DISPATCH R. Avasarala, Ed.
Internet-Draft Motorola Inc
Intended status: Informational J. Bakker
Expires: January 28, 2010 Research In Motion Corporation
S. Saha
Mobivation
July 27, 2009
A Session Initiation Protocol (SIP) Event Package for Communication
Diversion Information in support of the Communication Diversion (CDIV)
Notification (CDIVN) CDIV service
draft-avasarala-dispatch-comm-div-notification-01.txt
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Abstract
3GPP and ETSI TISPAN are defining PSTN/ISDN simulation services and
in particular the Communication Diversion (CDIV) using IP Multimedia
(IM) core Network (CN) subsystem supplementary service. As part of
CDIV, a (SIP) Event Notification Framework-based mechanism is used
for notifying Users about diversions (re-directions or forwarding) of
their incoming communication sessions. A new event package is
proposed for allowing users to subscribe for and receive such
notifications. Users have further capability to define filters
controlling the selection, rate and content of such notifications.
This SIP event package is applicable to the IMS and may not be
applicable to the general Internet.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6
3. Applicability Statement . . . . . . . . . . . . . . . . . . . 6
4. Abbreviations and Definitions . . . . . . . . . . . . . . . . 6
4.1. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 6
4.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 6
5. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 6
6. Package Definition . . . . . . . . . . . . . . . . . . . . . . 7
6.1. Event Package Name . . . . . . . . . . . . . . . . . . . . 7
6.2. Event Package Parameters . . . . . . . . . . . . . . . . . 7
6.3. SUBSCRIBE bodies . . . . . . . . . . . . . . . . . . . . . 8
6.4. Subscription Duration . . . . . . . . . . . . . . . . . . 8
6.5. Notify bodies . . . . . . . . . . . . . . . . . . . . . . 8
6.6. Notifier Processing of SUBSCRIBE requests . . . . . . . . 9
6.6.1. Authentication . . . . . . . . . . . . . . . . . . . . 9
6.6.2. Authorization . . . . . . . . . . . . . . . . . . . . 9
6.7. Notifier Generation of NOTIFY requests . . . . . . . . . . 9
6.8. Subscriber Processing of NOTIFY Requests . . . . . . . . . 10
6.9. Handling of Forked Requests . . . . . . . . . . . . . . . 10
6.10. Rate of Notifications . . . . . . . . . . . . . . . . . . 10
6.11. State Agents . . . . . . . . . . . . . . . . . . . . . . . 10
6.12. Use of URIs to Retrieve State . . . . . . . . . . . . . . 11
7. Comm-div-info Document . . . . . . . . . . . . . . . . . . . . 11
8. Structure of Comm-div-info Format . . . . . . . . . . . . . . 11
8.1. Comm-div-info Element . . . . . . . . . . . . . . . . . . 11
8.1.1. comm-div-subs-info Element . . . . . . . . . . . . . . 11
8.1.2. Comm-div-ntfy-info Element . . . . . . . . . . . . . . 14
8.1.3. Comm-div-info-selection-criteria . . . . . . . . . . . 14
8.2. Sample Notification body . . . . . . . . . . . . . . . . . 15
8.2.1. Instance of communication diversion subscription
document . . . . . . . . . . . . . . . . . . . . . . . 16
8.2.2. Instance of communication diversion notification
document . . . . . . . . . . . . . . . . . . . . . . . 17
8.3. Schema . . . . . . . . . . . . . . . . . . . . . . . . . . 17
9. Security Considerations . . . . . . . . . . . . . . . . . . . 22
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
10.1. Communication Diversion Information Event Package
Registration . . . . . . . . . . . . . . . . . . . . . . . 23
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 23
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23
12.1. Normative References . . . . . . . . . . . . . . . . . . . 23
12.2. Informative References . . . . . . . . . . . . . . . . . . 24
Appendix A. Change log . . . . . . . . . . . . . . . . . . . . . 24
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25
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1. Introduction
3GPP is currently maintaining and specifying communication diversion
mechanisms which allow users to forward and/or redirect incoming
communications to other destinations. The intention of such
mechanisms is to provide users with sufficient flexibility to manage
their incoming communications in a better way. The most common
example is Communication Forward On Busy (CFB) where in users can
forward any incoming calls, whilst they are busy on some other call,
to their voice mail or a suitable alternative (e.g. some other user).
