[Docs] [txt|pdf|xml|html] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-karp-morg-sortdisplay) 00 01 02 03 RFC 5957

Message Organization Working Group                               D. Karp
Internet-Draft                                                    Zimbra
Updates: 5256 (if approved)                             January 30, 2009
Intended status: Standards Track
Expires: August 3, 2009


       Display-based Address Sorting for the IMAP4 SORT Extension
                     draft-ietf-morg-sortdisplay-00

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.

   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.

   This Internet-Draft will expire on August 3, 2009.

Copyright Notice

   Copyright (c) 2009 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.

Abstract

   This document describes an IMAP protocol extension enabling server-



Karp                     Expires August 3, 2009                 [Page 1]

Internet-Draft     IMAP4 Display-based Address Sorting      January 2009


   side message sorting based on the commonly-displayed portion of the
   From header.


Table of Contents

   1.  Conventions Used in This Document . . . . . . . . . . . . . . . 3
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . 3
   3.  The DISPLAYFROM Sort Key  . . . . . . . . . . . . . . . . . . . 3
   4.  Formal Syntax . . . . . . . . . . . . . . . . . . . . . . . . . 4
   5.  Security Considerations . . . . . . . . . . . . . . . . . . . . 4
   6.  Internationalization Considerations . . . . . . . . . . . . . . 4
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4
   8.  Normative References  . . . . . . . . . . . . . . . . . . . . . 4
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . . . 5




































Karp                     Expires August 3, 2009                 [Page 2]

Internet-Draft     IMAP4 Display-based Address Sorting      January 2009


1.  Conventions Used in This Document

   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].


2.  Introduction

   The [SORT] extension to the [IMAP] protocol provides a means for
   server-based sorting of messages.  It defines a set of sort criteria
   and the mechanism for determining the sort value of a message for
   each such ordering.

   The [SORT] extension's FROM ordering sorts messages lexically on the
   [IMAP] addr-part of the first address in the From header.  This
   document provides an alternate ordering, DISPLAYFROM, which sorts
   messages lexically based on the From address's [RFC2822] display-
   name, when present.

   A server that supports the DISPLAYFROM sort criterion indicates this
   by returning "SORT=DISPLAYFROM" in its CAPABILITY response.


3.  The DISPLAYFROM Sort Key

   This document introduces a new [SORT] sort-key, DISPLAYFROM.

   A message's sort value under the DISPLAYFROM ordering MUST be derived
   from the first [RFC2822] mailbox in its From header as follows:

   o  If the From header is absent or if the header contains no
      mailboxes, the message's sort value is the empty string.

   o  If the mailbox contains an [RFC2822] display-name, replace each
      instance of [RFC2822] CFWS in the display-name with a single
      space, trim all leading and trailing whitespace, and decode any
      [RFC2047] encoded-words.  If the resulting string is not the empty
      string, use it as the sort value for the message.

   o  Otherwise, completely remove all [RFC2822] CFWS from the mailbox's
      [RFC2822] addr-spec and use the resulting string as the message's
      sort value.








Karp                     Expires August 3, 2009                 [Page 3]

Internet-Draft     IMAP4 Display-based Address Sorting      January 2009


4.  Formal Syntax

   The following syntax specification uses the Augmented Backus-Naur
   Form (ABNF) notation as specified in [RFC4234].  [IMAP] defines the
   non-terminal "capability" and [SORT] defines "sort-key".

capability    =/ "SORT=DISPLAYFROM"

sort-key      =/ "DISPLAYFROM"


5.  Security Considerations

   This document defines an additional IMAP4 capability.  As such, it
   does not change the underlying security considerations of [IMAP].
   The author believes that no new security issues are introduced with
   this additional IMAP4 capability.


6.  Internationalization Considerations

   DISPLAYFROM is a string-based sort criterion.  As stated in [SORT],
   the collations mandated by I18NLEVEL=1 or I18NLEVEL=2 from [RFC5255]
   MUST be followed when sorting such strings.

   The DISPLAYFROM ordering sorts on the full decoded [RFC2822] display-
   name, when present.  It does not attempt to parse this string in a
   locale- or language-dependent manner in order to determine and sort
   on some semantically meaningful substring such as the surname.


7.  IANA Considerations

   [IMAP] capabilities are registered by publishing a standards track or
   IESG-approved experimental RFC.  This document constitutes
   registration of the SORT=DISPLAYFROM capability in the [IMAP]
   capabilities registry.


8.  Normative References

   [IMAP]     Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION
              4rev1", RFC 3501, March 2003.

   [RFC2047]  Moore, K., "MIME (Multipurpose Internet Mail Extensions)
              Part Three: Message Header Extensions for Non-ASCII Text",
              RFC 2047, November 1996.




Karp                     Expires August 3, 2009                 [Page 4]

Internet-Draft     IMAP4 Display-based Address Sorting      January 2009


   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2822]  Resnick, P., "Internet Message Format", RFC 2822,
              April 2001.

   [RFC4234]  Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
              Specifications: ABNF", RFC 4234, October 2005.

   [RFC5255]  Newman, C., Gulbrandsen, A., and A. Melnikov, "Internet
              Message Access Protocol Internationalization", RFC 5255,
              June 2008.

   [SORT]     Crispin, M. and K. Murchison, "Internet Message Access
              Protocol - SORT and THREAD Extensions", RFC 5256,
              June 2008.


Author's Address

   Dan Karp
   Zimbra, a Yahoo! Company
   701 First St.
   Sunnyvale, CA  94089
   USA

   Email: dkarp@zimbra.com
   URI:   http://www.zimbra.com























Karp                     Expires August 3, 2009                 [Page 5]


Html markup produced by rfcmarkup 1.109, available from https://tools.ietf.org/tools/rfcmarkup/