Subject: [lemonade] Lemonade Profile Comments

From: "Vaudreuil, Greg M (Greg)" <[email-masked]>
Date: Tue, 8 Mar 2005 13:31:30 -0600

Lemonade Profile Comments

In general, this document is written more as a tutorial than a standards document. I'd like to suggest specific "lemonade servers must support" kind of language.  The value to the profile document is to have a marketing-ready tag to slap on a large chunk of interrelated new and pre-existing standards.  

This profile is also intended to support multi-media messaging and certain entrenched unified messaging concepts.  In particular, a system supporting the Lemonade profile must support a set of miscellaneous extensions necessary to make such an experience possible.

- Future Delivery.  The diverse client can't send the message upon it's appointed time if it is in bad coverage, or otherwise doing something else interesting.  Needs server-side support as provided in draft-ietf-lemonade-futuredelivery.

- Message context.  The clients need to present the proper icon's, message counts, and/or views based on the historical context of the message without downloading the entire message header for each message in a mailbox.  To do this, the LMTP deposit process is expected to set a new IMAP flag to indicate the message context.  The client has ready access to flags and can use them for local processing without downloading all the message headers.

- Security.  I understood an earlier agreement that the profile would have a minimum encryption and authentication scheme adequate to permit reasonable enterprises to allow a limited capability device to connect through a firewall, authenticate, and retrieve messages without use of a VPN client and the necessary overhead associated with establishing a VPN session.

- Compression. I understood a consensus around using StartTLS with possibly a null ciphers to achieve transport-level compression.  We had some discussions from Nortel about the relative values of such, but my recollection was general agreement that this would be a good and required thing for a server to support.  I don't think this is "future work" in the sense of a later document.

Greg V.

_______________________________________________
lemonade mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/lemonade

---

From: "Stephane H. Maes" <[email-masked]>
Date: Tue, 8 Mar 2005 11:53:33 -0800

Greg

Thanks for the comments.

I have added in line marked <SM> ... </SM>

Stephane
_____
Stephane H. Maes, PhD,
Director of Architecture - RTCC & Mobile, Oracle Corporation.
Ph: +1-203-300-7786 (mobile/SMS); Fax / Office UM: +1-650-607-6296.
e-mail: [email-masked]
IM: shmaes (AIM/Y!/skype) or [email-masked] (MSN Messenger)

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of Vaudreuil, Greg M (Greg)
Sent: Tuesday, March 08, 2005 11:32 AM
To: [email-masked]
Subject: [lemonade] Lemonade Profile Comments

<SM> Will try for next version. </SM>

<SM> Hmm how does it access the server then if in bad coverage? Isn't it simply client side storage? </SM>

<SM> Can you elaborate. </SM>

<SM> 
As I understand this will be discussed for the next version more focused on profile and when in charter. (See ppt for lemonade 61.5 interim meeting) 

I agree that it is critical.</SM>

<SM> This is not my recollection. It was shown that application compression can sometimes be more efficient and sometimes buys little depending on the type of e-mail... 

Also this is material for future work (again see 61.5 intermediate meeting ppt).

Also discussions of the point above (firewalls / intermediaries) may affect this too.</SM>

Greg V.

---

From: Randall Gellens <[email-masked]>
Date: Wed, 9 Mar 2005 09:18:31 -0800

Here are my comments.  See lines starting with ">>>".

                           <Lemonade Profile>             February 2005

Lemonade
Internet Draft: Lemonade Profile                             S. H. Maes
Document: draft-ietf-lemonade-profile-01.txt                A. Melnikov
Expires: August 2005                                      February 2005

                              Lemonade Profile

Status of this Memo

    This document is an Internet-Draft and is subject to all provisions
    of Section 10 of RFC2026. By submitting this Internet-Draft, each
    author represents that any applicable patent or other IPR claims of
    which he or she is aware have been or will be disclosed, and any of
    which he or she become aware will be disclosed, in accordance with
    RFC 3668.

    Internet-Drafts are working documents of the Internet Engineering
    Task Force (IETF), its areas, and its working groups.  Note that
    other groups may also distribute working documents as Internet-
    Drafts.

