draft-ietf-sipping-conference-package-12.txt   rfc4575.txt 
SIPPING J. Rosenberg Network Working Group J. Rosenberg
Internet-Draft Cisco Systems Request for Comments: 4575 Cisco Systems
Expires: January 2, 2006 H. Schulzrinne Category: Standards Track H. Schulzrinne
Columbia University Columbia University
O. Levin, Ed. O. Levin, Ed.
Microsoft Corporation Microsoft Corporation
July 1, 2005 August 2006
A Session Initiation Protocol (SIP) Event Package for Conference State
draft-ietf-sipping-conference-package-12
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The list of current Internet-Drafts can be accessed at A Session Initiation Protocol (SIP)
http://www.ietf.org/ietf/1id-abstracts.txt. Event Package for Conference State
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Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2005). Copyright (C) The Internet Society (2006).
Abstract Abstract
This document defines a conference event package for tightly coupled This document defines a conference event package for tightly coupled
conferences using the Session Initiation Protocol (SIP) Events conferences using the Session Initiation Protocol (SIP) events
framework, along with a data format used in notifications for this framework, along with a data format used in notifications for this
package. The conference package allows users to subscribe to a package. The conference package allows users to subscribe to a
conference URI. Notifications are sent about changes in the conference Uniform Resource Identifier (URI). Notifications are sent
membership of this conference and optionally about changes in the about changes in the membership of this conference and optionally
state of additional conference components. about changes in the state of additional conference components.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction ....................................................4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Terminology .....................................................4
3. Conference Event Package . . . . . . . . . . . . . . . . . . . 4 3. Conference Event Package ........................................4
3.1 Event Package Name . . . . . . . . . . . . . . . . . . . . 5 3.1. Event Package Name .........................................5
3.2 Filtering . . . . . . . . . . . . . . . . . . . . . . . . 5 3.2. Filtering ..................................................5
3.3 Subscription Duration . . . . . . . . . . . . . . . . . . 5 3.3. Subscription Duration ......................................5
3.4 NOTIFY Bodies . . . . . . . . . . . . . . . . . . . . . . 5 3.4. NOTIFY Bodies ..............................................5
3.5 Notifier Processing of SUBSCRIBE Requests . . . . . . . . 6 3.5. Notifier Processing of SUBSCRIBE Requests ..................6
3.6 Notifier Generation of NOTIFY Requests . . . . . . . . . . 6 3.6. Notifier Generation of NOTIFY Requests .....................6
3.7 Subscriber Processing of NOTIFY Requests . . . . . . . . . 6 3.7. Subscriber Processing of NOTIFY Requests ...................6
3.8 Handling of Forked Requests . . . . . . . . . . . . . . . 7 3.8. Handling of Forked Requests ................................7
3.9 Rate of Notifications . . . . . . . . . . . . . . . . . . 7 3.9. Rate of Notifications ......................................7
3.10 State Agents . . . . . . . . . . . . . . . . . . . . . . . 7 3.10. State Agents ..............................................7
4. Conference Document . . . . . . . . . . . . . . . . . . . . . 7 4. Conference Document .............................................7
4.1 Format . . . . . . . . . . . . . . . . . . . . . . . . . . 7 4.1. Format .....................................................7
4.2 Namespace . . . . . . . . . . . . . . . . . . . . . . . . 7 4.2. Namespace ..................................................7
4.3 Versioning . . . . . . . . . . . . . . . . . . . . . . . . 8 4.3. Versioning .................................................8
4.4 Partial Notifications Mechanism . . . . . . . . . . . . . 8 4.4. Partial Notifications Mechanism ............................8
4.5 Element Keys . . . . . . . . . . . . . . . . . . . . . . . 9 4.5. Element Keys ...............................................9
4.6 Constructing Coherent State Procedure . . . . . . . . . . 9 4.6. Constructing Coherent State Procedure ......................9
5. Conference Data . . . . . . . . . . . . . . . . . . . . . . . 11 5. Conference Data ................................................11
5.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.1. Overview ..................................................11
5.2 <conference-info> . . . . . . . . . . . . . . . . . . . . 13 5.2. <conference-info> .........................................13
5.3 <conference-description> . . . . . . . . . . . . . . . . . 14 5.3. <conference-description> ..................................14
5.3.1 <conf-uris> . . . . . . . . . . . . . . . . . . . . . 14 5.3.1. <conf-uris> ........................................14
5.3.2 <service-uris> . . . . . . . . . . . . . . . . . . . . 15 5.3.2. <service-uris> .....................................15
5.3.3 <maximum-user-count> . . . . . . . . . . . . . . . . . 16 5.3.3. <maximum-user-count> ...............................16
5.3.4 <available-media> . . . . . . . . . . . . . . . . . . 16 5.3.4. <available-media> ..................................16
5.4 <host-info> . . . . . . . . . . . . . . . . . . . . . . . 17 5.4. <host-info> ...............................................17
5.4.1 <display-text> . . . . . . . . . . . . . . . . . . . . 17 5.4.1. <display-text> .....................................17
5.4.2 <web-page> . . . . . . . . . . . . . . . . . . . . . . 17 5.4.2. <web-page> .........................................17
5.4.3 <uris> . . . . . . . . . . . . . . . . . . . . . . . . 17 5.4.3. <uris> .............................................17
5.5 <conference-state> . . . . . . . . . . . . . . . . . . . . 17 5.5. <conference-state> ........................................17
5.5.1 <user-count> . . . . . . . . . . . . . . . . . . . . . 17 5.5.1. <user-count> .......................................17
5.5.2 <active> . . . . . . . . . . . . . . . . . . . . . . . 17 5.5.2. <active> ...........................................18
5.5.3 <locked> . . . . . . . . . . . . . . . . . . . . . . . 18 5.5.3. <locked> ...........................................18
5.6 <users> and its <user> sub-elements . . . . . . . . . . . 18 5.6. <users> and Its <user> Sub-elements .......................18
5.6.1 <display-text> . . . . . . . . . . . . . . . . . . . . 19 5.6.1. <display-text> .....................................19
5.6.2 <associated-aors> . . . . . . . . . . . . . . . . . . 19 5.6.2. <associated-aors> ..................................19
5.6.3 <roles> . . . . . . . . . . . . . . . . . . . . . . . 19 5.6.3. <roles> ............................................19
5.6.4 <languages> . . . . . . . . . . . . . . . . . . . . . 19 5.6.4. <languages> ........................................19
5.6.5 <cascaded-focus> . . . . . . . . . . . . . . . . . . . 19 5.6.5. <cascaded-focus> ...................................19
5.6.6 <endpoint> . . . . . . . . . . . . . . . . . . . . . . 19 5.6.6. <endpoint> .........................................20
5.7 <endpoint> . . . . . . . . . . . . . . . . . . . . . . . . 20 5.7. <endpoint> ................................................20
5.7.1 <display-text> . . . . . . . . . . . . . . . . . . . . 20 5.7.1. <display-text> .....................................20
5.7.2 <referred> . . . . . . . . . . . . . . . . . . . . . . 20 5.7.2. <referred> .........................................21
5.7.3 <status> . . . . . . . . . . . . . . . . . . . . . . . 21 5.7.3. <status> ...........................................21
5.7.4 <joining-method> . . . . . . . . . . . . . . . . . . . 22 5.7.4. <joining-method> ...................................22
5.7.5 <joining-info> . . . . . . . . . . . . . . . . . . . . 22 5.7.5. <joining-info> .....................................23
5.7.6 <disconnection-method> . . . . . . . . . . . . . . . . 23 5.7.6. <disconnection-method> .............................23
5.7.7 <disconnection-info> . . . . . . . . . . . . . . . . . 23 5.7.7. <disconnection-info> ...............................23
5.7.8 <media> . . . . . . . . . . . . . . . . . . . . . . . 24 5.7.8. <media> ............................................24
5.7.9 <call-info> . . . . . . . . . . . . . . . . . . . . . 24 5.7.9. <call-info> ........................................24
5.8 <media> . . . . . . . . . . . . . . . . . . . . . . . . . 24 5.8. <media> ...................................................24
5.8.1 <display-text> . . . . . . . . . . . . . . . . . . . . 25 5.8.1. <display-text> .....................................25
5.8.2 <type> . . . . . . . . . . . . . . . . . . . . . . . . 25 5.8.2. <type> .............................................25
5.8.3 <label> . . . . . . . . . . . . . . . . . . . . . . . 25 5.8.3. <label> ............................................25
5.8.4 <src-id> . . . . . . . . . . . . . . . . . . . . . . . 25 5.8.4. <src-id> ...........................................25
5.8.5 <status> . . . . . . . . . . . . . . . . . . . . . . . 26 5.8.5. <status> ...........................................26
5.9 Sidebars . . . . . . . . . . . . . . . . . . . . . . . . . 26 5.9. Sidebars ..................................................26
5.9.1 <sidebars-by-ref> . . . . . . . . . . . . . . . . . . 26 5.9.1. <sidebars-by-ref> ..................................26
5.9.2 <sidebar-by-val> . . . . . . . . . . . . . . . . . . . 26 5.9.2. <sidebar-by-val> ...................................26
6. XML Schema . . . . . . . . . . . . . . . . . . . . . . . . . . 26 6. XML Schema .....................................................26
7. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 7. Examples .......................................................35
7.1 Basic Example . . . . . . . . . . . . . . . . . . . . . . 35 7.1. Basic Example .............................................35
7.2 Rich Example . . . . . . . . . . . . . . . . . . . . . . . 36 7.2. Rich Example ..............................................36
8. Security Considerations . . . . . . . . . . . . . . . . . . . 40 8. Security Considerations ........................................40
8.1 Connection Security . . . . . . . . . . . . . . . . . . . 40 8.1. Connection Security .......................................40
8.2 Authorization Considerations . . . . . . . . . . . . . . . 41 8.2. Authorization Considerations ..............................41
9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 41 9. IANA Considerations ............................................41
9.1 conference Event Package Registration . . . . . . . . . . 41 9.1. conference Event Package Registration .....................41
9.2 application/conference-info+xml MIME Registration . . . . 42 9.2. application/conference-info+xml MIME Registration .........42
9.3 URN Sub-Namespace Registration for 9.3. URN Sub-Namespace Registration for ........................43
urn:ietf:params:xml:ns:conference-info . . . . . . . . . . 42 9.4. XML Schema Registration ...................................43
9.4 XML Schema Registration . . . . . . . . . . . . . . . . . 43 9.5. URI Purposes Sub-registry Establishment ...................44
9.5 URI Purposes Sub-registry Establishment . . . . . . . . . 43 10. Acknowledgements ..............................................45
10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 44 11. References ....................................................45
11. References . . . . . . . . . . . . . . . . . . . . . . . . . 45 11.1. Normative References .....................................45
11.1 Normative References . . . . . . . . . . . . . . . . . . . 45 11.2. Informative References ...................................46
11.2 Informative References . . . . . . . . . . . . . . . . . . 46
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . 47
Intellectual Property and Copyright Statements . . . . . . . . 48
1. Introduction 1. Introduction
The Session Initiation Protocol (SIP) Events Framework [10] defines The Session Initiation Protocol (SIP) events framework [10] defines
general mechanisms for subscribing to, and receiving notifications general mechanisms for subscribing to, and receiving notifications
of, events within SIP networks. It introduces the notion of a of, events within SIP networks. It introduces the notion of a
package, which is a specific "instantiation" of the events framework package, which is a specific "instantiation" of the events framework
for a well-defined set of events. Here, we define a SIP event for a well-defined set of events. Here, we define a SIP event
package for tightly coupled conferences. This package can be used by package for tightly coupled conferences. This package can be used by
the conference notification service as outlined in the SIP the conference notification service as outlined in the SIP
conferencing framework [16]. As described there, subscriptions to a conferencing framework [16]. As described there, subscriptions to a
conference URI are routed to the focus that is handling the conference URI are routed to the focus that is handling the
conference. It acts as the notifier, and provides clients with conference. It acts as the notifier and provides clients with
updates on conference state. updates on conference state.
The information provided by this package is comprised of conference The information provided by this package is comprised of conference
identifier(s), conference participants (optionally with their identifier(s), conference participants (optionally with their
statuses and media description), conference sidebars, conference statuses and media description), conference sidebars, conference
service URIs, etc. service URIs, etc.
2. Terminology 2. Terminology
In this document, the key words "MUST", "MUST NOT", "REQUIRED", In this document, the key words "MUST", "MUST NOT", "REQUIRED",
skipping to change at page 4, line 40 skipping to change at page 4, line 40
This document uses the conferencing terminology defined in This document uses the conferencing terminology defined in
Conferencing Framework [16]. In addition, the "roster" term is used Conferencing Framework [16]. In addition, the "roster" term is used
to collectively refer to participants in a conference or a sub- to collectively refer to participants in a conference or a sub-
conference. conference.
