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Versions: (draft-lonnfors-simple-prescaps-ext) 00 01 02 03 04 05 06 07 08 09 10 RFC 5196

SIMPLE WG                                                    M. Lonnfors
Internet-Draft                                                   K. Kiss
Expires: April 24, 2005                                            Nokia
                                                        October 24, 2004



  User Agent Capability Extension to Presence Information Data Format
                                 (PIDF)
                   draft-ietf-simple-prescaps-ext-02


Status of this Memo


   This document is an Internet-Draft and is subject to all provisions
   of section 3 of RFC 3667.  By submitting this Internet-Draft, each
   author represents that any applicable patent or other IPR claims of
   which he or she is aware have been or will be disclosed, and any of
   which he or she become aware will be disclosed, in accordance with
   RFC 3668.


   Internet-Drafts are working documents of the Internet Engineering
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   This Internet-Draft will expire on April 24, 2005.


Copyright Notice


   Copyright (C) The Internet Society (2004).


Abstract


   Interoperation of Instant Messaging and Presence systems has been
   defined in the IMPP working group.  The IMPP WG has come up with
   baseline interoperable operations and formats for presence and
   instant messaging systems.  However, these base formats might need
   standardized extensions in order to enable building rational
   applications using presence and instant messaging.  This memo defines




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   an extension  to represent RFC3840 capabilities in the Presence
   Information Document Format (PIDF) compliant presence documents.


Table of Contents


   1.   Introduction . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1  Motivation . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.2  Scope  . . . . . . . . . . . . . . . . . . . . . . . . . .   5
   2.   Conventions  . . . . . . . . . . . . . . . . . . . . . . . .   5
   3.   Extension for "Indicating User Agent Capabilities in the
        Session Initiation Protocol (SIP)" in PIDF documents . . . .   5
     3.1  Overview of operation  . . . . . . . . . . . . . . . . . .   5
     3.2  Service capability document  . . . . . . . . . . . . . . .   6
       3.2.1  <servcaps> element . . . . . . . . . . . . . . . . . .   6
       3.2.2  <audio> element  . . . . . . . . . . . . . . . . . . .   6
       3.2.3  <application> element  . . . . . . . . . . . . . . . .   6
       3.2.4  <data> element . . . . . . . . . . . . . . . . . . . .   7
       3.2.5  <control> element  . . . . . . . . . . . . . . . . . .   7
       3.2.6  <video> element  . . . . . . . . . . . . . . . . . . .   7
       3.2.7  <text> element . . . . . . . . . . . . . . . . . . . .   7
       3.2.8  <message> element  . . . . . . . . . . . . . . . . . .   7
       3.2.9  <type> element . . . . . . . . . . . . . . . . . . . .   8
       3.2.10   <automata> element . . . . . . . . . . . . . . . . .   8
       3.2.11   <class> element  . . . . . . . . . . . . . . . . . .   8
       3.2.12   <duplex> element . . . . . . . . . . . . . . . . . .   8
       3.2.13   <description> element  . . . . . . . . . . . . . . .   9
       3.2.14   <event-packages> element . . . . . . . . . . . . . .   9
       3.2.15   <priority> element . . . . . . . . . . . . . . . . .   9
       3.2.16   <methods> element  . . . . . . . . . . . . . . . . .   9
       3.2.17   <extensions> element . . . . . . . . . . . . . . . .  10
       3.2.18   <schemes> element  . . . . . . . . . . . . . . . . .  10
       3.2.19   <actor> element  . . . . . . . . . . . . . . . . . .  10
       3.2.20   <isfocus> element  . . . . . . . . . . . . . . . . .  11
       3.2.21   <languages> element  . . . . . . . . . . . . . . . .  11
     3.3  Device capability document . . . . . . . . . . . . . . . .  12
       3.3.1  <devcaps> element  . . . . . . . . . . . . . . . . . .  12
       3.3.2  <mobility> element . . . . . . . . . . . . . . . . . .  12
       3.3.3  <priority> element . . . . . . . . . . . . . . . . . .  12
       3.3.4  <description> element  . . . . . . . . . . . . . . . .  13
   4.   Usage guidelines . . . . . . . . . . . . . . . . . . . . . .  13
   5.   Examples . . . . . . . . . . . . . . . . . . . . . . . . . .  13
     5.1  Example  . . . . . . . . . . . . . . . . . . . . . . . . .  13
   6.   XML schema definitions . . . . . . . . . . . . . . . . . . .  14
     6.1  Service capability document  . . . . . . . . . . . . . . .  14
     6.2  Device capability document . . . . . . . . . . . . . . . .  23
   7.   IANA Considerations  . . . . . . . . . . . . . . . . . . . .  25
     7.1  URN sub-namespace registration for
          'urn:ietf:params:xml:ns:pidf:servcaps' . . . . . . . . . .  25




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     7.2  URN sub-namespace registration for
          'urn:ietf:params:xml:ns:pidf:status:devcaps' . . . . . . .  26
   8.   Security Considerations  . . . . . . . . . . . . . . . . . .  27
   9.   Acknowledgments  . . . . . . . . . . . . . . . . . . . . . .  27
   10.  References . . . . . . . . . . . . . . . . . . . . . . . . .  27
   10.1   Normative references . . . . . . . . . . . . . . . . . . .  27
   10.2   Informative references . . . . . . . . . . . . . . . . . .  28
        Authors' Addresses . . . . . . . . . . . . . . . . . . . . .  29
        Intellectual Property and Copyright Statements . . . . . . .  30











































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1.  Introduction


   Interoperation of instant messaging and presence systems has been
   defined in IMPP working group.  Working group has defined "A model
   for Presence and Instant Messaging" in RFC2778 [2] and also
   requirements for protocols implementing such a system in RFC2779 [3].
   Common presence (CPP) [5] and common profile for instant messaging
   (CPIM) [13] defines common operations and formats which all presence
   and instant messaging services must agree upon so that basic
   interoperability would be possible.  The actual base format for the
   presence is defined in the Presence Information Document Format
   (PIDF) [4].  The PIDF has been designed to reduce the need for
   gatewaying and to allow end-to-end security of presence data.  It has
   taken very minimalistic approach to support such operations.  In
   order to make the PIDF usable by different presence applications,
   these applications usually must extend the basic PIDF by standard XML
   mechanisms as defined in the PIDF [4].