    Internet-Drafts are draft documents valid for a maximum of six months
    and may be updated, replaced, or obsoleted by other documents at any
    time.  It is inappropriate to use Internet-Drafts as reference
    material or to cite them other than as "work in progress."

    The list of current Internet-Drafts can be accessed at
         http://www.ietf.org/ietf/1id-abstracts.txt

    The list of Internet-Draft Shadow Directories can be accessed at
         http://www.ietf.org/shadow.html.

Abstract

    This document describes the Lemonade profile to allow clients to
    submit new email messages incorporating content which resides on
    locations external to the client ("forward without download").
>>>  ...describes a profile (a set of required extensions, restrictions,
>>>  and usage modes) of mail protocols such as IMAP and Submission.
>>>  This profile allows clients (especially those that are constrained
>>>  in memory, bandwidth, processing power, or other areas) to
>>>  effeciently 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 have media attached to a
>>>  message converted if required, and to more efficiently maintain
>>>  a synchronized cache of received messages.

    The Lemonade profile relies upon extensions to other protocols;
>>>                                                ^^^^^ -> "various"
    specifically URLAUTH, CATENATE, Lemonade Command Extensions in the
    IMAP protocol [RFC 3501] and BURL in the SUBMIT protocol [RFC 2476].

    In addition, the Lemonade profile contains Lemonade Command
    extensions for quick reconnect and media conversion.
>>>  No, these must not be in a profile document, they must be in
>>>  their own documents and referenced here.

Conventions used in this document

Maes                    Expires - August 2005                [Page 1]


                           <Lemonade Profile>             February 2005

    In examples, "M:", "I:" and "S:" indicate lines sent by the client
    messaging user agent, IMAP e-mail server and submit server
    respectively.

    The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
    "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
    document are to be interpreted as described in [RFC2119].

Table of Contents

    Status of this Memo...............................................1
    Abstract..........................................................1
    Conventions used in this document.................................1
    Table of Contents.................................................2
    1. Introduction...................................................2
    2. Forward without download.......................................3
       2.1. Motivations...............................................3
       2.2. Message Sending Overview..................................3
       2.3. Traditional Strategy......................................4
       2.4. Step by step description..................................4
       2.5. Additional Considerations.................................8
       2.6. The fcc problem...........................................8
    3. Media Conversion...............................................9
       3.1. Introduction..............................................9
       3.2. Static media conversion...................................9
       3.3. Conversion of streamed media..............................9
       3.4. Quick Reconnect scheme....................................9
    4. Future work...................................................10
    Security Considerations..........................................10
    References.......................................................10
    Version History..................................................12
    Acknowledgments..................................................12
    Authors Addresses................................................12
    Intellectual Property Statement..................................12
    Full Copyright Statement.........................................13

1.
    Introduction

    Lemonade provides enhancements to Internet email to support diverse
    service environments.

    This document describes the lemonade profile that includes:
       - The Lemonade Pull Model that describes exchanges between
         Lemonade Agents to allow clients to submit new email messages
         incorporating content which resides on locations external to
         the client and allow forward without download.
       - Media conversion

Maes                    Expires - August 2005                [Page 2]


                           <Lemonade Profile>             February 2005

       - Quick reconnect

    The organization of this document is as follows.  Section 2 describes
    the Lemonade Pull Model. Section 3 Section 3 describes the Media
    Conversion. Section 4 describes quick reconnect

2.
   Forward without download

2.1.
     Motivations

    The advent of client/server email using the [RFC3501] and [RFC2821]
    protocols has changed what formerly were local disk operations to
    become excessive and repetitive network data transmissions. This is
>>>        ^^^^^^^^^^^^^^^^^^^^^^^^ <<delete>>
    an onerous burden for clients operating over low-bandwidth and/or
>>>  ^^^^^^^^^ <<delete>>
    high-latency links.

    The Lemonade Pull Model makes use of the [BURL] SUBMIT extension to
    enable access to external sources during the submission of a message.
    In combination with the IMAP [URLAUTH] extension, inclusion of
    message parts or even entire messages from the IMAP mail store is
    possible with a minimal trust relationship between the IMAP and
    SUBMIT servers.

