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

Versions: (draft-saintandre-sieve-notify-xmpp) 00 01 02 03 04 05 06 07 08 09 RFC 5437

Sieve Working Group                                       P. Saint-Andre
Internet-Draft                                 XMPP Standards Foundation
Intended status: Standards Track                             A. Melnikov
Expires: August 22, 2008                                   Isode Limited
                                                       February 19, 2008


                   Sieve Notification Mechanism: xmpp
                    draft-ietf-sieve-notify-xmpp-09

Status of this Memo

   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 becomes
   aware will be disclosed, in accordance with Section 6 of 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 22, 2008.

Copyright Notice

   Copyright (C) The IETF Trust (2008).

Abstract

   This document describes a profile of the Sieve extension for
   notifications, to allow notifications to be sent over the Extensible
   Messaging and Presence Protocol (XMPP), also known as Jabber.







Saint-Andre & Melnikov   Expires August 22, 2008                [Page 1]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Overview . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  3
   2.  Definition . . . . . . . . . . . . . . . . . . . . . . . . . .  3
     2.1.  Notify parameter "method"  . . . . . . . . . . . . . . . .  3
     2.2.  Test notify_method_capability  . . . . . . . . . . . . . .  3
     2.3.  Notify tag ":from" . . . . . . . . . . . . . . . . . . . .  4
     2.4.  Notify tag ":importance" . . . . . . . . . . . . . . . . .  4
     2.5.  Notify tag ":message"  . . . . . . . . . . . . . . . . . .  4
     2.6.  Notify tag ":options"  . . . . . . . . . . . . . . . . . .  4
     2.7.  XMPP syntax  . . . . . . . . . . . . . . . . . . . . . . .  4
   3.  Examples . . . . . . . . . . . . . . . . . . . . . . . . . . .  5
     3.1.  Basic action . . . . . . . . . . . . . . . . . . . . . . .  6
     3.2.  Action with body . . . . . . . . . . . . . . . . . . . . .  6
     3.3.  Action with body, importance, message, and subject . . . .  7
     3.4.  Action with from, message, importance, body, and
           subject  . . . . . . . . . . . . . . . . . . . . . . . . .  8
   4.  Requirements Conformance . . . . . . . . . . . . . . . . . . .  9
   5.  Internationalization Considerations  . . . . . . . . . . . . . 10
   6.  Security Considerations  . . . . . . . . . . . . . . . . . . . 11
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 11
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 12
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 12
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 13
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 14
   Intellectual Property and Copyright Statements . . . . . . . . . . 15























Saint-Andre & Melnikov   Expires August 22, 2008                [Page 2]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


1.  Introduction

1.1.  Overview

   The [NOTIFY] extension to the [SIEVE] mail filtering language is a
   framework for providing notifications by employing URIs to specify
   the notification mechanism.  This document defines how xmpp URIs (see
   [XMPP-URI]) are used to generate notifications via the Extensible
   Messaging and Presence Protocol [XMPP], which is widely implemented
   in Jabber instant messaging technologies.

1.2.  Terminology

   This document inherits terminology from [NOTIFY], [SIEVE], and
   [XMPP].

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


2.  Definition

2.1.  Notify parameter "method"

   The "method" parameter MUST be a URI that conforms to the xmpp URI
   scheme (as specified in [XMPP-URI]) and that identifies an XMPP
   account associated with the email inbox.  The URI MAY include the
   resource identifier of an XMPP address and/or the query component
   portion of an XMPP URI, but SHOULD NOT include an authority component
   or fragment identifier component.  The processing application MUST
   extract an XMPP address from the URI in accordance with the
   processing rules specified in [XMPP-URI].  The resulting XMPP address
   MUST be encapsulated in XMPP syntax as the value of the XMPP 'to'
   attribute.

2.2.  Test notify_method_capability

   In response to a notify_method_capability test for the "online"
   notification-capability, an implementation SHOULD return a value of
   "yes" if it has knowledge of an active presence session (see
   [XMPP-IM]) for the specified XMPP notification-uri; otherwise it
   SHOULD return a value of "maybe" (since typical XMPP systems may not
   allow a Sieve engine to gain knowledge about the presence of XMPP
   entities).