   The aim of this memo is to introduce a SIP specific extension
   mechanism to the PIDF that conveys the same SIP media feature tags as
   described in RFC3840 [6].  With this extension presence applications
   based on SIP can have richer and more usable presence data compared
   to the baseline PIDF.


1.1  Motivation


   The PIDF [4] defines a <contact> element which may appear once inside
   every <tuple> element.  The content of the <contact>  element encodes
   the CONTACT ADDRESS and CONTACT MEANS as defined in RFC2778 [2].  The
   <contact> element is defined to be a URI of any scheme.  In some
   implementations the URI scheme can uniquely identify the service the
   tuple intends to describe (e.g.  im: URI scheme usually represent
   Instant Messaging service).  However, this may not be the case in all
   implementations.  For example in SIP, a SIP URI scheme can represent
   different kinds of services.  A SIP URI scheme can be used to contact
   voice services, video services, or messaging services.  If it is not
   known by other means, it might be hard for applications processing
   the presence information document containing only a SIP URI contact
   addresses to know what particular service the tuple intends to
   describe.  Also watchers receiving presence information would
   probably benefit for getting more descriptive information about what
   particular communication means or services are supported by the
   presentity.


   RFC3840 [6] defines a set of extensions which allow callees to
   express preferences about request handling in SIP servers.  The same
   information can provide value also to presence watchers so that they
   can make more rational decisions on how a presentity should be




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   contacted if a presence document would contained similar information.


1.2  Scope


   This document defines extensions to the PIDF which enables presence
   implementations based on SIP to utilize similar information in a
   presence information document as what "RFC3840 [6] defines.


   This extension does not replace media negotiation mechanisms defined
   for SIP (e.g.  SDP [17]).  This extension is only aimed for
   presentities to give watchers hints about the presentity's
   preferences, willingness and capabilities to communicate before
   watchers initiate a communication with the presentity.


2.  Conventions


   In this document, the key words "MUST", "MUST NOT", "REQUIRED",
   "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
   and "OPTIONAL" are to be interpreted as described in RFC 2119 [1] and
   indicate requirement levels for compliant implementations.


   This memo makes use of the vocabulary defined in RFC2778 [2], and in
   PIDF [4].


3.  Extension for "Indicating User Agent Capabilities in the Session
   Initiation Protocol (SIP)" in PIDF documents


   This section presents all extension namespaces, their elements, their
   values, and semantics.  This section also describes how this
   extension can be further extended.  This extension is intended to be
   used within a PIDF [4] and that particular usage is described here.
   This extension may also be used with other XML documents if
   appropriate.


3.1  Overview of operation


   This document defines how the features presented in RFC3840 [6] can
   be provided as a part of presence data.  Additionally, this memo
   includes the "type" feature tag [7], "message" media type feature tag
   [18] and the "language" feature tag [8] definitions.  Bringing these
   features in the PIDF means mapping them to a XML formatted structure.


   The presence data model [11] defines presence data consisting of
   three types of data elements: person, service, and device.  This memo
   follows this model so that one XML document is defined to describe
   device capabilities and another to describe service capabilities.


   The namespace URIs for elements defined by this document are URNs




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   using the namespace identifier 'ietf' defined by RFC2648 [9] and
   extended by RFC3688 [10].


   When these extension namespaces are congregated with the PIDF
   document, the combined document MUST follow the same general
   formatting rules as specified in Section 4.1 of the PIDF [4].


3.2  Service capability document


   Elements belonging to this document are used to describe
   characteristics of a service as defined in the presence data model
   [11].  All elements defined in this section describe static data
   about the service.  This document SHOULD be located in PIDF document
   as a child element of urn:ietf:params:xml:ns:pidf namespace <tuple>
   [4] element.


   Namespace identifier for this document is
   urn:ietf:params:xml:ns:pidf:servcaps.


3.2.1  <servcaps> element


   The root element of the service capability document is <servcaps>.
   The root element has to be always present.  This element can contain
   one or more elements as specified later in this document.


   A <servcaps> element does not have any attributes and it can contain
   other namespace declarations for the extensions used in the presence
   XML document.


3.2.2  <audio> element


   The <audio> element indicates that the service supports audio as a
   streaming media type as defined in RFC3840 [6].


   The <audio> element is of boolean type and does not have any
   attributes.  The value 'true' indicates that service supports audio
   media type and the value 'false' indicates that service does not
   support audio media type.


3.2.3  <application> element


   The <application> element indicates that the service supports
   application as a streaming media type as defined in RFC3840 [6].


   The <application> element is of boolean type and does not have any
   attributes.  The value 'true' indicates that service supports
   application media type and the value 'false' indicates that service
   does not support application media type.




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3.2.4  <data> element


   The <data> element indicates that the service supports data as a
   streaming media type as defined in RFC3840 [6].


   The <data> element is of boolean type and does not have any
   attributes.  The value 'true' indicates that service supports data
   media type and the value 'false' indicates that service does not
   support data media type.


3.2.5  <control> element


   The <control> element indicates that the service supports control as
   a streaming media type as defined in RFC3840 [6].


   The <control> element is of boolean type and does not have any
   attributes.  The value 'true' indicates that service supports control
   media type and the value 'false' indicates that service does not
   support control media type.