    Pull has the distinct advantage of maintaining one submission
>>>^^^^ -> "This approach"
>>>              ^^^^^^^^ <<<delete 'distinct'>>>
    protocol, and thus avoids the risk of having multiple parallel and
    possible divergent mechanisms for submission.  Furthermore, by
    keeping the details of message submission in the SUBMIT server, the
    Lemonade Pull Model can work with other message retrieval protocols
    such as POP, NNTP, or whatever else may be designed in the future.

2.2.
     Message Sending Overview

    The act of sending an email message is best thought of as involving
    multiple steps: initiation of a new draft, draft editing, message
    assembly, and message submission.

    Initiation of a new draft and draft editing takes place on the MUA.
    Frequently, users choose to save more complex and/or time-consuming
>>>                                                      ^^^^^^^^^^^^^^
>>>  (What is a "time-consuming message"?)
    messages on an [RFC3501] server (via the APPEND command with the
    \Draft flag) for later recall by the MUA and resumption of the
    editing process.

    Message assembly is the process of producing a complete message from
    the final revision of the draft and external sources.  At assembly
    time, external data is retrieved and inserted in the message.

    Message submission is the process of inserting the assembled message
    into the [RFC2821] infrastructure, typically using the [RFC2476]
    protocol.

Maes                    Expires - August 2005                [Page 3]


                           <Lemonade Profile>             February 2005

2.3.
     Traditional Strategy

    Traditionally, messages are initiated, edited, and assembled entirely
    within an MUA, although drafts may be saved to an [RFC3501] server
    and later retrieved from the server.  The completed text is then
    transmitted to an MSA for delivery.

    There is often no clear boundary between the editing and assembly
    process.  If a message is forwarded, its content is often retrieved
    immediately and inserted into the message text.  Similarly, once
    external content is inserted or attached, the content is usually
    retrieved immediately and made part of the draft.

    As a consequence, each save of a draft and subsequent retrieve of the
    draft transmits that entire (possibly large) content, as does message
    submission.

    In the past, this was not much of a problem, because drafts, external
    data, and the message submission mechanism were typically located on
    the same system as the MUA.  The most common problem was running out
    of disk quota.

2.4.
     Step by step description

Maes                    Expires - August 2005                [Page 4]


                           <Lemonade Profile>             February 2005

    The model distinguishes between a Messaging User Agent (MUA), an
    IMAPv4Rev1 Server ([RFC3501]) and a submit server ([RFC2476]), as
    illustrated in Figure 1.

         +--------------------+               +--------------+
         |                    | <------------ |              |
         |     MUA (M)        |               | IMAPv4 Rev1  |
         |                    |               |  Server      |
         |                    | ------------> | (Server I)   |
         +--------------------+               +--------------+
                ^  |                             ^     |
                |  |                             |     |
                |  |                             |     |
                |  |                             |     |
                |  |                             |     |
                |  |                             |     |
                |  |                             |     v
                |  |                          +--------------+
                |  |------------------------->|              |
                |                             |   Submit     |
                |-----------------------------|   Server     |
                                              |  (Server S)  |
                                              +--------------+
                      Figure 1: Lemonade Pull Model

    The Lemonade Pull Model allows a Messaging User Agent to compose and
    forward an e-mail combining fragments that are located in an IMAP
    server, without having to download these fragments to the server.

    In the [BURL]/[CATENATE] variant of the pull strategy, messages are
    initially composed and edited within an MUA.  The [CATENATE]
    extension to [RFC3501] is then used to upload the message to the IMAP
    server and assemble it, and finally a [URLAUTH] format URL is given
    to a [RFC2476] server with the [BURL] extension for submission.

    The flow involved to support such a use case consists of:
       M: {to I -- Optional} The client connectects to the IMAP server
      and IMAP Fetch of body structures and UIDs (See [RFC3501])

      Example:
            M: A0051 FETCH 161 (UID BODYSTRUCTURE)
            I: * 161 FETCH (UID 25627 BODYSTRUCTURE (("TEXT" "PLAIN"
      ("CHARSET" "US-ASCII") NIL
               NIL "7BIT" 1152 23)("TEXT" "PLAIN" ("CHARSET" "US-ASCII"
      "NAME"
               "cc.diff")
               "<[email-masked]>" "Compiler
      diff"

Maes                    Expires - August 2005                [Page 5]


                           <Lemonade Profile>             February 2005

               "BASE64" 4554 73) "MIXED"))
            I: A0051 OK completed

       M: {to I} The client invokes CATENATE (See [CATENATE] for details
      of the semantics and steps š this allows the MUA to create messages
      on the IMAP using new data combined with body structure already
      present on the IMAP server.

