Network Working Group                                           A. Niemi
Internet-Draft                                          M. Garcia-Martin
Expires: July 1, 2004                                              Nokia
                                                            January 2004


 Multi-party Message Sessions using the Message Session Relay Protocol
                                 (MSRP)
                       draft-niemi-simple-chat-00

Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC2026.

   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on July 1, 2004.

Copyright Notice

   Copyright (C) The Internet Society (2004). All Rights Reserved.

Abstract

   The Message Session Relay Protocol (MSRP) defines a mechanism for
   sending instant messages within a session, established using the
   Session Initiation Protocol (SIP). This document describes how MSRP
   can be used to create multi-party message sessions using the tightly
   coupled conferencing model. It defines conventions and extensions for
   enabling features similar to many existing services in the Internet,
   e.g., Internet Relay Chat (IRC) based chat rooms, such as setting up
   nicknames, sending private messages to a subset of the multy-party
   conferece, etc.





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Table of Contents

   1.    Introduction . . . . . . . . . . . . . . . . . . . . . . . .  3
   1.1   Document Conventions . . . . . . . . . . . . . . . . . . . .  3
   1.2   Definitions  . . . . . . . . . . . . . . . . . . . . . . . .  3
   2.    Motivation . . . . . . . . . . . . . . . . . . . . . . . . .  4
   3.    Requirements . . . . . . . . . . . . . . . . . . . . . . . .  4
   4.    Multiparty Message Sessions and Conferencing . . . . . . . .  4
   4.1   Creating/deleting a chat room  . . . . . . . . . . . . . . .  4
   4.2   Sending and receiving messages within a chat room  . . . . .  5
   4.3   Nicknames  . . . . . . . . . . . . . . . . . . . . . . . . .  5
   4.3.1 Representation of a nickname . . . . . . . . . . . . . . . .  6
   4.3.2 Provision of nicknames to the focus  . . . . . . . . . . . .  7
   4.3.3 Procedures at the focus with respect nicknames . . . . . . . 12
   5.    IANA Considerations  . . . . . . . . . . . . . . . . . . . . 12
   5.1   MIME Registration for application/nickname-info+xml  . . . . 12
   5.2   URN Sub-Namespace Registration for
         urn:ietf:params:xml:ns:nickname-info . . . . . . . . . . . . 13
   5.3   Schema Registration  . . . . . . . . . . . . . . . . . . . . 14
   6.    Security Considerations  . . . . . . . . . . . . . . . . . . 14
         Normative References . . . . . . . . . . . . . . . . . . . . 14
         Informative References . . . . . . . . . . . . . . . . . . . 15
         Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 15
         Intellectual Property and Copyright Statements . . . . . . . 16



























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1. Introduction

   The Message Session Relay Protocol (MSRP) [12] defines a mechanism
   for sending a series of Instant Messages within a session. The
   Session Initiation Protocol (SIP) [6] allows for two peers to set up
   such a session.

   In another application of SIP, a user agent can join in a multi-party
   session or a conference that is hosted by a specialized user agent
   called a conference focus [11]. Such a conference can naturally
   involve an MSRP session as media, where an Instant Message received
   from one participant is relayed to all the other participants.

   Such a multi-party Instant Messaging would typically be referred to
   as a chat room. Several of these types of chat rooms already exist in
   the Internet. Some of these chat rooms include a rich set of
   features, such as the ability of a participant to send private
   messages to one or more participants, or to establish sub-conferences
   within the existing conference.

   The aim of this document is to define conventions and extensions for
   enabling features similar to many of these existing applications in
   the Internet, e.g., Internet Relay Chat (IRC) based chat rooms. This
   memo uses the SIP Conferencing Framework [11] as a design base to
   define a set of extensions to SIP and SDP that enrich session based
   messaging conferences.

1.1 Document Conventions

   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 RFC 2119 [1] and
   indicate requirement levels for compliant implementations.

1.2 Definitions

   This memo deals with a particular case of tightly coupled SIP
   conferences where the media exchanged consist of session based
   messaging. Unless otherwise noted, we use the terminology defined in
   the SIP Conferencing Framework [11] applied to the scope of this
   document. In addition to that terminology, we introduce some new
   terms:

   Nickname:  a descriptive name associated to a participant. A nickname
      is non-routable pseudonym that the participant chooses for the
      purpose of additional identification towards the rest of the
      participants.