Similarly other variants of communication diversion are well defined
and used in practice such as Communication Forward on No Answer
(CFNA), Communication Forward Unconditional (CFU). Similarly 3GPP is
currently maintaining and specifying a mechanism for Users to
configure Communication Diversion Services ([1] and [2]) for their
incoming communications. The intention of such mechanisms is to
provide Users with sufficient flexibility to manage their incoming
communications in a better way.
However, with the increasing usage of Communication Diversion
services, users may have many different variants and configurations
active at the same time. For e.g. the user may have various CFU
services configured differently based on the time-of-the-day and the
Calling party's identity, or CFB based on the time-of-the-day. This
is possible by having various such configured diversions by
subscribing to different Communication Diversion (CDIV) services as
specified by 3GPP. Though, there has been quite active work in the
area of better customization and configuration of such Communication
Diversion mechanisms, not much attention has been paid to how the
Users can manage these services in an effective manner. With the
various advanced options and high flexibility provided, it is
possible that the User loses track of the various Communication
Diversion configurations or services they have registered for.
One of the basic ways, by which subscribers can manage a CDIV service
is to be informed of which services they have registered for. For
example, [1] and [2] allow for such indications to be received by the
subscriber, at the time of initiating an outgoing call. However,
simply showing the registered services is not sufficient, since each
service may be customized in numerous and different ways for
different criteria. For example various instantiations of CFB may be
configured for different times-of-the-day and different calling party
identities. Even if subscribers are shown information about all the
Communication Diversion services and their variants that they are
registered for, they may not be able to make sense or verify that
each of them is correct as per their *expectation*. Such a mismatch
in terms of service behavior expectation and actual execution, may
happen due to incorrect configuration on behalf of the User, which
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cannot be easily detected if there are various communication
diversion services and their different configurations for handling
incoming communications.
A probable and suitable instance, when the subscriber may easily
judge whether a communication diversion is correct, is when it
actually takes place. The subscriber is already aware of the current
conditions (time-of-day, current presence and availability etc) and
hence is in a position to decide, whether the communication diversion
which just occurred, was indeed as per their expectation. For e.g.
the subscriber wanted to diverted all incoming calls to voice-mail,
between 3.00 p.m. to 4.00 p.m. Yet, by mistake she configures the
time-duration as 3.00 to 4.00 p.m. It would be very difficult for
her to spot this error while manually reviewing her complete set of
communication diversion services, with their various configurations.
Instead, if the subscriber receives a real-time notification of any
communication diversion occurring after 4 p.m., she would be able to
immediately guess that something is 'wrong' or not as per her
intention and take corrective action. Such corrective action could
be manual verification of the specific rule which triggered the
communication diversion, wherein she will be able to spot the
*mistake* more easily.
Thus, for effective subscriber services management of multiple
configurations of various Communication Diversion services, a
notification-based mechanism may work well. Such a mechanism would
involve notifying subscribers about diversions of their incoming
communications, as and when the communication diversion happens or
with a slight delay (as per subscriber service configuration). As
such diversion-related information is conveyed almost instantly or
within a small time-frame, the subscribers can verify whether the
particular communication diversion is indeed correct at that instant
of time.
This document defines a SIP event package that allows a SIP User
Agents to subscribe to and be notified of communication diversions
enacted on their behalf. This allows subscribers to subscribe to
this event package to gather this information. When subscribing to
the event package the subscribers can control how they want to
receive such notifications, the content and rate of such
notifications. It is believed that the SIP event package defined
here is not applicable to the general Internet: it has been designed
to serve the architecture of the CDIV service. The aim of this memo
is to follow the procedure indicated in RFC 3427 [3] and to register
a new event package with event name "comm-div-info" with IANA.
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2. Terminology
In this document, the key words "MUST", "MUST NOT", "REQUIRED",
"SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY",
and "OPTIONAL" are to be interpreted as described in RFC 2119 [4] and
indicate requirement levels for compliant implementations.
3. Applicability Statement
The event package defined in this document is intended for use with
network-based application servers that provide a CDIV service
4. Abbreviations and Definitions
4.1. Abbreviations
CDIV: Communication Diversion.
CDIVN: Communication Diversion Notification.
TISPAN: Telecommunications and Internet Converged Services and
Protocols for Advanced Networking.