3. Conference Event Package 3. Conference Event Package
The conference event package allows a user to subscribe to the The conference event package allows a user to subscribe to the
information relating to a conference. In SIP, conferences are information relating to a conference. In SIP, conferences are
represented by URIs. These URIs identify a SIP user agent, called a represented by URIs. These URIs identify a SIP user agent (UA),
focus, that is responsible for ensuring that all users in the called a focus, that is responsible for ensuring that all users in
conference can communicate with each other, as described in the conference can communicate with each other, as described in
Conferencing Framework [16]. The focus has sufficient information Conferencing Framework [16]. The focus has sufficient information
about the state of the conference to inform subscribers about it. about the state of the conference to inform subscribers about it.
It is possible that a participant in the conference may in fact be It is possible that a participant in the conference may in fact be
another focus. In order to provide a more complete participant list, another focus. In order to provide a more complete participant list,
the focus MAY subscribe to the conference package of the other focus the focus MAY subscribe to the conference package of the other focus
to discover the participant list in the cascaded conference. This to discover the participant list in the cascaded conference. This
information can then be included in notifications by use of the information can then be included in notifications by use of the
<cascaded-focus> element as specified by this package. <cascaded-focus> element as specified by this package.
This section provides the details for defining a SIP-specific event This section provides the details for defining a SIP-specific event
notification package, as specified by RFC 3265 [10]. notification package, as specified by RFC 3265 [10].
3.1 Event Package Name 3.1. Event Package Name
The name of this event package is "conference". This package name is The name of this event package is "conference". This package name is
carried in the Event and Allow-Events header, as defined in RFC 3265 carried in the Event and Allow-Events header, as defined in RFC 3265
[10]. [10].
3.2 Filtering 3.2. Filtering
Filters, which can be applied to conference subscriptions, are a Filters, which can be applied to conference subscriptions, are a
desirable feature and can be considered as a subject of future desirable feature and can be considered as a subject of future
standardization activities. This document does not define the standardization activities. This document does not define the
filters for the conference package to be included in the SUBSCRIBE filters for the conference package to be included in the SUBSCRIBE
body. body.
A SUBSCRIBE for a conference package, being sent without a body, A SUBSCRIBE for a conference package, being sent without a body,
implies the default subscription filtering policy. The default implies the default subscription filtering policy. The default
policy is: policy is as follows:
o Notifications are generated every time there is any change in the o Notifications are generated every time there is any change in the
state of the conference. state of the conference.
o Notifications do not normally contain full state; rather, they o Notifications do not normally contain full state; rather, they
only indicate the state that has changed. The exception is a only indicate the state that has changed. The exception is a
NOTIFY sent in response to a SUBSCRIBE. These NOTIFYs contain the NOTIFY sent in response to a SUBSCRIBE. These NOTIFYs contain the
full state of the information requested by the subscriber. full state of the information requested by the subscriber.
3.3 Subscription Duration 3.3. Subscription Duration
The default expiration time for a subscription to a conference is one The default expiration time for a subscription to a conference is one
hour. Once the conference ends, all subscriptions to that particular hour. Once the conference ends, all subscriptions to that particular
conference are terminated, with a reason of "noresource" as defined conference are terminated, with a reason of "noresource" as defined
in RFC 3265 [10]. in RFC 3265 [10].
3.4 NOTIFY Bodies 3.4. NOTIFY Bodies
According to RFC 3265 [10], the NOTIFY message will contain bodies According to RFC 3265 [10], the NOTIFY message will contain bodies
that describe the state of the subscribed resource. This body is in that describe the state of the subscribed resource. This body is in
a format listed in the Accept header field of the SUBSCRIBE, or a a format listed in the Accept header field of the SUBSCRIBE, or a
package-specific default if the Accept header field was omitted from package-specific default if the Accept header field was omitted from
the SUBSCRIBE. the SUBSCRIBE.
In this event package, the body of the notification contains a In this event package, the body of the notification contains a
conference information document that describes the state of a conference information document that describes the state of a
conference. All subscribers and notifiers MUST support the conference. All subscribers and notifiers MUST support the
"application/conference-info+xml" data format described in Section 5. "application/conference-info+xml" data format described in Sections 9
By default, i.e. if no Accept header is specified to a SUBSCRIBE and 5. By default, i.e., if no Accept header is specified to a
request, the NOTIFY will contain a body in the "application/ SUBSCRIBE request, the NOTIFY will contain a body in the
conference-info+xml" data format. If the Accept header field is "application/conference-info+xml" data format. If the Accept header
present, it MUST include "application/conference-info+xml" and MAY field is present, it MUST include "application/conference-info+xml"
include any other types. and MAY include any other types.
3.5 Notifier Processing of SUBSCRIBE Requests 3.5. Notifier Processing of SUBSCRIBE Requests
The conference information contains very sensitive information. The conference information contains very sensitive information.
Therefore, all subscriptions SHOULD be authenticated and then Therefore, all subscriptions SHOULD be authenticated and then
authorized before approval. Authorization policy is at the authorized before approval. Authorization policy is at the
discretion of the administrator, as always. discretion of the administrator, as always.
However, it is RECOMMENDED that all users in the conference be However, it is RECOMMENDED that all users in the conference be
allowed to subscribe to the conference event package. allowed to subscribe to the conference event package.
3.6 Notifier Generation of NOTIFY Requests 3.6. Notifier Generation of NOTIFY Requests
Notifications SHOULD be generated for the conference state when a new Notifications SHOULD be generated for the conference state when a new
participant joins (i.e. gets "connected" to) or a participant leaves participant joins (i.e., gets "connected" to) or a participant leaves
(i.e. gets "disconnected" from) the conference. (i.e., gets "disconnected" from) the conference.
Subject to a local focus policy, additional changes in participants' Subject to a local focus policy, additional changes in participants'
status, changes in their media types, and other optional information status, changes in their media types, and other optional information
MAY be reported by the focus. MAY be reported by the focus.
Changes in sidebar rosters SHOULD be reported by the focus to their Changes in sidebar rosters SHOULD be reported by the focus to their
participants and MAY be reported to others, subject to local policy. participants and MAY be reported to others, subject to local policy.
Changes in conference identifiers and service URIs SHOULD be reported Changes in conference identifiers and service URIs SHOULD be reported
by the focus to the Conference package subscribers. by the focus to the conference package subscribers.
Changes in other conference state information MAY be reported by the Changes in other conference state information MAY be reported by the
focus to the Conference package subscribers. focus to the conference package subscribers.
3.7 Subscriber Processing of NOTIFY Requests 3.7. Subscriber Processing of NOTIFY Requests
The SIP Events framework expects packages to specify how a subscriber The SIP events framework expects packages to specify how a subscriber
processes NOTIFY requests in any package specific ways, and in processes NOTIFY requests in any package-specific ways, and in
particular, how it uses the NOTIFY requests to construct a coherent particular, how it uses the NOTIFY requests to construct a coherent
view of the state of the subscribed resource. view of the state of the subscribed resource.
Typically, the NOTIFY for the conference package will only contain Typically, the NOTIFY for the conference package will only contain
information about those users whose state in the conference has information about those users whose state in the conference has
changed. To construct a coherent view of the total state of all changed. To construct a coherent view of the total state of all
users, a subscriber to the conference package will need to combine users, a subscriber to the conference package will need to combine
NOTIFYs received over time. NOTIFYs received over time.
Notifications within this package can convey partial information; Notifications within this package can convey partial information;
that is, they can indicate information about a subset of the state that is, they can indicate information about a subset of the state
associated with the subscription. This means that an explicit associated with the subscription. This means that an explicit
algorithm needs to be defined in order to construct coherent and algorithm needs to be defined in order to construct coherent and
consistent state. The details of this mechanism are specific to the consistent state. The details of this mechanism are specific to the
particular document type. See Section 4.6 for information on particular document type. See Section 4.6 for information on
constructing coherent information from an application/ constructing coherent information from an application/
conference-info+xml document. conference-info+xml document.
3.8 Handling of Forked Requests 3.8. Handling of Forked Requests
By their nature, the conferences supported by this package are By their nature, the conferences supported by this package are
centralized. Therefore, SUBSCRIBE requests for a conference should centralized. Therefore, SUBSCRIBE requests for a conference should
not generally fork. If forking happens in the network, subscribers not generally fork. If forking happens in the network, subscribers
to this package MUST NOT establish more than a single SIP dialog as a to this package MUST NOT establish more than a single SIP dialog as a
result of a single SUBSCRIBE request. In the foci cascading case, result of a single SUBSCRIBE request. In the foci cascading case,
detailed conference information can be retrieved by establishing an detailed conference information can be retrieved by establishing an
individual SUBSCRIBE dialog with each participating focus. individual SUBSCRIBE dialog with each participating focus.
3.9 Rate of Notifications 3.9. Rate of Notifications
For reasons of congestion control, it is important that the rate of For reasons of congestion control, it is important that the rate of
notifications not become excessive. As a result, it is RECOMMENDED notifications not become excessive. As a result, it is RECOMMENDED
that the server doesn't generate notifications for a single that the server does not generate notifications for a single
subscriber at a rate faster than once every 5 seconds. subscriber at a rate faster than once every 5 seconds.
3.10 State Agents 3.10. State Agents
Conference state is ideally maintained in the element in which the Conference state is ideally maintained in the element in which the
conference resides. Therefore, a conference focus is the best suited conference resides. Therefore, a conference focus is the best-suited
element to handle subscriptions to it. Cascaded foci MAY implement element to handle subscriptions to it. Cascaded foci MAY implement
state agents (as defined in RFC 3265 [10]) for this package. state agents (as defined in RFC 3265 [10]) for this package.
4. Conference Document 4. Conference Document
4.1 Format 4.1. Format
Conference information is an XML document that MUST be well-formed Conference information is an XML document that MUST be well-formed
and valid. It MUST be based on Extensible Markup Language (XML) 1.0 and valid. It MUST be based on Extensible Markup Language (XML) 1.0
and MUST be encoded using UTF-8 [14]. and MUST be encoded using UTF-8 [14].
4.2 Namespace 4.2. Namespace
This specification makes use of XML namespaces for identifying This specification makes use of XML namespaces for identifying
conference information documents and document fragments. The conference information documents and document fragments. The
namespace URI for elements defined by this specification is a URN namespace URI for elements defined by this specification is a Uniform
[2], using the namespace identifier 'ietf' defined by [6] and Resource Namespace (URN) [2], using the namespace identifier 'ietf'
extended by RFC 3688 [21]. This URN is: defined by [6] and extended by RFC 3688 [21]. This URN is as
follows:
urn:ietf:params:xml:ns:conference-info urn:ietf:params:xml:ns:conference-info
4.3 Versioning 4.3. Versioning
The conference information is described by a hierarchal XML structure The conference information is described by a hierarchical XML
with the root element <conference-info>. The root element is the structure with the root element <conference-info>. The root element
only element in the schema that carries meaningful version number for is the only element in the schema that carries a meaningful version
all the elements in the document. The whole conference information number for all the elements in the document. The whole conference
is associated with this version number. information is associated with this version number.
The 'version' attribute MUST be included in the root <conference- The 'version' attribute MUST be included in the root
info> element. <conference-info> element.
4.4 Partial Notifications Mechanism 4.4. Partial Notifications Mechanism
This specification defines a basic partial notifications mechanism by This specification defines a basic partial notifications mechanism by
using a 'state' attribute as described below. This mechanism MUST be using a 'state' attribute as described below. This mechanism MUST be
supported by all subscribing clients. Additional general partial supported by all subscribing clients. Additional general partial
notifications mechanisms can be defined and applied to this package notifications mechanisms can be defined and applied to this package
in the future. in the future.
All sub-elements in the <conference-info> hierarchal XML structure All sub-elements in the <conference-info> hierarchical XML structure
can be classified in two groups: permissible for partial can be classified in two groups: permissible for partial
notifications or not. Elements that carry a substantial amount of notifications or not. Elements that carry a substantial amount of
data that is subject to frequent changes are permissible for partial data that is subject to frequent changes are permissible for partial
notifications and have a 'state' attribute attached to them. All notifications and have a 'state' attribute attached to them. All
future extensions to this schema MUST define which extension elements future extensions to this schema MUST define which extension elements
can also use this mechanism. All other elements can be updated as can also use this mechanism. All other elements can be updated as
atomic pieces of data only. atomic pieces of data only.