3.2.6  <video> element


   The <video> element indicates that the service supports video as a
   streaming media type as defined in RFC3840 [6].


   The <video> element is of boolean type and does not have any
   attributes.  The value 'true' indicates that service supports video
   media type and the value 'false' indicates that service does not
   support video media type.


3.2.7  <text> element


   The <text> element indicates that the service supports text as a
   streaming media type as defined in RFC3840 [6].


   The <text> element is of boolean type and does not have any
   attributes.  the value 'true' indicates that service supports text
   media type and the value 'false' indicates that service does not
   support text media type.


3.2.8  <message> element


   The <message> element indicates that the service supports message as
   a streaming media type as defined in [18].


   The <message> element is of boolean type and does not have any
   attributes.  The value 'true' indicates that service supports message
   media type and the value 'false' indicates that service does not




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   support message media type.


3.2.9  <type> element


   The <type> element indicates indicates a MIME media content type
   (i.e.  that appears in a 'Content-type:' header of the corresponding
   MIME-formatted data) as defined in RFC2913 [7].


   The <type> element is of string type and does not have any
   attributes.  It MUST be a string of the form "type/subtype", where
   'type' and 'subtype' are defined by the MIME specification [19].
   Only lower-case letters SHOULD be used.


3.2.10  <automata> element


   The <automata> element indicates whether the service represents an
   automata (such as a voicemail server, conference server, IVR, or
   recording device) or a human as defined in RFC3840 [6].


   The <automata> element is of boolean type and does not have any
   attributes.  The value 'true' indicates that the service represents
   an automata and the value 'false' indicates that it represents a
   human.


3.2.11  <class> element


   The <class> element indicates the setting, business or personal, in
   which a communications service is used as defined in RFC3840 [6].


   The <class> element can contain two elements: <supported> and
   <notsupported>.  All classes that are supported by the service are
   listed under <supported> element and all classes that are not
   supported by the service are listed under <notsupported> element.


   Possible class values as defined in RFC3840 are: business and
   personal.


3.2.12  <duplex> element


   The <duplex> element lists whether a communications service can
   simultaneously send and receive media ("full"), alternate between
   sending and receiving ("half"), can only receive ("receive-only") or
   only send ("send-only") as defined in RFC3840 [6].


   The <duplex> element can contain two elements: <supported> and
   <notsupported>.  All duplex modes that are supported by the service
   are listed under <supported> element and all duplex modes that are
   not supported by the service are listed under <notsupported> element.




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   Possible duplex values as defined in RFC3840 are: full, half,
   receive-only, and send-only.


3.2.13  <description> element


   The <description> element provides a textual description of the
   service as defined in RFC3840 [6].


   The <description> element is of string type and does not have any
   attributes.


3.2.14  <event-packages> element


   The <event-packages> element lists the event packages supported by a
   service.


   The <event-packages> element can contain two elements: <supported>
   and <notsupported>.  All event packages that are supported by the
   service are listed under <supported> element and all event packages
   that are not supported by the service are listed under <notsupported>
   element.


   The values for this tag equal the event package names that are
   registered by each event package as defined in RFC3265 [15].  This
   memo defines following values: presence, message-summary, reg, refer,
   winfo, spirits-user-prof, spirits-user-prof, spirits-INDPs, and
   Siemens-RTP-Stats.


3.2.15  <priority> element


   The <priority> element indicates the call priorities the service is
   willing to handle.  A value of X means that the service is willing to
   take requests with priority X and higher as defined in RFC3840 [6].


   The <priority> element is of integer type and does not have any
   attributes.


3.2.16  <methods> element


   The <methods> element indicates the SIP methods supported by a
   service.  In this case, "supported" means that the service can
   receive requests with this method.  In that sense, it has the same
   connotation as the Allow header field as defined in RFC3840 [6].


   The <methods> element can contain two elements: <supported> and
   <notsupported>.  All methods that are supported by the service are
   listed under <supported> element and all methods that are not
   supported by the service are listed under <notsupported> element.




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   The values for this tag equal the method names that are registered by
   each method definition as defined in RFC3261 [14].  This memo defines
   following values: ACK, BYE, CANCEL, INFO, INVITE, MESSAGE, NOTIFY,
   OPTIONS, PRACK, PUBLISH, REFER, REGISTER, SUBSCRIBE, and UPDATE.


3.2.17  <extensions> element


   The <extensions> element is a list of SIP extensions (each of which
   is defined by an option-tag registered with IANA) that are understood
   by the service.  Understood, in this context, means that the option
   tag would be included in a Supported header field in a request as
   defined in RFC3840 [6].


   The <extensions> element can contain two elements: <supported> and
   <notsupported>.  All extensions that are supported by the service are
   listed under <supported> element and all extensions that are not
   supported by the service are listed under <notsupported> element.


   The values for this tag equal the extension names that are registered
   by each extension definition as defined in RFC3261 [14].  This memo
   defines following values: 100rel, join, path, precondition, pref,
   privacy, replaces, and sec-agree.


3.2.18  <schemes> element


   The <schemes> element provides the set of URI schemes that are
   supported by a service.  Supported implies, for example, that the
   service would know how to handle a URI of that scheme in the Contact
   header field of a redirect response as defined in [6].


   The <schemes> element can contain two elements: <supported> and
   <notsupported>.  All schemes that are supported by the service are
   listed under <supported> element and all schemes that are not
   supported by the service are listed under <notsupported> element.


   The values for this tag equal the scheme names that are registered by
   each scheme definition as defined in RFC2396 [22].  This memo defines
   following values: ftp, http, gopher, mailto, news, nntp, telnet,
   wais, file, prospero, z39.50s, z39.50r, cid, mid, vemmi, service,
   imap, nfs, acap, rtsp, tip, pop, data, dav, opaquelocktoken, sip,
   sips, tel, fax, modem, ldap, https, soap.beep, soap.beeps, urn, go,
   h323, ipp, tftp, mudupdate, pres, and im.


