SIPREC Ram Mohan. Ravindranath
Internet-Draft Parthasarathi. Ravindran
Intended status: Standards Track Cisco Systems, Inc.
Expires: January 10, 2012 Paul. Kyzivat
Unaffiliated
July 9, 2011
Session Initiation Protocol (SIP) Recording Metadata
draft-ietf-siprec-metadata-03
Abstract
Session recording is a critical requirement in many communications
environments such as call centers and financial trading. In some of
these environments, all calls must be recorded for regulatory,
compliance, and consumer protection reasons. Recording of a session
is typically performed by sending a copy of a media stream to a
recording device. This document describes the metadata model as
viewed by Session Recording Server(SRS) and the Recording metadata
format.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on January 10, 2012.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
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publication of this document. Please review these documents
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carefully, as they describe your rights and restrictions with respect
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 4
3. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 4
4. Metadata Model . . . . . . . . . . . . . . . . . . . . . . . . 5
5. Recording Metadata Format . . . . . . . . . . . . . . . . . . 6
5.1. XML data format . . . . . . . . . . . . . . . . . . . . . 6
5.1.1. Namespace . . . . . . . . . . . . . . . . . . . . . . 7
5.1.2. recording . . . . . . . . . . . . . . . . . . . . . . 7
6. Recording Metadata elements . . . . . . . . . . . . . . . . . 7
6.1. Recording Session . . . . . . . . . . . . . . . . . . . . 7
6.1.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 8
6.1.2. Associations . . . . . . . . . . . . . . . . . . . . . 8
6.2. Communication Session Group . . . . . . . . . . . . . . . 8
6.2.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 9
6.2.2. Associations . . . . . . . . . . . . . . . . . . . . . 9
6.2.3. XML element . . . . . . . . . . . . . . . . . . . . . 9
6.3. Communication Session . . . . . . . . . . . . . . . . . . 10
6.3.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 10
6.3.2. Associations . . . . . . . . . . . . . . . . . . . . . 11
6.3.3. XML element . . . . . . . . . . . . . . . . . . . . . 12
6.4. Participant . . . . . . . . . . . . . . . . . . . . . . . 12
6.4.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 12
6.4.2. Associations . . . . . . . . . . . . . . . . . . . . . 13
6.4.3. XML element . . . . . . . . . . . . . . . . . . . . . 13
6.5. Media Stream . . . . . . . . . . . . . . . . . . . . . . . 14
6.5.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 14
6.5.2. Associations . . . . . . . . . . . . . . . . . . . . . 15
6.5.3. XML element . . . . . . . . . . . . . . . . . . . . . 15
6.6. Extension Data . . . . . . . . . . . . . . . . . . . . . . 15
6.6.1. Composition . . . . . . . . . . . . . . . . . . . . . 15
6.6.2. XML element . . . . . . . . . . . . . . . . . . . . . 15
6.7. start-time/stop-time . . . . . . . . . . . . . . . . . . . 16
7. SIP Recording Metadata Example . . . . . . . . . . . . . . . . 16
7.1. Complete SIP Recording Metadata Example . . . . . . . . . 16
7.2. Partial Update of Recording metadata XML body . . . . . . 18
8. XML Schema definition for Recording metadata . . . . . . . . . 18
9. Security Considerations . . . . . . . . . . . . . . . . . . . 21
9.1. Connection Security . . . . . . . . . . . . . . . . . . . 21
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 21
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10.1. SIP recording metadata Schema Registration . . . . . . . . 22
11. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 22
12. Appendix A: Metadata Model Object Instances . . . . . . . . . 22
12.1. Use case 1: Basic Call . . . . . . . . . . . . . . . . . . 22
12.2. Use case 2: Basic Call with hold/resume . . . . . . . . . 23
12.3. Use case 3: Basic call with Transfer . . . . . . . . . . . 25
12.4. Conference Use Cases . . . . . . . . . . . . . . . . . . . 26
12.4.1. Case 1: . . . . . . . . . . . . . . . . . . . . . . . 27
12.4.2. Case 2: . . . . . . . . . . . . . . . . . . . . . . . 29
12.4.3. Case 3: . . . . . . . . . . . . . . . . . . . . . . . 31
12.4.4. Case 4: . . . . . . . . . . . . . . . . . . . . . . . 32
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 33
13.1. Normative References . . . . . . . . . . . . . . . . . . . 33
13.2. Informative References . . . . . . . . . . . . . . . . . . 33
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 34
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1. Introduction
Session recording is a critical requirement in many communications
environments such as call centers and financial trading. In some of
these environments, all calls must be recorded for regulatory,
compliance, and consumer protection reasons. Recording of a session
is typically performed by sending a copy of a media stream to a
recording device. This document focuses on the Recording metadata
which describes the communication session. The document describes a
metadata model as viewed by Session Recording Server and the
Recording metadata format, the requirements for which are described
in [I-D.ietf-siprec-req] and the architecture for which is described
in [I-D.ietf-siprec-architecture].