      <<Editors note: Draft editing/catenation is omitted for now>>

         M: A0052 CATENATE Sent FLAGS (\Seen $MDNSent) TEXT {738}
         I: + Ready for literal data
         M: Return-Path: <[email-masked]>
         M: Received: from [127.0.0.2]
         M:           by rufus.example.org via TCP (internal) with
      ESMTPA;
         M:           Thu, 11 Nov 2004 16:57:07 +0000
         M: Message-ID: <[email-masked]>
         M: Date: Thu, 12 Nov 2004 16:57:05 +0000
         M: From: Bob Ar <[email-masked]>
         M: X-Accept-Language: en-us, en
         M: MIME-Version: 1.0
         M: To: [email-masked]
         M: Subject: About our holiday trip
         M: Content-Type: multipart/mixed;
         M:               boundary="------------030308070208000400050907"
         M:
         M: --------------030308070208000400050907
         M: Content-Type: text/plain; charset=us-ascii; format=flowed
         M: Content-Transfer-Encoding: 7bit
         M:
         M: Our travel agent has sent the updated schedule.
         M:
         M: Cheers,
         M: Bob
         M: --------------030308070208000400050907
         M:  URL "imap://imap.example.org/INBOX;UIDVALIDITY=385759045/;
            UID=25627;Section=1.2" TEXT {44}
         I: + Ready for literal data
         M: --------------030308070208000400050907--
         M:
         I: A0052 OK [APPENDUID 387899045 45] CATENATE Completed
         M: A0053 UID STORE XXX +FLAGS.SILENT ($Forwarded)
         I: A0053 OK STORE completed

      << Editors note: Recommend UIDPLUS extension š especially useful
      when appending messages to a non-selected mailbox>>

Maes                    Expires - August 2005                [Page 6]


                           <Lemonade Profile>             February 2005

       M: {to I} The client uses GENURLAUTH command to request and
      URLAUTH URL (See [URLAUTH]).
       I: {to M} The IMAP server returns URLAUTH URL suitable for later
      retrieval with URLFETCH (See [URLAUTH] for details of the semantics
      and steps).

      M: A0054 GENURLAUTH
      "imap://[email-masked]/Sent;UIDVALIDITY=387899045/;uid=45/;urla
      uth=submit+bar" INTERNAL
             I: * GENURLAUTH
      "imap://[email-masked]/Sent;UIDVALIDITY=387899045/;uid=45/;urla
      uth=submit+bar:internal:91354a473744909de610943775f92038"
             I: A0054 OK GENURLAUTH completed

       M: {to S} The client connects to the submission server and starts
      a new mail transaction. It uses BURL to let the submit server fetch
      the content of the message from the IMAP server (See [BURL] for
      details of the semantics and steps š this allows the MUA to
      authorize the submit server to access the message composed as a
      result of the CATENATE step).

      M: EHLO potter.example.org
         S: 250-owlry.example.com
         S: 250-8BITMIME
         S: 250-BURL imap
         S: 250-AUTH PLAIN
         S: 250-DSN
         S: 250 ENHANCEDSTATUSCODES
         M: AUTH PLAIN aGFycnkAaGFycnkAYWNjaW8=
         S: 235 2.7.0 PLAIN authentication successful.
         M: MAIL FROM:<[email-masked]>
         S: 250 2.5.0 Address Ok.
         M: RCPT TO:<[email-masked]>
         S: 250 2.1.5 [email-masked] OK.
         M: BURL
      imap://[email-masked]/Sent;UIDVALIDITY=387899045/;uid=45/;urlau
      th=submit+bar:internal:91354a473744909de610943775f92038 LAST

       S: {to I} The submission server uses URLFETCH to fetch the message
      to be sent (See [URLAUTH] for details of the semantics and steps.
      The so-called "pawn-ticket" authorization mechanism uses a URI
      which contains its own authorization credentials.).
       I: {to S} Provides the message composed as a result of the
      CATENATE step).