3.2.19  <actor> element


   The <actor> element indicates the type of entity that is available at
   this URI as defined in RFC3840 [6].





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   The <actor> element can contain two elements: <supported> and
   <notsupported>.  All actor types that are supported by the service
   are listed under <supported> element and all actor types that are not
   supported by the service are listed under <notsupported> element.


   Possible class values as defined in RFC3840 [6] are:


   o  <principal>: The service provides communication with the principal
      that is associated with the service.  Often this will be a
      specific human being, but it can be an automata (for example, when
      calling a voice portal).


   o  <attendant>: The service provides communication with an automata
      or person that will act as an intermediary in contacting the
      principal associated with the service, or a substitute.


   o  <msg-taker>: The service provides communication with an automata
      or person that will take messages and deliver them to the
      principal.


   o  <information>: The service provides communication with an automata
      or person that will provide information about the principal.



3.2.20  <isfocus> element


   The <isfocus> element indicates that the service is a conference
   server, also known as a focus as defined in RFC3840 [6].


   The <isfocus> element is of boolean type and does not have any
   attributes.


3.2.21  <languages> element


   The <languages> element indicates the ability to display particular
   human languages as defined in RFC2987 [8].


   The <languages> element can contain two elements: <supported> and
   <notsupported>.  All languages that are supported by the service are
   listed under <supported> element and all languages that are not
   supported by the service are listed under <notsupported> element.


   <supported> and <notsupported> elements can contain any number of <l>
   elements which can be used to describe individual languages supported
   by the service.







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3.2.21.1  <l> element


   The <l> element is of string type and it is used to describe
   individual language supported by the service.  Values that can be
   used here are language names that are registered to IANA as per
   RFC2987 [8].


3.3  Device capability document


   Elements belonging to this document are used to describe dynamic
   status of a device [11].  This document SHOULD be located in PIDF
   document as a child element of urn:ietf:params:xml:ns:pidf:device
   namespace <status> element [11].


   Namespace identifier for this document is
   urn:ietf:params:xml:ns:pidf:status:devcaps.


3.3.1  <devcaps> element


   The root element of the device capability document is <devcaps>.  The
   root element has to be always present.  This element can contain one
   or more elements as specified later in this document.


   A <devcaps> element does not have any attributes and it can contain
   other namespace declarations for the extensions used in the presence
   XML document.


3.3.2  <mobility> element


   The <mobility> element indicates whether the device is fixed (meaning
   that it is associated with a fixed point of contact with the
   network), or mobile (meaning that it is not associated with a fixed
   point or contact).  Note that cordless phones are fixed, not mobile,
   based on this definition as defined in RFC3840 [6].


   The <mobility> element can contain two elements: <supported> and
   <notsupported>.  All mobility modes that are supported by the device
   are listed under <supported> element and all mobility modes that are
   not supported by the device are listed under <notsupported> element.


   This memo defines two values that are defined in RFC3840 [6]: <fixed>
   and <mobile>.


3.3.3  <priority> element


   The <priority> element indicates the call priorities the device is
   willing to handle.  A value of X means that the device is willing to
   take requests with priority X and higher as defined in RFC3840 [6].




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   The <priority> element is of integer type and does not have any
   attributes.


3.3.4  <description> element


   The <description> element provides a textual description of the
   device as defined in RFC3840 [6].


   The <description> element is of string type and does not have any
   attributes.


4.  Usage guidelines


   In RFC3840 [6] it is recommended that a UA provides complete
   information in its contact predicate.  However, it may be that
   presentity is not willing to publish presence information which would
   be consistent with actual device or service capabilities (e.g.
   presentity may not want to indicate that he/she supports voice when
   the service actually is able to support it).  Also authorization
   rules or policies in presence server may limit or modify the
   published presence information in a way that all published presence
   information may not end up to all possible watchers.


   It is RECOMMENTED that Presence User Agents (PUAs) using this
   extension provide as complete presence information as they can.
   However, it is not mandated that this presence information should be
   consistent with actual device capabilities.  Also, watchers should
   not expect that the presence information represented by this
   extension fully represents the actual presentity's device
   capabilities.


5.  Examples


5.1  Example


   <?xml version="1.0" encoding="UTF-8"?>
   <presence xmlns="urn:ietf:params:xml:ns:pidf"
   xmlns:sc="urn:ietf:params:xml:ns:pidf:status:servcaps"
   xmlns:dc="urn:ietf:params:xml:ns:pidf:status:devcaps"
   xmlns:dev="urn:ietf:params:xml:ns:pidf:device"
   entity="pres:someone@example.com">


     <tuple id="joi9877866786ua9">
       <status>
         <basic>open</basic>
       </status>
       <sc:servcaps>
         <sc:audio>true</sc:audio>




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         <sc:video>false</sc:video>
         <sc:message>true</sc:message>
         <sc:duplex>
           <sc:supported>
             <sc:full/>
           </sc:supported>
         </sc:duplex>
         <sc:description>
           Example service
         </sc:description>
         <sc:methods>
           <sc:supported>
             <sc:INVITE/>
             <sc:ACK/>
             <sc:BYE/>
           </sc:supported>
         </sc:methods>
       </sc:servcaps>
       <contact>sip:someone@example.com</contact>
     </tuple>
     <dev:device id="jv3095qj1jv8a">
       <dev:status>
         <dc:devcaps>
           <dc:mobility>
             <dc:supported>
               <dc:mobile/>
             </dc:supported>
           </dc:mobility>
           <dc:priority>10</dc:priority>
         </dc:devcaps>
       </dev:status>
     </dev:device>
   </presence>



6.  XML schema definitions


   This section gives the XML schema definitions for the extensions
   defined in this document.