Saint-Andre & Melnikov   Expires August 22, 2008                [Page 3]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


2.3.  Notify tag ":from"

   If included, the ":from" tag MUST be an electronic address that
   conforms to the "Mailbox" rule defined in [RFC2821].  The value of
   the ":from" tag MAY be included in the human-readable XML character
   data of the XMPP notification; alternatively or in addition, it MAY
   be transformed into formal XMPP syntax, in which case it MUST be
   encapsulated as the value of an XMPP Stanza Headers and Internet
   Metadata [SHIM] header named "Resent-From".

2.4.  Notify tag ":importance"

   The ":importance" tag has no special meaning for this notification
   mechanism, and this specification puts no restriction on its use.
   The value of the ":importance" tag MAY be transformed into XMPP
   syntax (in addition to or instead of including appropriate text in
   the XML character data of the XMPP <body/> element); if so, it SHOULD
   be encapsulated as the value of an XMPP Stanza Headers and Internet
   Metadata [SHIM] header named "Urgency", where the XML character of
   that header is "high" if the value of the ":importance" tag is "1",
   "medium" if the value of the ":importance" tag is "2", and "low" if
   the value of the ":importance" tag is "3".

2.5.  Notify tag ":message"

   If the ":message" tag is included, that string MUST be transformed
   into the XML character data of an XMPP <body/> element (where the
   string is generated according to the guidelines specified in Section
   3.6 of [NOTIFY]).

2.6.  Notify tag ":options"

   The ":options" tag has no special meaning for this notification
   mechanism.  Any handling of this tag is the responsibility of an
   implementation.

2.7.  XMPP syntax

   The xmpp mechanism results in the sending of an XMPP message to
   notify a recipient about an email message.  The general XMPP syntax
   is as follows:

   o  The notification MUST be an XMPP <message/> stanza.
   o  The value of the XMPP 'from' attribute SHOULD be the XMPP address
      of the notification service associated with the Sieve engine or
      the XMPP address of the entity to be notified.  The value of the
      XMPP 'from' attribute MUST NOT be generated from the Sieve ":from"
      tag.



Saint-Andre & Melnikov   Expires August 22, 2008                [Page 4]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


   o  The value of the XMPP 'to' attribute MUST be the XMPP address
      specified in the XMPP URI contained in the "method" notify
      parameter.
   o  The value of the XMPP 'type' attribute MUST be 'headline' or
      'normal'.
   o  The XMPP <message/> stanza MUST include a <body/> child element.
      If the ":message" tag is included in the Sieve script, that string
      MUST be used as the XML character data of the <body/> element.  If
      not and if the XMPP URI contained in the "method" notify parameter
      specified a "body" parameter in the query component, that value
      SHOULD be used.  Otherwise the XML character data SHOULD be some
      configurable text indicating that the message is a Sieve
      notification.
   o  The XMPP <message/> stanza MAY include a <subject/> child element.
      If the XMPP URI contained in the "method" notify parameter
      specified a "subject" parameter in the query component, that value
      SHOULD be used as the XML character data of the <subject/>
      element.  Otherwise the XML character data SHOULD be some
      configurable text indicating that the message is a Sieve
      notification.
   o  The XMPP <message/> stanza SHOULD include a URI for the recipient
      to use as a hint in locating the message, encapsulated as the XML
      character data of a <url/> child element of an <x/> element
      qualified by the 'jabber:x:oob' namespace as specified in [OOB].
      If included, the URI SHOULD be an Internet Message Access Protocol
      [IMAP] URL that specifies the location of the message as defined
      in [IMAP-URL], but MAY be another URI type that can specify or
      hint at the location of an email message, such as a URI for an
      HTTP resource [HTTP] or a POP3 mailbox [POP-URL] at which the
      message can be accessed.  It is not expected that an XMPP user
      agent shall directly handle such a URI, but instead that it shall
      invoke an appropriate helper application to handle the URI.
   o  The XMPP <message/> stanza MAY include an XMPP Stanza Headers and
      Internet Metadata [SHIM] header named "Resent-From".  If the Sieve
      script included a ":from" tag, the "Resent-From" value MUST be the
      value of the ":from" tag; otherwise the "Resent-From" value SHOULD
      be the envelope recipient address of the original email message
      that triggered the notification.