Below is the complete list of elements permissible to use the partial Below is the complete list of elements permissible to use the partial
notifications mechanism defined in this specification. (Note that notifications mechanism defined in this specification. (Note that
skipping to change at page 8, line 44 skipping to change at page 9, line 4
notifications mechanism defined in this specification. (Note that notifications mechanism defined in this specification. (Note that
future partial notifications mechanisms can potentially be applicable future partial notifications mechanisms can potentially be applicable
to additional elements.) to additional elements.)
o Element <conference-info> o Element <conference-info>
o Element <users> o Element <users>
o Element <user> o Element <user>
o Element <endpoint> o Element <endpoint>
o Element <sidebars-by-val> o Element <sidebars-by-val>
o Element <sidebars-by-ref> o Element <sidebars-by-ref>
The 'state' attribute value indicates whether the reported The 'state' attribute value indicates whether the reported
information about the element is "full", "partial" or the element is information about the element is "full" or "partial", or whether the
"deleted" from the conference state document. The default value of element has been "deleted" from the conference state document. The
any 'state' attribute is "full". default value of any 'state' attribute is "full".
A 'state' attribute of a child element in the document MUST be A 'state' attribute of a child element in the document MUST be
consistent with its parent 'state'. This means that if the parent's consistent with its parent 'state'. This means that if the parent's
'state' is "full", the state of its children MUST be "full". If the 'state' is "full", the state of its children MUST be "full". If the
parent's 'state' is "partial", the state of its children MAY be parent's 'state' is "partial", the state of its children MAY be
either "partial", "full", or "deleted". A parent element with either "partial", "full", or "deleted". A parent element with
"deleted" 'state' SHOULD NOT contain child elements. Any information "deleted" 'state' SHOULD NOT contain child elements. Any information
provided for child elements of a "deleted" parent MUST be ignored by provided for child elements of a "deleted" parent MUST be ignored by
the package subscriber. the package subscriber.
4.5 Element Keys 4.5. Element Keys
The defined XML schema has a property of unique identification among The defined XML schema has a property of unique identification among
sub-elements of a common parent, which makes it possible to use the sub-elements of a common parent, which makes it possible to use the
partial notifications mechanism defined in this document. This partial notifications mechanism defined in this document. This
property is achieved by defining a key to each sub-element that can property is achieved by defining a key to each sub-element that can
appear multiple times under the common parent. appear multiple times under the common parent.
In the context of this specification, the element key is the set of In the context of this specification, the element key is the set of
mandatory attributes or sub-elements of an element. The key value mandatory attributes or sub-elements of an element. The key value
MUST be unique for the element among its siblings of the same type. MUST be unique for the element among its siblings of the same type.
In the context of this specification, two keys of type xs:anyURI are In the context of this specification, two keys of type xs:anyURI are
considered to be equal if the UTF-8 representations of the keys considered to be equal if the UTF-8 representations of the keys
(including all URI parameters that can be included with the URI) are (including all URI parameters that can be included with the URI) are
identical. Consequently, it is NOT RECOMMENDED using relative URIs identical. Consequently, using relative URIs and lexical white space
and lexical white space in these keys. in these keys is NOT RECOMMENDED.
Below is the list of elements (subject to partial notifications of Below is the list of elements (subject to partial notifications of
their parent elements) with their keys as defined by this their parent elements) with their keys as defined by this
specification: specification:
o Element <user> uses as the key 'entity' o Element <user> uses as the key 'entity'
o Element <endpoint> uses as the key 'entity' o Element <endpoint> uses as the key 'entity'
o Element <media> uses as the key 'id' o Element <media> uses as the key 'id'
o Element <entry> (child to <sidebars-by-val>) uses as the key o Element <entry> (child to <sidebars-by-val>) uses as the key
'entity' 'entity'
o Element <sidebars-by-ref> uses as the key <uri> o Element <sidebars-by-ref> uses as the key <uri>
4.6 Constructing Coherent State Procedure 4.6. Constructing Coherent State Procedure
This section describes the algorithm for constructing a coherent This section describes the algorithm for constructing a coherent
conference state by a subscriber to the conference package. Using conference state by a subscriber to the conference package. Using
software programming abstraction, the subscriber maintains a single software programming abstraction, the subscriber maintains a single
local version number for the whole conference document and a local local version number for the whole conference document and a local
element instance for each element in the schema. Also, for each element instance for each element in the schema. Also, for each
element with keys (as defined above), the subscriber maintains a element with keys (as defined above), the subscriber maintains a
virtual table with a row for each existing key value. virtual table with a row for each existing key value.
The first time a NOTIFY with a "full" document is received (as The first time a NOTIFY with a "full" document is received (as
indicated by the value of the 'state' attribute in the <conference- indicated by the value of the 'state' attribute in the
info> element), the conference package subscriber MUST set the local <conference-info> element), the conference package subscriber MUST
'version' number to the value of the 'version' attribute from the set the local 'version' number to the value of the 'version'
received <conference-info> and populate local data with the received attribute from the received <conference-info> and populate local data
information. with the received information.
Each time a new NOTIFY is received, the value of the local version Each time a new NOTIFY is received, the value of the local version
number and the value of the 'version' attribute in the new received number and the value of the 'version' attribute in the new received
document are compared. If the value in the document is equal or less document are compared. If the value in the document is equal to or
than the local version, the document is discarded without processing. less than the local version, the document is discarded without
processing.
Otherwise, if the received NOTIFY contains a "full" or "deleted" Otherwise, if the received NOTIFY contains a "full" or "deleted"
state, the conference package subscriber MUST set the local 'version' state, the conference package subscriber MUST set the local 'version'
number to the value of the 'version' attribute from the received number to the value of the 'version' attribute from the received
<conference-info> and replace the local information with the received <conference-info> and replace the local information with the received
document. Receiving "deleted" state for the <conference-info> document. Receiving "deleted" state for the <conference-info>
element means that the conference has ceased to exist and the element means that the conference has ceased to exist and the
subscriber SHOULD terminate the subscription by sending the SUBSCRIBE subscriber SHOULD terminate the subscription by sending the SUBSCRIBE
with Expires = 0. with Expires = 0.
Otherwise (i.e. if the received NOTIFY contains "partial" state), if Otherwise (i.e., if the received NOTIFY contains "partial" state), if
the 'version' number in the received document is more than one number the 'version' number in the received document is more than one number
higher than the previous local version number, the subscriber MUST higher than the previous local version number, the subscriber MUST
generate a subscription refresh request to trigger a full state generate a subscription refresh request to trigger a full state
notification. If the 'version' number in the document is one higher notification. If the 'version' number in the document is one higher
than the local version number, the local version number is updated than the local version number, the local version number is updated
accordingly and the document is used to update the local content as accordingly and the document is used to update the local content as
described below. described below.
For each sub-element of the <conference-info> element in the received For each sub-element of the <conference-info> element in the received
document, document,
1. If the element contains "full" state, the whole local element 1. If the element contains "full" state, the whole local element
content is flushed and repopulated from the document. content is flushed and repopulated from the document.
2. Otherwise, if the element contains "deleted" state, the whole 2. Otherwise, if the element contains "deleted" state, the whole
element MUST be removed from the local content. element MUST be removed from the local content.
3. Otherwise, if the element contains "partial" state: 3. Otherwise, if the element contains "partial" state:
3.1 For elements with keys, the subscriber compares the keys received 3.1. For elements with keys, the subscriber compares the keys
in the update with the keys in the local tables. received in the update with the keys in the local tables.
3.1.1 If a key does not exist in the local table, a row is added, and 3.1.1. If a key does not exist in the local table, a row is
its content is set to the element information from the update. added, and its content is set to the element
information from the update.
3.1.2 Otherwise, if a key of the same value does exist, for each sub- 3.1.2. Otherwise, if a key of the same value does exist, for
element in the row the algorithm is applied from step 3.2. each sub-element in the row, the algorithm is applied
from step 3.2.
3.2 For each atomic element received in the schema, the element is 3.2. For each atomic element received in the schema, the element
replaced with the new information as a whole. For each non-atomic is replaced with the new information as a whole. For each
element received in the schema with either no 'state' attribute non-atomic element received in the schema with either no
included or the state attribute is set to "full", the element is 'state' attribute included or the state attribute is set to
replaced with the new information as a whole. Also, for each element "full", the element is replaced with the new information as a
with the state attribute set to "deleted", the whole element is whole. Also, for each element with the state attribute set
removed from the local content. to "deleted", the whole element is removed from the local
content.
3.3 For each non-atomic element with the state attribute set to 3.3. For each non-atomic element with the state attribute set to
"partial", the algorithm is applied recursively starting from step "partial", the algorithm is applied recursively starting from
3.1. step 3.1.
5. Conference Data 5. Conference Data
5.1 Overview 5.1. Overview
The <conference-info> document format is designed to convey The <conference-info> document format is designed to convey
information about the conference and about participation in the information about the conference and about participation in the
conference. The following non-normative diagram gives an example of conference. The following non-normative diagram gives an example of
the overall hierarchy used in this format. Conferences contain users the overall hierarchy used in this format. Conferences contain users
who can be represented by multiple endpoints, each of which can have who can be represented by multiple endpoints, each of which can have
multiple media streams. Conferences can also include or reference multiple media streams. Conferences can also include or reference
"sidebar conferences". When sidebar information is incorporated into "sidebar conferences". When sidebar information is incorporated into
a conference information document in a <sidebar-by-value> element, a conference information document in a <sidebars-by-val> element,
each <entry> element represents a sidebar and can include any sub- each <entry> element represents a sidebar and can include any
elements permitted in the <conference-info> top-level element. sub-elements permitted in the <conference-info> top-level element.
conference-info conference-info
| |
|-- conference-description |-- conference-description
| |
|-- host-info |-- host-info
| |
|-- conference-state |-- conference-state
| |
|-- users |-- users
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|-- entry |-- entry
| |-- users | |-- users
| |-- user | |-- user
| |-- user | |-- user
|-- entry |-- entry
|-- users |-- users
|-- user |-- user
|-- user |-- user
|-- user |-- user
In most cases, this document doesn't mandate how the information, In most cases, this document does not mandate how the information,
presented through the conference document to the subscribers, is presented through the conference document to the subscribers, is
obtained by the focus. In many cases, the information can be obtained by the focus. In many cases, the information can be
dynamically learned from the call signaling and also be manually dynamically learned from the call signaling and can also be manually
populated by an administrator - all subject to local policies. This populated by an administrator - all subject to local policies. This
document specifies what the XML elements mean in order to allow the document specifies what the XML elements mean in order to allow the
subscribers to appropriately interpret it. Some portions of the subscribers to appropriately interpret it. Some portions of the
information are intended for processing by automata, others are for information are intended for processing by automata; others are for
human consumption only. For example, the <display-text> sub-elements human consumption only. For example, the <display-text> sub-elements
of elements <conf-uris>, <service-uris>, <available-media>, <host- of elements <conf-uris>, <service-uris>, <available-media>,
info>, <endpoint>, and <media> are intended for display to human <host-info>, <endpoint>, and <media> are intended for display to
subscribers only. human subscribers only.
Although in multiple places this document states that specific Although in multiple places this document states that specific
information "SHOULD" be communicated to the subscribers, note that information "SHOULD" be communicated to the subscribers, note that
particular conference package subscribers (e.g. representing a particular conference package subscribers (e.g., representing a
moderator, an administrator, or a cascaded focus) rely on accuracy of moderator, an administrator, or a cascaded focus) rely on accuracy of
this information for their proper operation. Therefore, a this information for their proper operation. Therefore, a
conferencing server MUST ensure that all critical changes (stated conferencing server MUST ensure that all critical changes (stated
as "SHOULD") are communicated to these specific subscribers, as "SHOULD") are communicated to these specific subscribers;
otherwise these changes MUST be communicated to all subscribers to otherwise, these changes MUST be communicated to all subscribers to
the conference information. the conference information.
Following sections describe the XML schema in more details. Following sections describe the XML schema in more detail.
5.2 <conference-info> 5.2. <conference-info>
A conference information document begins with the root element tag A conference information document begins with the root element tag
<conference-info> of conference-type. <conference-info> of conference-type.
The following attributes are defined for <conference-info>: The following attributes are defined for <conference-info>:
entity: This attribute contains the conference URI that identifies entity: This attribute contains the conference URI that identifies
the conference being described in the document. This is the SIP the conference being described in the document. This is the SIP
URI that an interested entity needs to SUBSCRIBE to in order to URI that an interested entity needs to SUBSCRIBE to in order to
get the conference package information. Note that this URI can be get the conference package information. Note that this URI can be
listed as one of the URIs to be used in order to access the listed as one of the URIs to be used in order to access the
conference by SIP means and in accordance with Section 5.3.1 conference by SIP means and in accordance with Section 5.3.1
below. below.
state: This attribute indicates whether the document contains the state: This attribute indicates whether the document contains the
whole conference information ("full"), only the information that whole conference information ("full") or only the information that
has changed since the previous document ("partial"), or the has changed since the previous document ("partial"), or whether
conference ceased to exist ("deleted"). For more detail see the conference ceased to exist ("deleted"). For more detail, see
Section 4. Section 4.
version: This attribute allows the recipient of conference version: This attribute allows the recipient of conference
information documents to properly order the received notifications information documents to properly order the received
and it MUST be used with the root <conference-info> element. notifications, and it MUST be used with the root <conference-info>
Version number is a 32 bit monotonically increasing integer scoped element. Version number is a 32-bit monotonically increasing
within a subscription. A server MUST increment the version number integer scoped within a subscription. A server MUST increment the
for each notification (full, partial, and deleted) being sent to a version number for each notification (full, partial, and deleted)
subscriber and reporting a change in the conference document being sent to a subscriber and reporting a change in the
state. For each partial notification, the version number MUST be conference document state. For each partial notification, the
increased by one. Note that a partial notification and a version number MUST be increased by one. Note that a partial
subsequent full notification over the same dialog MAY contain the notification and a subsequent full notification over the same
same version number if no change in the conference state occurred dialog MAY contain the same version number if no change in the
in between. conference state occurred in between.