6.1  Service capability document


   This section gives the XML schema definition for service XML
   document.  Namespace identifier for this schema is
   urn:ietf:params:xml:ns:pidf:status:servcaps.


   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema targetNamespace="urn:ietf:params:xml:ns:pidf:servcaps"




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   xmlns:xs="http://www.w3.org/2001/XMLSchema"
   xmlns:tns="urn:ietf:params:xml:ns:pidf:servcaps"
   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/xml.xsd"/>


     <!-- ROOT -->
       <xs:element name="servcaps" type="tns:servcapstype"/>
        <xs:complexType name="servcapstype">
          <xs:sequence>
           <xs:element name="audio"
             type="tns:audiotype" minOccurs="0"/>
           <xs:element name="application"
             type="tns:applicationtype" minOccurs="0"/>
           <xs:element name="data"
             type="tns:datatype" minOccurs="0"/>
           <xs:element name="control"
             type="tns:controltype" minOccurs="0"/>
           <xs:element name="video"
             type="tns:videotype" minOccurs="0"/>
           <xs:element name="text"
             type="tns:texttype" minOccurs="0"/>
           <xs:element name="message"
             type="tns:messagetype" minOccurs="0"/>
           <xs:element name="type"
             type="tns:typetype" minOccurs="0"
             maxOccurs="unbounded"/>
           <xs:element name="automata"
             type="tns:automatatype" minOccurs="0"/>
           <xs:element name="class"
             type="tns:classtype" minOccurs="0"/>
           <xs:element name="duplex"
             type="tns:duplextype" minOccurs="0"/>
           <xs:element name="description"
             type="tns:descriptiontype" minOccurs="0"/>
           <xs:element name="event-packages"
             type="tns:event-packagestype" minOccurs="0"/>
           <xs:element name="priority"
             type="tns:prioritytype" minOccurs="0"/>
           <xs:element name="methods"
             type="tns:methodstype" minOccurs="0"/>
           <xs:element name="extensions"
             type="tns:extensionstype" minOccurs="0"/>
           <xs:element name="schemes"




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             type="tns:schemestype" minOccurs="0"/>
           <xs:element name="actor"
             type="tns:actortype" minOccurs="0"/>
           <xs:element name="isfocus"
             type="tns:isfocustype" minOccurs="0"/>
           <xs:element name="languages"
             type="tns:languagestype" minOccurs="0"/>
           <xs:any namespace="##other"
             processContents="lax" minOccurs="0"
             maxOccurs="unbounded"/>
         </xs:sequence>
       </xs:complexType>


       <!-- AUDIO -->
       <xs:simpleType name="audiotype">
          <xs:restriction base="xs:boolean"/>
       </xs:simpleType>


       <!-- APPLICATION -->
       <xs:simpleType name="applicationtype">
          <xs:restriction base="xs:boolean"/>
       </xs:simpleType>


       <!-- DATA -->
       <xs:simpleType name="datatype">
         <xs:restriction base="xs:boolean"/>
       </xs:simpleType>


       <!-- CONTROL -->
       <xs:simpleType name="controltype">
         <xs:restriction base="xs:boolean"/>
       </xs:simpleType>


       <!-- VIDEO -->
       <xs:simpleType name="videotype">
         <xs:restriction base="xs:boolean"/>
       </xs:simpleType>


       <!-- TEXT -->
       <xs:simpleType name="texttype">
         <xs:restriction base="xs:boolean"/>
       </xs:simpleType>


       <!-- MESSAGE -->
       <xs:simpleType name="messagetype">
         <xs:restriction base="xs:boolean"/>
       </xs:simpleType>





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       <!-- TYPE -->
       <xs:simpleType name="typetype">
         <xs:restriction base="xs:string"/>
       </xs:simpleType>


       <!-- AUTOMATA -->
       <xs:simpleType name="automatatype">
         <xs:restriction base="xs:boolean"/>
       </xs:simpleType>


       <!-- CLASS -->
      <xs:complexType name="classtype">
        <xs:sequence>
          <xs:element name="supported" minOccurs="0">
            <xs:complexType>
              <xs:sequence>
                <xs:element
                ref="tns:classtypes"
                maxOccurs="unbounded"/>
              </xs:sequence>
            </xs:complexType>
          </xs:element>
          <xs:element name="notsupported" minOccurs="0">
            <xs:complexType>
              <xs:sequence>
                <xs:element
                ref="tns:classtypes"
                maxOccurs="unbounded"/>
              </xs:sequence>
            </xs:complexType>
          </xs:element>
         </xs:sequence>
       </xs:complexType>
     <xs:element name="classtypes" abstract="true"/>
     <xs:element name="personal" substitutionGroup="tns:classtypes"/>
     <xs:element name="business" substitutionGroup="tns:classtypes"/>


     <!-- DUPLEX -->
     <xs:complexType name="duplextype">
       <xs:sequence>
       <xs:element name="supported" minOccurs="0">
         <xs:complexType>
           <xs:sequence>
             <xs:element
             ref="tns:duplextypes"
             maxOccurs="unbounded"/>
           </xs:sequence>
         </xs:complexType>




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       </xs:element>
       <xs:element name="notsupported" minOccurs="0">
         <xs:complexType>
           <xs:sequence>
             <xs:element
              ref="tns:duplextypes"
              maxOccurs="unbounded"/>
           </xs:sequence>
         </xs:complexType>
       </xs:element>
      </xs:sequence>
     </xs:complexType>
     <xs:element name="duplextypes" abstract="true"/>
     <xs:element name="full" substitutionGroup="tns:duplextypes"/>
     <xs:element name="half" substitutionGroup="tns:duplextypes"/>
     <xs:element name="receive-only"
       substitutionGroup="tns:duplextypes"/>
     <xs:element name="send-only"
       substitutionGroup="tns:duplextypes"/>