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   Session based message conference:  a particular case of a tightly
      coupled SIP conference (as defined by the SIP Conferencing
      Framework [11]) where the media exchanged between the participants
      consist of session based instant messages transported with MSRP.
   Session based message mixer:  a particular case of a mixer (as
      defined by the SIP Conferencing Framework [11]) where the media
      exchanged to or from the participants consist of session based
      instant messages transported with MSRP.
   Private instant message:  an instant message whose intended list of
      destinations is a subset of the participants, rather than all the
      participants of the conference.

2. Motivation

   As SIP already provides a Conferencing Framework [11] that can be
   utilized in many types of conferencing applications, it seems
   beneficial to provide a set of features that when used specifically
   with MSRP, enhance the Instant Messaging conferences in order to
   compete in functionality with existing systems.

3. Requirements

   Requirements that enrich the session based messaging conferences have
   been already described in Requirements for Instant Messaging in 3GPP
   Wireless Systems [9] or the Advanced Instant Messaging Requirements
   for the Session Initiation Protocol [10].

4. Multiparty Message Sessions and Conferencing

4.1 Creating/deleting a chat room

   Since we consider a chat room a particular type of conferences where
   the media happens to be session based messaging (MSRP), the methods
   defined by the SIP Conference Framework to create and delete
   conferences are applicable to the session based message conferences.

   Once a session based message conference is created, the conference is
   identified by a URI, like any other conference. Participants are
   aware that the peer is a focus due to the presence of the "isfocus"
   feature tag in the Contact header field of the 2xx-class response to
   the INVITE request. Participants are also aware that the mixer is a
   session based messaging mixer due to the presence of the message
   media type and the MSRP protocol in the SDP.

   In a one-to-one MSRP session, received Instant Messages are
   identified by the transport connection on which they arrive. In a
   chat room, where a single transport connection to the conference
   mixer is used for receiving Instant Messages from all of the other



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   conference participants, this is not sufficient. Each message needs
   to carry in it an identifier of the sender of the message.

   This is accomplished using the 'message/cpim' MIME type, as defined
   in [7]. The conference focus MUST insist on using the 'message/cpim'
   as the top-level wrapper type in the SDP, as defined in [12].

4.2 Sending and receiving messages within a chat room

   MSRP provides for the existence of a SEND primitive that allows a
   sender to transport an instant message to the receiver. The actual is
   enclosed in a body. MSRP mandates implementations to support the
   message/cpim format. A participant that sends an MSRP SEND request to
   a session based message focus SHOULD enclose the contents of the
   actual message in a message/cpim MIME-type format. The message/cpim
   format allows to wrap other message formats such as text/plain, text/
   html, etc.

      NOTE: Wrapping the actual contents into a message/cpim provides
      the session based messaging focus with better CPIM compatibility.
      Additionally, the focus may need to distribute copies of the
      messages to the rest of the participants in a message/cpim format,
      thus, if the sender sends the message already in message/cpim
      format the focus is relieved from the task of doing format
      conversion.

   A participant that sends an session based instant message to the
   conference mixer SHOULD include her nickname in the From header of
   the message/cpim wrapper (see the nicknames discussion in Section
   Section 4.3.

   A participant that sends an session based instant message addressed
   to the conference MUST set the To header of the message/cpim to the
   conference URI.

   A participant that sends a session based private instant message to
   one or more participants of the conference MUST include the nickname
   of the each of the intended receivers in either the To or Cc headers
   of the message/cpim.

      OPEN ISSUE: the paragraph above assumes that the participant
      receives somehow the nicknames of each of the participants. Is
      this assumption valid? Will the conference package have elements
      to include nicknames? Or shall we define that extension?

4.3 Nicknames

   A common characteristic of existing focuses is that participants have



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   the ability to identify themselves with a nickname to the rest of the
   participants in a conference. A nickname is a string of characters
   that serves for the purpose of identifying a participant to the rest
   of the participants of the conference. A nickname can match the
   participant name, or identify any characteristic, but it can be any
   other string that is not associated with the participant at all. A
   nickname can be also a collection of characters that do not make
   sense in any language, as a mechanism to provide some anonymity of
   the nickname.

