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

Versions: (draft-martin-sieve-notify) 00 01 02 03 04 05 06 07 08 09 10 11 12 RFC 5435

Sieve Working Group                                     A. Melnikov, Ed.
Internet-Draft                                             Isode Limited
Intended status: Standards Track                           B. Leiba, Ed.
Expires: August 4, 2007                                     W. Segmuller
                                         IBM T.J. Watson Research Center
                                                               T. Martin
                                                    BeThereBeSquare Inc.
                                                        January 31, 2007


                     Sieve Extension: Notifications
                       draft-ietf-sieve-notify-06

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 4, 2007.

Copyright Notice

   Copyright (C) The IETF Trust (2007).

Abstract

   Users go to great lengths to be notified as quickly as possible that
   they have received new mail.  Most of these methods involve polling
   to check for new messages periodically.  A push method handled by the
   final delivery agent gives users quicker notifications and saves



Melnikov, et al.         Expires August 4, 2007                 [Page 1]


Internet-Draft       Sieve Extension: Notifications         January 2007


   server resources.  This document does not specify the notification
   method but it is expected that using existing instant messaging
   infrastructure such as XMPP, or SMS messages will be popular.  This
   draft describes an extension to the Sieve mail filtering language
   that allows users to give specific rules for how and when
   notifications should be sent.

Changes since draft-ietf-sieve-notify-05

   o  Fixed XMPP URI in one example.

   o  Addressed Michael's issue with how timestamp are described.

   o  Renamed "valid_notif_method" to "valid_notify_method".

   o  Added text about truncation of a textual part when it is stored in
      a variable using extract_text.

   o  Changed tagged :method argument to positional argument.

   o  Added text about notification throttling, identifying notification
      source and restricting values of the :from parameter.

   o  Added a requirement on documents describing notification methods
      to list which URI parameters must be ignored.

Changes since draft-ietf-sieve-notify-04

   o  Made notification method required.

   o  Defined "mailto" as a mandatory-to-implement method.

   o  Added normative reference to mailto.

   o  Clarified that :importance may be treated as a transport
      indicator.

   o  Clarified that :importance value can be included in the default
      :message, if one is not specified.

   o  Made the default :message implementation specific.

   o  Renamed the capability name from "notify" to "enotify"

   o  Updated IANA registration.

   o  Moved text about ManageSieve capability to the ManageSieve
      document itself.



Melnikov, et al.         Expires August 4, 2007                 [Page 2]


Internet-Draft       Sieve Extension: Notifications         January 2007


   o  Removed reference to IANA registry for options.

   o  Some miscellaneous text cleanup and clarification.

Changes since draft-ietf-sieve-notify-03

   o  Added a warning that "notify" must not be used as a crappy form of
      "redirect".

   o  Added a warning about using "notify" to forward confidential
      information in order to bypass organization's policy.

   o  Fixed syntax of the :options argument - it is a string list, each
      string containing "<attribute>=<value>"

   o  Renamed :priority to :importance

   o  Cleaned up section about requirements on methods.

Changes since draft-ietf-sieve-notify-02

   o  Added :from tagged argument.

   o  Added Extract_text action, which allows to extract content of the
      first text/* part.

   o  Added back the ":options" parameter to the notify action.

   o  Added new section talking about requirements on notification
      method specs.

   o  Added more examples.

Changes since draft-ietf-sieve-notify-00

   o  Updated references, etc.

   o  Added IANA considerations section.

   o  Removed denotify action.

   o  Updated examples to use the variables extension.

   o  Replaced notification method with URI.

   o  Removed text suggesting that this extension can be used to track
      all Sieve actions taken.




Melnikov, et al.         Expires August 4, 2007                 [Page 3]


Internet-Draft       Sieve Extension: Notifications         January 2007


   o  Changed priority to be a string.

   o  Added text about URI verification.

   o  Clarified that a notification method is allowed to perform
      adaptation of notification context (e.g. truncation, charset
      conversion, etc.).  These adaptations must be documented in a
      document describing the notification method.

   o  Clarified that notify is compatible with all existing actions.

   o  Removed the :id parameter to the notify action.

   o  Added valid_notif_method test that allows to test if an
      notification method (URI) is supported.

   o  Added a new capability response to ManageSieve that allows to
      report supported notification types.

