      Submission server opens IMAP connection to the IMAP server:

             I: * OK [CAPABILITY IMAP4REV1 URLAUTH] example.com IMAP
      server ready

Maes                    Expires - August 2005                [Page 7]


                           <Lemonade Profile>             February 2005

             S: a001 LOGIN submitserver secret
             I: a001 OK submitserver logged in
             S: a002 URLFETCH "
      imap://[email-masked]/Sent;UIDVALIDITY=387899045/;uid=45/;urlau
      th=submit+bar:internal:91354a473744909de610943775f92038"
             I: * URLFETCH "
      imap://[email-masked]/Sent;UIDVALIDITY=387899045/;uid=45/;urlau
      th=submit+bar:internal:91354a473744909de610943775f92038" {15065}
             ...message body follows...
             S: a002 OK URLFETCH completed

      << Editors note: The submission server may LOGOUT>>

       S2: {to M} OK (2XX)

      Submission server returns OK to the MUA:
         S: 250 2.5.0 Ok.

    The messaging user agent, mail server and submit server MUST support
    IMAPv4 Rev1 [RFC3501], CATENATE [CATENATE] and URLAUTH [URLAUTH].

2.5.
     Additional Considerations

    The so-called "pawn-ticket" authorization mechanism uses a URI which
    contains its own authorization credentials using [URLAUTH].  The
    advantage of this mechanism is that the submit [RFC2476] server can
    not access any data on the [RFC3501] server without a "pawn-ticket"
    created by the client.  The "pawn-ticket" grants acces only to the
    specific data that the submit [RFC2476] server is authorized to
    access, can be revoked by the client, and can have a time-limited
    validity.

2.6.
     The fcc problem

    The "fcc problem" refers to a frequent need to deliver a copy of the
    message to a "file carbon copy" recipient.  By far, the most common
    case of fcc is a client leaving a copy of outgoing mail in a "sent
    messages" or "outbox" mailbox.

    In the traditional strategy, the MUA duplicates the effort spent in
    transmitting to the MSA by writing the message to the fcc destination
    in a separate step.  This may be a write to a local disk file or an
    APPEND to a mailbox on an IMAP server.  The latter is one of the
    "excessive and repetitive network data transmissions" which
    represents the "problem" aspect of the "fcc problem".

    The [CATENATE] extension to [RFC3501] addresses the fcc problem.  It
    requires making several simplifying assumptions:

Maes                    Expires - August 2005                [Page 8]


                           <Lemonade Profile>             February 2005

        (1a) there is one, and only one, fcc destination on a single
    server
        (2a) the server which holds the fcc is the same as the server
    which stages the outgoing message for submission
        (3a) it is desired that the fcc be a copy of the complete message
    text with all external data inserted in the message

    << Editors note: [POSTADDRESS] can be used to address issues (1a)
    and (2a). To be done later>>

3.
   Media Conversion

3.1.
     Introduction

    <<Editors note: To be done when agreed by WG>>

3.2.
     Static media conversion

    <<Editors note: To be done when agreed by WG>>

3.3.
     Conversion of streamed media

    <<Editors note: To be done when agreed by WG>>

3.4.
     Quick Reconnect scheme

    Mobile operators usually charge users for the time their mobile
    client gets connected to the Internet and/or for the amount of
    information sent/received. Thus a mobile client should minimize time
    it stays connected to its mail server, which suggests that it should
    disconnect and reconnect frequently.

    Also, it is possible that the mobile client unexpectedly leaves area
    of connectivity, which will require that the client reconnects when
    connectivity returns.

    << Editors note: Discussion about voluntarily versa non-voluntarily
    disconnects might go here>>

    IMAP can be verbose. Usually, in order to synchronize a client with a
    server after a disconnect, the client needs to issue at least the
    following commands: LOGIN/AUTHENTICATE, SELECT and several FETCH
    commands (see [IMAP-DISC] for more details).

    Thus, there is a desire to have a quick reconnect facility in IMAP,
    which will give a mobile client ability to resume a previously
    abandoned session, without the need to perform the full
    synchronization sequence as described above.