4.2. Definitions
Subscriber - The User Agent who has subscribed to the
Communication diversion notification service.
Diverting User - The User Agent who has configured a Communication
Diversion. This could be the User Agent who has configured the
Communication DIversion service rules in the network.
Diverted-To Entity/User - The User Agent who is the new target of
the incoming communication, post execution of any configured
Communication Diversion service.
Originating User - The User Agent who is the originator of the
incoming communication, which was initially targeted towards the
Diverting User, but finally sent to the Diverted-To User. The
Originating User is also referred to as the Caller.
5. Requirements
A comprehensive description of all the requirements that affect the
CDIV service developed by TISPAN and 3GPP and can be found in the
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3GPP web page at http://www.3gpp.org and http://www.etsi.org.
For the sake of simplicity, we briefly discuss here those
requirements that affect the solution described in this document.
These requirements can be summarized as follows:
o There must be a mechanism that allows subscriber-controlled
notification of communication diversions to the diverting user,
including the option to control which notifications the user wants
to receive and to control the rate at which notifications are
received.
o There must be a mechanism that enables filtering of notifications
of communication diversion.
o There must be a mechanism that enables triggering of notifications
of communication diversion.
o There must be a mechanism that enables selecting information to be
included in notifications of communication diversion.
These requirements lead to a solution whereby the user can indicate
to a network node his interest in receiving certain type of
notifications of communication diversion. Pushing these settings to
a network node allows the network node to conserve scarce resources
while still notifying the user of communication diversions enacting
on the user's behalf.
6. Package Definition
This section fills in the details needed for an event package as
defined in Section 4.4 of [5].
6.1. Event Package Name
The SIP Events specification requires package definitions to specify
the name of their package or template-package.
The name of this package is "comm-div-info". As specified in [5],
this value appears in the Event header present in SUBSCRIBE and
NOTIFY requests.
6.2. Event Package Parameters
The SIP Events specification [5] requires package and template-
package definitions to specify any package specific parameters of the
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Event header that are used by it.
No package specific Event header parameters are defined for this
event package.
6.3. SUBSCRIBE bodies
The SIP Events specification requires package or template-package
definitions to define the usage, if any, of bodies in SUBSCRIBE
requests.
A SUBSCRIBE for Communication Diversion event MAY contain a body.
The purpose of the body depends on its type. Subscriptions to the
Comm-div-info event package typically include a body of MIME type
"application/comm-div-info+xml".
A body of the SUBSCRIBE request with content type set to MIME type
"application/comm-div-info+xml" contains information about filtering
communication diversions, trigger communication diversion
notifications and selecting information to be included in
communication diversions notifications.
6.4. Subscription Duration
The SIP Events specification requires package definitions to define a
default value for subscription durations, and to discuss reasonable
choices for durations when they are explicitly specified.
No expiration time for subscriptions withing this package is defined
in this document. The subscriber MAY specify an expiration value in
the expires header field.
6.5. Notify bodies
The SIP Events specification requires package definitions to define a
default value for subscription durations, and to discuss reasonable
choices for durations when they are explicitly specified.
The NOTIFY message contains bodies. This body is a format listed in
the Accept header field of the SUBSCRIBE request or a package
specific default format if the Accept header field was omitted from
the SUBSCRIBE request.
In this event package, the body of the notification contains comm-
div-info information when the diversion notifications occur. See
Section 8.
All subscribers and notifiers of the "comm-div-info" event package
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MUST support the "application/comm-div-info+xml" data format
described in Section 8. The SUBSCRIBE request MAY contain an Accept
header field. If no such header field is present, it has a default
value of "application/comm-div-info+xml" (assuming Event header has a
value of "comm-div-info"). If the Accept header field is present, it
MUST contain the value "application/comm-div-info+xml".
6.6. Notifier Processing of SUBSCRIBE requests
The contents of a document containing comm-div-info information can
contain sensitive information that can reveal some privacy
information. Therefore, such comm-div-info documents MUST only be
sent to authorized subscribers. In order to determine if a
subscription originates in an authorized user, the subscriber MUST be
authenticated as described in Section 6.6.1 and then the user MUST be
authorized to be a subscriber as described in Section 6.6.2.
6.6.1. Authentication
Notifiers MUST authenticate all subscription requests. This
authentication can be done using any of the mechanisms defined in [6]
and other authentication extensions.