Melnikov, et al.         Expires August 4, 2007                 [Page 4]


Internet-Draft       Sieve Extension: Notifications         January 2007


Table of Contents

   1.    Introduction . . . . . . . . . . . . . . . . . . . . . . . .  6
   1.1.  Conventions used in this document  . . . . . . . . . . . . .  6

   2.    Capability Identifier  . . . . . . . . . . . . . . . . . . .  6

   3.    Notify Action  . . . . . . . . . . . . . . . . . . . . . . .  6
   3.1.  Notify Action Syntax and Semantics . . . . . . . . . . . . .  6
   3.2.  Notify parameter "method"  . . . . . . . . . . . . . . . . .  6
   3.3.  Notify tag ":from" . . . . . . . . . . . . . . . . . . . . .  7
   3.4.  Notify tag ":importance" . . . . . . . . . . . . . . . . . .  7
   3.5.  Notify tag ":options"  . . . . . . . . . . . . . . . . . . .  8
   3.6.  Notify tag ":message"  . . . . . . . . . . . . . . . . . . .  8
   3.7.  Examples . . . . . . . . . . . . . . . . . . . . . . . . . .  8
   3.8.  Requirements on notification methods specifications  . . . . 11

   4.    Extract_text Action  . . . . . . . . . . . . . . . . . . . . 12

   5.    Test valid_notify_method . . . . . . . . . . . . . . . . . . 13

   6.    Interactions with Other Sieve Actions  . . . . . . . . . . . 14

   7.    Security Considerations  . . . . . . . . . . . . . . . . . . 14

   8.    IANA Considerations  . . . . . . . . . . . . . . . . . . . . 14

   9.    Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 15

   10.   References . . . . . . . . . . . . . . . . . . . . . . . . . 15
   10.1. Normative References . . . . . . . . . . . . . . . . . . . . 15
   10.2. Informative References . . . . . . . . . . . . . . . . . . . 16

         Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 16
         Intellectual Property and Copyright Statements . . . . . . . 18
















Melnikov, et al.         Expires August 4, 2007                 [Page 5]


Internet-Draft       Sieve Extension: Notifications         January 2007


1.  Introduction

   This is an extension to the Sieve language defined by [Sieve] for
   providing instant notifications.  It defines the new action "notify".

   This document does not specify the notification methods.  Examples of
   possible notification methods are email and XMPP.  To allow a
   mechanism for portability of scripts that use notifications,
   implementation of the [MailTo] method is mandatory.  Other available
   methods shall depend upon the implementation and configuration of the
   system.

1.1.  Conventions used in this document

   Conventions for notations are as in [Sieve] section 1.1, including
   the use of [ABNF].

   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 [Kwds].


2.  Capability Identifier

   The capability string associated with the extension defined in this
   document is "enotify".


3.  Notify Action

3.1.  Notify Action Syntax and Semantics

   Usage:  notify [":from" string]
           [":importance" <"1" / "2" / "3">]
           [":options" string-list]
           [":message" string]
           <method: string>

   The Notify action specifies that a notification should be sent to a
   user.  The format of the notification is implementation-defined and
   is also affected by the notification method used (see Section 3.2).
   However, all content specified in the :message parameter SHOULD be
   included.

3.2.  Notify parameter "method"

   The method positional parameter identifies the notification method
   that will be used; it is a URI [URI].  For example, the notification



Melnikov, et al.         Expires August 4, 2007                 [Page 6]


Internet-Draft       Sieve Extension: Notifications         January 2007


   method can be an SMS URI [SMS-URI] containing a phone number, or an
   XMPP [XMPP] URI containing an XMPP identifier [XMPP-URI].

   The supported URI values will be site-specific, but support for the
   [MailTo] method is REQUIRED in order to insure interoperability.  If
   a URI schema is specified that the implementation does not support,
   the notification MUST cause an error condition.  Sieve scripts can
   check the supported methods using the "valid_notify_method" test to
   be sure that they only use supported ones, to avoid such error
   conditions.

   If the method parameter contains a supported URI schema, then the URI
   MUST be checked for syntactic validity.  An invalid URI syntax or an
   unsupported URI extension MUST cause an error.  An implementation MAY
   enforce other semantic restrictions on URIs -- for example an SMS URI
   can only contain phone numbers in a particular geographical region --
   and will treat violations of such semantic restrictions as errors.

3.3.  Notify tag ":from"

   A ":from" parameter may be used to specify an author of the
   notification.  The syntax of this parameter's value is method-
   specific.  Implementations SHOULD check the syntax according to the
   notification method specification and generate an error when a
   syntactically invalid ":from" parameter is specified.  In order to
   minimize/prevent forgery of the author value, implementations SHOULD
   impose restrictions on what values can specified in a ":from"
   parameter; it is suggested that values which fail such a validity
   check simply be ignored rather than causing the notify action to
   fail.