3.  Examples

   In the following examples, the sender of the email has an address of
   <mailto:juliet@example.org>, the entity to be notified has an email
   address of <mailto:romeo@example.com> and an XMPP address of
   romeo@im.example.com (resulting in an XMPP URI of
   <xmpp:romeo@im.example.com>), and the notification service associated
   with the Sieve engine has an XMPP address of notify.example.com.



Saint-Andre & Melnikov   Expires August 22, 2008                [Page 5]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


   Note: In the following examples, line breaks are included in XMPP
   URIs solely for the purpose of readability.

3.1.  Basic action

   The following is a basic Sieve notify action with only a method.  The
   XML character data of the XMPP <body/> and <subject/> elements are
   therefore generated by the Sieve engine based on configuration.  In
   addition, the Sieve engine includes a URI pointing to the message.

   Basic action (Sieve syntax)

     notify "xmpp:romeo@im.example.com"

   The resulting XMPP <message/> stanza might be as follows.

   Basic action (XMPP syntax)

     <message from='notify.example.com'
              to='romeo@im.example.com'
              type='headline'
              xml:lang='en'>
       <subject>SIEVE</subject>
       <body>&lt;juliet@example.com&gt; You got mail.</body>
       <x xmlns='jabber:x:oob'>
         <url>
           imap://romeo@example.com/INBOX;UIDVALIDITY=385759043/;UID=18
         </url>
       </x>
     </message>

3.2.  Action with body

   The following action contains a "body" parameter in the query
   component of the XMPP URI but no ":message" tag in the Sieve script.
   As a result, the XML character data of the XMPP <body/> element in
   the XMPP notification is taken from the XMPP URI.  In addition, the
   Sieve engine includes a URI pointing to the message.

   Action with body (Sieve syntax)

     notify "xmpp:romeo@im.example.com?message
              ;body=Wherefore%20art%20thou%3F"

   The resulting XMPP <message/> stanza might be as follows.






Saint-Andre & Melnikov   Expires August 22, 2008                [Page 6]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


   Action with body (XMPP syntax)

     <message from='notify.example.com'
              to='romeo@im.example.com'
              type='headline'
              xml:lang='en'>
       <subject>SIEVE</subject>
       <body>Wherefore art thou?</body>
       <x xmlns='jabber:x:oob'>
         <url>
           imap://romeo@example.com/INBOX;UIDVALIDITY=385759044/;UID=19
         </url>
       </x>
     </message>

3.3.  Action with body, importance, message, and subject

   The following action specifies an ":importance" tag and a ":message"
   tag in the Sieve script, as well as a "body" parameter and a
   "subject" parameter in the query component of the XMPP URI.  As a
   result, the ":message" tag from the Sieve script overrides the "body"
   parameter from the XMPP URI when generating the XML character data of
   the XMPP <body/> element.  In addition, the Sieve engine includes a
   URI pointing to the message.

   Action with body, importance, message, and subject (Sieve syntax)

     notify :importance "1"
            :message "Contact Juliet immediately!"
            "xmpp:romeo@im.example.com?message
              ;body=You%27re%20in%20trouble
              ;subject=ALERT%21"

   The resulting XMPP <message/> stanza might be as follows.

