Maes                    Expires - August 2005                [Page 9]

                           <Lemonade Profile>             February 2005

    << Editors note: Example is as per reconnect-02, syntax is subject
    to change>>

       S: * OK [CAPABILITY IMAP4REV1 STARTTLS AUTH=LOGIN CONDSTORE
          X-DRAFT-W02-RECONNECT] imap.example.com IMAP4rev1 2001.315rh
          at Thu, 15 Jul 2004 11:47:49 -0400 (EDT)
       C: b0002 authenticate login (SID P1234567890 56789
    20010715194045000
       41,43:211,214:541)
       S: + VXNlciBOYW1lAA==
       C: dGVzdDg=
       S: + UGFzc3dvcmQA
       C: dGVzdDg=
       S: * FOLDER INBOX
       S: * 464 EXISTS
       S: * 3 RECENT
       S: * OK [UIDVALIDITY 3857529045] UIDVALIDITY
       S: * OK [UIDNEXT 550] Predicted next UID
       S: * OK [HIGHESTMODSEQ 20010715194045007]
       S: * 1 FETCH (UID 1 FLAGS (\Seen))
       S: b0002 OK [CAPABILITY IMAP4REV1 IDLE NAMESPACE MAILBOX-REFERRALS
    SCAN
       SORT THREAD=REFERENCES THREAD=ORDEREDSUBJECT MULTIAPPEND] User
       test8 authenticated

4.
   Future work

    Future versions of the Lemonade profile are expected to address
    issues related to access of email form mobile devices, possibly
    including:
       - transport optimization for low or costly bandwidth and less
         reliable mobile networks
       - server to client notifications outside of the traditional IMAP
         band
       - dealing with firewall and intermediaries
       - compression
       - filtering

Security Considerations

    Security considerations on the Lemonade Pull Model are discussed
   throughout section 2.

    << Editors note: TBD (Reconnect, etc.)>>

References

Maes                    Expires - August 2005               [Page 10]

                           <Lemonade Profile>             February 2005

    [IMAP-DISC] Melnikov, A.  "Synchronization Operations For
       Disconnected Imap4 Clients", IMAP-DISC, work in progress,  draft-
       melnikov-imap-disc-XX.txt

    [RFC2119] Brader, S.  "Keywords for use in RFCs to Indicate
       Requirement Levels", RFC 2119, March 1997.
       http://www.ietf.org/rfc/rfc2119

    [RFC2180] Gahrns, M.  "IMAP4 Multi-Accessed Mailbox Practice", RFC
       2180, July 1997.
       http://www.ietf.org/rfc/rfc2180

    [RFC2234] Crocker, D. and Overell, P.  "Augmented BNF for Syntax
       Specifications", RFC 2234, Nov 1997.
       http://www.ietf.org/rfc/rfc2234

    [RFC2683] Leiba, B. "IMAP4 Implementation Recommendations", RFC 2683
       Sep 1999.
       http://www.ietf.org/rfc/rfc2683

    [RFC2821]  Klensin, J., "Simple Mail Transfer Protocol", RFC 2821,
       April 2001.

    [RFC2822] Resnick, P. "Internet Message Format", RFC 2822, April
       2001.  http://www.ietf.org/rfc/rfc2822

    [RFC3501] Crispin, M. "IMAP4, Internet Message Access Protocol
       Version 4 rev1", RFC 3501, March 2003.
       http://www.ietf.org/rfc/rfc3501

    [RFC2476] Gellens, R. and Klensin, J., "Message Submission", RFC
       2476, December 1998.

    [CATENATE]Resnick, P., "Internet Message Access Protocol (IMAP)
       CATENATE Extension", draft-ietf-lemonade-catenate-XX, (work in
      progress).

    [BURL]    Newman, C., "Message Composition", draft-ietf-lemonade-
       burl-xx (work in progress).

    [URLAUTH] Crispin, M. and Newman, C., "Internet Message Access
       Protocol (IMAP) - URLAUTH Extension", draft-ietf-lemonade-urlauth-
       XX.txt, (work in progress).