6.6.2. Authorization
Once authenticated, the notifier makes an authorization decision. A
notifier MUST NOT accept a subscription unless authorization has been
provided by the user. The means by which authorization are provided
are outside the scope of this document. Authorization may have been
provided ahead of time through access lists, perhaps specified in a
web page. Authorization may have been provided by means of uploading
some kind of standardized access control list document
6.7. Notifier Generation of NOTIFY requests
The SIP Events specification details the formatting and structure of
NOTIFY messages. However, packages are mandated to provide detailed
information on when to send a NOTIFY, how to compute the state of the
resource, how to generate neutral or fake state information, and
whether state information is complete or partial. This section
describes those details for the "comm-div-info" event package.
A notifier MAY send a NOTIFY at any time. Typically, it will send
one when a communication diversion is enacted on behalf of the user.
The NOTIFY request MAY contain a body containing a comm-div-info
document. The times at which the NOTIFY is sent for a particular
subscriber, and the contents of the body within that notification,
are subject to any rules specified by the authorization policy that
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governs the subscription and to preferences indicated at the time of
subscription.
The body of the NOTIFY MUST be sent using the type "application/
comm-div-info+xml".
Notifiers could detect that a communication diversion was enacted on
behalf of the subscriber via a "History-Info" header field value, per
[2] or [1], sent from an application server hosting the CDIV
application.
6.8. Subscriber Processing of NOTIFY Requests
The SIP Events specification expects event packages to describe the
process followed by the subscriber upon receipt of a NOTIFY request.
In this specification, each NOTIFY request contains a comm-div-info
document
6.9. Handling of Forked Requests
The SIP Events specification requires each package to describe
handling of forked Requests.
This specification only allows a single dialog to be constructed as a
result of emitting an initial SUBSCRIBE request. This guarantees
that only a single notifier is generating notifications for a
particular subscription to a particular user.
6.10. Rate of Notifications
The SIP Events specification requires each package to specify maximum
rate at which notifications can be sent .
Comm-div-info notifiers SHOULD NOT generate notifications for a
single subscription at a rate of more than once every five seconds.
6.11. State Agents
The SIP Events specification requires each package to consider the
role of state agents in the package and, if they are used, to specify
how authentication and authorization are done
This specification does not require state agents to be located in the
network
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6.12. Use of URIs to Retrieve State
The SIP Events specification allows packages to use URIs to retrieve
large state documents.
Comm-div-info documents are fairly small. This event package does
not provide a mechanism to use URIs to retrieve large state
documents.
7. Comm-div-info Document
Comm-div-info document is an XML document [11] that MUST be well-
formed and SHOULD be valid. Communication Diversion Information
documents MUST be based on XML 1.0 and MUST be encoded using UTF-8
[12].
8. Structure of Comm-div-info Format
A Communications Diversion Information document starts with a "comm-
div-info" element. The comm-div-info element has a series of
elements describing the particular communication diversion or the
filter criteria for receiving the communication diversion
information.
8.1. Comm-div-info Element
The comm-div-info element gives information about the specific
communication diversion or it could give information about a
particular selection criteria for the user receiving the
communication diversion information.
8.1.1. comm-div-subs-info Element
The comm-div-subs-info element is used by the subscribing user to
specify the communication diversion information selection criteria
and the communication diversion notification trigger criteria. It
contains the following elements:
8.1.1.1. comm-div-selection-criteria
This element contains information about communication diversion
information selection criteria. It contains following sub-elements
for specifying the selection criteria.
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8.1.1.1.1. originating-user-selection-criteria
This element specifies the originating user information for the
communication i.e the caller. This is specified in the form of
"user-name" and "user-uri". E.g sip:Alice@domain.com. The Username
as well as User-URI specified will be compared with the originating
user information of the current user and if there is a match, then
information about the diversion of this specific communication would
be selected for notification to the Diverting user. It consists of
the following sub-elements.
8.1.1.1.1.1. user-info
This element gives user details like username and URI. This element
has further sub-elements for describing username and user URI
8.1.1.1.1.1.1. User-name
This element gives Username. E.g "Alice".
8.1.1.1.1.1.2. User-URI
This element gives User URI. E.g "sip:Alice@domain.com". It takes
the form of any URI scheme like sip. sips, tel or any other URI
scheme
8.1.1.1.2. diversion-time-selection-criteria
This element specifies the time range for receiving notifications.