The <conference-info> element is comprised of <conference- The <conference-info> element is comprised of <conference-
description>, <host-info>, <conference-state>, <users>, <sidebar-by- description>, <host-info>, <conference-state>, <users>,
ref> and <sidebars-by-val> child elements. A "full" conference <sidebars-by-ref> and <sidebars-by-val> child elements. A "full"
document MUST at least include the <conference-description> and conference document MUST at least include the
<users> child elements. <conference-description> and <users> child elements.
Following sections describe these elements in detail. The full XML Following sections describe these elements in detail. The full XML
schema is provided in Section 6. schema is provided in Section 6.
5.3 <conference-description> 5.3. <conference-description>
The <conference-description> element describes the conference as a The <conference-description> element describes the conference as a
whole. whole.
The child elements <display-text>, <subject>, <free-text>, and The child elements <display-text>, <subject>, <free-text>, and
<keywords> are used to describe the conference content: <keywords> are used to describe the conference content:
<display-text>: Contains descriptive text suitable for human <display-text>: Contains descriptive text suitable for human
consumption, for example, listing in a directory consumption, for example, listing in a directory
<subject>: Contains the subject of the conference <subject>: Contains the subject of the conference
<free-text>: Contains an additional longer description of the <free-text>: Contains an additional longer description of the
conference conference
<keywords>: Contains a list of space-separated string tokens that can <keywords>: Contains a list of space-separated string tokens that
be used by search engines to better classify the conference can be used by search engines to better classify the conference
Additional child elements <conf-uris> and <service-uris> are used to Additional child elements <conf-uris> and <service-uris> are used to
describe the conference-related URIs; <maximum-user-count> and describe the conference-related URIs; <maximum-user-count> and
<available-media> are used to describe the overall characteristics. <available-media> are used to describe the overall characteristics.
This information is typically derived from the system conference This information is typically derived from the system conference
policies, is set before the conference activation, and is rarely policies, is set before the conference activation, and is rarely
changed during the conference lifetime. changed during the conference lifetime.
The following sections describe the remaining elements in more The following sections describe the remaining elements in more
detail. Other sub-elements can extend <conference-description> in detail. Other sub-elements can extend <conference-description> in
the future. the future.
5.3.1 <conf-uris> 5.3.1. <conf-uris>
This element contains a sequence of <entry> child elements - each This element contains a sequence of <entry> child elements - each
containing the URI to be used in order to access the conference by containing the URI to be used in order to access the conference by
different signaling means. The value of the URI MUST be unique in different signaling means. The value of the URI MUST be unique in
the conference context and is included in the <uri> sub-element. the conference context and is included in the <uri> sub-element.
Each <entry> MAY contain additional information useful to the Each <entry> MAY contain additional information useful to the
participant when accessing the conference. participant when accessing the conference.
An <entry> element MAY contain the <display-text> sub-element that An <entry> element MAY contain the <display-text> sub-element that
provides a textual description meant for human consumption. provides a textual description meant for human consumption.
Each <entry> element SHOULD contain a <purpose> sub-element that Each <entry> element SHOULD contain a <purpose> sub-element that
describes what happens when accessing the URI. The currently defined describes what happens when accessing the URI. The currently defined
<purpose> values to be used with the <conf-uris> are: <purpose> values to be used with the <conf-uris> are the following:
participation: Accessing a URI with this <purpose> will bring the participation: Accessing a URI with this <purpose> will bring the
party into the conference party into the conference.
streaming: Accessing a URI with this <purpose> will commence streaming: Accessing a URI with this <purpose> will commence
streaming the conference, but not allow active participation streaming the conference, but not allow active participation.
Examples of suitable URI schemes include sip: and sips: [8], xmpp: Examples of suitable URI schemes include sip: and sips: [8], xmpp:
[22], h323: [20], and tel: [19] URIs. The rtsp [18] URI is suitable [22], h323: [20], and tel: [19] URIs. The rtsp [18] URI is suitable
for streaming. for streaming.
Future extensions to this schema may define new values and register Future extensions to this schema may define new values and register
them with IANA under the registry established by this specification. them with IANA under the registry established by this specification.
5.3.2 <service-uris> 5.3.2. <service-uris>
This element describes auxiliary services available for the This element describes auxiliary services available for the
conference. Like <conference-uris>, this element contains a set of conference. Like <conference-uris>, this element contains a set of
<entry> child elements - each containing the URI to be used in order <entry> child elements - each containing the URI to be used in order
to access different services available for the particular conference. to access different services available for the particular conference.
The value of the URI MUST be unique in the conference context and is The value of the URI MUST be unique in the conference context and is
included in the <uri> sub-element. included in the <uri> sub-element.
An <entry> element MAY contain the <display-text> sub-element that An <entry> element MAY contain the <display-text> sub-element that
provides a textual description meant for user consumption. provides a textual description meant for user consumption.
Each <entry> element SHOULD contain a <purpose> sub-element. The Each <entry> element SHOULD contain a <purpose> sub-element. The
currently defined <purpose> values to be used with the <service-uris> currently defined <purpose> values to be used with the <service-uris>
are: are the following:
web-page: Indicates the web page containing the additional web-page: Indicates the web page containing the additional
information about the conference information about the conference.
recording: Indicates the link at which the recorded conference recording: Indicates the link at which the recorded conference
context can be retrieved context can be retrieved.
event: Indicates the URI at which a subscription to the conference event: Indicates the URI at which a subscription to the conference
event package may be requested. This would typically be the event package may be requested. This would typically be the
conference URI of the main conference conference URI of the main conference.
Future extensions to this schema may define new values and register Future extensions to this schema may define new values and register
them with IANA under the registry established by this specification. them with IANA under the registry established by this specification.
5.3.3 <maximum-user-count> 5.3.3. <maximum-user-count>
The value of this element provides a hint to the recipient of the The value of this element provides a hint to the recipient of the
conference document about the number of users that can be invited to conference document about the number of users that can be invited to
the conference. Typically, this value represents the overall number the conference. Typically, this value represents the overall number
of users allowed to join the conference by different means as of users allowed to join the conference by different means as
published through the conference document in <conf-uris>. Note that published through the conference document in <conf-uris>. Note that
this value is set by an administrator and can reflect any local this value is set by an administrator and can reflect any local
policies combination such as network consumption, CPU processing policies combination such as network consumption, CPU processing
power, and licensing rules. power, and licensing rules.
5.3.4 <available-media> 5.3.4. <available-media>
This element contains a sequence of <entry> child elements of This element contains a sequence of <entry> child elements of
conference-medium-type, each being indexed by the attribute 'label'. conference-medium-type, each being indexed by the attribute 'label'.
The 'label' attribute is the media stream identifier assigned by the The 'label' attribute is the media stream identifier assigned by the
conferencing server: its value will be unique in the <conference- conferencing server: its value will be unique in the
info> context. The value of this attribute will typically correspond <conference-info> context. The value of this attribute will
to the Session Description Protocol (SDP) "label" media attribute typically correspond to the Session Description Protocol (SDP)
defined in [17]. "label" media attribute defined in [17].
Each <entry> describes a single media stream available to the Each <entry> describes a single media stream available to the
participants in the conference and contains the following participants in the conference and contains the following
information: information:
<display-text> This element contains the display text for the media <display-text>: This element contains the display text for the media
stream. stream.
<type> This element contains the media type of the media stream. The <type>: This element contains the media type of the media stream.
value of this element MUST be one of the values registered for The value of this element MUST be one of the values registered for
"media" of SDP [3] and its later revision(s). For example: "media" of SDP [3] and its later revision(s), for example,
"audio", "video", "text", and "message". "audio", "video", "text", and "message".
<status> This element indicates the available status of the media <status>: This element indicates the available status of the media
stream available to the conference participants. For example, stream available to the conference participants. For example,
this would be the status of the media stream, which would be this would be the status of the media stream, which would be
offered by the focus, in a 'dial-out' scenario. Using normal SIP offered by the focus, in a 'dial-out' scenario. Using normal SIP
offer answer mechanisms (being defined in RFC 3264 [9])in both offer/answer mechanisms (being defined in RFC 3264 [9]) in both
dial-in and dial-out scenarios, a participant can of course dial-in and dial-out scenarios, a participant can of course
establish only a subset of the available stream (i.e., request or establish only a subset of the available stream (i.e., request or
accept the stream in one direction only, if both directions are accept the stream in one direction only, if both directions are
available). The valid values are "sendrecv", "sendonly", available). The valid values are "sendrecv", "sendonly",
"recvonly", or "inactive" as defined in SDP [3] and its later "recvonly", or "inactive" as defined in SDP [3] and its later
revision(s). (Note that the value specifies the direction from revision(s). (Note that the value specifies the direction from
the participants' point of view.) the participants' point of view.)
5.4 <host-info> 5.4. <host-info>
This element contains information about the entity hosting the This element contains information about the entity hosting the
conference. This information is set before the conference conference. This information is set before the conference
activation, and is rarely changed during the conference lifetime, activation, and it is rarely changed during the conference lifetime,
unless the whole conference is moved to be hosted by another entity. unless the whole conference is moved to be hosted by another entity.
The host information is comprised of the following elements: The host information is comprised of the following elements:
5.4.1 <display-text> 5.4.1. <display-text>
This element contains display text describing the entity hosting the This element contains display text describing the entity hosting the
conference. conference.
5.4.2 <web-page> 5.4.2. <web-page>
This element contains HTTP: or HTTPS: URI of a web page describing This element contains HTTP: or HTTPS: URI of a web page describing
either the conference service or the user hosting the conference. either the conference service or the user hosting the conference.
5.4.3 <uris> 5.4.3. <uris>
This element contains a set of <entry> child elements, each This element contains a set of <entry> child elements, each
containing the URI value and optionally its description. containing the URI value and optionally its description.
5.5 <conference-state> 5.5. <conference-state>
By including this element in the conference document, the server can By including this element in the conference document, the server can
inform the subscribers about the changes in the overall conference inform the subscribers about the changes in the overall conference
information. The <conference-state> child elements are described information. The <conference-state> child elements are described
below. below.
5.5.1 <user-count> 5.5.1. <user-count>
The value of this element tells the recipient of the conference The value of this element tells the recipient of the conference
document the overall number of users participating in the conference document the overall number of users participating in the conference
at a certain moment. Typically this value represents the overall at a certain moment. Typically, this value represents the overall
number of users who joined the conference by different means as number of users who joined the conference by different means as
published through the conference document in <conf-uris>. Note that published through the conference document in <conf-uris>. Note that
this number does not necessarily need to match and MAY exceed the this number does not necessarily need to match and MAY exceed the
number of the entries in the <users> container. For example, in number of the entries in the <users> container. For example, in a
lecturing scenario a large conference notifications may not include lecturing scenario, large conference notifications may not include
every participant in the <users> element, but instead report only the every participant in the <users> element, but instead report only the
panelists or the speakers. panelists or the speakers.
5.5.2 <active> 5.5.2. <active>
This Boolean element indicates whether the conference is currently This Boolean element indicates whether the conference is currently
active or not. A conference is active if calling one of the <conf- active. A conference is active if calling one of the <conf-uris> by
uris> by an authorized client results in successful establishment of an authorized client results in successful establishment of a
a signaling session between the client and the focus and a successful signaling session between the client and the focus and a successful
joining of the conference. joining of the conference.
5.5.3 <locked> 5.5.3. <locked>
This Boolean element says whether the conference is currently locked This Boolean element says whether the conference is currently locked.
or not. In this context, "locked" means that the conference roster In this context, "locked" means that the conference roster cannot be
can not be added to (although participants may leave or be removed added to (although participants may leave or be removed from the
from the conference). conference).
5.6 <users> and its <user> sub-elements 5.6. <users> and Its <user> Sub-elements
The <users> element is a container of <user> child elements, each The <users> element is a container of <user> child elements, each
describing a single participant in the conference. describing a single participant in the conference.