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. This
document only uses these key words when referencing normative
statements in existing RFCs."
3. Definitions
Metadata element: A metadata element represent one block/class of
metadata model.
Metadata attributes: Metadata attributes represents the attributes
listed in each of the blocks of metadata model
Metadata Composition: Composition represents owns/holds relationship
to show Metadata elements contained in another Metadata element
Metadata Associations: Metadata associations represents the
associations between different Metadata elements in the model. It
uses UML notation.
XML element: An XML element represent one XML schema complexType
element (xs:complexType) of XML schema
XML attributes: An XML attribute represent one XML schema element
(xs:element) of XML schema
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4. Metadata Model
Metadata is the information that describes recorded media and the CS
to which they relate. Below diagram shows a model for Metadata as
viewed by Session Recording Server (SRS).
+-------------------------------+ 1
| Recording Session (RS) |---------------+
+-------------------------------+ |
|1..* | 1..* |
| | |
| | 0..* |
| +-----------------+ |
| | Communication | |
| | Session (CS) | 1 |
| | Group |--------------|
| +-----------------+ |
| | 0..1 |
| | |
|0..* | 1..* |
+-------------------------------+ |
| Communication Session (CS) | 1 |
| |---------------|
+-------------------------------+ | +------------+
| 1..* |1..* | | |
| | | 0..* |Extension |
| 2..* |0..* |/\_____| Data |
+-------------+ receives +----------------+ |\/ | |
| Participant |----------| Media Streams | | +------------+
| |0..* 0..*| | |
| | | | |
| | | | |
| | sends | | |
| |----------| | |
| |1.* 0..*| | |
+-------------+ +----------------+ |
| | |
|1 |1 |
| | |
+----------------------------------------+
Session Recording Client (SRC) MAY initiate the Recording Session.
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Here, Recording Session is a completely independent from the
Communication Session that is being recorded at both the SIP dialog
level and at the session level. The metadata MUST be conveyed from
SRC to SRS. The metadata MUST be conveyed within the Recording
Session Dialog.
Note that the metadata model captures changes that occur over the
duration of the recording session. For example, if the call is
transferred from one participant to another, then the SRC MUST convey
a change of participant and the properties of the new media stream to
the SRS.
Some of the metadata is not required to be conveyed explicitly from
the SRC to the SRS, if it can be obtained contextually by the SRS.
For instance, the timing of RS block changes(like Start / Stop time)
may not be explicitly conveyed from the SRC to the SRS (The Date
header in RS dialog SIP message MAY provide the timing, but it is
optional). In such cases the time a change occurred may be assumed
to be the same as the time when notification of the change is
received by the SRS.