     <!-- DESCRIPTION -->
     <xs:simpleType name="descriptiontype">
       <xs:restriction base="xs:string"/>
     </xs:simpleType>


     <!-- EVENT-PACKAGES -->
     <xs:complexType name="event-packagestype">
       <xs:sequence>
         <xs:element name="supported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:eventpackagetypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
         <xs:element name="notsupported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:eventpackagetypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
       </xs:sequence>
     </xs:complexType>




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     <xs:element name="eventpackagetypes" abstract="true"/>
     <xs:element name="presence"
       substitutionGroup="tns:eventpackagetypes"/>
     <xs:element name="message-summary"
       substitutionGroup="tns:eventpackagetypes"/>
     <xs:element name="reg"
       substitutionGroup="tns:eventpackagetypes"/>
     <xs:element name="refer"
       substitutionGroup="tns:eventpackagetypes"/>
     <xs:element name="winfo"
       substitutionGroup="tns:eventpackagetypes"/>
     <xs:element name="spirits-user-prof"
       substitutionGroup="tns:eventpackagetypes"/>
     <xs:element name="spirits-INDPs"
       substitutionGroup="tns:eventpackagetypes"/>
     <xs:element name="Siemens-RTP-Stats"
       substitutionGroup="tns:eventpackagetypes"/>


     <!-- PRIORITY -->
     <xs:simpleType name="prioritytype">
       <xs:restriction base="xs:integer"/>
     </xs:simpleType>


     <!-- METHODS -->
     <xs:complexType name="methodstype">
       <xs:sequence>
         <xs:element name="supported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:methodtypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
         <xs:element name="notsupported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:methodtypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
       </xs:sequence>
     </xs:complexType>
     <xs:element name="methodtypes" abstract="true"/>
     <xs:element name="ACK" substitutionGroup="tns:methodtypes"/>




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     <xs:element name="BYE" substitutionGroup="tns:methodtypes"/>
     <xs:element name="CANCEL" substitutionGroup="tns:methodtypes"/>
     <xs:element name="INFO" substitutionGroup="tns:methodtypes"/>
     <xs:element name="INVITE" substitutionGroup="tns:methodtypes"/>
     <xs:element name="MESSAGE" substitutionGroup="tns:methodtypes"/>
     <xs:element name="NOTIFY" substitutionGroup="tns:methodtypes"/>
     <xs:element name="OPTIONS" substitutionGroup="tns:methodtypes"/>
     <xs:element name="PRACK" substitutionGroup="tns:methodtypes"/>
     <xs:element name="PUBLISH" substitutionGroup="tns:methodtypes"/>
     <xs:element name="REFER" substitutionGroup="tns:methodtypes"/>
     <xs:element name="REGISTER" substitutionGroup="tns:methodtypes"/>
     <xs:element name="SUBSCRIBE" substitutionGroup="tns:methodtypes"/>
     <xs:element name="UPDATE" substitutionGroup="tns:methodtypes"/>


     <!-- EXTENSIONS -->
     <xs:complexType name="extensionstype">
       <xs:sequence>
         <xs:element name="supported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:extensiontypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
         <xs:element name="notsupported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:extensiontypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
       </xs:sequence>
     </xs:complexType>
     <xs:element name="extensiontypes" abstract="true"/>
     <xs:element name="100rel" substitutionGroup="tns:extensiontypes"/>
     <xs:element name="join" substitutionGroup="tns:extensiontypes"/>
     <xs:element name="path" substitutionGroup="tns:extensiontypes"/>
     <xs:element name="precondition"
       substitutionGroup="tns:extensiontypes"/>
     <xs:element name="pref" substitutionGroup="tns:extensiontypes"/>
     <xs:element name="privacy" substitutionGroup="tns:extensiontypes"/>
     <xs:element name="replaces"
       substitutionGroup="tns:extensiontypes"/>
     <xs:element name="sec-agree"




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       substitutionGroup="tns:extensiontypes"/>


     <!-- SCHEMES -->
     <xs:complexType name="schemestype">
       <xs:sequence>
         <xs:element name="supported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:schemetypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
         <xs:element name="notsupported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:schemetypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
       </xs:sequence>
     </xs:complexType>
     <xs:element name="schemetypes" abstract="true"/>
     <xs:element name="ftp" substitutionGroup="tns:schemetypes"/>
     <xs:element name="http" substitutionGroup="tns:schemetypes"/>
     <xs:element name="gopher" substitutionGroup="tns:schemetypes"/>
     <xs:element name="mailto" substitutionGroup="tns:schemetypes"/>
     <xs:element name="news" substitutionGroup="tns:schemetypes"/>
     <xs:element name="nntp" substitutionGroup="tns:schemetypes"/>
     <xs:element name="telnet" substitutionGroup="tns:schemetypes"/>
     <xs:element name="wais" substitutionGroup="tns:schemetypes"/>
     <xs:element name="file" substitutionGroup="tns:schemetypes"/>
     <xs:element name="prospero" substitutionGroup="tns:schemetypes"/>
     <xs:element name="z39.50s" substitutionGroup="tns:schemetypes"/>
     <xs:element name="z39.50r" substitutionGroup="tns:schemetypes"/>
     <xs:element name="cid" substitutionGroup="tns:schemetypes"/>
     <xs:element name="mid" substitutionGroup="tns:schemetypes"/>
     <xs:element name="vemmi" substitutionGroup="tns:schemetypes"/>
     <xs:element name="service" substitutionGroup="tns:schemetypes"/>
     <xs:element name="imap" substitutionGroup="tns:schemetypes"/>
     <xs:element name="nfs" substitutionGroup="tns:schemetypes"/>
     <xs:element name="acap" substitutionGroup="tns:schemetypes"/>
     <xs:element name="rtsp" substitutionGroup="tns:schemetypes"/>
     <xs:element name="tip" substitutionGroup="tns:schemetypes"/>
     <xs:element name="pop" substitutionGroup="tns:schemetypes"/>