The following attributes are defined for <user> element: The following attributes are defined for <user> element:
entity: This attribute contains the URI for the user in the entity: This attribute contains the URI for the user in the
conference. This is a logical identifier, which corresponds to conference. This is a logical identifier, which corresponds to
the call signaling authenticated identity of the participant. The the call signaling authenticated identity of the participant. The
'entity' value MUST be unique among all participants in the 'entity' value MUST be unique among all participants in the
conference. If for some participants, the focus decides to not conference. If, for some participants, the focus decides not to
reveal this information (due to local policies or security reveal this information (e.g., due to local policies or security
reasons, for example), the host portion of the user URI MUST use reasons), the host portion of the user URI MUST use the .invalid
the .invalid top level domain (TLD) according to definitions of top level domain (TLD) according to definitions of RFC 2606 [5].
RFC 2606 [5]. The focus also MUST construct the user portion of The focus also MUST construct the user portion of the URI so that
the URI so that the URI is unique among all participants of the the URI is unique among all participants of the same domain. For
same domain. For example, the convention example, the convention
"AnonymousX" <sip:anonymousX@anonymous.invalid> "AnonymousX" <sip:anonymousX@anonymous.invalid>
SHOULD be used for a participant requesting privacy in accordance SHOULD be used for a participant requesting privacy in accordance
with the guidelines for generating anonymous URIs of RFC 3323 with the guidelines for generating anonymous URIs of RFC 3323 [11].
[11]. Note that in a different case, such as when used in Note that in a different case, such as when used in conjunction with
conjunction with Enhancements for Authenticated Identity Enhancements for Authenticated Identity Management in SIP [25], the
Management in SIP [25], the following convention can be used: following convention can be used:
"AnonymousX" <sip:anonymousX@example.com> "AnonymousX" <sip:anonymousX@example.com>
state: This attribute indicates whether the document contains the state: This attribute indicates whether the document contains the
whole user information ("full"), only the information that has whole user information ("full") or only the information that has
changed since the previous document ("partial"), or the user was changed since the previous document ("partial"), or whether the
removed from the conference ("deleted"). user was removed from the conference ("deleted").
The following child elements are defined for <user> element: The following child elements are defined for <user> element:
5.6.1 <display-text> 5.6.1. <display-text>
This element is used to display the user friendly name in the This element is used to display the user-friendly name in the
conference. conference.
5.6.2 <associated-aors> 5.6.2. <associated-aors>
This element contains additional (to the 'entity') URIs being This element contains additional (to the 'entity') URIs being
associated with the <user>. Typically, this information will be associated with the <user>. Typically, this information will be
manually provided by an administrator showing the logical association manually provided by an administrator showing the logical association
between signaling entities otherwise independent. For example, if between signaling entities otherwise independent. For example, if
the 'entity' of a <user> contains a GRUU Globally Routable User URI the 'entity' of a <user> contains a Globally Routable User URI (GRUU)
[24] or tel: URI RFC 3966 [19], it would be useful to populate this [24] or tel: URI RFC 3966 [19], it would be useful to populate this
field with the Address of Record (AOR) of the person, who uses these field with the Address of Record (AOR) of the person who uses these
devices, each represented as an independent <user>. devices, each represented as an independent <user>.
5.6.3 <roles> 5.6.3. <roles>
This element MAY contain a set of human readable strings describing This element MAY contain a set of human-readable strings describing
the roles of the user in the conference. Note that this information the roles of the user in the conference. Note that this information
is applicable for human consumption only. This specification doesn't is applicable for human consumption only. This specification does
define the set of possible conferencing roles nor the semantics not define the set of possible conferencing roles or the semantics
associated with each. It is expected that future conferencing associated with each. It is expected that future conferencing
specifications will define these and the corresponding schema specifications will define these and the corresponding schema
extensions, as appropriate. extensions, as appropriate.
5.6.4 <languages> 5.6.4. <languages>
This element contains a list of tokens, separated by spaces, each This element contains a list of tokens, separated by spaces, each
containing a language understood by the user. This information can containing a language understood by the user. This information can
be automatically learned via call signaling or be manually set per be automatically learned via call signaling or be manually set per
participant. participant.
5.6.5 <cascaded-focus> 5.6.5. <cascaded-focus>
This element contains a conference URI (different from the main This element contains a conference URI (different from the main
conference URI) for users that are connected to the main conference conference URI) for users that are connected to the main conference
as a result of focus cascading. In accordance with the SIP as a result of focus cascading. In accordance with the SIP
conferencing framework [16], this package allows for representation Conferencing Framework [16], this package allows for representation
of peer-to-peer (i.e. "flat") focus cascading only. The actual of peer-to-peer (i.e., "flat") focus cascading only. The actual
cascading graph can not be deduced from the information provided in cascading graph can not be deduced from the information provided in
the package alone. Advanced applications can construct the graph by the package alone. Advanced applications can construct the graph by
subscribing to both this package and the Dialog Package [23] of each subscribing to both this package and the Dialog Package [23] of each
cascaded focus and correlating the relevant information. cascaded focus and correlating the relevant information.
5.6.6 <endpoint> 5.6.6. <endpoint>
By including one or more <endpoint> elements under a parent <user> By including one or more <endpoint> elements under a parent <user>
element, the server can provide the desired level of detail element, the server can provide the desired level of detail
(including the state, media streams, and access information) about (including the state, media streams, and access information) about
the user's devices and signaling sessions taking part in the the user's devices and signaling sessions taking part in the
conference. conference.
In a conferencing system where authentication is performed per In a conferencing system where authentication is performed per
endpoint (rather than per user), the focus can be unaware of the endpoint (rather than per user), the focus can be unaware of the
logical association of multiple endpoints under a common user. In logical association of multiple endpoints under a common user. In
this case, each endpoint will appear as a separate <user> with its this case, each endpoint will appear as a separate <user> with its
own <endpoint> sub-element(s) in the conference document. own <endpoint> sub-element(s) in the conference document.
In a different case, the focus may choose to shield the information In a different case, the focus may choose to shield the information
about the participant's multiple endpoints and signaling sessions about the participant's multiple endpoints and signaling sessions
from other subscribers altogether (due to privacy policies, for from other subscribers altogether (e.g., due to privacy policies).
example). To do so, the focus MAY aggregate the multiple signaling To do so, the focus MAY aggregate the multiple signaling sessions'
sessions' information under a single <endpoint> element. Note that information under a single <endpoint> element. Note that in this
in this case, the detailed call signaling information (represented by case, the detailed call signaling information (represented by
<call-info> sub-element) will not be included. <call-info> sub-element) will not be included.
5.7 <endpoint> 5.7. <endpoint>
This section describes the <endpoint> element in more detail. This section describes the <endpoint> element in more detail.
The following attributes are defined for <endpoint> element: The following attributes are defined for the <endpoint> element:
entity: The server MUST generate the 'entity' key for each <endpoint> entity: The server MUST generate the 'entity' key for each
element included under the parent <user>, such as its value is <endpoint> element included under the parent <user>, such that its
unique in the user context. In SIP terms, this can be the Contact value is unique in the user context. In SIP terms, this can be
URI, GRUU, etc. the Contact URI, GRUU, etc.
state: This attribute indicates whether the element contains the state: This attribute indicates whether the element contains the
whole endpoint information ("full"), only the information that has whole endpoint information ("full") or only the information that
changed since the previous document ("partial"), or the endpoint has changed since the previous document ("partial"), or whether
has been removed from the conference ("deleted"). the endpoint has been removed from the conference ("deleted").
The following child elements are defined for <endpoint> element: The following child elements are defined for the <endpoint> element:
5.7.1 <display-text> 5.7.1. <display-text>
This element contains the display text for the endpoint. This element contains the display text for the endpoint.
5.7.2 <referred> 5.7.2. <referred>
This element contains information about the user whose action This element contains information about the user whose action
resulted in this endpoint being brought into the conference (e.g. the resulted in this endpoint being brought into the conference (e.g.,
SIP user identified by this URI sent a REFER to the focus). It MAY the SIP user identified by this URI sent a REFER to the focus). It
contain the following sub-elements: MAY contain the following sub-elements:
when: This element of the XML dateTime type contains the date and when: This element of the XML dateTime type contains the date and
time that the endpoint was referred to the conference and SHOULD time that the endpoint was referred to the conference and SHOULD
be expressed in Coordinated Universal Time (UTC) format. For be expressed in Coordinated Universal Time (UTC) format. For
example, example,
<when>2005-03-04T20:00:00Z</when> <when>2005-03-04T20:00:00Z</when>
reason: This element contains the reason the endpoint was referred to reason: This element contains the reason the endpoint was referred
the conference. It is RECOMMENDED to include the information in to the conference. Including the information in the format
the format defined by RFC 3326 [12]. For example, defined by RFC 3326 [12] is RECOMMENDED. For example,
<reason>Reason: SIP;text="Ad-hoc Invitation"</reason> <reason>Reason: SIP;text="Ad-hoc Invitation"</reason>
by: This element contains the URI of the entity which caused the by: This element contains the URI of the entity that caused the
endpoint to be referred to the conference. In SIP case, it will endpoint to be referred to the conference. In the case of SIP, it
be populated from the Referred-By header defined in RFC 3892 [15]. will be populated from the Referred-By header defined in RFC 3892
[15].
5.7.3 <status> 5.7.3. <status>
This element contains the status of the endpoint, and can assume the This element contains the status of the endpoint and can assume the
following values: following values:
connected: The endpoint is a participant in the conference. connected: The endpoint is a participant in the conference.
Depending on the media policies, he/she can send and receive media Depending on the media policies, he/she can send and receive media
to and from other participants. to and from other participants.
disconnected: The endpoint is not a participant in the conference and disconnected: The endpoint is not a participant in the conference,
no active dialog exists between the endpoint and the focus. and no active dialog exists between the endpoint and the focus.
on-hold: Active signaling dialog exists between an endpoint and a on-hold: Active signaling dialog exists between an endpoint and a
focus, but endpoint is "on-hold" for this conference, i.e. he/she focus, but endpoint is "on-hold" for this conference, i.e., he/she
is neither "hearing" the conference mix, nor is his/her media is neither "hearing" the conference mix nor is his/her media being
being mixed in the conference. As an example, the endpoint has mixed in the conference. As an example, the endpoint has asked to
asked to join the conference using SIP, but his/her participation join the conference using SIP, but his/her participation is
is pending based on moderator approval. In the meantime he/she is pending based on moderator approval. In the meantime, he/she is
hearing music-on-hold or some other kind of related content. hearing music-on-hold or some other kind of related content.
muted-via-focus: Active signaling dialog exists between an endpoint muted-via-focus: Active signaling dialog exists between an endpoint
and a focus and the endpoint can "listen" to the conference, but and a focus and the endpoint can "listen" to the conference, but
endpoint's media is not being mixed into the conference. Note the endpoint's media is not being mixed into the conference. Note
that sometimes a subset of endpoint media streams can be muted by that sometimes a subset of endpoint media streams can be muted by
focus (such as poor quality video) while others (such as voice or focus (such as poor-quality video) while others (such as voice or
IM) can still be active. In this case, it is RECOMMENDED that the IM) can still be active. In this case, it is RECOMMENDED that the
"aggregated" endpoint connectivity <status> reflects the status of "aggregated" endpoint connectivity <status> reflects the status of
the most active media. the most active media.
pending: Endpoint is not yet in the session, but it is anticipated pending: Endpoint is not yet in the session, but it is anticipated
that he/she will join in the near future. that he/she will join in the near future.
alerting: A PSTN ALERTING or SIP 180 Ringing was returned for the alerting: A Public Switched Telephone Network (PSTN) ALERTING or SIP
outbound call, endpoint is being alerted. 180 Ringing was returned for the outbound call; endpoint is being
alerted.
dialing-in: Endpoint is dialing into the conference, not yet in the dialing-in: Endpoint is dialing into the conference, not yet in the
roster (probably being authenticated). roster (probably being authenticated).
dialing-out: Focus has dialed out to connect the endpoint to the dialing-out: Focus has dialed out to connect the endpoint to the
conference, but the endpoint is not yet in the roster (probably conference, but the endpoint is not yet in the roster (probably
being authenticated). being authenticated).
disconnecting: Focus is in the process of disconnecting the endpoint disconnecting: Focus is in the process of disconnecting the endpoint
(e.g., in SIP a DISCONNECT or BYE was sent to the endpoint). (e.g., in SIP a DISCONNECT or BYE was sent to the endpoint).
Note that the defined transient statuses (e.g., disconnecting, Note that the defined transient statuses (e.g., disconnecting,
alerting, etc.) could generate a lot of traffic. Therefore alerting, etc.) could generate a lot of traffic. Therefore,
implementations MAY choose to generate notifications on these implementations MAY choose to generate notifications on these
statuses to certain participants only or not generate them at all, statuses to certain participants only or not generate them at all,
subject to local policy. subject to local policy.