5. Recording Metadata Format
This section gives an overview of Recording Metadata Format. The
media related details of metadata MUST be passed across using session
description protocol (SDP) [RFC4566]. SDP attributes describes about
different media formats like audio, video. The other metadata
attributes like participant details MUST be passed across in new
Recording specific XML document namely application/rs-metadata+xml.
The linkage between application/rs-metadata+xml XML schema and
metadata SDP is done using the SDP label attribute (a=label:xxx)
referenced in [RFC4574].
Metadata is passed across in Recording Session(RS) incrementally
whenever there is a change in CS.
5.1. XML data format
Recording Metadata document is an XML document which will be embedded
as a message body. recording element MUST present in all recording
metadata XML document. recording acts as container for all other
elements in this XML document.
Recording object is a XML document. It MUST have the XML declaration
and it SHOULD contain an encoding declaration in the XML declaration,
e.g., "". If the charset
parameter of the MIME content type declaration is present and it is
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different from the encoding declaration, the charset parameter takes
precedence.
Every application conforming to this specification MUST accept the
UTF-8 character encoding to ensure the minimal interoperability.
Syntax and semantics error in recording XML document has to be
informed to the originator using application specific mechanism.
5.1.1. Namespace
The namespace URI for elements defined by this specification is a
Uniform Resource Namespace (URN) [RFC2141], using the namespace
identifier 'ietf' defined by [RFC2648] and extended by [RFC3688].
The URN is as follows: urn:ietf:params:xml:ns:recording
5.1.2. recording
recording element MUST contain an xmlns namespace attribute with
value as urn:ietf:params:xml:ns:siprec. One recording element MUST
present in the all recording metadata XML document.
dataMode element shows whether the XML document is complete document
or partial update. The default value is complete.
6. Recording Metadata elements
This section describes each element of the metadata model, and the
attributes of each element. This section also describes how
different elements are associated and the XML element for each of
them.
6.1. Recording Session
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+-------------------------------+
| Recording Session (RS) |
+-------------------------------+
| | +-----------------+
| Start/End Time | 1 0..* | |
| |/\__________|Extension Data |
| |\/ | |
| | +-----------------+
+-------------------------------+
|1..* | 1..*
| |
|0..* | 0..*
Communication Communication
Session Session Group(CS Group)
A Recording Session element represents a SIP session created between
an SRC and SRS for the purpose of recording a Communication Session.
This element is represented by a SIP RS dialog and hence there is no
need for this element to be reflected in metadata XML.
6.1.1. Attributes
A Recording Session element MAY have attributes like:
o Start/End Time - Start and End time value MUST be derived from
Date header(if present in SIP message) in RS. In cases where Date
header is not present, Start/End time MAY be set to the time at
which SRS receives the notification of SIP message to setup RS /
disconnect RS.
6.1.2. Associations
One instance of Recording Session MUST have:
o Zero or more instances of Communication Session Group. CSG may be
zero because it is optional metadata block. Also the allowance of
zero instances is to accommodate persistent recording, where there
may be none.
o Zero or more instances of Communication Session blocks.
o Each CS Group MUST be associated with one or more Recording
Sessions [Here each RS can be setup by the potentially different
SRCs.]
6.2. Communication Session Group
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Recording Session (RS)
| 1..*
|
| 0..*
+-------------------------------+
| Communication Session |
| Group |
+-------------------------------+
| Unique-ID | +----------------+
| | 1 0..* | |
| |/\_________|Extension Data |
| |\/ | |
+-------------------------------+ +----------------+
| 0..1
|
| 1..*
Communication Session (CS)
A Communication Session Group provides association or linking of
Communication Sessions.
6.2.1. Attributes
A CS Group MUST have a Unique-ID attribute. This Unique-ID is to
group different CSs that are related. SRC (or MAY be SRS) MUST
ensure the uniqueness of Unique-ID in case multiple SRC interacts
with the same SRS. The mechanism by which SRC groups the CS is
outside the scope of SIPREC.