Saint-Andre & Melnikov   Expires August 22, 2008                [Page 7]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


   Action with body, importance, message, and subject (XMPP syntax)

     <message from='notify.example.com'
              to='romeo@im.example.com'
              type='headline'
              xml:lang='en'>
       <subject>ALERT!</subject>
       <body>Contact Juliet immediately!</body>
       <headers xmlns='http://jabber.org/protocol/shim'>
         <header name='Urgency'>high</header>
       </headers>
       <x xmlns='jabber:x:oob'>
         <url>
           imap://romeo@example.com/INBOX;UIDVALIDITY=385759045/;UID=20
         </url>
       </x>
     </message>

3.4.  Action with from, message, importance, body, and subject

   The following action specifies a ":from" tag, an ":importance" tag,
   and a ":message" tag in the Sieve script, as well as a "body"
   parameter and a "subject" parameter in the query component of the
   XMPP URI.  As a result, the ":message" tag from the Sieve script
   overrides the "body" parameter from the XMPP URI when generating the
   XML character data of the XMPP <body/> element.  In addition, the
   Sieve engine includes a URI pointing to the message, as well as an
   XMPP Stanza Headers and Internet Metadata [SHIM] header named
   "Resent-From" (which encapsulates the value of the ":from" tag).

   Action with body, from, importance, message, and subject (Sieve
   syntax)

     notify :from "romeo.my.romeo@example.com"
            :importance "1"
            :message "Contact Juliet immediately!"
            "xmpp:romeo@im.example.com?message
              ;body=You%27re%20in%20trouble
              ;subject=ALERT%21"

   The resulting XMPP <message/> stanza might be as follows.










Saint-Andre & Melnikov   Expires August 22, 2008                [Page 8]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


   Action with body, from, importance, message, and subject (XMPP
   syntax)

     <message from='notify.example.com'
              to='romeo@im.example.com'
              type='headline'
              xml:lang='en'>
       <subject>ALERT!</subject>
       <body>Contact Juliet immediately!</body>
       <headers xmlns='http://jabber.org/protocol/shim'>
         <header name='Resent-From'>romeo.my.romeo@example.com</header>
         <header name='Urgency'>high</header>
       </headers>
       <x xmlns='jabber:x:oob'>
         <url>
           imap://romeo@example.com/INBOX;UIDVALIDITY=385759045/;UID=21
         </url>
       </x>
     </message>


4.  Requirements Conformance

   Section 3.8 of [NOTIFY] specifies a set of requirements for Sieve
   notification methods.  The conformance of the xmpp notification
   mechanism is provided here.

   1.   An implementation of the xmpp notification method SHOULD NOT
        modify the final notification text (e.g., to limit the length);
        however, a given deployment MAY do so (e.g., if recipients pay
        per character or byte for XMPP messages).  Modification of
        characters themselves should not be necessary, since XMPP
        character data is encoded in [UTF-8].
   2.   An implementation MAY ignore parameters specified in the
        ":from", ":importance", and ":options" tags.
   3.   There is no recommended default message for an implementation to
        include if the ":message" argument is not specified.
   4.   A notification sent via the xmpp notification method MAY include
        a timestamp in the textual message.
   5.   The value of the XMPP 'from' attribute MUST be the XMPP address
        of the notification service associated with the Sieve engine.
        The value of the Sieve ":from" tag MAY be transformed into the
        value of an XMPP Stanza Headers and Internet Metadata [SHIM]
        header named "Reply-To".
   6.   The value of the XMPP 'to' attribute MUST be the XMPP address
        specified in the XMPP URI contained in the "method" parameter.





Saint-Andre & Melnikov   Expires August 22, 2008                [Page 9]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