5.7.4 <joining-method> 5.7.4. <joining-method>
This element contains the method by which the endpoint joined the This element contains the method by which the endpoint joined the
conference, and can assume the following values: conference and can assume the following values:
dialed-in: The endpoint dialed into the conference (e.g., in SIP sent dialed-in: The endpoint dialed into the conference (e.g., in a SIP
INVITE to the focus), which resulted in successful dialog sent INVITE to the focus), which resulted in successful dialog
establishment. establishment.
dialed-out: The focus has brought the endpoint into the dialed-out: The focus has brought the endpoint into the conference
conference(e.g., in SIP the focus sent a successful INVITE to the (e.g., in SIP, the focus sent a successful INVITE to the
endpoint). endpoint).
focus-owner: The endpoint is the focus for this conference. This focus-owner: The endpoint is the focus for this conference. This
status is used only when a participant's UA acts as a conference status is used only when a participant's UA acts as a conference
focus. focus.
5.7.5 <joining-info> 5.7.5. <joining-info>
This element contains information about how the endpoint joined and This element contains information about how the endpoint joined and
MAY contain the following sub-elements: MAY contain the following sub-elements:
when: This element of the XML dateTime type contains the date and when: This element of the XML dateTime type contains the date and
time that the endpoint joined the conference and SHOULD be time that the endpoint joined the conference and SHOULD be
expressed in Coordinated Universal Time (UTC). expressed in Coordinated Universal Time (UTC).
reason: This element contains the reason the endpoint joined the reason: This element contains the reason the endpoint joined the
conference. It is RECOMMENDED to include the information in the conference. Including the information in the format defined by
format defined by RFC 3326 [12]. For example, RFC 3326 [12] is RECOMMENDED. For example,
<reason>Reason: SIP;text="Ad-hoc Invitation"</reason> <reason>Reason: SIP;text="Ad-hoc Invitation"</reason>
by: This element contains the URI of the entity which caused the by: This element contains the URI of the entity that caused the
endpoint to join the conference. endpoint to join the conference.
5.7.6 <disconnection-method> 5.7.6. <disconnection-method>
This element contains the method by which the endpoint departed the This element contains the method by which the endpoint departed the
conference, and can assume the following values: conference and can assume the following values:
departed: In SIP, the endpoint sent a BYE, thus leaving the departed: In SIP, the endpoint sent a BYE, thus leaving the
conference. conference.
booted: In SIP, the endpoint was sent a BYE by the focus, ejecting booted: In SIP, the endpoint was sent a BYE by the focus, ejecting
him/her out of the conference. Alternatively, the endpoint tried him/her out of the conference. Alternatively, the endpoint tried
to dial into to conference but was rejected by the focus due to to dial into the conference but was rejected by the focus due to
local policy. local policy.
failed: In SIP, the server tried to bring the endpoint into the failed: In SIP, the server tried to bring the endpoint into the
conference, but its attempt to contact the specific endpoint conference, but its attempt to contact the specific endpoint
resulted in a non-200 class final response. Alternatively, the resulted in a non-200 class final response. Alternatively, the
endpoint tried to dial into the conference without success due to endpoint tried to dial into the conference without success due to
technical reasons. technical reasons.
busy: In SIP, the server tried to bring the endpoint into the busy: In SIP, the server tried to bring the endpoint into the
conference, but its attempt to contact the specific endpoint conference, but its attempt to contact the specific endpoint
resulted in 486 "Busy Here" final response. Alternatively, the resulted in a 486 "Busy Here" final response. Alternatively, the
endpoint tried to dial into the conference but the focus responded endpoint tried to dial into the conference but the focus responded
with 486 response. with 486 response.
5.7.7 <disconnection-info> 5.7.7. <disconnection-info>
This element contains information about the endpoint's departure from This element contains information about the endpoint's departure from
the conference and MAY contain the following sub-elements: the conference and MAY contain the following sub-elements:
when: This element of the XML dateTime type contains the date and when: This element of the XML dateTime type contains the date and
time that the endpoint departed the conference and SHOULD be time that the endpoint departed the conference and SHOULD be
expressed in Coordinated Universal Time (UTC). expressed in Coordinated Universal Time (UTC).
reason: This element contains the reason the endpoint departed the reason: This element contains the reason the endpoint departed the
conference. When known and meaningful, it is RECOMMENDED to conference. When known and meaningful, including the information
include the information as conveyed/reported by the call signaling as conveyed/reported by the call signaling in the format defined
in the format defined by RFC 3326 [12]. For example, by RFC 3326 [12] is RECOMMENDED. For example,
<reason>Reason: SIP;cause=415;text="Unsupported Media Type"</reason> <reason>Reason: SIP;cause=415;text="Unsupported Media Type"</reason>
by: This element contains the URI of the entity which caused the by: This element contains the URI of the entity that caused the
endpoint to depart the conference. endpoint to depart the conference.
5.7.8 <media> 5.7.8. <media>
This element contains information about a single media stream and is This element contains information about a single media stream and is
included for each media stream being established between the focus included for each media stream being established between the focus
and the <endpoint>. The media stream definition can be found in SDP and the <endpoint>. The media stream definition can be found in SDP
[3]. [3].
Note that if the <call-info> sub-element of the endpoint is not Note that if the <call-info> sub-element of the endpoint is not
included in the document by the server, it is possible that the media included in the document by the server, it is possible that the media
streams listed under the common <endpoint> were established by streams listed under the common <endpoint> were established by
separate signaling sessions. separate signaling sessions.
5.7.9 <call-info> 5.7.9. <call-info>
The <call-info> element provides detailed call signaling information The <call-info> element provides detailed call signaling information
for a call being maintained between the participant and the focus. for a call being maintained between the participant and the focus.
Privacy policies MUST be consulted before revealing this information Privacy policies MUST be consulted before revealing this information
to other participants. to other participants.
The <sip> sub-element contains the SIP dialog identifier of the The <sip> sub-element contains the SIP dialog identifier of the
endpoint's dialog with the focus. The element includes sub-elements endpoint's dialog with the focus. The element includes sub-elements
<display-text>, <call-id>, <to-tag>, <from-tag>. <display-text>, <call-id>, <to-tag>, <from-tag>.
In future, the <call-info> element can be expanded to include call In future, the <call-info> element can be expanded to include call
signaling protocol information for other protocols besides SIP. signaling protocol information for other protocols besides SIP.
5.8 <media> 5.8. <media>
This section describes the <media> element in more detail. This section describes the <media> element in more detail.
A single 'id' attribute is defined for this element. This is the A single 'id' attribute is defined for this element. This is the
media stream identifier being generated by the server such as its media stream identifier being generated by the server such that its
value is unique in the endpoint context. This attribute is the key value is unique in the endpoint context. This attribute is the key
to refer to a particular media stream in the conference document. to refer to a particular media stream in the conference document.
The following child elements are defined for <media>: The following child elements are defined for <media>:
5.8.1 <display-text> 5.8.1. <display-text>
This element contains the display text for the media stream. The This element contains the display text for the media stream. The
value of this element corresponds to the SDP description media value of this element corresponds to the SDP description media
attribute ("i") defined in SDP [3]. attribute ("i") defined in SDP [3].
5.8.2 <type> 5.8.2. <type>
This element contains the media type for the media stream. The value This element contains the media type for the media stream. The value
of this element MUST be one of the values registered for "media" of of this element MUST be one of the values registered for "media" of
SDP [3] and its later revision(s). SDP [3] and its later revision(s).
5.8.3 <label> 5.8.3. <label>
The <label> element carries a unique identifier for this stream among The <label> element carries a unique identifier for this stream among
all streams in the conference and is assigned by the focus. The all streams in the conference and is assigned by the focus. The
value of this element will typically correspond to the SDP "label" value of this element will typically correspond to the SDP "label"
media attribute defined in [17] and is exchanged between a media attribute defined in [17] and is exchanged between a
participant and a focus over the signaling connection between them. participant and a focus over the signaling connection between them.
If the <available-media> information (described in Section 5.3.4) is If the <available-media> information (described in Section 5.3.4) is
included in the conference document, the value of this element MUST included in the conference document, the value of this element MUST
be equal to the 'label' value of the corresponding media stream be equal to the 'label' value of the corresponding media stream
<entry> in the <available-media> container. <entry> in the <available-media> container.
5.8.4 <src-id> 5.8.4. <src-id>
The <src-id> element, if applicable, carries the information about The <src-id> element, if applicable, carries the information about
the actual source of the media. For example, for Real-Time Transport the actual source of the media. For example, for Real-time Transport
Protocol (RTP) / Real-Time Control Protocol (RTCP) [13] media Protocol (RTP) / RTP Control Protocol (RTCP) [13] media streams, the
streams, the value MUST contain the synchronization source (SSRC) value MUST contain the synchronization source (SSRC) identifier value
identifier value generated by the endpoint for the stream it sends. generated by the endpoint for the stream it sends.
When an RTP mixer generates a contributing source (CSRC) identifiers' When an RTP mixer generates a contributing source (CSRC) identifiers'
list according to RTP/RTCP [13], it inserts a list of the SSRC list according to RTP/RTCP [13], it inserts a list of the SSRC
identifiers of the sources that contributed to the generation of a identifiers of the sources that contributed to the generation of a
particular packet into the RTP header of that packet. A quote from particular packet into the RTP header of that packet. A quote from
RFC 3550: "An example application is audio conferencing where a mixer RFC 3550 [13] explains as follows: "An example application is audio
indicates all the talkers whose speech was combined to produce the conferencing where a mixer indicates all the talkers whose speech was
outgoing packet, allowing the receiver to indicate the current combined to produce the outgoing packet, allowing the receiver to
talker, even though all the audio packets contain the same SSRC indicate the current talker, even though all the audio packets
identifier (that of the mixer)." contain the same SSRC identifier (that of the mixer)."
If an RTP mixer compliant to the above is used, participants can If an RTP mixer compliant to the above is used, participants can
perform an SSRC to user mapping and identify "a current speaker". perform an SSRC to user mapping and identify "a current speaker".
5.8.5 <status> 5.8.5. <status>
The element <status> indicates the status in both directions of the The element <status> indicates the status in both directions of the
media stream and has the values "sendrecv", "sendonly", "recvonly", media stream and has the values "sendrecv", "sendonly", "recvonly",
or "inactive" as defined in SDP [3] and its later revision(s). Note or "inactive" as defined in SDP [3] and its later revision(s). Note
that value specifies the direction from the participant's point of that value specifies the direction from the participant's point of
view. For example, a muted participant's stream will have the value view. For example, a muted participant's stream will have the value
of "recvonly". of "recvonly".
5.9 Sidebars 5.9. Sidebars
If a participant in the main conference joins a sidebar, a new <user> If a participant in the main conference joins a sidebar, a new <user>
element representing the user is created either as a part of a element representing the user is created either as a part of a
separate sub-conference referenced from the <sidebars-by-ref> element separate sub-conference referenced from the <sidebars-by-ref> element
or under one of the <sidebar-by-val> elements as described below. or under one of the <sidebars-by-val> elements as described below.
Note that the <user> in the main roster is not being deleted, but its Note that the <user> in the main roster is not being deleted, but its
media statuses can be updated to reflect the effect being caused by media statuses can be updated to reflect the effect being caused by
his/her participation in the sidebar. The display of this his/her participation in the sidebar. The display of this
information can vary among subscribers to the same conference information can vary among subscribers to the same conference
information, subject to local policies and to the subscriber role information, subject to local policies and to the subscriber role
both in the sidebar and in the main conference. both in the sidebar and in the main conference.
5.9.1 <sidebars-by-ref> 5.9.1. <sidebars-by-ref>
This element contains a set of <entry> child elements each containing This element contains a set of <entry> child elements, each
a sidebar conference URI. The recipient of the information can then containing a sidebar conference URI. The recipient of the
subscribe to sidebar information independently from the main information can then subscribe to sidebar information independently
conference package subscription. from the main conference package subscription.
5.9.2 <sidebar-by-val> 5.9.2. <sidebars-by-val>
This element contains a set of <entry> child elements each containing This element contains a set of <entry> child elements, each
information about a single sidebar. By using this element of containing information about a single sidebar. By using this element
conference-type, the server can include a full or a partial of conference-type, the server can include a full or partial
description of each sidebar (as a sub-conference) in the body of the description of each sidebar (as a sub-conference) in the body of the
main conference document. main conference document.