6.2.2. Associations
A communication Session Group MUST be associated with RS and CS in
the following manner:
o There can be one or more Recording Session elements per
Communication Session Group.
o Each Communication Session Group MUST be associated with one or
more RS [Here each RS can be setup by the potentially different
SRCs]
o There MAY be one or more Communication Sessions per CS Group [e.g.
Consult Transfer]
o Each CS MAY be associated to zero or one CS-Group
6.2.3. XML element
Group element is an optional element provides the information about
the communication session group
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Each communication session group (CSG) is represented using one group
element. Each group element has unique URN UUID attribute which
helps to uniquely identify CSG.
6.3. Communication Session
Recording Communication
Session Session Group(CS Group)
|1..* | 0..1
| |
|0..* | 1..*
+-------------------------------+ +-----------------+
| Communication Session (CS) | 1 0..* | |
| |/\_____________|Extension Data |
+-------------------------------+\/ | |
| CS Identifier | +-----------------+
| Termination Reason |
| Start Time |
| End Time |
+-------------------------------+
| |
| 1..* |1..*
| |
| 2..* |0..*
Participant Media Stream
A Communication Session block/element in the metadata model
represents Communication Session and its properties needed as seen by
SRC.
6.3.1. Attributes
A communication Session block MUST have the following attributes:
o Termination Reason - This represents the reason why a CS was
terminated. The communication session MAY contain a Call
Termination Reason. This MAY be derived from SIP Reason header of
CS.
o CS Identifier - This attribute is used to uniquely identify a CS.
o Start Time - This optional attribute represents CS start time
o End Time - This optional attribute represents CS end time
Attributes like Retention (represent the value/duration for which
Media streams of the CS needs to be retained), Force Deletion, Access
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Information e.t.c that are primarily related to policy will not be
passed in metadata from SRC to SRS. However if there are
implementations where SRC has enough information, this could be sent
as Extension Data attached to CS
6.3.2. Associations
A Communication Session MUST be associated to CS-Group, Participant,
Media Stream and Recording Session blocks. Cardinalities between CS
and Participant allows:
o CS to have atleast two or more participants
o Participant MUST be associated with one or more CS's. This may
even includes participants who are not directly part of any CS.
An example of such a case is participants in a premixed media
stream. The SRC may have knowledge of such Participants, yet not
have any signaling relationship with them. This might arise if
one participant in CS is a conf focus. Another use case is if one
UA in CS works in 3pcc mode to acquire an MoH media stream, this
might be reflected as unique source for media stream without
having a reported signaling relationship to it. In all these
cases if SRC can learn enough information about the Participant,
they MUST be associated with CS.
o The model also allows participants in CS that are not participants
in the media. An example is the identity of a 3pcc controller
that has initiated a CS to two or more participants of the CS.
Another example is the identity of a conference focus. Of course
a focus is probably in the media, but since it may only be there
as a mixer, it may not report itself as a participant in any of
the media streams.
Cardinalities between CS and Media Stream allows:
o A CS to have zero or more Streams
o A stream can be associated with 1 or more CS. An example is
multicast MoH stream which might be associated with many CSs.
Also if we were to consider a B2BUA to have a separate CS on each
"side" then they might share a stream.(Though more likely this
would be treated as a single CS.)
Cardinalities between CS and RS allows:
o One instance of RS MUST have Zero or more instances of
Communication Session blocks.
o Each CS MUST be associated with one more RS [ Here each RS can be
potentially setup by different SRCs]
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6.3.3. XML element
Session element provides the information about the communication
session
Each communication session(CS) has one session element. Each session
element has unique URN UUID attribute which helps to uniquely
identify CS.
Reason element MAY be included to indicate the reason for
termination. group-ref element MAY exist to indicate the group where
the mentioned session belongs.