It contains following additional elements .
8.1.1.1.2.1. time-range
This element specifies the time range at which notifications for
communication diversions can be sent to the subscriber. This could
be specified in the form of a time-interval to enable periodic
triggering of notifications of communication diversions which took
place in that time-interval.
8.1.1.1.2.1.1. start-time
This element is specifies the start time for receiving notifications.
Its value is expressed in YYYY:MM:DDTHH:MM:SS:Z format.
8.1.1.1.2.1.2. end-time
This element specifies the end time for receiving notifications. Its
value is expressed in YYYY:MM:DDTHH:MM:SS:Z format.
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8.1.1.1.3. diverting-user-selection-criteria
This element gives details of diverting user. The URI specified over
here will be compared with the Request URI of the diverting user for
whom a communication has been diverted. Only if there is a match,
then information about the diversion of this specific communication
would be selected for notification to the Diverting user. This is an
optional parameter. This element consists of sub-elements defined
for "user-info" element Section 8.1.1.1.1.1.1.
8.1.1.1.4. diverted-to-user-selection-criteria
This element gives details of the final target of the communication
i.e the divered-to user. The URI specified in the Request URI of the
new request is compared with the specified diverted-to URI. Only if
there is a match, then information about the diversion of this
specific communication would be selected for notification to the
Diverting user. This element consists of sub-elements defined for
"user-info" element Section 8.1.1.1.1.1.1.
8.1.1.1.5. diversion-reason-selection-criteria
This element contains the reason for communication diversion. It
contains following sub-element:
8.1.1.1.5.1. diversion-reason-info
This element gives the actual reason for the communication diversion.
8.1.1.2. comm-div-ntfy-trigger-criteria
8.1.1.2.1. notification-time-selection-criteria
This element informs the server about the time at which the
notification should be triggered.
8.1.1.2.2. presence-status-selection-criteria
This element gives the presence status of the subscriber, based on
which the decision can be made, whether the subscriber wishes to
receive notification information or not.
8.1.1.2.2.1. presence-selection-info
This element specifies the presence status of the subscriber within
which the subscriber expects to receive notifications about
communication diversions.
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8.1.1.2.3. notification-buffer-interval
8.1.2. Comm-div-ntfy-info Element
This element gives the notification information. This element has
following sub-elements:
8.1.2.1. originating-user-info
Refer to Section 8.1.1.1.1 for details of this element.
8.1.2.2. diverting-user-info
This element gives details of the diverting user.
8.1.2.3. diverted-to-user-info
This element gives details of the final target of the communication
i.e the divered-to user. This element consists of sub-elements
defined for "user-info" element.
8.1.2.4. diversion-time-info
This element gives the time of communication diversion. Its value is
expressed in YYYY:MM:DDTHH:MM:SS format.
8.1.2.5. diversion-reason-info
This element gives the actual reason for the communication diversion.
8.1.3. Comm-div-info-selection-criteria
This element gives the subscriber various to select communication
diversion information. This element has following sub-elements.
8.1.3.1. disable-originating-user-info
This element gives the subscriber option of adding originating user
information to the notification information.
8.1.3.2. disable-diverting-user-info
This element gives the subscriber option of adding diverting-user
information to the notification information.
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8.1.3.3. disable-diverted-to-user-info
This element gives the subscriber option of adding diverting-to-user
information to the notification information.
8.1.3.4. disable-diversion-time-info
This element gives the subscriber option of adding diversion-time
information to the notification information.
8.1.3.5. disable-diversion-reason
This element gives the subscriber option of adding diversion-time
information to the notification information.
8.1.3.6. disable-diversion-rule
This element gives the subscriber option of adding diversion-rule
information to the notification information.
8.2. Sample Notification body
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8.2.1. Instance of communication diversion subscription document
Boss
sip:boss@office.com
1999-05-31T13:20:00-05:00
2006-05-06T13:20:00-05:00
404 302
1999-05-31T13:20:00-05:00
2006-05-06T13:20:00-05:00
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8.2.2. Instance of communication diversion notification document
Boss
sip:boss@office.com
sip:alice@office.com
sip:bob@office.com
1999-06-01T13:20:00-05:00
404
8.3. Schema
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9. Security Considerations
Authentication and authorization of subscriptions have been discussed
in Section 6.6. Lack of authentication or authorization may provide
comm-div-info information to unauthorized parties and can reveal
sensitive information with regards to the user's call receiving
patterns. For example, who calls the user and at what time, etc.