    [POSTADDRESS] Melnikov, A., "IMAP4 POSTADDRESS extension", work in
       progress, draft-melnikov-imap-postaddress-XX.txt

Maes                    Expires - August 2005               [Page 11]

                           <Lemonade Profile>             February 2005

    [RECONNECT] Melnikov, A. and C. Wilson, " IMAP4 extension for quick
       reconnect ", work in progress, draft-ietf-lemonade-reconnect-
       XX.txt

Version History

    [1] We removed the sections of the profile related to mobile e-mail
       as well as discussion. This will be part of the next version of
       the Lemonade profile work.
    [2] We added detailed examples for the different steps included in
       section 2.4.
    [3] We added section 3 on media conversion
    [4] We added examples on Quick reconnect schemes in section 4.
    [5] We updated the security considerations
    [6] We fixed references based on updates above
    [7] We added a future work section
    [8] We fixed the boiler plate statements on the Ùstatus of this memo–
       and ÙCopriright–.

Acknowledgments

    This document is based on the work in progress described in draft-
    crispin-lemonade-pull-xx.txt.

Authors Addresses

    Stephane H. Maes
    Oracle Corporation
    500 Oracle Parkway
   M/S 4op634
    Redwood Shores, CA 94065
    USA
    Phone: +1-650-607-6296
    Email: [email-masked]

    Alexey Melnikov
    Isode Limited
    5 Castle Business Village
    36 Station Road
    Hampton, Middlesex
    TW12 2BX
    UK
    Email: [email-masked]

Intellectual Property Statement

    The IETF takes no position regarding the validity or scope of any
    intellectual property or other rights that might be claimed to
    pertain to the implementation or use of the technology described in

Maes                    Expires - August 2005               [Page 12]

                           <Lemonade Profile>             February 2005

    this document or the extent to which any license under such rights
    might or might not be available; neither does it represent that it
    has made any effort to identify any such rights.  Information on the
    IETF's procedures with respect to rights in standards-track and
    standards-related documentation can be found in BCP-11.  Copies of
    claims of rights made available for publication and any assurances of
    licenses to be made available, or the result of an attempt made to
    obtain a general license or permission for the use of such
    proprietary rights by implementors or users of this specification can
    be obtained from the IETF Secretariat.

    The IETF invites any interested party to bring to its attention any
    copyrights, patents or patent applications, or other proprietary
    rights which may cover technology that may be required to practice
    this standard.  Please address the information to the IETF Executive
    Director.

Acknowledgement

    Funding for the RFC Editor function is currently provided by the
    Internet Society.


Full Copyright Statement

    Copyright (C) The Internet Society 2004. This document is subject to
    the rights, licenses and restrictions contained in BCP 78, and except
    as set forth therein, the authors retain all their rights.

    This document and the information contained herein are provided on an
    "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
    OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
    ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
    INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
    INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
    WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

    This document and translations of it may be copied and furnished to
    others, and derivative works that comment on or otherwise explain it
    or assist in its implementation may be prepared, copied, published
    and distributed, in whole or in part, without restriction of any
    kind, provided that the above copyright notice and this paragraph are
    included on all such copies and derivative works.  However, this
    document itself may not be modified in any way, such as by removing
    the copyright notice or references to the Internet Society or other
    Internet organizations, except as needed for the purpose of
    developing Internet standards in which case the procedures for
    copyrights defined in the Internet Standards process must be

Maes                    Expires - August 2005               [Page 13]

                           <Lemonade Profile>             February 2005

    followed, or as required to translate it into languages other than
    English.

    The limited permissions granted above are perpetual and will not be
    revoked by the Internet Society or its successors or assigns.



Maes                    Expires - August 2005               [Page 14]

---

From: "Vaudreuil, Greg M (Greg)" <[email-masked]>
Date: Wed, 9 Mar 2005 12:52:19 -0600

GV1:- Future Delivery.  The diverse client can't send the message upon it's appointed time if it is in bad coverage, or otherwise doing something else interesting.  Needs server-side support as provided in draft-ietf-lemonade-futuredelivery.

GV2: Presumably, when the message is submitted, the mobile client has connectivity. If not, the message is not submitted and is presumably stored locally.  The role of the future-delivery enabled submission server is to make sure the message is actually injected into the mail system at the appointed time, even if the client is on an airplane, out-of-battery, on a cruise vacation, or otherwise without digital coverage at that time.