3.4.  Notify tag ":importance"

   The :importance tag specifies the importance of the delivery of the
   notification.  The :importance tag is followed by a numeric value
   represented as a string: "1" (high importance), "2" (normal
   importance), and "3" (low importance).  If no importance is given,
   the default value "2" SHOULD be assumed.  A notification method can
   treat the importance value as a transport indicator.  For example, it
   might deliver notifications of high importance quicker than
   notifications of normal or low importance.  Some notification methods
   allow users to specify their state of activity (for example "busy" or
   "away from keyboard").  If the notification method provides this
   information it SHOULD be used to selectively send notifications.  If,
   for example, the user marks herself as "busy", a notification method
   can require that a notification with importance of "3" is not to be
   sent, however the user should be notified of a notification with
   higher importance.



Melnikov, et al.         Expires August 4, 2007                 [Page 7]


Internet-Draft       Sieve Extension: Notifications         January 2007


   If the notification method allows users to filter messages based upon
   certain parameters in the message, users SHOULD be able to filter
   based upon importance.  If the notification method does not support
   importance, then this parameter MUST be ignored, however an
   implementation MAY include the importance value in the default
   message Section 3.6, if one is not provided.

3.5.  Notify tag ":options"

   The :options tag is used to send additional parameters to the
   notification method.  Interpretation of the parameters is method-
   specific.  This document doesn't specify any such additional
   parameter.

   Each string in the options string list has the following syntax:
   "<optionname>=<value>" [[Alexey 3: Should we say something about
   implementation prefix for implementation specific options?  Something
   like "x-Vendor-zzz".  If we don't say it now, it might be too late to
   say it later.]]

3.6.  Notify tag ":message"

   The :message tag specifies the message data to be included in the
   notification.  The entirety of the string SHOULD be sent but
   implementations MAY shorten the message for technical or aesthetic
   reasons.  If the message parameter is absent, a default
   implementation-specific message is used.  Unless specified otherwise
   by a particular notification mechanism, an implementation default
   containing at least the value of the "From" header field and the
   value of the "Subject" header field is RECOMMENDED.

   In order to construct more complex messages the notify extension can
   be used together with the Sieve variables extension [Variables], as
   shown in the examples below.

3.7.  Examples















Melnikov, et al.         Expires August 4, 2007                 [Page 8]


Internet-Draft       Sieve Extension: Notifications         January 2007


   Example 1:
       require ["enotify", "fileinto", "variables"];

       if header :contains "from" "boss@example.org" {
           notify :importance "1"
               :message "This is probably very important"
                           "mailto:alm@example.com";
           # Don't send any further notifications
           stop;
       }

       if header :contains "to" "sievemailinglist@example.org" {
           # :matches is used to get the value of the Subject header
           if header :matches "Subject" "*" {
               set "subject" "${1}";
           }

           # :matches is used to get the value of the From header
           if header :matches "From" "*" {
               set "from" "${1}";
           }

           notify :importance "3"
               :message "[SIEVE] ${from}: ${subject}"
               "mailto:alm@example.com";
           fileinto "INBOX.sieve";
       }
























Melnikov, et al.         Expires August 4, 2007                 [Page 9]


Internet-Draft       Sieve Extension: Notifications         January 2007


   Example 2:
       require ["enotify", "fileinto", "variables", "envelope"];

       if header :matches "from" "*@*.example.org" {
           # :matches is used to get the MAIL FROM address
           if envelope :all :matches "from" "*" {
               set "env_from" " [really: ${1}]";
           }

           # :matches is used to get the value of the Subject header
           if header :matches "Subject" "*" {
               set "subject" "${1}";
           }

           # :matches is used to get the address from the From header
           if address :matches :all "from" "*" {
               set "from_addr" "${1}";
           }

           notify :message "${from_addr}${env_from}: ${subject}"
                           "mailto:alm@example.com";
       }





























Melnikov, et al.         Expires August 4, 2007                [Page 10]


Internet-Draft       Sieve Extension: Notifications         January 2007


 Example 3:
     require ["enotify", "variables"];

     set "notif_method"
     "xmpp:tim@example.com?message;subject=SIEVE;body=You%20got%20mail";

     if header :contains "subject" "Your dog" {
         set "notif_method" "sms:+14085551212";
     }

     if header :contains "to" "sievemailinglist@example.org" {
         set "notif_method" "";
     }

     if not string :is "${notif_method}" "" {
         notify "${notif_method}";
     }

     if header :contains "from" "boss@example.org" {
         # :matches is used to get the value of the Subject header
         if header :matches "Subject" "*" {
             set "subject" "${1}";
         }

         # don't need high importance notification for
         # a 'for your information'
         if not header :contains "subject" "FYI:" {
             notify :importance "1" :message "BOSS: ${subject}"
                                "sms:+14085551212";
         }
     }

3.8.  Requirements on notification methods specifications

   This section describes requirements for documents that define
   specific Sieve notification methods.