6.4. Participant
Communication Session (CS)
| 1..*
|
| 2..*
+-------------------------------+
| Participant |
| |
+-------------------------------+
| AoR list | +-----------------+
| Name | 1 0..* | |
| Participant Type |/\__________|Extension Data |
| |\/ | |
+-------------------------------+ +-----------------+
| 0..* 1..*|
receives| |sends
| 0..* 0..*|
Media Stream
A Participant block has information about a device that is part of a
CS and/or contributes/consumes media stream(s) belonging to a CS.
6.4.1. Attributes
Participant has attributes like:
o AoR list - Has list of AoRs. An AoR MAY be SIP/SIPS/TEL URI.
There MAY be cases where a participant can have more than one AoR
[ e.g. P-Asserted-ID which can have both SIP and TEL URIs]
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o Name - This attribute represents Participant name(SIP display
name) or DN number ( in case it is known)
Other attributes [ like Participant Role, Participant type ] MAY be
carried as part of extension data to Participant from SRC to SRS.
6.4.2. Associations
Cardinalities between participant and Media Stream allows:
o Participant to receives zero or more media streams
o Participant to send zero or more media streams. (Same participant
provides multiple streams e.g. audio and video)
o Media stream to be received by zero or more participants. Its
possible, though perhaps unlikely, that a stream is generated but
sent only to the SRC and SRS, not to any participant. E.g. In
conferencing where all participants are on hold and the SRC is
collocated with the focus. Also a media stream may be received by
multiple participants (e.g. Whisper calls, side conversations).
o Media stream to be sent by one or more participants (pre-mixed
streams).
Example of a case where a participant may receive Zero or more
streams - a Supervisor may have side conversation with Agent, while
Agent converses with customer.
6.4.3. XML element
Participant element provides information regarding the specific
participant involved in the recording
There MUST be atleast 2 participant for any given session. "send" or
"receive" element in each participant is associating SDP m-lines with
the participant. send element indicates that participant is sending
the stream of media with the mentioned media description. recv
element indicates that participant is receiving the stream and by
default all participant will receive the stream. recv element has
relevance in case whisper call scenario wherein few of the
participant in the session receives the stream and not others.
Participant MUST have AOR element which contains SIP/SIPS URI to
identify the participant. AOR element is SIP/SIPS URI FQDN or IP
address which represents the user. name is an optional element to
represent display name.
Each participant element has unique URN UUID attribute which helps to
uniquely identify participant and session URN UUID to associate
participant with specific session element. URN UUID of participant
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*MUST* used in the scope of CSG and no new URN UUID has to be created
for the same element (participant, stream) between different CS in
the same CSG. In case URN UUID has to be used permanent, careful
usage of URN UUID to original AoR has to be decided by the
implementers and it is implementer's choice.
6.5. Media Stream
Participant
| 0..* 1..*|
receives| |sends
| 0..* 0..*|
+-------------------------+
| Media Stream |
| |
Communication 1..* 0..* +-------------------------+
Session ------------| Start Time | +----------+
| End Time |1 0..* | |
| Media Stream Reference |/\______|Extension |
| Content |\/ | Data |
+-------------------------+ +----------+
A Media Stream block MUST have properties of media as seen by SRC and
sent to SRS. Different instances of Media Stream block would be
created whenever there is a change in media (e.g. dir change like
pause/resume and/or codec change and/or participant change.).
6.5.1. Attributes
A Media Stream block MUST have the following attributes:
o Start Time - Represents Media Start time at SRC.
o End Time - Represents Media End time at SRC. This is an optional
attribute and MAY be included after a stream ends
o Media Stream Reference - In implementations this can reference to
m-line
o Content - The content of an MS element will be described in terms
of value from the RFC 4796 [RFC4796] registry.
NOTE: how the content attribute is conveyed (in metadata XML or in RS
SDP) is still open.
