Internet Engineering Task Force
Internet Draft                                      H. Schulzrinne (ed.)
                                                             Columbia U.
June 29, 2003
Expires: December 2003

   RPIDS -- Rich Presence Information Data Format for Presence Based
                on the Session Initiation Protocol (SIP)


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

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   The Rich Presence Information Data Format for the Session Initiation
   Protocol (SIP) (RPIDS) adds elements to the Presence Information Data
   Format (PIDF) that provide additional information about the
   presentity and its contacts. This information can be translated into
   call routing behavior or be delivered to watchers. The information is
   designed so that much of it can be derived automatically, e.g., from
   calendar files or user activity.

1 Introduction

   The PIDF definition [1] describes a basic presence information data
   format for exchanging presence information in CPIM-compliant systems.
   It consists of a <presence> root element, zero or more <tuple>
   elements carrying presence information, zero or more <note> elements
   and zero or more extension elements from other name spaces.  Each
   tuple defines a basic status of either "open" or "closed".
This document provides additional status information for presentities
   and defines a Rich Presence Information Data Format for Presence
   Based on the Session Initiation Protocol (SIP) (RPIDS) to convey this

   This extension has three main goals:

        1.   Provide rich presence indication that is at least as
             powerful as common commercial presence systems. Such
             feature-parity simplifies transition to CPIM-compliant
             systems, both in terms of user acceptance and protocol

        2.   Maintain backwards-compatibility with PIDF, so that PIDF-
             only watchers and gateways can continue to function
             properly, naturally without access to the functionality
             described here.

   We make no assumptions how the information in the RPIDS is generated.
   Experience has shown that users are not always diligent about
   updating their presence status. Thus, we want to make it as easy as
   possible to derive RPIDS information from other information sources,
   such as calendars, the status of communication devices such as
   telephones, typing activity and physical presence detectors as
   commonly found in energy-management systems.

   The information in a presence document can be generated by a single
   entity or can be composed from information published by multiple

   Many of the elements correspond to data commonly found in personal
   calendars. Thus, we attempted to align some of the extensions with
   the usage found in calendar formats such as iCal [12] and xCal [13],
   as noted below.

   Note that PIDF documents and this extension can be used in two
   different contexts, namely by the presentity to publish its presence
   status and by the presence server to notify some set of watchers. The
   presence server MAY compose, translate or filter the published
   presence state before delivering customized presence information to
   the watcher. For example, it may merge presence information from
   multiple PUAs, remove whole elements, translate values in elements or
   remove information from elements. Mechanisms that filter calls and
   other communications to the presentity can subscribe to this presence
   information just like a regular watcher and in turn generate
   automated rules, such as scripts [14], that govern the actual
   communications behavior of the presentity.

   The flow diagram below illustrates this process.

      --> publish
            --> PA (filter)
                    --> notification 1 to A, B, C
                    --> notification 2 to D, E
                    --> notification 3 to F
                    --> notification 4 to script gen.

2 RPIDS Features

   Below, we summarize and motivate the major additional features that
   RPIDS adds to PIDF.

   The PIDF definition does not clearly describe what a <tuple>
   represents. We add an <class> attribute (Section 6.4) that allows a
   presentity to label tuples in ways that make sense to the presentity,
   e.g., to group similar tuples by name.

   While the PIDF definition describes which means of communications are
   available for a presentity, it does not describe the activity that
   the presentity is currently engaged in. The <activity> (Section 6.2)
   element adds this information.

   The <idle> (Section 6.7) element indicates when the device was last
   used or simply whether it has been idle.

   To help the watcher gauge the appropriateness of different types of
   communications, we indicate the type of place the user is currently
   in, via the <placetype> element (Section 6.9) and hint at the privacy
   available via <privacy>.

   PIDF defines a <timestamp> element indicating the date and time of
   the status change of a tuple. RPIDS adds a validity period for status
   values, <from> and <until>, as a hint how long the current status is
   likely to be valid (Section 6.5 and Section 6.13).

   Information about a tuple can be conveyed using the <card>, <info>
   and <icon> elements.