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     <xs:element name="data" substitutionGroup="tns:schemetypes"/>
     <xs:element name="dav" substitutionGroup="tns:schemetypes"/>
     <xs:element name="opaquelocktoken"
       substitutionGroup="tns:schemetypes"/>
     <xs:element name="sip" substitutionGroup="tns:schemetypes"/>
     <xs:element name="sips" substitutionGroup="tns:schemetypes"/>
     <xs:element name="tel" substitutionGroup="tns:schemetypes"/>
     <xs:element name="fax" substitutionGroup="tns:schemetypes"/>
     <xs:element name="modem" substitutionGroup="tns:schemetypes"/>
     <xs:element name="ldap" substitutionGroup="tns:schemetypes"/>
     <xs:element name="https" substitutionGroup="tns:schemetypes"/>
     <xs:element name="soap.beep"
       substitutionGroup="tns:schemetypes"/>
     <xs:element name="soap.beeps"
       substitutionGroup="tns:schemetypes"/>
     <xs:element name="urn" substitutionGroup="tns:schemetypes"/>
     <xs:element name="go" substitutionGroup="tns:schemetypes"/>
     <xs:element name="h323" substitutionGroup="tns:schemetypes"/>
     <xs:element name="ipp" substitutionGroup="tns:schemetypes"/>
     <xs:element name="tftp" substitutionGroup="tns:schemetypes"/>
     <xs:element name="mudupdate" substitutionGroup="tns:schemetypes"/>
     <xs:element name="pres" substitutionGroup="tns:schemetypes"/>
     <xs:element name="im" substitutionGroup="tns:schemetypes"/>


     <!-- ACTOR -->
     <xs:complexType name="actortype">
       <xs:sequence>
         <xs:element name="supported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:actortypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
         <xs:element name="notsupported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               ref="tns:actortypes"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
       </xs:sequence>
     </xs:complexType>
     <xs:element name="actortypes" abstract="true"/>




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     <xs:element name="principal" substitutionGroup="tns:actortypes"/>
     <xs:element name="attendant" substitutionGroup="tns:actortypes"/>
     <xs:element name="msg-taker" substitutionGroup="tns:actortypes"/>
     <xs:element name="information"
       substitutionGroup="tns:actortypes"/>


     <!-- ISFOCUS -->
     <xs:simpleType name="isfocustype">
       <xs:restriction base="xs:boolean"/>
     </xs:simpleType>


     <!-- LANGUAGES -->
     <xs:complexType name="languagestype">
       <xs:sequence>
         <xs:element name="supported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               name="l" type="xs:string"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
         <xs:element name="notsupported" minOccurs="0">
           <xs:complexType>
             <xs:sequence>
               <xs:element
               name="l" type="xs:string"
               maxOccurs="unbounded"/>
             </xs:sequence>
           </xs:complexType>
         </xs:element>
       </xs:sequence>
     </xs:complexType>
   </xs:schema>




                                Figure 2



6.2  Device capability document


   This section gives the XML schema definition for device XML document.
   Namespace identifier for this schema is
   urn:ietf:params:xml:ns:pidf:status:devcaps.


   <?xml version="1.0" encoding="UTF-8"?>




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   <xs:schema
     targetNamespace="urn:ietf:params:xml:ns:pidf:status:devcaps"
   xmlns:xs="http://www.w3.org/2001/XMLSchema"
   xmlns:tns="urn:ietf:params:xml:ns:pidf:status:devcaps"
   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/xml.xsd"/>


     <!-- ROOT -->
     <xs:element name="devcaps" type="tns:devcaps"/>
     <xs:complexType name="devcaps">
       <xs:sequence>
         <xs:element name="mobility" type="tns:mobilitytype" minOccurs="0"/>
         <xs:element name="description" type="tns:descriptiontype"
         minOccurs="0"/>
         <xs:element name="priority" type="tns:prioritytype" minOccurs="0"/>
         <xs:any namespace="##other" processContents="lax"
         minOccurs="0" maxOccurs="unbounded"/>
       </xs:sequence>
     </xs:complexType>


     <!-- MOBILITY -->
     <xs:complexType name="mobilitytype">
       <xs:sequence>
       <xs:element name="supported" minOccurs="0">
         <xs:complexType>
         <xs:sequence>
           <xs:element ref="tns:mobilitytypes" maxOccurs="unbounded"/>
         </xs:sequence>
         </xs:complexType>
       </xs:element>
       <xs:element name="notsupported" minOccurs="0">
         <xs:complexType>
           <xs:sequence>
           <xs:element ref="tns:mobilitytypes" maxOccurs="unbounded"/>
         </xs:sequence>
         </xs:complexType>
         </xs:element>
       </xs:sequence>
     </xs:complexType>
     <xs:element name="mobilitytypes" abstract="true"/>
     <xs:element name="fixed" substitutionGroup="tns:mobilitytypes"/>
     <xs:element name="mobile" substitutionGroup="tns:mobilitytypes"/>





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     <!-- DESCTIPTION -->
     <xs:simpleType name="descriptiontype">
       <xs:restriction base="xs:string"/>
     </xs:simpleType>


     <!-- PRIORITY -->
     <xs:simpleType name="prioritytype">
          <xs:restriction base="xs:integer"/>
     </xs:simpleType>
   </xs:schema>




                                Figure 3



7.  IANA Considerations


   This memo calls for IANA to register two new XML namespace URNs as
   defined in RFC3688 [10].