The metadata model should include media streams that are not being
delivered to the SRS. Examples include cases where SRC offered
certain media types but SRS chooses to accept only a subset of them
OR an SRC may not even offer a certain media type due it its
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restrictions to record
6.5.2. Associations
A Media Stream MUST be associated with Participant and CS. The
details of association with the Participant are described in the
Participant block section. The details of association with CS is
mentioned in the CS section.
6.5.3. XML element
Stream element indicates SDP media lines associated with the session
and participants.
This element indicates the SDP m-line properties like label
attributes, media mode. Label attribute is used to link m-line SDP
body using label attribute in SDP m-line. The media mode helps in
understanding whether the media is mixed or not.
Each stream element has unique URN UUID attribute which helps to
uniquely identify stream and session URN UUID to associate stream
with specific session element. The open item here is whether to use
URN UUID (global id) or xml:id (local id).
6.6. Extension Data
A recording metadata object contains additional data not specified as
part of siprec. This is intended to accommodate future standards
track extensions, as well as vendor and user specific extensions.
The mechanism MUST provide a means of unambiguously distinguishing
such extension data.
6.6.1. Composition
Extension data element MUST be contained/owned by a Metadata element.
Each instance of Metadata element(except extension data element
itself) MAY have
o Zero or more instances of Extension data element
o Each Extension data element MUST be contained/owned by an Metadata
element other than itself
6.6.2. XML element
Extensiondata element provides the mechanism by which namespace/
element MAY be extended with standard or proprietary information.
extensiondata element MUST include any other XML namespace. Multiple
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namespace MAY exists under extensiondata. extensiondata element exist
in each level like recording, session, participant, stream to provide
extensiondata specific to each element. extensiondata element MUST be
part of parent element for which the additional information is sent
and hence no Unique ID is needed.
6.7. start-time/stop-time
start-time/stop-time contains a string indicating the date and time
of the status change of this tuple. The value of this element MUST
follow the IMPP datetime format [RFC3339]. Timestamps that contain
'T' or 'Z' MUST use the capitalized forms. At a time, any of the
time tuple start-time or stop-time MAY exist in the element namely
group, session, participant, stream and not both timestamp at the
same time.
As a security measure, the timestamp element SHOULD be included in
all tuples unless the exact time of the status change cannot be
determined.
NOTE: Open item on whether start/stop attribute is needed for all
Metadata elements
7. SIP Recording Metadata Example
7.1. Complete SIP Recording Metadata Example
The following example provides all the tuples involved in Recording
Metadata XML body.
2010-12-16T23:41:07Zsip:alice@cisco.comFOO!barurn:uuid:efe3930b-2a31-4e6a-a6ab-203fd7078302
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2010-12-16T23:41:07ZFOO!barsip:partha@blr.cisco.comurn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0burn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b172010-12-16T23:41:07ZFOO!barsip:paul@box.cisco.comurn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b17urn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0b2010-12-16T23:41:07ZFOO!bar2010-12-16T23:41:07Z2010-12-16T23:41:07Z2010-12-16T23:41:07Z2010-12-16T23:41:07Z
SIP Recording Metadata Example XML body
7.2. Partial Update of Recording metadata XML body
The following example provides partial update in Recording Metadata
XML body for the above example. The example illustrate the stop time
of the specific stream.
partial
Partial update of SIP Recording Example XML body
8. XML Schema definition for Recording metadata
This section defines XML schema for Recording metadata document
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9. Security Considerations
The metadata information sent from SRC to SRS MAY reveal sensitive
information about different participants in a session. For this
reason, it is RECOMMENDED that a SRC use a strong means for
authentication and metadata information protection and that it apply
comprehensive authorization rules when using the metadata format
defined in this document. The following sections will discuss each
of these aspects in more detail.
9.1. Connection Security
It is RECOMMENDED that a SRC authenticate SRS using the normal SIP
authentication mechanisms, such as Digest as defined in Section 22 of
[RFC3261]. The mechanism used for conveying the metadata information
MUST ensure integrity and SHOULD ensure confidentially of the
information. In order to achieve these, an end-to-end SIP encryption
mechanism, such as S/MIME described in [RFC3261], SHOULD be used.