   An important sub-case is that a presentity is interruptible only
   under unusual circumstances, after mediation replaced by some, typically
   human, authority such as a secretary or supervisor. We allow the
   presentity to convey that certain contact addresses actually belong
   to a different person, presumably one that can either interrupt the
   presentity or otherwise assist. The <relationship> (Section 6.11)
   element allows to indicate that a particular tuple refers to a
   different principal or presentity.

   The PIDF document format [1] 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 [3]. The <contact> element is defined to be an URI. This
   URI can be of any URI scheme. Some URI schemes uniquely identify the
   application the tuple intends to describe (e.g., "im" URIs). However,
   this is not be the case for all schemes. draft-ietf-simple-rpid-00.txt
For example, a SIP URI can
   represent different kinds of applications, including voice, video, or
   messaging. If it is not known by other means, it can be hard for
   applications processing the presence document containing only SIP URI
   contact addresses to know what particular application the tuple
   intends to describe. Also, watchers receiving presence information
   would benefit for getting more descriptive information about what
   particular communication means or applications are supported by the

   We generally assume that the presence element describes a single
   human being or a group of humans. However, this is not required. A
   presentity can also be a "bot" or "avatar", for example.

   Note that this document does not defined a new content type. Rather,
   it inherits the content type from [1], namely application/cpim-

3 Scope

   This extension does not replace media negotiation mechanisms defined
   for SIP (e.g. SDP [4]), therefore media negotiation (e.g., choice of
   voice and video codecs) MUST be performed according to [5]. This
   extension is only aimed to give the watchers hints about the
   presentity's preferences, willingness and capabilities to communicate
   before watchers initiate SIP-based communication with the presentity.

4 Terminology and Conventions

   This memo makes use of the vocabulary defined in the IMPP Model
   document [3]. Terms such as CLOSED, INSTANT MESSAGE, OPEN, PRESENCE
   used in the same meaning as defined therein. The key words MUST,
   in this document are to be interpreted as described in BCP XX, RFC
   2119 [6].

5 The Meaning of "open" and "closed"

   PIDF describes the basic status values of "open" or "closed" only as
   "have meanings of general availability for other communications
   means". We define "closed" in our context as meaning that
   communication to the contact address will in all likelihood not
   succeed, is undesired or will not reach the intended party. (For
   example, a presentity may include a hotel phone number as a contact.
   After check-out, the phone number will still ring, but reach the
   chambermaid or the next guest. Thus, it would be declared "closed".)
   For "pres" contacts, "closed" means that no presence status
   information is available.

        The interpretation copy of "closed" was chosen since there is no
        other status value to indicate that a communications
        address is not reachable. Omitting the <contact> element
        does not work since it would confuse watchers that have not
        previously seen an "open" status for the same document, contact

6 RPIDS Elements

6.1 Introduction

   Below, we describe the RPIDS elements in detail.  <activity>, <card>
   <category>, <class>, <from>, <icon> <idle> <info> <label>,
   <placetype>, <privacy>, <relationship>, <timed-status>, <until>
   extend <status>.

   In general, it is highly unlikely that a presentity will publish or
   announce all of these elements at the same time. Rather, these
   elements were chosen to give the presentity maximum flexibility in
   deriving this information from existing sources, such as calendaring
   tools, device activity sensors or location trackers, as well as to
   manually configure this information.

   The namespace URI for elements defined by this specification is a URN
   [7], using the namespace identifier 'ietf' defined by [8] and
   extended by [9]:


6.2 Activity Element

   The <activity> indication describes what the presentity is currently
   doing. This can be quite helpful to the watcher in judging how
   appropriate a communication attempt is and which means of
   communications is most likely to succeed and not annoy the
   presentity.  The activity indications correspond roughly to the
   category field in calendar entries, such as Section of RFC
   2445 [9].

        Use of an enumerated, but extensible, set of activity
        categories simplifies automated generation and processing
        of presence information. The categories can be readily
        selected from a drop-down list by the user or translated
        from the corresponding activity field in calendars.
        Recipients of this information can render at least a subset
        as icons, automatically translate them into different
        languages or convert them to sound "jingles" and speech, or
        use them to generate call processing rules.