6. XML Schema 6. XML Schema
<?xml version="1.0" encoding="UTF-8" ?> <?xml version="1.0" encoding="UTF-8" ?>
<xs:schema <xs:schema
targetNamespace="urn:ietf:params:xml:ns:conference-info" targetNamespace="urn:ietf:params:xml:ns:conference-info"
xmlns:tns="urn:ietf:params:xml:ns:conference-info" xmlns:tns="urn:ietf:params:xml:ns:conference-info"
xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xs="http://www.w3.org/2001/XMLSchema"
skipping to change at page 30, line 26 skipping to change at page 30, line 25
<xs:element name="purpose" type="xs:string" <xs:element name="purpose" type="xs:string"
minOccurs="0"/> minOccurs="0"/>
<xs:element name="modified" type="execution-type" <xs:element name="modified" type="execution-type"
minOccurs="0"/> minOccurs="0"/>
<xs:any namespace="##other" processContents="lax" <xs:any namespace="##other" processContents="lax"
minOccurs="0" maxOccurs="unbounded"/> minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence> </xs:sequence>
<xs:anyAttribute namespace="##other" processContents="lax"/> <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType> </xs:complexType>
<!-- <!--
KEWORDS TYPE KEYWORDS TYPE
--> -->
<xs:simpleType name="keywords-type"> <xs:simpleType name="keywords-type">
<xs:list itemType="xs:string"/> <xs:list itemType="xs:string"/>
</xs:simpleType> </xs:simpleType>
<!-- <!--
USERS TYPE USERS TYPE
--> -->
<xs:complexType name="users-type"> <xs:complexType name="users-type">
<xs:sequence> <xs:sequence>
<xs:element name="user" type="user-type" <xs:element name="user" type="user-type"
skipping to change at page 35, line 7 skipping to change at page 35, line 7
minOccurs="0" maxOccurs="unbounded"/> minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence> </xs:sequence>
<xs:attribute name="state" type="state-type" <xs:attribute name="state" type="state-type"
use="optional" default="full"/> use="optional" default="full"/>
<xs:anyAttribute namespace="##other" processContents="lax"/> <xs:anyAttribute namespace="##other" processContents="lax"/>
</xs:complexType> </xs:complexType>
</xs:schema> </xs:schema>
7. Examples 7. Examples
7.1 Basic Example 7.1. Basic Example
The following is an example of a full conference information The following is an example of a full conference information
document: document:
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<conference-info <conference-info
xmlns="urn:ietf:params:xml:ns:conference-info" xmlns="urn:ietf:params:xml:ns:conference-info"
entity="sips:conf233@example.com" entity="sips:conf233@example.com"
state="full" version="1"> state="full" version="1">
<!-- <!--
skipping to change at page 36, line 47 skipping to change at page 36, line 46
<type>audio</type> <type>audio</type>
<label>34567</label> <label>34567</label>
<src-id>534232</src-id> <src-id>534232</src-id>
<status>sendrecv</status> <status>sendrecv</status>
</media> </media>
</endpoint> </endpoint>
</user> </user>
</users> </users>
</conference-info> </conference-info>
7.2 Rich Example 7.2. Rich Example
The following is an example of a partial conference information The following is an example of a partial conference information
document. In this example, there are 32 participants in a voice document. In this example, there are 32 participants in a voice
conference. The user Bob has been ejected from the conference by conference. The user Bob has been ejected from the conference by
Mike due to bad voice quality. Note that there are three sidebars in Mike due to bad voice quality. Note that there are three sidebars in
the conference, two are referenced just by their sidebar URIs and the conference; two are referenced just by their sidebar URIs, and
information about the third sidebar is included in this notification. information about the third sidebar is included in this notification.
Also note that while this conference offers both audio and video Also note that while this conference offers both audio and video
capabilities, only audio is currently in use. capabilities, only audio is currently in use.
<?xml version="1.0" encoding="UTF-8"?> <?xml version="1.0" encoding="UTF-8"?>
<conference-info <conference-info
xmlns="urn:ietf:params:xml:ns:conference-info" xmlns="urn:ietf:params:xml:ns:conference-info"
entity="sips:conf233@example.com" entity="sips:conf233@example.com"
state="partial" version="5"> state="partial" version="5">
<!-- <!--
skipping to change at page 40, line 37 skipping to change at page 40, line 34
<user entity="sip:mark@example.com"/> <user entity="sip:mark@example.com"/>
<user entity="sip:dan@example.com"/> <user entity="sip:dan@example.com"/>
</users> </users>
</entry> </entry>
</sidebars-by-val> </sidebars-by-val>
</conference-info> </conference-info>
8. Security Considerations 8. Security Considerations
Subscriptions to conference state information can reveal very Subscriptions to conference state information can reveal very
sensitive information. For this reason, it is RECOMMENDED a focus sensitive information. For this reason, it is RECOMMENDED that a
use a strong means for authentication, conference information focus use a strong means for authentication and conference
protection, and apply comprehensive authorization rules when using information protection and that it apply comprehensive authorization
the conference notification mechanism defined in this document. The rules when using the conference notification mechanism defined in
following sections will discuss each of these aspects in more detail. this document. The following sections will discuss each of these
aspects in more detail.
8.1 Connection Security 8.1. Connection Security
It is RECOMMENDED that a focus authenticate a conference package It is RECOMMENDED that a focus authenticate a conference package
subscriber using the normal SIP authentication mechanisms, such as subscriber using the normal SIP authentication mechanisms, such as
Digest as defined in Section 22 of RFC 3261 [8]. Digest as defined in Section 22 of RFC 3261 [8].
The mechanism used for conveying the conference information MUST The mechanism used for conveying the conference information MUST
ensure integrity and SHOULD ensure confidentially of the information. ensure integrity and SHOULD ensure confidentially of the information.
In order to achieve these, an end-to-end SIP encryption mechanism, In order to achieve these, an end-to-end SIP encryption mechanism,
such as S/MIME described in Section 26.2.4 of RFC 3261 [8], SHOULD be such as S/MIME described in Section 26.2.4 of RFC 3261 [8], SHOULD be
used. used.
If strong end-to-end security means (such as above) is not available, If a strong end-to-end security means (such as above) is not
it is RECOMMENDED that a focus use mutual hop-by-hop TLS available, it is RECOMMENDED that a focus use mutual hop-by-hop
authentication and encryption mechanisms described in Section 26.2.2 Transport Layer Security (TLS) authentication and encryption
"SIPS URI Scheme" and Section 26.3.2.2 "Interdomain Requests" of RFC mechanisms described in Section 26.2.2 "SIPS URI Scheme" and Section
3261 [8]. 26.3.2.2 "Interdomain Requests" of RFC 3261 [8].
8.2 Authorization Considerations 8.2. Authorization Considerations
Generally speaking, conference applications are very concerned about Generally speaking, conference applications are very concerned about
authorization decisions. Mechanisms for establishing and enforcing authorization decisions. Mechanisms for establishing and enforcing
such authorization rules are a central concept throughout the SIP such authorization rules are a central concept throughout the SIP
conferencing framework [16]. Because most of the information about a Conferencing Framework [16]. Because most of the information about a
conference can be presented using the conference package, many of the conference can be presented using the conference package, many of the
authorization rules directly apply to this specification. As a authorization rules directly apply to this specification. As a
result, a notification server MUST be capable of generating distinct result, a notification server MUST be capable of generating distinct
conference information views to different subscribers, subject to a conference information views to different subscribers, subject to a
subscriber's role in a conference, personal access rights, etc. - all subscriber's role in a conference, personal access rights, etc. - all
subject to local authorization policies and rules. subject to local authorization policies and rules.
Since a focus provides participant identity information using this Since a focus provides participant identity information using this
event package, participant privacy needs to be taken into account. A event package, participant privacy needs to be taken into account. A
focus MUST support requests by participants for privacy. Privacy can focus MUST support requests by participants for privacy. Privacy can
be indicated by the conference policy - for every participant or be indicated by the conference policy - for every participant or
select participants. It can also be indicated in the session select participants. It can also be indicated in the session
signaling. In SIP this can be done using the Privacy header field signaling. In SIP, this can be done using the Privacy header field
described in RFC 3323 [11]. For a participant requesting privacy, no described in RFC 3323 [11]. For a participant requesting privacy, no
identity information SHOULD be revealed by the focus in any included identity information SHOULD be revealed by the focus in any included
URI (e.g. the Address of Record, Contact, or GRUU). For these cases, URI (e.g., the Address of Record, Contact, or GRUU). For these
the anonymous URI generation method outlined in Section 5.6 of this cases, the anonymous URI generation method outlined in Section 5.6 of
document MUST be followed. this document MUST be followed.
9. IANA Considerations 9. IANA Considerations
This document registers a SIP event package, a new MIME type, This document registers a SIP event package, a new MIME type,
application/conference-info+xml, a new XML namespace, a new XML application/conference-info+xml, a new XML namespace, and a new XML
schema, and creates a sub-registry "URI purposes" under the schema, and creates a sub-registry "URI purposes" under the existing
existing registry: http://www.iana.org/assignments/sip-parameters. registry: http://www.iana.org/assignments/sip-parameters.
9.1 conference Event Package Registration 9.1. conference Event Package Registration
This specification registers an event package, based on the This specification registers an event package, based on the
registration procedures defined in RFC 3265 [10]. The following is registration procedures defined in RFC 3265 [10]. The following is
the information required for such a registration: the information required for such a registration:
Package Name: conference Package Name: conference
Package or Template-Package: This is a package. Package or Template-Package: This is a package.
Published Document: RFC XXXX (Note to RFC Editor: Please, fill in
XXXX with the RFC number of this specification). Published Document: RFC 4575
Person to Contact: IETF SIPPING Working Group <sipping@ietf.org>, as Person to Contact: IETF SIPPING Working Group <sipping@ietf.org>, as
designated by the IESG <iesg@ietf.org> designated by the IESG <iesg@ietf.org>
9.2 application/conference-info+xml MIME Registration 9.2. application/conference-info+xml MIME Registration
MIME media type name: application MIME media type name: application
MIME subtype name: conference-info+xml MIME subtype name: conference-info+xml
Mandatory parameters: none Mandatory parameters: none
Optional parameters: Same as charset parameter application/xml as Optional parameters: Same as charset parameter application/xml as
specified in RFC 3023 [7] specified in RFC 3023 [7]
Encoding considerations: Same as encoding considerations of Encoding considerations: Same as encoding considerations of
application/xml as specified in RFC 3023 [7] application/xml as specified in RFC 3023 [7]
Security considerations: See Section 10 of RFC 3023 [7] and Section 8
of this specification Security considerations: See Section 10 of RFC 3023 [7] and
Section 8 of this specification
Interoperability considerations: none Interoperability considerations: none
Published specification: This document Published specification: This document
Applications which use this media type: This document type has been Applications which use this media type: This document type has been
used to support SIP conferencing applications used to support SIP conferencing applications
Additional Information: Additional Information:
Magic Number: None Magic Number: None
File Extension: .xml File Extension: .xml
Macintosh file type code: "TEXT" Macintosh file type code: "TEXT"
Personal and email address for further information: IETF SIPPING Personal and email address for further information: IETF SIPPING
Working Group <sipping@ietf.org>, as designated by the IESG Working Group <sipping@ietf.org>, as designated by the IESG
<iesg@ietf.org> <iesg@ietf.org>
Intended usage: COMMON Intended usage: COMMON
Author/Change controller: IETF SIPPING Working Group Author/Change controller: IETF SIPPING Working Group
<sipping@ietf.org>, as designated by the IESG <iesg@ietf.org> <sipping@ietf.org>, as designated by the IESG <iesg@ietf.org>
9.3 URN Sub-Namespace Registration for 9.3. URN Sub-Namespace Registration for
urn:ietf:params:xml:ns:conference-info urn:ietf:params:xml:ns:conference-info
This section registers a new XML namespace, as per the guidelines in This section registers a new XML namespace, as per the guidelines in
RFC 3688 [21]. RFC 3688 [21].
URI: The URI for this namespace is URI: The URI for this namespace is
urn:ietf:params:xml:ns:conference-info urn:ietf:params:xml:ns:conference-info
Registrant Contact: IETF SIPPING Working Group <sipping@ietf.org>, as
designated by the IESG <iesg@ietf.org> Registrant Contact: IETF SIPPING Working Group <sipping@ietf.org>,
as designated by the IESG <iesg@ietf.org>
XML: XML:
BEGIN BEGIN
<?xml version="1.0"?> <?xml version="1.0"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN" <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"
"http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd"> "http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"> <html xmlns="http://www.w3.org/1999/xhtml">
<head> <head>
<meta http-equiv="content-type" <meta http-equiv="content-type"
content="text/html;charset=iso-8859-1"/> content="text/html;charset=iso-8859-1"/>
<title>Conference Information Namespace</title> <title>Conference Information Namespace</title>
</head </head
<body> <body>
<h1>Namespace for Conference Information</h1> <h1>Namespace for Conference Information</h1>
<h2>urn:ietf:params:xml:ns:conference-info</h2> <h2>urn:ietf:params:xml:ns:conference-info</h2>
<p>See <a href="[[[URL of published RFC]]]">RFCXXXX</a>.</p> <p>See <a href="http://www.rfc-editor.org/rfc/rfc4575.txt">
RFC4575</a>.</p>
</body> </body>
</html> </html>
END END
9.4 XML Schema Registration 9.4. XML Schema Registration
This specification registers a schema, as per the guidelines in RFC This specification registers a schema, as per the guidelines in RFC
3688 [21]. 3688 [21].