Integrity protection and confidentiality of notifications are also
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Internet-Draft SIP Communication Diversion Notification July 2009
discussed in Section 6.7. If a notifier does not encrypt bodies of
NOTIFY requests, an eavesdropper could learn the status of a SIP user
agent and use it to create malicious sessions. If the notifier does
not integrity protect the bodies of NOTIFY requests, a man-in- the-
middle attacker or malicious SIP proxy could modify the contents of
the comm-div-info event package notification. Although this does not
cause harm, it can create annoyances.
10. IANA Considerations
This document registers the new SIP event package.
10.1. Communication Diversion Information Event Package Registration
This document registers an event package based on the registration
procedures defined in [3]. The following is the information required
for such a registration.
Package Name: Comm-div-info
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).
Person to Contact : Jon Merdith (John.meredith@3gpp.org)
11. Acknowledgements
The authors would like to thank Samir Saklikar for editing the
initial version of the draft and Ban Al-Bakri, Roland Jesske, Jose
Miguel Torres and Paul Kyzivat for their valuable comments and
suggestions.
12. References
12.1. Normative References
[1] 3GPP, "Communication Diversion (CDIV) using IP Multimedia
(IM)Core Network (CN) subsystem; Protocol specification", 3GPP
TS 24.604 8.4.0, June 2009.
[2] 3GPP, "TISPAN; PSTN/ISDN simulation services: Communication
Diversion (CDIV); Protocol specification", 3GPP TS 24.404
7.5.0, June 2009.
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Internet-Draft SIP Communication Diversion Notification July 2009
[3] Mankin, A., Bradner, S., Mahy, R., Willis, D., Ott, J., and B.
Rosen, "Change Process for the Session Initiation Protocol
(SIP)", BCP 67, RFC 3427, December 2002.
[4] Bradner, S., "Key words for use in RFCs to Indicate Requirement
Levels", BCP 14, RFC 2119, March 1997.
[5] Roach, A., "Session Initiation Protocol (SIP)-Specific Event
Notification", RFC 3265, June 2002.
[6] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP:
Session Initiation Protocol", RFC 3261, June 2002.
[7] Moats, R., "URN Syntax", RFC 2141, May 1997.
[8] Moats, R., "A URN Namespace for IETF Documents", RFC 2648,
August 1999.
[9] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
January 2004.
[10] Jennings, C., Audet, F., and J. Elwell, "Session Initiation
Protocol (SIP) URIs for Applications such as Voicemail and
Interactive Voice Response (IVR)", RFC 4458, April 2006.
12.2. Informative References
[11] Maler, E., Sperberg-McQueen, C., Bray, T., and J. Paoli,
"Extensible Markup Language (XML) 1.0 (Second Edition)", World
Wide Web Consortium FirstEdition REC-xml-20001006,
October 2000, .
[12] Schulzrinne, H., Tschofenig, H., Morris, J., Cuellar, J., Polk,
J., and J. Rosenberg, "Common Policy: A Document Format for
Expressing Privacy Preferences", RFC 4745, February 2007.
Appendix A. Change log
[RFC EDITOR NOTE: Please remove this section when publishing]
Changes from draft-avasarala-sipping-comm-div-notification-00
o Changed contact details of co author Subir Saha.
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o Moved from SIPPING to DISPATCH WG.
Changes from draft-avasarala-dispatch-comm-div-notification-00
o Added comm-div-info document structure information and schema for
the event package.
o Added more elaborate description for various sections in comm-div-
info document
Authors' Addresses
Ranjit Avasarala (editor)
Motorola India Pvt Ltd
Bagamane Tech Park, C V Raman Nagar
Bangalore 560093
India
Email: ranjit@motorola.com
John Luc Bakker
Research In Motion Corporation
5000 Riverside Drive, Building 6, Suite 100
Irving, Texas 75039
USA
Email: jbakker@rim.com
Subir Saha
CEO Mobivation
B-602, Salarpuria Silverwood, C V Raman Nagar
Bangalore 560093
India
Email: drsubirsaha@yahoo.com
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