   An activity indication consists of one or more values drawn from the
   list below, any other token string or IANA-registered values (Section
   10). Communities of interest such as a profession or an organization
   may define additional activity labels for their internal use.

        On-the-phone: The presentity is talking on the telephone. This
             activity is included since it can often be derived

        Away: The presentity is physically away from the device
             location.  This activity was included since it can often be
             derived automatically from security systems, energy
             management systems or entry badge systems.

        Appointment: The presentity has a calendar appointment.

        Holiday: This is a scheduled national or local holiday. This
             information can typically be derived automatically from

        Meal: The presentity is scheduled for a meal. This activity
             category can often be generated automatically from a

        Meeting: This activity category can often be generated
             automatically from a calendar.

        Steering: The presentity is controlling a vehicle, ship or

        In-transit: The presentity is riding in a vehicle, such as a
             car, but not steering.

        Travel: The presentity is on a business or personal trip, but
             not necessarily in-transit. This category can often be
             generated automatically from a calendar.

        Vacation: This activity category can often be generated
             automatically from a calendar.

        Sleeping: This activity category can often be generated
             automatically from a calendar or local time information.

        Busy: User is busy, without further details. This activity
             category would typically be indicated manually.

        Permant-absence: Presentity will not return for the foreseeable
             future, e.g., because it is no longer working for the

6.3 Card

   The <card> element provides a URI pointing to a business card, e.g.,
   in LDIF or vCard format.

6.4 Class

   The 'class' attribute describes the class of the tuple. Multiple
   tuples can have the same class name within a presence document. The
   naming of classes is left to the presentity. The presentity can use
   this information to group similar tuples or to convey information
   that the presence agent can use for filtering.

        The class description is similar in spirit to the 'class'
        attribute of XML elements, used to support Cascading Style

6.5 From Element

   The <from> element indicates how long the current status has been
   valid, expressed as an absolute time.

6.6 Icon

   The <icon> element provides a URI pointing to an image (icon)
   representing the tuple. The watcher MAY use this information to
   represent the tuple.

6.7 Idle Element

   The <idle> records the absolute time and date the communication
   device was last used. This provides an indication as to how likely a
   user is to answer the device. A device that has not been used in a
   while may still be OPEN, but a watcher may choose to first contact a
   device that is both OPEN and not marked as idle.

   The <idle> element can be empty if the presentity wants to indicate
   that the device has not been used for a while, but does not want to
   reveal the precise duration:


   The <idle> SHOULD be included in the presence document if the idle
   time exceeds a user-setable threshold, with a RECOMMENDED default
   value of 10 minutes. Configuration MUST include the option to omit
   the timestamp.

6.8 Info

   The <info> element provides a URI pointing to general information
   about the tuple, e.g., a web page.

6.9 Type of Place Element

   The <placetype> element describes the type of place the presentity is
   currently at. This offers the watcher an indication what kind of
   communication is likely to be appropriate. We define an initial set
   of values below:

        home: The presentity is in a private or residential setting, not
             necessarily the personal residence of the presentity, e.g.,
             including hotel or a friend's home.

        office: The presentity is in a business setting, such as an

        public: The presentity is in a public area such as a shopping
             mall, street, park, public building, train station, airport
             or in public conveyance such as a bus, train, plane or

   This list can be augmented by free-text values or additional IANA-
   registered values (Section 10).

        The placetype element can be used by logic executing on the
        watcher or by a composer to filter, sort and label tuples.
        For example, a composer may have rules that limit the
        publication of "home" tuples to a subset of the watchers.

6.10 Privacy Element

   The <privacy> element indicates whether third parties may be able to
   hear or view parts of the communication.

        public: Others may be able to see or hear the communications.

        private: Inappropriate individuals are not likely to see or hear
             the communications.

        quiet: The presentity is in a place such as a library,
             restaurant, place-of-worship, or theater that discourages
             noise, conversation and other distractions.

   This indication is not limited to voice communications. For example,
   a presentity might label her privacy as "quiet" when giving a talk,
   since it would be inappropriate if an instant message popped up on
   the laptop screen that is being projected for the audience.