   Users are allowed to choose any nickname of their wish when they join
   the conference. The only prerequisite is that the nickname is not
   already in used by another participant. The nickname ought to be
   unique within the set of conference instances managed by the focus.
   This property allows a participant to join several conferences in the
   same and still keep the same nickname across all those conferences.
   Note that we don't require a nickname to be globally unique, but just
   locally unique within the focus.

   Nicknames are non-routable identifiers. A participant of a conference
   cannot derive the SIP URI or IP address out of the nickname chosen by
   another participant. Certainly the focus binds nicknames with their
   respective SIP URIs, however, this binding exists only in the focus
   and is not visible to the participants of the conference. This
   property allows also a participant to send a private instant message
   to a second participant who is identified only by her nickname.

4.3.1 Representation of a nickname

   A nickname is syntactically defined as the combination of a display
   name and an IM URI. The IM URI [8] may be a non-routable URI, since
   the purpose of the URI is not to identify a SIP entity. This avoids
   routing based on the contents of a nickname. A non routable URI may
   be created by appending ".invalid" to an existing domain name.

   We define conventions that allow to a sender to include a nickname in
   the From, To or Cc headers of a message/cpim document. These headers
   are already defined in the CPIM message format [7] with the following
   syntax:

             From-header = "From" ": " [ Formal-name ] "<" URI ">"
             To-header   = "To"   ": " [ Formal-name ] "<" URI ">"
             Cc-header   = "cc"   ": " [ Formal-name ] "<" URI ">"

   A non-routable IM URI follows the format of a Network Access
   Identifier (NAI) (RFC 2486) [3]. Appending the domain ".invalid" to a
   NAI can make it non-routable. We chose an IM URI rather than a SIP
   URI since the purpose of the URI is not to identify a SIP entity.



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   Examples of nickname:

               "Prince of the snow" <im:johnny@example.com.invalid>

   A nickname is scoped to be valid in the focus address space. The
   focus maintains a binding between nicknames and SIP URIs that allows
   to route private instant messages to the appropriate participant.
   However, this binding is not visible outside the focus, in
   particular, it is not visible to the participants of the conference.

   We represent nicknames in the From, To and Cc headers in the message/
   cpim. If the message is a addressed to the whole conference, the To
   header of the CPIM message contains the conference URI. If the
   message is a private message address to a subset of the participants,
   To and Cc headers include the nickname of each of the intended
   recipients. The following examples shows a CPIM private message sent
   from a participant to a subset of the conference participants.

          Content-Type: message/cpim

          From: "Prince of the snow" <im:johnny@example.com.invalid>
          To: "Blue Arrow" <im:bluearrow@example.com.invalid>
          To: "Daisy" <im:daisy@example.com.invalid>
          Cc: "Hook" <im:doe@example.com.invalid>
          DateTime: 2004-01-28T15:43:00-02:00

          Content-Type: text/plain
          Content-ID: <092380923@foo.com>

          This is an example of a private instant message


4.3.2 Provision of nicknames to the focus

   A participant of a conference controlled by a particular focus can
   setup his nickname by any means outside the scope of this document.
   For instance, the participant can log into a web page where he
   authenticates and sets up his nickname.

   We also provide a mechanism that allows a participant to setup his
   nickname interactively with the focus. The mechanism is based on the
   exchange of XML "application/nickname-info+xml" documents. We define
   the "application/nickname-info+xml" in Section Section 4.3.2.1.

   The mechanism is inspired in the SDP offer/answer model, but instead,
   we define an XML "application/nickname-info+xml" offer/answer model.
   Any SIP request or responde can carry an "application/
   nickname-info+xml" offer document, where the oferer express a request



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   to set her nickname. The focus response with an XML "application/
   nickname-info+xml" answer where it authorizes or denies the request,
   or makes another suggestion.

4.3.2.1 The application/nickname-info+xml data format

   We define a nickname information XML document that is used to
   request, setup, and suggest other nicknames to a focus. Users of this
   specifications MUST support the "application/nickname-info+xml" data
   format and MAY support other data formats. As a consequence, the
   Accept header field in SIP messages MUST contain the "application/
   nickname-info+xml" and MAY contain other types capable of
   representing a nickname.

