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
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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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found in BCP 78 and BCP 79.
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attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
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