7.1   URN sub-namespace registration for
    'urn:ietf:params:xml:ns:pidf:servcaps'


   URI:
   urn:ietf:params:xml:ns:pidf:status:servcaps


   Description:
   This is the XML namespace for XML elements defined by [[[RFCXXXX]]]
   to describe service specific features defined in RFC3840 in
   application/pidf+xml content type.


   Registrant Contact:
   IETF, SIMPLE working group, <simple@ietf.org>
   Mikko Lonnfors, <mikko.lonnfors@nokia.com>


   XML:















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   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>Namespace for PIDF service capability extension</title>
   </head>
   <body>
       <h1>Namespace for PIDF service capability extension</h1>
       <h2>urn:ietf:params:xml:ns:pidf:status:servcaps</h2>
       <p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>
    </body>
    </html>
   END



7.2   URN sub-namespace registration for
    'urn:ietf:params:xml:ns:pidf:status:devcaps'


   URI:
   urn:ietf:params:xml:ns:pidf:status:devcaps


   Description:
   This is the XML namespace for XML elements defined by [[[RFCXXXX]]]
   to describe device specific features defined in RFC3840 in
   application/pidf+xml content type.


   Registrant Contact:
   IETF, SIMPLE working group, <simple@ietf.org>
   Mikko Lonnfors, <mikko.lonnfors@nokia.com>


   XML:

















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   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>Namespace for PIDF device capability extension</title>
   </head>
   <body>
       <h1>Namespace for PIDF device capability extension</h1>
       <h2>urn:ietf:params:xml:ns:pidf:status:devcaps</h2>
       <p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>
    </body>
    </html>
   END



8.  Security Considerations


   All security considerations specified in RFC3859 [5] and in RFC3863
   [4] apply to this document.  Compared to PIDF [4] this presence
   document format may reveal additional information about user's
   service and device capabilities.


   Because presence is very privacy-sensitive information, the transport
   protocol for the presence information SHOULD have capabilities to
   protect protocol messages from possible threats, such as
   eavesdropping, corruption, tamper and replay attacks.  The protocols
   SHOULD be able to use security mechanisms which are standardized or
   being standardized in IETF.  However, it depends on the actual
   transport protocols which security mechanisms should be used, and it
   is beyond the scope of this memo.


9.  Acknowledgments


   Authors of this document would like to thank following people for
   their contributions and valuable comments: Paul Kyzivat, Jonathan
   Rosenberg, Markus Isomaki, Eva Leppanen, Miguel Garcia, and Hisham
   Khartabil.


10.  References


10.1  Normative references


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




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


   [3]   Day, M., Aggarwal, S., Mohr, G. and J. Vincent, "Instant
         Messaging / Presence Protocol Requirements", RFC 2779, February
         2000.


   [4]   Sugano, H., Fujimoto, S., Klyne, G., Bateman, A., Carr, W. and
         J. Peterson, "Presence Information Data Format (PIDF)", RFC
         3863, August 2004.


   [5]   Peterson, J., "Common Profile for Presence (CPP)", RFC 3859,
         August 2004.


   [6]   Schulzrinne, H., Rosenberg, J. and P. Kyzivat, "Indicating User
         Agent Capabilities in the Session Initiation Protocol (SIP)",
         RFC 3840, August 2004.


   [7]   Klyne, G., "MIME Content Types in Media Feature Expressions",
         RFC 2913, September 2000.


   [8]   Hoffman, P., "Registration of Charset and Languages Media
         Features Tags", RFC 2987, November 2000.


   [9]   Moats, R., "A URN namespace for IETF documents", RFC 2648, Aug.
         1999.


   [10]  Mealling, M., "The IETF XML Registry", RFC 3688, BCP 81,
         January 2004.


   [11]  Rosenberg, J., "A Data Model for Presence",
         draft-ietf-simple-presence-data-model-00 (work in progres),
         September 2004.


10.2  Informative references


   [12]  Schulzrinne, H., Rosenberg, J. and P. Kyzivat, "Caller
         Preferences for the Session Initiation Protocol (SIP)", RFC
         3841, August 2004.


   [13]  Peterson, J., "Common Profile for Instant Messaging (CPIM)",
         RFC 3860, August 2004.


   [14]  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.


   [15]  Roach, A., "Session Initiation Protocol (SIP)-Specific Event




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         Notification", RFC 3265, June 2002.


   [16]  Rosenberg, J., "Session Initiation Protocol (SIP) Extensions
         for Presence", RFC 3856, August 2004.


   [17]  Handley, M. and V. Jacobson, "SDP: Session Description
         Protocol", RFC 2327, April 1998.


   [18]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
         Extensions (MIME) part two: Media Types", RFC 2046, November
         1996.


   [19]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
         Extensions (MIME) part one:Format of Internet Message Bodies",
         RFC 2045, November 1996.


   [20]  Alvestrand, H., "Tags for the Identification of Languages", RFC
         1766, March 1995.


   [21]  Holtman, K., Mutz, A. and T. Hardie, "Media Feature Tag
         Registration Procedure", RFC 2506, March 1999.


   [22]  Berners-Lee, T., Fielding, R. and L. Masinter, "Uniform
         Resource Identifiers (URI): Generic Syntax", RFC 2296, August
         1998.



Authors' Addresses


   Mikko Lonnfors
   Nokia
   Itamerenkatu 11-13 00180
   Helsinki
   Finland


   Phone: +358 71 8008000
   EMail: mikko.lonnfors@nokia.com



   Krisztian Kiss
   Nokia
   12278 Scripps Summit Drive
   San Diego
   US


   Phone: +18582049141
   EMail: krisztian.kiss@nokia.com





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