

A URL of this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-ietf-lemonade-profile-bis-12.txt

Technical Summary

   This document describes a profile (a set of required extensions,
   restrictions and usage modes) of the IMAP and mail submission
   protocols.  This profile allows clients (especially those that are
   constrained in memory, bandwidth, processing power, or other areas)
   to efficiently use IMAP and Submission to access and submit mail.
   This includes the ability to forward received mail without needing to
   download and upload the mail, to optimize submission and to
   efficiently resynchronize in case of loss of connectivity with the
   server.

   The Lemonade profile relies upon several extensions to IMAP and Mail
   Submission protocols.

Working Group Summary
   
  There is WG consensus to publish this document.
           
Document Quality
 
  This document has been through significant review by mail
  client and server vendors, often based on issues with implementing
  the profile, that has resulted in modified base documents and as a
  result modifications in this profile.  In addition, the LEMONADE WG
  has had a liaison relationship with OMA MEM that has resulted in a
  vetting of the features to ensure that the profile is operationally
  useful.  The final document is a result of a significant effort to
  ensure that the mobile email requirements are efficiently realized
  by Internet Mail.

Personnel

  Glenn Parsons is the document shepherd.  Chris Newman has reviewed
  this document for the IESG.

Note to RFC Editor

1) Add "Updates: RFC 4469, RFC 4467" to the header

2) Change the second paragraph of the Abstract from:
OLD:
   The Lemonade profile relies upon several extensions to IMAP and Mail
   Submission protocols.
NEW:
   The Lemonade profile relies upon several extensions to IMAP, Sieve
   and Mail Submission protocols. The document also defines a new IMAP
   extension and registers several new IMAP keywords.

3) In section 7, please change the 2nd paragraph:
OLD:
   Note that the explicit usage of [SUBMIT] means that when opening a
   connection to the submission server, clients MUST do so using port
   587 unless explicitly configured to use an alternate port [RFC5068].
   If the TCP connection to the submission server fails to open using
   port 587, the client MAY then immediately retry using a different
   port, such as 25.  See [SUBMIT] information on why using port 25 is
   likely to fail depending on the current location of the client, and
   may result in a failure code during the SMTP transaction.
NEW:
   When opening a connection to the submission server, clients MUST do
   so using port 587 unless explicitly configured to use an alternate
   port [RFC5068]. (Note that this requirement is somewhat stronger than
   the one specified in [SUBMIT], as [SUBMIT] didn't prescribe the exact
   procedure to be used by submission clients.)
   If the TCP connection to the submission server
   fails to open using port 587, the client MAY then immediately retry
   using a different port, such as 25.
   See [SUBMIT] for information on why using port 25 is
   likely to fail depending on the current location of the client, and
   may result in a failure code during the SMTP transaction.

4) Change the first paragraph of section 8 to read:
OLD:

  Security considerations on Lemonade "forward without download" are
  discussed throughout Section 2.  Additional security considerations
  can be found in [RFC3501] and other documents describing other SMTP
  and IMAP extensions comprising the Lemonade profile.
NEW:
  Security considerations on Lemonade "forward without download" are
  discussed throughout Section 2.  Additional security considerations
  can be found in [RFC3501], [SUBMIT], [SIEVE] and other documents
                           ^^^^^^^^^^^^^^^^^^^
  describing other SMTP, IMAP and Sieve extensions comprising the
                       ^      ^^^^^^^^^
  Lemonade profile.

5) In Section 8.4, change the 1st sentence of the 3rd paragraph to read:

OLD:
   There are two ways to perform "forward without download" based on
   where the message assembly takes place.

NEW:
   This section informatively describes two ways to perform "forward
   without download" based on where the message assembly takes place.

6) Replace section 12 with:

12. Changes since RFC 4550

When compared to RFC 4550, this document adds the following additional
requirements on a Lemonade compliant IMAP server:

A) IMAP extensions:
 BINARY, COMPRESS=DEFLATE, CONTEXT=SEARCH, CONTEXT=SORT, CONVERT,
 ENABLE, ESEARCH, ESORT, I18NLEVEL=1, NOTIFY, QRESYNC, SASL-IR,
 SORT, URL-PARTIAL;

B) IMAP keywords:
 $SubmitPending, $Submitted.

C) Other requirements:

Require any Lemonade compliant IMAP server to support the
CAPABILITY response code.


When compared to RFC 4550, this document adds the following new
requirements on a Lemonade compliant Message Delivery Agents:

Support for the Sieve filtering language, together with the following
Sieve extensions:

ENOTIFY, IMAP4FLAGS, RELATIONAL, VACATION, VARIABLES,
comparator-i;unicode-casemap.


When compared to RFC 4550, this document recommends use of  the DEFLATE
compression method for TLS. All other requirements remain the same.


Additionally, the following changes/improvments were done to RFC 4550
(the list might be incomplete):

A new section with some additiona requirements on Lemonade Mail User
Agents
was added, in particular they are required to support Format=flowed
parameter to to the text/plain media type.

Usage of the $Forwarded IMAP keyword was clarified.

Forward-without-download examples were corrected and extended.

Added a new section describing in-band and out-of-band notifications
from a Lemonade compliant mailstore.