   Nickname information is an XML document that MUST be well-formed and
   SHOULD be valid. Nickname information documents MUST be based on XML
   1.0 and MUST be encoded using UTF-8. This specification makes use of
   XML namespaces for identifying Nickname information documents. The
   namespace URI for elements defined by this specification is a URN
   [2], using the namespace identifier 'ietf' defined by RFC 2648 [4]
   and extended by [13]. This URN is:
      urn:ietf:params:xml:ns:nickname-info

   A Nickname information document begins with the root element tag
   "nickname-info" that contains a "version" attribute and an "entity"
   attribute

   The first time an offerer crates an offer, it initializes the
   "version" attribute to 0. Every time either the offerer or the answer
   crates a new offer or answer based on a previous document, it
   increments the version number by one. Versions are scoped by the pair
   of participant and focus.

   The "entity" attribute identifies the participant's URI whose
   nickname is being set. Most focuses will contain policy that
   disallows the own SIP URI to modify her own nickname, however
   policies are outside the scope of this memo.

   The "nickname-info" element contains a series of zero or more
   "nickname" child elements

   The "nickname" element contains information on a particular nickname.
   It has a two mandatory attributes, "id" and "state". The "id"
   attribute provides a single string that can be used as an identifier
   for this nickname. The "id" is created the first time the nickname is
   used. The "state" attribute carries the state of the nickname.
   Possible values are "suggested", indicating that the participant
   suggest a nickname for the entity; "confirmed", indicating that the



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   focus has confirmed that the nickname is unique and allocated to the
   entity; "denied" indicating that the focus does not authorize the
   usage of the nickname. In case the state is set to denied, an
   optional "reason" attribute can further indicate the reason of
   denial: "in-use" if the suggested nickname is already in use, or
   "policy" to indicate that the focus has some policy that denies the
   nickname (e.g., offensive word).

   The "nickname" element contains a "display-name" child element that
   contains the nickname display string that most application will
   render to the user. The "nickname" element can also contain a "uri">
   child element. A participant MUST NOT set the "uri" element. The
   focus SHOULD set it to a non-routable IM URI that belongs to the
   address space of the focus. A participant SHOULD use his URI in the
   From header of a message/cpim message when it sends an instant
   message.

4.3.2.2 XML schema

   The following is the schema for the application/nickname-info+xml
   type:



   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema targetNamespace="urn:ietf:params:xml:ns:nickname-info"
              xmlns:xs="http://www.w3.org/2001/XMLSchema"
              xmlns:tns="urn:ietf:params:xml:ns:nickname-info"
              elementFormDefault="qualified"
              attributeFormDefault="unqualified">
     <!-- This import brings in the XML language attribute xml:lang-->
     <xs:import namespace="http://www.w3.org/XML/1998/namespace"
                schemaLocation="http://www.w3.org/2001/03/xml.xsd"/>
     <xs:element name="nickname-info">
        <xs:complexType>
           <xs:sequence>
              <xs:element ref="tns:nickname" maxOccurs="unbounded"/>
              <xs:any namespace="##other" processContents="lax"
                      minOccurs="0" maxOccurs="unbounded"/>
           </xs:sequence>
           <xs:attribute name="version"
                         type="xs:nonNegativeInteger"
                         use="required"/>
          <xs:attribute name="state" use="required">
             <xs:simpleType>
                <xs:restriction base="xs:string">
                   <xs:enumeration value="full"/>
                   <xs:enumeration value="partial"/>