GV:1 - Message context.  The clients need to present the proper icon's, message counts, and/or views based on the historical context of the message without downloading the entire message header for each message in a mailbox.  To do this, the LMTP deposit process is expected to set a new IMAP flag to indicate the message context.  The client has ready access to flags and can use them for local processing without downloading all the message headers.

GV2: Current user interfaces for unified messaging systems use colors, icons, or other means to visually distinguish between voicemail, fax, MMS, and email messages in a lengthy mailbox listing.  Each of these messages context's can/should be indicated by a message-context RFC2822 header.  Unfortunately for a limited-connectivity device, IMAP does not provide an easy way to get that header information without retrieving the full headers of all messages.  By copying that information into an IMAP flag at deposit time, the information is available by a much cheaper mechanism.  (recall I had an Internet draft on this topic, draft-ietf-lemonade-msg-context-00.txt, and the consensus was that it was unnecessary and could be adequately covered in the profile since no new protocol was defined)

I now understand the other two items I mentioned are for a later phase.

Greg V.

---

From: Randall Gellens <[email-masked]>
Date: Thu, 10 Mar 2005 05:09:40 -0800

I'm resending this to make it easier to read.

Here are my comments.  See lines starting with "]]]".

Lemonade                                                                

                             Lemonade Profile 
    
Status of this Memo 

    

    
Abstract 
    
   This document describes the Lemonade profile to allow clients to 
   submit new email messages incorporating content which resides on 
   locations external to the client ("forward without download").  
]]] ...describes a profile (a set of required extensions, restrictions,
]]] and usage modes) of mail protocols such as IMAP and Submission.
]]] This profile allows clients (especially those that are constrained
]]] in memory, bandwidth, processing power, or other areas) to
]]] effeciently 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 have media attached to a
]]] message converted if required, and to more efficiently maintain
]]] a synchronized cache of received messages.
    
]]]                                               ^^^^^ -> "various"
 
   In addition, the Lemonade profile contains Lemonade Command 
   extensions for quick reconnect and media conversion. 
]]] No, these must not be in a profile document, they must be in
]]] their own documents and referenced here.

 



Table of Contents 

1. 
   Introduction 



      - Quick reconnect   

2. 
  Forward without download 
    
2.1. 
    Motivations 
    
]]]       ^^^^^^^^^^^^^^^^^^^^^^^^ <<delete>>
]]] ^^^^^^^^^ <<delete>>
   high-latency links. 

   Pull has the distinct advantage of maintaining one submission 
]]]^^^^ -> "This approach"
]]]             ^^^^^^^^ <<<delete 'distinct'>>>
   protocol, and thus avoids the risk of having multiple parallel and 
   possible divergent mechanisms for submission.  Furthermore, by 
   keeping the details of message submission in the SUBMIT server, the 
   Lemonade Pull Model can work with other message retrieval protocols 
   such as POP, NNTP, or whatever else may be designed in the future. 
    
2.2. 
    Message Sending Overview 

]]]                                                     ^^^^^^^^^^^^^^
]]] (What is a "time-consuming message"?)



2.3. 
    Traditional Strategy 

    

    

    

    

    

2.4. 
    Step by step description 

 



    

     Example: 



      

 



     M: A0054 GENURLAUTH 

      



      
      S2: {to M} OK (2XX) 

 
2.5. 

2.6. 
    The fcc problem 

    



    
3. 
  Media Conversion 
    
3.1. 
    Introduction 

3.2. 
    Static media conversion 

3.3. 

3.4. 
    Quick Reconnect scheme 

    

    

 
4. 
  Future work 

Security Considerations 

    
References 

    

    

    

    

    

 

    
Version History 

Acknowledgments 

Authors Addresses 
    
   Stephane H. Maes 
   Oracle Corporation 
   500 Oracle Parkway 
   M/S 4op634 
   Redwood Shores, CA 94065 
   USA 
   Phone: +1-650-607-6296 
    
   Alexey Melnikov 
   Isode Limited 

            
    
Acknowledgement 

    
Full Copyright Statement