        The placetype element can be used by logic executing on the
        watcher or by a composer to filter, sort and label tuples.
        For example, a composer may have rules that limit the
        publication of tuples labeled as "quiet" to a select subset
        of the watchers.

6.11 Relationship Element

   The <relationship> element designates the type of relationship an
   alternate contact has with the presentity. This element is provided
   only if the tuple refers to somebody other than the presentity.

   Relationship values include "family", "associate" (e.g., for a
   colleague), "assistant", "supervisor". Other free-text values and
   additional IANA-registered values (Section 10) can be used as well.

   The <contact> element for tuples labeled with a relationship can
   contain either a communication URI such as "im", "sip"/"sips",
   "h323", "tel" or "mailto", or a presence URI, such as "pres" or

6.12 Timed Status Element

   The <timed-status> element describes status information that is
   either no longer valid or covers some future timeperiod.

        Timed status cannot be expressed with <tuples> elements
        where the period between <status> since PIDF parsers would
        not be able to distinguish current from future or past
        information. It is occasionally useful to represent past
        information since it may be the only known presence
        information; it may give watchers an indication of the
        current status. For example, indicating that the presentity
        was at a meeting that ended an hour ago indicates that the
        presentity is likely in transit at the current time.

6.13 Until Element

   The <until> element indicates how long the current basic status (open
   or closed) is likely to be valid, expressed as an absolute time.

   This indication allows the watcher to make better decisions. For
   example, if a presentity indicates that it is likely to be
   unreachable for an extended period of time, the watcher may decide to
   request assistance from somebody else, rather than waiting for the
   presentity to return.

   Often, the duration of the status information is not known precisely.
   Thus, it is helpful to indicate the precision, here expressed in
   seconds. For example, an absence of "a few hours" can easily be
   expressed as a time some hours into the future, with a precision of
   7200 seconds.

        An absolute time was chosen to simplify integration with
        calendaring applications. This combination appears to be
        sematically cleaner than enumerating various measurement
        units such as "months", "weeks", "days" or "hours".

   Both the <from> and <until> information might be derived from
   calendar information, reflecting the start and end time of an
   activity. (Examples include the Date Time Start and Date Time End
   properties of RFC 2445. For simplicity, RPIDS only supports single
   events, without repetition.)

   Any statements such as anticipated validity are not historical facts
   and are forward-looking statements that involve risks and
   uncertainties; actual results may differ from the forward-looking

7 Examples

7.1 Presentity with Capabilities

   <?xml version="1.0" encoding="UTF-8"?>
      <presence xmlns="urn:ietf:params:xml:ns:cpim-pidf"

        <note>I'm in a boring meeting</note>

        <tuple id="7c8dqui">
          <note>My secretary</note>

        <tuple id="18x765">
          <contact priority="0.8"></contact>


        <tuple id="35bs9r" class="cellphone">
          <contact priority="0.8"></contact>

        <tuple id="8eg92n" class="email">
          <contact priority="1.0"></contact>

8 XML Schema Definitions

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

     <!-- This import brings in the XML language attribute xml:lang-->
         <xs:import namespace=""


       <!-- redefinition of tuple -->
       <complexType name="tuple">
           <extension base="pidf:tuple">
             <xsd:attribute name="class" type="xsd:token"/>

     <xs:element name="placetype" type="xs:token"/>
     <xs:element name="privacy" type="tns:privacy"/>
     <xs:element name="activity" type="xs:token"/>
     <xs:element name="relationship" type="xs:token"/>
     <xs:element name="from" type="tns:fromuntil">
     <xs:element name="until" type="tns:fromuntil">
     <xs:element name="idle" type="xs:dateTime">
     <xs:element name="icon" type="xs:anyURI">
     <xs:element name="card" type="xs:anyURI">
     <xs:element name="info" type="xs:anyURI">

     <xs:element name="timed-status" type="tns:timed-status">

     <xs:simpleType name="privacy">
       <xs:restriction base="xs:string">
          <xs:enumeration value="private"/>
          <xs:enumeration value="public"/>
          <xs:enumeration value="quiet"/>