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               </xs:restriction>
             </xs:simpleType>
          </xs:attribute>
          <xs:attribute name="entity" type="xs:anyURI" use="required"/>
       </xs:complexType>
     </xs:element>
     <xs:element name="nickname">
         <xs:complexType>
            <xs:sequence>
               <xs:element ref="tns:display-name"
                           minOccurs="1" maxOccurs="1"/>
               <xs:element ref="tns:uri"
                           minOccurs="1" maxOccurs="1"/>
            </xs:sequence>
            <xs:attribute name="id" type="xs:string" use="required"/>
            <xs:attribute name="state" use="required">
               <xs:simpleType>
                  <xs:restriction base="xs:string">
                     <xs:enumeration value="suggested"/>
                     <xs:enumeration value="confirmed"/>
                     <xs:enumeration value="denied"/>
                  </xs:restriction>
               </xs:simpleType>
            </xs:attribute>
            <xs:attribute name="reason" use="optional">
               <xs:simpleType>
                  <xs:restriction base="xs:string">
                     <xs:enumeration value="in-use"/>
                     <xs:enumeration value="policy"/>
                  </xs:restriction>
               </xs:simpleType>
            </xs:attribute>
         </xs:complexType>
     </xs:element>
     <xs:element name="display-name" type="xs:string"/>
     <xs:element name="uri" type="xs:anyURI"/>
   </xs:schema>


4.3.2.3 Examples

   A participant has joined a session based messaging conference. She
   wants to setup a nickname, so she sends a SIP request that includes
   the following "application/nickname-info+xml" body. The document does
   not contain a URI, since URIs are set by the focus, it only contains
   the display name part of the nickname. The state is set to
   "suggested" since this is only a suggestion that needs to be
   confirmed by the focus.



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       <?xml version="1.0"?>
         <nickname-info xmlns="urn:ietf:params:xml:ns:nickname-info"
                      version="0"
                      entity="sip:blue@example.com">
             <nickname id="486586ds" state="suggested">
                <display-name>Daisy</display-name>
             </nickname>
         </nickname-info>

   Let's assume that the nickname is taken by another user. The focus
   sends a new XML body in a SIP message, where it steps up the version
   number in the document. The state of the nickname is set to "denied"
   and a "reason" is set to "in-use". The focus also suggest similar
   nicknames that are "available" for the participant to choose. The XML
   is:


       <?xml version="1.0"?>
         <nickname-info xmlns="urn:ietf:params:xml:ns:nickname-info"
                      version="1"
                      entity="sip:blue@example.com">
             <nickname id="486586ds" state="denied" reason="in-use"/>
             <nickname id="d82ms938" state="available">
             <display-name>Daisy44</display-name>
             </nickname>
             <nickname id="bkid92as" state="available">
             <display-name>Daisy49</display-name>
             </nickname>
         </nickname-info>

   The participant decides not to take any of the suggestions, but
   instead suggests a new nickname. She also steps up the version
   number.


       <?xml version="1.0"?>
         <nickname-info xmlns="urn:ietf:params:xml:ns:nickname-info"
                      version="2"
                      entity="sip:blue@example.com">
             <nickname id="m239wd4" state="suggested">
             <display-name>Blue Arrow</display-name>
             </nickname>
         </nickname-info>

   The focus of the conference verifies that the nickname is not in use
   by any other participant of any other conference. It internally binds
   the nickname with the SIP and MSRP URIs of the user. The focus steps
   up the version number, allocates an IM URI and returns the new



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   information in the XML body.


       <?xml version="1.0"?>
         <nickname-info xmlns="urn:ietf:params:xml:ns:nickname-info"
                      version="3"
                      entity="sip:blue@example.com">
             <nickname id="m239wd4" state="confirmed">
             <display-name>Blue Arrow</display-name>
             <uri>im:bluearrow@example.com.invalid</uri>
             </nickname>
         </nickname-info>


4.3.3 Procedures at the focus with respect nicknames

   Here we should describe that the focus verifies that the From header
   in the CPIM message is allocated to the user and keeps it in the CPIM
   message that sends to the rest of the participants.

5. IANA Considerations

   This document registers a new MIME type "application/
   nickname-info+xml" and new XML namespace.

5.1 MIME Registration for application/nickname-info+xml

   MIME media type name: application

   MIME subtype name: nickname-info+xml

   Mandatory parameters: none

   Optional parameters: Same as charset parameter application/xml as
   specified in RFC 3023 [5].

   Encoding considerations: Same as encoding considerations of
   application/xml as specified in RFC 3023 [5].

   Security considerations: See Section 10 of RFC 3023 [5] and Section 6
   of this specification.

   Interoperability considerations: none.

   Published specification: This document.