   7.   In accordance with [XMPP-URI], an implementation MUST ignore any
        URI action or parameter it does not understand (i.e., the URI
        MUST be processed as if the action or parameter were not
        present).  It is RECOMMENDED to support the XMPP "message" query
        type (see [QUERIES]) and the associated "body" and "subject"
        parameters, which parameters SHOULD be mapped to the XMPP
        <body/> and <subject/> child elements of the XMPP <message/>
        stanza, respectively.  However, if included then the Sieve
        notify ":message" parameter MUST be mapped to the XMPP <body/>
        element, overriding the "body" parameter (if any) included in
        the XMPP URI.
   8.   An implementation MUST NOT include any other extraneous
        information not specified in parameters to the notify action.
   9.   In response to a notify_method_capability test for the "online"
        notification-capability, an implementation SHOULD return a value
        of "yes" if it has knowledge of an active presence session (see
        [XMPP-IM]) for the specified XMPP notification-uri but only if
        the entity that requested the test is authorized to know the
        presence of the associated XMPP entity (e.g., via explicit
        presence subscription as specified in [XMPP-IM]); otherwise it
        SHOULD return a value of "maybe" (since typical XMPP systems may
        not allow a Sieve engine to gain knowledge about the presence of
        XMPP entities).
   10.  An implementation SHOULD NOT attempt to retry delivery of a
        notification if it receives an XMPP error of type "auth" or
        "cancel", MAY attempt to retry delivery if it receives an XMPP
        error of type "wait", and MAY attempt to retry delivery if it
        receives an XMPP error of "modify" but only if it makes
        appropriate modifications to the notification (see [XMPP]); in
        any case the number of retries SHOULD be limited to a
        configurable number no less than 3 and no more than 10.  An
        implementation MAY throttle notifications if the number of
        notifications within a given time period becomes excessive
        according to local service policy.  Duplicate suppression (if
        any) is a matter of implementation and is not specified herein.


5.  Internationalization Considerations

   Although an XMPP address may contain nearly any [UNICODE] character,
   the value of the "method" parameter MUST be a Uniform Resource
   Identifier (see [URI]) rather than an Internationalized Resource
   Identifier (see [IRI]).  The rules specified in [XMPP-URI] MUST be
   followed when generating XMPP URIs.

   In accordance with Section 13 of RFC 3920, all data sent over XMPP
   MUST be encoded in [UTF-8].




Saint-Andre & Melnikov   Expires August 22, 2008               [Page 10]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


6.  Security Considerations

   Depending on the information included, sending a notification can be
   comparable to forwarding mail to the notification recipient.  Care
   must be taken when forwarding mail automatically, to ensure that
   confidential information is not sent into an insecure environment.
   In particular, implementations MUST conform to the security
   considerations given in [NOTIFY], [SIEVE], and [XMPP].

   [NOTIFY] specifies that a notification method MUST provide mechanisms
   for avoiding notification loops.  One type of notification loop can
   be caused by message forwarding; however, such loops are prevented
   because XMPP does not support forwarding of messages from one XMPP
   address to another.  Another type of notification loop can be caused
   by auto-replies to XMPP messages received by the XMPP notification
   service associated with the Sieve engine; therefore such a service
   MUST NOT auto-reply to XMPP messages it receives.

   A common use case might be for a user to create a script that enables
   the Sieve engine to act differently if the user is currently
   available at a particular type of service (e.g., send notifications
   to the user's XMPP address if the user has an active session at an
   XMPP service).  Whether the user is currently available can be
   determined by means of a notify_method_capability test for the
   "online" notification-capability.  In XMPP, information about current
   network availability is called "presence" (see also [MODEL]).  Since
   [XMPP-IM] requires that a user must approve a presence subscription
   before an entity can gain access to the user's presence information,
   a limited but reasonably safe implementation might be for the Sieve
   engine to request a subscription to the user's presence.  The user
   would then need to approve that subscription request so that the
   Sieve engine can act appropriately depending on whether the user is
   online or offline.  However, the Sieve engine MUST NOT use the user's
   presence information when processing scripts on behalf of a script
   owner other than the user, unless the Sieve engine has explicit
   knowledge (e.g., via integration with an XMPP server's presence
   authorization rules) that the script owner is authorized to know the
   user's presence.  While it would be possible to design a more
   advanced approach to delegation of presence authorization, any such
   approach is left to future standards work.


7.  IANA Considerations

   The following template provides the IANA registration of the Sieve
   notification mechanism specified in this document:





Saint-Andre & Melnikov   Expires August 22, 2008               [Page 11]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


     To: iana@iana.org
     Subject: Registration of new Sieve notification mechanism
     Mechanism name: xmpp
     Mechanism URI: draft-saintandre-rfc4622bis
     Mechanism-specific options: none
     Standards Track/IESG-approved experimental RFC number: this RFC
     Person and email address to contact for further information:
          Peter Saint-Andre <stpeter@jabber.org>

   This information should be added to the list of Sieve notification
   mechanisms maintained at
   <http://www.iana.org/assignments/sieve-notification>.