     <xs:complexType name="fromuntil">
         <xs:extension base="xs:dateTime">

     <xs:complexType name="timed-status">
         <xs:element name="basic" type="pidf:basic" minOccurs="0"/>
         <xs:element name="from" type="tns:fromuntil">
         <xs:element name="until" type="tns:fromuntil">
         <xs:element name="note" type="pidf:note">
         <xs:any namespace="##other" processContents="lax" minOccurs="0"

9 Security Considerations

   The security considerations in [1] apply, as well as [11]. Compared
   to PIDF, this presence document format reveals additional information
   that can be highly sensitive. Beyond traditional security measures to
   protect confidentiality and integrity, systems should offer a means
   to selectively reveal information to particular watchers and to
   inspect the information that is being published, particularly if it
   is generated automatically from other sources, such as calendars or

   Like any information retrieved by reference, the information provided
   in the <card>, <icon> and <info> elements may refer to data types
   that expose the watcher to security risks.

10 IANA Considerations

   This document calls for IANA to:

        o register two new XML namespace URNs per [9];

        o establish registry for activity categories (Section 6.2),
          place types (Section 6.9), and relationships (Section 6.11).

   Note that this document does not need a new content type. It inherits
   the content type from [1], namely application/cpim-pidf+xml

10.1 URN Sub-Namespace Registration for

        URI: urn:ietf:params:xml:ns:sip-rpids

        Description: This is the XML namespace for XML elements defined
             by RFCXXXX to describe a rich presence information
             extension for the CPIM-PIDF presence document format in the


        content type.

        Registrant Contact:  IETF, SIMPLE working group,
             Henning Schulzrinne, <>


                <?xml version="1.0"?>
                <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
                <html xmlns="
                     <meta http-equiv="content-type"
                     <title>RPIDS -- Rich Presence Information Data Format
               for Presence Based on the Session
               Initiation Protocol (SIP)</title>
                    <h1>Namespace for SIMPLE rich presence extension</h1>
                    <p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>

10.2 URN Sub-Namespace Registration for

        URI: urn:ietf:params:xml:ns:sip-prescaps

        Description: This is the XML namespace for XML elements defined
             by RFCXXXX to describe a capabilities presence information
             extension for the CPIM-PIDF presence document format in the


        Registrant Contact:  IETF, SIMPLE working group,
             Henning Schulzrinne, <>


                <?xml version="1.0"?>
                <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
                <html xmlns="
                     <meta http-equiv="content-type"
                     <title>SIMPLE PIDF presence capabilities extension</title>
                    <h1>Namespace for SIMPLE presence capabilities extension</h1>
                    <p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p>

10.3 Place Type, Device Type, Categories, Relationships

   This document creates new IANA registries for categories, device
   types, place types and relationships. All are XML tokens. Registered
   tokens must be documented at the time of registration, as most
   descriptions are expected to be brief.

   The SIMPLE working group, or, if no longer available, the SIP working
   group should be consulted prior to registration.

11 Acknowledgements

   The document reflects the discussion on the SIMPLE mailing list, with
   contributions from many individuals. Markus Isomaki, Hisham
   Khartabil, Jon Peterson and Brian Rosen provided detailed comments
   and suggestions.  The notion of external references in the <card>,
   <icon> and <info> elements is an evolution of the BINPIDF proposal by
   Khartabil et al.

12 References

13 Normative References

   [1] H. Sugano, S. Fujimoto, et al., "Common presence and instant
   messaging (cpim)presence information data format," internet draft,
   Internet Engineering Task Force, Jan. 2003.  Work in progress.

   [2] H. Schulzrinne and J. Rosenberg, "Session initiation protocol
   (SIP) caller preferences and callee capabilities," internet draft,
   Internet Engineering Task Force, Nov. 2002.  Work in progress.

   [3] M. Day, J. Rosenberg, and H. Sugano, "A model for presence and
   instant messaging," RFC 2778, Internet Engineering Task Force, Feb.

   [4] M. Handley and V. Jacobson, "SDP: session description protocol,"
   RFC 2327, Internet Engineering Task Force, Apr. 1998.

   [5] J. Rosenberg and H. Schulzrinne, "An offer/answer model with
   session description protocol (SDP)," RFC 3264, Internet Engineering
   Task Force, June 2002.