   Applications which use this media type: This document type has been
   used to support SIP applications in a multi-party session based



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   messaging environment.

   Additional Information:

   Magic Number: None

   File Extension: .nin or .xml

   Macintosh file type code: "TEXT"

   Personal and email address for further information: Miguel
   Garcia<miguel.an.garcia@nokia.com>

   Intended usage: COMMON

   Author/Change controller: The IETF.

5.2 URN Sub-Namespace Registration for
    urn:ietf:params:xml:ns:nickname-info

   This section registers a new XML namespace, as per the guidelines in
   [13].

   URI: The URI for this namespace is
   urn:ietf:params:xml:ns:nickname-info.

   Registrant Contact: IETF, SIMPLE working group,<simple@ietf.org>,
   Miguel Garcia, <miguel.an.garcia@nokia.com>.


   XML:

        BEGIN
        <?xml version="1.0"?>
        <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
                  "http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
        <html xmlns="http://www.w3.org/1999/xhtml">
        <head>
          <meta http-equiv="content-type"
             content="text/html;charset=iso-8859-1"/>
          <title>Nickname Information Namespace</title>
        </head>
        <body>
          <h1>Namespace for Nickname Information</h1>
          <h2>application/nickname-info+xml</h2>
          <p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>
        </body>
        </html>



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   END


5.3 Schema Registration

   This specification registers a schema, as per the guidelines in [13].

   URI: please assign.

   Registrant Contact: IETF, SIMPLE working group,<simple@ietf.org>,
   Miguel Garcia, <miguel.an.garcia@nokia.com>.

   XML: The XML can be found in Section 4.3.2.2.

6. Security Considerations

   In general, messages sent to a multy-party session based messaging
   focus are not deem to expose any security threat. Nevertheles, if a
   participant wants to avoid eavesdropping from non authorized
   entities, it should send those messages a TLS transport connection,
   as allowed by MSRP.

Normative References

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

   [2]  Moats, R., "URN Syntax", RFC 2141, May 1997.

   [3]  Aboba, B. and M. Beadles, "The Network Access Identifier", RFC
        2486, January 1999.

   [4]  Moats, R., "A URN Namespace for IETF Documents", RFC 2648,
        August 1999.

   [5]  Murata, M., St. Laurent, S. and D. Kohn, "XML Media Types", RFC
        3023, January 2001.

   [6]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
        Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP:
        Session Initiation Protocol", RFC 3261, June 2002.

   [7]  Atkins, D. and G. Klyne, "Common Presence and Instant Messaging:
        Message Format", draft-ietf-impp-cpim-msgfmt-08 (work in
        progress), January 2003.

   [8]  Peterson, J., "Common Profile for Instant Messaging (CPIM)",
        draft-ietf-impp-im-04 (work in progress), October 2003.



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Informative References

   [9]   Niemi, A., "Requirements for Instant Messaging in 3GPP Wireless
         Systems", draft-niemi-simple-im-wireless-reqs-02 (work in
         progress), October 2003.

   [10]  Rosenberg, J., "Advanced Instant Messaging Requirements for the
         Session Initiation Protocol  (SIP)",
         draft-rosenberg-simple-messaging-requirements-00 (work in
         progress), December 2002.

   [11]  Rosenberg, J., "A Framework for Conferencing with the Session
         Initiation Protocol",
         draft-ietf-sipping-conferencing-framework-01 (work in
         progress), October 2003.

   [12]  Campbell, B., "Instant Message Sessions in SIMPLE",
         draft-ietf-simple-message-sessions-02 (work in progress),
         October 2003.

   [13]  Mealling, M., "The IETF XML Registry",
         draft-mealling-iana-xmlns-registry-05 (work in progress), June
         2003.


Authors' Addresses

   Aki Niemi
   Nokia
   P.O. Box 321
   NOKIA GROUP, FIN  00045
   Finland

   Phone: +358 50 389 1644
   EMail: aki.niemi@nokia.com


   Miguel A. Garcia-Martin
   Nokia
   P.O. Box 407
   NOKIA GROUP, FIN  00045
   Finland

   Phone: +358 50 480 4586
   EMail: miguel.an.garcia@nokia.com






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