   A notification method MAY allow modification of the final
   notification text -- for example, truncating it if it exceeds a
   length limit, or modifying characters that can not be represented in
   the target character set.  Characters in the notification text which
   can't be represented by the notification method SHOULD be replaced
   with a symbol indicating an unknown character.  Allowed modifications
   MUST be documented in the document describing the notification
   method.

   A notification method MAY ignore parameters specified in the Notify
   action.



Melnikov, et al.         Expires August 4, 2007                [Page 11]


Internet-Draft       Sieve Extension: Notifications         January 2007


   A notification method MAY recommend the default message value to be
   used if the :message argument is not specified.

   Notifications SHOULD include timestamps, if the notification method
   allows for their transmission outside of the textual message.
   Implementation methods which can only transmit timestamps in the
   textual message MAY include them in the textual message.

   Notifications SHOULD includes means to identify/track its origin, in
   order to allow a recipient to stop notifications or find out how to
   contact the sender.  This requirement is to help tracking a
   misconfigured or abusive origin of notifications.

   Methods SHOULD NOT include any other extraneous information not
   specified in parameters to the notify action.

   Methods MUST specify which URI parameters (if any) must be ignored
   and which ones must be used in the resulting notification.

   If there are errors sending the notification, the Sieve interpreter
   SHOULD ignore the notification and not retry indefinitely.  The Sieve
   interpreter MAY throttle notifications; if it does, a request to send
   a notification can be silently ignored.  Documents describing
   notification methods SHOULD describe how retries, throttling,
   duplicate suppression (if any), etc. are to be handled by
   implementations.


4.  Extract_text Action

   Usage:  extract_text [MODIFIER] [":first" number]
           <varname: string>

   The Extract_text action stores at most :first bytes of the first
   text/* part in the variable identified by varname.  If the :first
   parameter is not present, the whole content of the first text/* part
   is stored.  In either case the actually stored data MAY be truncated
   to conform to implementation specific limit on variable length and/or
   on MIME body part length.

   If the message being processed doesn't contain any text/* part, the
   action will set the variable identified by varname to the empty
   string.  [[Alexey 5: Do we need to be more specific about what "the
   first text part" means?]]

   Modifiers are applied on the extracted text before it is stored in
   the variable.  See [Variables] for details.




Melnikov, et al.         Expires August 4, 2007                [Page 12]


Internet-Draft       Sieve Extension: Notifications         January 2007


   Note that this action is only available when the Sieve script
   specifies both "variables" [Variables] and "enotify" capabilities in
   the require statements.



   Example 4:
       require ["enotify", "variables"];

       if header :contains "from" "boss@example.org" {
           # :matches is used to get the value of the Subject header
           if header :matches "Subject" "*" {
               set "subject" "${1}";
           }

           # extract the first 100 bytes of the first text/* part
           extract_text :first 100 "msgcontent";

           # don't need high importance notification for
           # a 'for your information'
           if not header :contains "subject" "FYI:" {
               notify :importance "1"
                      :message "BOSS: ${subject}; ${msgcontent}"
                                      "sms:+14085551212";
           }
       }



5.  Test valid_notify_method

   Usage:  valid_notify_method <notification-uris: string-list>

   The "valid_notify_method" test is true if the notification methods
   listed in the notification-uris argument are supported and they are
   syntactically and semantically (including implementation-specific
   semantic restrictions) valid.  This test MUST perform exactly the
   same validation as would be performed on the "method" parameter to
   the "notify" action.

   The test is true only if ALL of the listed notification methods are
   supported and valid.



   Example 5:
             if not valid_notify_method ["mailto:",
                     "http://gw.example.net/notify?test"] {



Melnikov, et al.         Expires August 4, 2007                [Page 13]


Internet-Draft       Sieve Extension: Notifications         January 2007


                 stop;
             }


6.  Interactions with Other Sieve Actions

   The notify action is compatible with all other actions, and does not
   affect the operation of other actions.  In particular, the notify
   action MUST NOT cancel the implicit keep.

   Multiple executed notify actions are allowed.  Specific notification
   methods MAY allow multiple notifications from the same script to be
   collapsed into one.


7.  Security Considerations

   Security considerations are discussed in [Sieve].  Additionally,
   implementations must be careful to follow the security considerations
   of the specific notification methods.