   [6] S. Bradner, "Key words for use in rfcs to indicate requirement
   levels," RFC 2119, Internet Engineering Task Force, Mar. 1997.

   [7] R. Moats, "URN syntax," RFC 2141, Internet Engineering Task
   Force, May 1997.

   [8] R. Moats, "A URN namespace for IETF documents," RFC 2648,
   Internet Engineering Task Force, Aug. 1999.

   [9] M. Mealling, "The IETF XML registry," internet draft, Internet
   Engineering Task Force, July 2002.  Work in progress.

   [10] K. Holtman, A. Mutz, and T. Hardie, "Media feature tag
   registration procedure," RFC 2506, Internet Engineering Task Force,
   Mar. 1999.

   [11] J. Rosenberg, "A presence event package for the session
   initiation protocol (SIP)," internet draft, Internet Engineering Task
   Force, Jan. 2003.  Work in progress.

14 Informative References

   [12] F. Dawson and D. Stenerson, "Internet calendaring and scheduling
   core object specification (icalendar)," RFC 2445, Internet
   Engineering Task Force, Nov. 1998.

   [13] F. D. Jr., S. M. Reddy, D. Royer, and E. Plamondon, "icalendar
   DTD document (xcal)," internet draft, Internet Engineering Task
   Force, July 2002.  Work in progress.

   [14] J. Lennox and author directly.

Draft Author(s):

H. Schulzrinne, "CPL: a language for user control
   of Internet telephony services," internet draft, Internet Engineering
   Task Force, Nov. 2001.  Work in progress.

   [15] A. B. Roach, J. Rosenberg, and B. Campbell, "A session
   initiation protocol (SIP) event notification extension for
   collections," internet draft, Internet Engineering Task Force, Feb.
   2003.  Work in progress.

15 Authors' and Editor's Addresses

   The addresses of authors and editors are listed below in alphabetical

   Vijay Gurbani
   2000 Naperville Rd., Room 6G-440
   Naperville, IL 60566-7033

   Krisztian Kiss
   Nokia Research Center
   P.O BOX 100
   33721 Tampere

   Paul Kyzivat
   Cisco Systems
   Mail Stop LWL3/12/2
   900 Chelmsford St.
   Lowell, MA 01851

   Mikko Lonnfors
   Nokia Research Center
   P.O. Box 407
   FIN-00045 Nokia Group

   Jonathan Rosenberg
   72 Eagle Rock Avenue
   First Floor
   East Hanover, NJ 07936

   Henning Schulzrinne
   Dept. of Computer Science
   Columbia University
   1214 Amsterdam Avenue
   New York, NY 10027
   Email: Schulzrinne:

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                           Table of Contents

   1          Introduction ........................................    2
   2          RPIDS Features ......................................    3
   3          Scope ...............................................    4
   4          Terminology and Conventions .........................    5
   5          The Meaning of "open" and "closed" ..................    5
   6          RPIDS Elements ......................................    5
   6.1        Introduction ........................................    5
   6.2        Activity Element ....................................    6
   6.3        Card ................................................    7
   6.4        Class ...............................................    7
   6.5        From Element ........................................    8
   6.6        Icon ................................................    8
   6.7        Idle Element ........................................    8
   6.8        Info ................................................    8
   6.9        Type of Place Element ...............................    8
   6.10       Privacy Element .....................................    9
   6.11       Relationship Element ................................    9
   6.12       Timed Status Element ................................   10
   6.13       Until Element .......................................   10
   7          Examples ............................................   11
   7.1        Presentity with Capabilities ........................   11
   8          XML Schema Definitions ..............................   12
   9          Security Considerations .............................   13
   10         IANA Considerations .................................   14
   10.1       URN Sub-Namespace Registration for ..................   14
   10.2       URN Sub-Namespace Registration for ..................   15
   10.3       Place Type, Device Type, Categories, Relationships
   ................................................................   16
   11         Acknowledgements ....................................   16
   12         References ..........................................   16
   13         Normative References ................................   16
   14         Informative References ..............................   17
   15         Authors' and Editor's Addresses .....................   17