URI: please assign URI: please assign
Registrant Contact: IETF SIPPING Working Group <sipping@ietf.org>, Registrant Contact: IETF SIPPING Working Group <sipping@ietf.org>,
as designated by the IESG <iesg@ietf.org> as designated by the IESG <iesg@ietf.org>
XML: The XML can be found as the sole content of Section 6
9.5 URI Purposes Sub-registry Establishment XML: The XML can be found as the sole content of Section 6.
This document instructs the IANA to create a new sub-registry "URI 9.5. URI Purposes Sub-registry Establishment
purposes" under the already existing registry:
The IANA has created a new sub-registry, "URI purposes", under the
already existing registry:
http://www.iana.org/assignments/sip-parameters. http://www.iana.org/assignments/sip-parameters.
The purpose of a URI is an XML element, encoded in the conference The purpose of a URI is an XML element, encoded in the conference
event package [RFC XXXX - substitute with the number assigned to this event package RFC 4575. The value of the <purpose> element indicates
draft]. The value of the <purpose> element indicates the intended the intended usage of the URI in the context of the conference event
usage of the URI in the context of the conference event package and package and is defined in Sections 5.3.1 and 5.3.2 of this
is defined in sections Section 5.3.1 and Section 5.3.2 of this
specification. specification.
This sub-registry is defined as a table that contains the following This sub-registry is defined as a table that contains the following
three columns: three columns:
Value: The token under registration Value: The token under registration
Description: A descriptive text defining the intended usage of the Description: A descriptive text defining the intended usage of the
URI URI
Document: A reference to the document defining the registration Document: A reference to the document defining the registration
This specification instructs IANA to create the table with the The IANA has created the table with the initial content as defined
initial content as defined below: below:
Value Description Document Value Description Document
------- ---------------------------------- ---------- ------- ---------------------------------- ----------
participation The URI can be used to join the [RFC XXXX] participation The URI can be used to join the [RFC 4575]
conference conference
streaming The URI can be used to access the [RFC XXXX] streaming The URI can be used to access the [RFC 4575]
streamed conference data streamed conference data
event The URI can be used to subscribe [RFC XXXX] event The URI can be used to subscribe [RFC 4575]
to the conference event package to the conference event package
recording The URI can be used to access the [RFC XXXX] recording The URI can be used to access the [RFC 4575]
recorded conference data recorded conference data
web-page The URI can be used to access a [RFC XXXX] web-page The URI can be used to access a [RFC 4575]
web page that contains additional web page that contains additional
information of the conference information of the conference
New values of the "URI purposes" are registered by the IANA and are New values of the "URI purposes" are registered by the IANA and are
specification required according to the definition of RFC 2434 [4]. specification required according to the definition of RFC 2434 [4].
The IANA Considerations section of the specification MUST include the The IANA Considerations section of the specification MUST include the
following information: following information:
Value: The value of the <purpose> element to be registered Value: The value of the <purpose> element to be registered
Description: A short description of the intended usage of the URI Description: A short description of the intended usage of the URI
10. Acknowledgements 10. Acknowledgements
The authors would like to thank Dan Petrie, Sean Olson, Alan The authors would like to thank Dan Petrie, Sean Olson, Alan
Johnston, Rohan Mahy, Cullen Jennings, Brian Rosen, Roni Even, and Johnston, Rohan Mahy, Cullen Jennings, Brian Rosen, Roni Even, and
Miguel Garcia for their comments and inputs. Miguel Garcia for their comments and inputs.
11. References 11. References
skipping to change at page 45, line 5 skipping to change at page 45, line 17
Description: A short description of the intended usage of the URI Description: A short description of the intended usage of the URI
10. Acknowledgements 10. Acknowledgements
The authors would like to thank Dan Petrie, Sean Olson, Alan The authors would like to thank Dan Petrie, Sean Olson, Alan
Johnston, Rohan Mahy, Cullen Jennings, Brian Rosen, Roni Even, and Johnston, Rohan Mahy, Cullen Jennings, Brian Rosen, Roni Even, and
Miguel Garcia for their comments and inputs. Miguel Garcia for their comments and inputs.
11. References 11. References
11.1 Normative References 11.1. Normative References
[1] Bradner, S., "Key words for use in RFCs to Indicate Requirement [1] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997. Levels", BCP 14, RFC 2119, March 1997.
[2] Moats, R., "URN Syntax", RFC 2141, May 1997. [2] Moats, R., "URN Syntax", RFC 2141, May 1997.
[3] Handley, M. and V. Jacobson, "SDP: Session Description [3] Handley, M., Jacobson, V. and C. Perkins, "SDP: Session
Protocol", RFC 2327, April 1998. Description Protocol", RFC 4566, July 2006.
[4] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA [4] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA
Considerations Section in RFCs", BCP 26, RFC 2434, Considerations Section in RFCs", BCP 26, RFC 2434, October
October 1998. 1998.
[5] Eastlake, D. and A. Panitz, "Reserved Top Level DNS Names", [5] Eastlake 3rd, D. and A. Panitz, "Reserved Top Level DNS Names",
BCP 32, RFC 2606, June 1999. BCP 32, RFC 2606, June 1999.
[6] Moats, R., "A URN Namespace for IETF Documents", RFC 2648, [6] Moats, R., "A URN Namespace for IETF Documents", RFC 2648,
August 1999. August 1999.
[7] Murata, M., St. Laurent, S., and D. Kohn, "XML Media Types", [7] Murata, M., St. Laurent, S., and D. Kohn, "XML Media Types",
RFC 3023, January 2001. RFC 3023, January 2001.
[8] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., [8] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP:
Session Initiation Protocol", RFC 3261, June 2002. Session Initiation Protocol", RFC 3261, June 2002.
[9] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model with [9] Rosenberg, J. and H. Schulzrinne, "An Offer/Answer Model with
Session Description Protocol (SDP)", RFC 3264, June 2002. Session Description Protocol (SDP)", RFC 3264, June 2002.
[10] Roach, A., "Session Initiation Protocol (SIP)-Specific Event [10] Roach, A.B., "Session Initiation Protocol (SIP)-Specific Event
Notification", RFC 3265, June 2002. Notification", RFC 3265, June 2002.
[11] Peterson, J., "A Privacy Mechanism for the Session Initiation [11] Peterson, J., "A Privacy Mechanism for the Session Initiation
Protocol (SIP)", RFC 3323, November 2002. Protocol (SIP)", RFC 3323, November 2002.
[12] Schulzrinne, H., Oran, D., and G. Camarillo, "The Reason Header [12] Schulzrinne, H., Oran, D., and G. Camarillo, "The Reason Header
Field for the Session Initiation Protocol (SIP)", RFC 3326, Field for the Session Initiation Protocol (SIP)", RFC 3326,
December 2002. December 2002.
[13] Schulzrinne, H., Casner, S., Frederick, R., and V. Jacobson, [13] Schulzrinne, H., Casner, S., Frederick, R., and V. Jacobson,
"RTP: A Transport Protocol for Real-Time Applications", STD 64, "RTP: A Transport Protocol for Real-Time Applications", STD 64,
RFC 3550, July 2003. RFC 3550, July 2003.
[14] Yergeau, F., "UTF-8, a transformation format of ISO 10646", [14] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD
STD 63, RFC 3629, November 2003. 63, RFC 3629, November 2003.
[15] Sparks, R., "The Session Initiation Protocol (SIP) Referred-By [15] Sparks, R., "The Session Initiation Protocol (SIP) Referred-By
Mechanism", RFC 3892, September 2004. Mechanism", RFC 3892, September 2004.
[16] Rosenberg, J., "A Framework for Conferencing with the Session [16] Rosenberg, J., "A Framework for Conferencing with the Session
Initiation Protocol", Initiation Protocol (SIP)", RFC 4353, February 2006.
draft-ietf-sipping-conferencing-framework-05 (work in
progress), May 2005.
[17] Levin, O. and G. Camarillo, "The SDP (Session Description [17] Levin, O. and G. Camarillo, "The Session Description Protocol
Protocol) Label Attribute", (SDP) Label Attribute", RFC 4574, August 2006.
draft-ietf-mmusic-sdp-media-label-01 (work in progress),
January 2005.
11.2 Informative References 11.2. Informative References
[18] Schulzrinne, H., Rao, A., and R. Lanphier, "Real Time Streaming [18] Schulzrinne, H., Rao, A., and R. Lanphier, "Real Time Streaming
Protocol (RTSP)", RFC 2326, April 1998. Protocol (RTSP)", RFC 2326, April 1998.
[19] Schulzrinne, H., "The tel URI for Telephone Numbers", RFC 3966, [19] Schulzrinne, H., "The tel URI for Telephone Numbers", RFC 3966,
December 2004. December 2004.
[20] Levin, O., "H.323 Uniform Resource Locator (URL) Scheme [20] Levin, O., "H.323 Uniform Resource Locator (URL) Scheme
Registration", RFC 3508, April 2003. Registration", RFC 3508, April 2003.
[21] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, [21] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
January 2004. January 2004.
[22] Saint-Andre, P., "A Uniform Resource Identifier (URI) Scheme [22] Saint-Andre, P., "A Uniform Resource Identifier (URI) Scheme
for the Extensible Messaging and Presence Protocol (XMPP)", for the Extensible Messaging and Presence Protocol (XMPP)",
draft-saintandre-xmpp-uri-08 (work in progress), December 2004. Work in Progress, December 2004.
[23] Rosenberg, J., "An INVITE Inititiated Dialog Event Package for [23] Rosenberg, J., Schulzrinne, H., and R. Mahy, "An INVITE-
the Session Initiation Protocol (SIP)", Initiated Dialog Event Package for the Session Initiation
draft-ietf-sipping-dialog-package-06 (work in progress), Protocol (SIP)", RFC 4235, November 2005.
April 2005.
[24] Rosenberg, J., "Obtaining and Using Globally Routable User [24] Rosenberg, J., "Obtaining and Using Globally Routable User
Agent (UA) URIs (GRUU) in the Session Initiation Protocol Agent (UA) URIs (GRUU) in the Session Initiation Protocol
(SIP)", draft-ietf-sip-gruu-03 (work in progress), (SIP)", Work in Progress, May 2006.
February 2005.
[25] Peterson, J. and C. Jennings, "Enhancements for Authenticated [25] Peterson, J. and C. Jennings, "Enhancements for Authenticated
Identity Management in the Session Initiation Protocol (SIP)", Identity Management in the Session Initiation Protocol (SIP)",
draft-ietf-sip-identity-05 (work in progress), May 2005. RFC 4474, August 2006.
Authors' Addresses Authors' Addresses
Jonathan Rosenberg Jonathan Rosenberg
Cisco Systems Cisco Systems
600 Lanidex Plaza 600 Lanidex Plaza
Parsippany, NJ 07054 Parsippany, NJ 07054
US US
Phone: +1 973 952-5000 Phone: +1 973 952-5000
Email: jdrosen@cisco.com EMail: jdrosen@cisco.com
URI: http://www.jdrosen.net URI: http://www.jdrosen.net
Henning Schulzrinne Henning Schulzrinne
Columbia University Columbia University
M/S 0401 M/S 0401
1214 Amsterdam Ave. 1214 Amsterdam Ave.
New York, NY 10027 New York, NY 10027
US US
Email: schulzrinne@cs.columbia.edu EMail: schulzrinne@cs.columbia.edu
URI: http://www.cs.columbia.edu/~hgs URI: http://www.cs.columbia.edu/~hgs
Orit Levin (editor) Orit Levin (editor)
Microsoft Corporation Microsoft Corporation
One Microsoft Way One Microsoft Way
Redmond, WA 98052 Redmond, WA 98052
US US
Email: oritl@microsoft.com EMail: oritl@microsoft.com
Intellectual Property Statement Full Copyright Statement
Copyright (C) The Internet Society (2006).
This document is subject to the rights, licenses and restrictions
contained in BCP 78, and except as set forth therein, the authors
retain all their rights.
This document and the information contained herein are provided on an
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OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
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pertain to the implementation or use of the technology described in pertain to the implementation or use of the technology described in
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on the procedures with respect to rights in RFC documents can be on the procedures with respect to rights in RFC documents can be
found in BCP 78 and BCP 79. found in BCP 78 and BCP 79.
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such proprietary rights by implementers or users of this such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr. http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at this standard. Please address the information to the IETF at
ietf-ipr@ietf.org. ietf-ipr@ietf.org.
Disclaimer of Validity Acknowledgement
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Copyright Statement
Copyright (C) The Internet Society (2005). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights.
Acknowledgment
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is provided by the IETF
Internet Society. Administrative Support Activity (IASA).
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