8.  References

8.1.  Normative References

   [NOTIFY]   Melnikov, A., Leiba, B., Segmuller, W., and T. Martin,
              "Sieve Email Filtering: Notifications",
              draft-ietf-sieve-notify-12 (work in progress),
              December 2007.

   [OOB]      Saint-Andre, P., "Out of Band Data", XSF XEP 0066,
              August 2006.

   [QUERIES]  Saint-Andre, P., "XMPP URI Scheme Query Components", XSF
              XEP 0147, September 2006.

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

   [SHIM]     Saint-Andre, P. and J. Hildebrand, "Stanza Headers and
              Internet Metadata", XSF XEP 0131, July 2006.

   [SIEVE]    Showalter, T. and P. Guenther, "Sieve: An Email Filtering
              Language", draft-ietf-sieve-3028bis-13 (work in progress),
              October 2007.

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

   [XMPP-URI]
              Saint-Andre, P., "Internationalized Resource Identifiers
              (IRIs) and Uniform Resource Identifiers (URIs) for the
              Extensible Messaging and Presence Protocol (XMPP)",
              draft-saintandre-rfc4622bis-01 (work in progress),
              June 2007.



Saint-Andre & Melnikov   Expires August 22, 2008               [Page 12]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


8.2.  Informative References

   [HTTP]     Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
              Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
              Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.

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

   [IMAP-URL]
              Melnikov, A. and C. Newman, "IMAP URL Scheme", RFC 5092,
              November 2007.

   [MODEL]    Day, M., Rosenberg, J., and H. Sugano, "A Model for
              Presence and Instant Messaging", RFC 2778, February 2000.

   [POP-URL]  Gellens, R., "POP URL Scheme", RFC 2384, August 1998.

   [IRI]      Duerst, M. and M. Suignard, "Internationalized Resource
              Identifiers (IRIs)", RFC 3987, January 2005.

   [UNICODE]  The Unicode Consortium, "The Unicode Standard, Version
              3.2.0", 2000.

              The Unicode Standard, Version 3.2.0 is defined by The
              Unicode Standard, Version 3.0 (Reading, MA, Addison-
              Wesley, 2000.  ISBN 0-201-61633-5), as amended by the
              Unicode Standard Annex #27: Unicode 3.1
              (http://www.unicode.org/reports/tr27/) and by the Unicode
              Standard Annex #28: Unicode 3.2
              (http://www.unicode.org/reports/tr28/).

   [URI]      Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
              Resource Identifier (URI): Generic Syntax", STD 66,
              RFC 3986, January 2005.

   [UTF-8]    Yergeau, F., "UTF-8, a transformation format of ISO
              10646", STD 63, RFC 3629, November 2003.

   [XMPP]     Saint-Andre, P., "Extensible Messaging and Presence
              Protocol (XMPP): Core", RFC 3920, October 2004.

   [XMPP-IM]  Saint-Andre, P., "Extensible Messaging and Presence
              Protocol (XMPP): Instant Messaging and Presence",
              RFC 3921, October 2004.






Saint-Andre & Melnikov   Expires August 22, 2008               [Page 13]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


Authors' Addresses

   Peter Saint-Andre
   XMPP Standards Foundation

   Email: stpeter@jabber.org
   URI:   https://stpeter.im/


   Alexey Melnikov
   Isode Limited

   Email: Alexey.Melnikov@isode.com






































Saint-Andre & Melnikov   Expires August 22, 2008               [Page 14]

Internet-Draft          Sieve Notify Method: xmpp          February 2008


Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

   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, THE IETF TRUST 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.


Intellectual Property

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat 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 implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.


Acknowledgment

   Funding for the RFC Editor function is provided by the IETF
   Administrative Support Activity (IASA).





Saint-Andre & Melnikov   Expires August 22, 2008               [Page 15]


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