   The notify action is potentially very dangerous.  The path the
   notification takes through the network may not be secure.  An error
   in the options string may cause the message to be transmitted to
   someone it was not intended for, or may expose information to
   eavesdroppers.

   Just because a notification is received doesn't mean that it was sent
   by the Sieve implementation.  It might be possible to forge
   notifications with some notification methods.

   An organization may have a policy about the forwarding of classified
   information to unclassified networks.  Unless the policy is also
   enforced in the module responsible for generating (or sending) of
   notifications, users can use the extension defined in this document
   to extract classified information and bypass the policy.

   Notifications can result in loops and bounces.  [[Michael suggested
   to delete this example: In particular, a notification to an email
   address will not contain necessary Received header fields that might
   be otherwise used to prevent mail loops.]]  All notification methods
   must take care to provide mechanisms for avoiding notification loops.


8.  IANA Considerations

   The following template specifies the IANA registration of the notify
   Sieve extension specified in this document:



Melnikov, et al.         Expires August 4, 2007                [Page 14]


Internet-Draft       Sieve Extension: Notifications         January 2007


   To: iana@iana.org
   Subject: Registration of new Sieve extension
   Capability name: enotify
   Description: adds the 'notify' action for notifying user about the
   received message; also adds the 'extract_text' action for extracting
   a part of the first textual bodypart.
   RFC number: this RFC
   Contact address:
       The Sieve discussion list <ietf-mta-filters@imc.org>

   This information should be added to the list of sieve extensions
   given on http://www.iana.org/assignments/sieve-extensions.


9.  Acknowledgements

   Thanks to Larry Greenfield, Sarah Robeson, Tim Showalter, Cyrus
   Daboo, Nigel Swinson, Kjetil Torgrim Homme, Michael Haardt, Mark E.
   Mallett, Ned Freed, Lisa Dusseault, Dilyan Palauzov and Peter Saint-
   Andre for help with this document.


10.  References

10.1.  Normative References

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

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

   [MailTo]   Leiba, B. and M. Haardt, "Sieve Notification Mechanism:
              mailto", work in progress, draft-ietf-sieve-notify-mailto,
              October 2006.

   [Sieve]    Guenther, P. and T. Showalter, "Sieve: An Email Filtering
              Language", work in progress, draft-ietf-sieve-3028bis,
              August 2006.

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

   [Variables]
              Homme, K., "Sieve Extension: Variables", work in
              progress, draft-ietf-sieve-variables, December 2005.




Melnikov, et al.         Expires August 4, 2007                [Page 15]


Internet-Draft       Sieve Extension: Notifications         January 2007


10.2.  Informative References

   [SMS-URI]  Wilde, E. and A. Vaha-Sipila, "URI scheme for GSM Short
              Message Service", work in progress, draft-wilde-sms-uri,
              August 2005.

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

   [XMPP-URI]
              Saint-Andre, P., "Internationalized Resource Identifiers
              (IRIs) and Uniform Resource Identifiers (URIs) for the
              Extensible Messaging and Presence Protocol (XMPP)", work
              in progress, draft-saintandre-xmpp-iri, September 2005.


Authors' Addresses

   Alexey Melnikov (editor)
   Isode Limited
   5 Castle Business Village
   36 Station Road
   Hampton, Middlesex  TW12 2BX
   UK

   Email: Alexey.Melnikov@isode.com


   Barry Leiba (editor)
   IBM T.J. Watson Research Center
   19 Skyline Drive
   Hawthorne, NY  10532
   US

   Phone: +1 914 784 7941
   Email: leiba@watson.ibm.com


   Wolfgang Segmuller
   IBM T.J. Watson Research Center
   19 Skyline Drive
   Hawthorne, NY  10532
   US

   Phone: +1 914 784 7408
   Email: werewolf@us.ibm.com





Melnikov, et al.         Expires August 4, 2007                [Page 16]


Internet-Draft       Sieve Extension: Notifications         January 2007


   Tim Martin
   BeThereBeSquare Inc.
   672 Haight st.
   San Francisco, CA  94117
   US

   Phone: +1 510 260-4175
   Email: timmartin@alumni.cmu.edu











































Melnikov, et al.         Expires August 4, 2007                [Page 17]


Internet-Draft       Sieve Extension: Notifications         January 2007


Full Copyright Statement

   Copyright (C) The IETF Trust (2007).

   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).





Melnikov, et al.         Expires August 4, 2007                [Page 18]


Html markup produced by rfcmarkup 1.129d, available from https://tools.ietf.org/tools/rfcmarkup/