If a strong end-to-end security means (such as above) is not
available, it is RECOMMENDED that a SRC use mutual hop-by-hop
Transport Layer Security (TLS) authentication and encryption
mechanisms described in "SIPS URI Scheme" and "Interdomain Requests"
of [RFC3261].
10. IANA Considerations
This specification registers a new XML namespace, and a new XML
schema.
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10.1. SIP recording metadata Schema Registration
URI: urn:ietf:params:xml:ns:recording
Registrant Contact: IETF SIPREC working group, Ram mohan
R(rmohanr@cisco.com)
XML: the XML schema to be registered is contained in Section 6.
Its first line is and its last
line is
11. Acknowledgement
We wish to thank John Elwell(Siemens-Enterprise), Henry Lum(Alcatel-
Lucent), Leon Portman(Nice), De Villers, Andrew Hutton(Siemens-
Enterprise), Deepanshu Gautam(Huawei), Charles Eckel(Cisco), Muthu
Arul(Cisco), Michael Benenson(Cisco), Hadriel Kaplan (ACME), Brian
Rosen(Neustar), Scott Orton(Broadsoft) for their valuable comments
and inputs.
We wish to thank Joe Hildebrand(Cisco), Peter Saint-Andre(Cisco) for
the valuable XML related guidance.
12. Appendix A: Metadata Model Object Instances
This section describes the metadata model object instances for
different use cases of SIPREC. For the sake of simplicity as the
media streams sent by each of the participants is received by every
other participant in these use cases, it is NOT shown in the object
instance diagrams below. Also for the sake of ease not all
attributes of each block are shown in these instance diagrams.
12.1. Use case 1: Basic Call
Basic call between two Participants A and B. In this use case each
participant sends one Media Stream. For the sake of simplicity
"receives" lines are not shown in this instance diagram. Media
Streams sent by each participant is received all other participants
of that CS.
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+-------------------------------+
| Recording Session (RS) |
+-------------------------------+
|
|
|
+----------------+
| Communication |
| Session (CS) |
+----------------+-----------------------+
| Start Time | |
+----------------+ |
| |
|-------------------+ |
| | |
+---------------+ +---------------+ |
| ParticipantA | | ParticipantB | |
| | | | |
+---------------+ +---------------+ |
| | |
sends | | sends |
| | |
+---------------+ +---------------+ |
|Media Stream A1| |Media Stream B1| |
+---------------+ +---------------+ |
|MediaStream Ref| |MediaStream Ref| |
|Start Time | |Start Time | |
+---------------+ +---------------+ |
| | |
+-----------------------------------+
12.2. Use case 2: Basic Call with hold/resume
Basic call between two Participants A and B and with Participant A or
B doing a Hold/Resume. In this use case each participant sends one
Media Stream. After Hold/Resume the properties of Media can change.
For the sake of simplicity "receives" lines are not shown in this
instance diagram. Media Streams sent by each participant is received
all other participants of that CS.
+-------------------------------+
| Recording Session (RS) |
+-------------------------------+
| |
| |
| |
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| +-------------------------------+
| | Communication Session (CS) |
| +-----------| Group(CSG) |
| | +-------------------------------+
| | | Unique-id1 |
| | +-------------------------------+
| |
| |
| |
+----------------+
| Communication |
+-| Session (CS) |----------------------------------------------+
| +----------------+ |
| | | |
| +----------------+ |
| | |
| |-------------------+ |
| | | |
| +---------------+ +---------------+ |
| | ParticipantA | | ParticipantB |-----------+ |
| | |--+ | | | |
| +---------------+ | +---------------+ |sends(After |
| | | | | | | Resume) |
| | | | | | +--------------+ |
| sends | | +--+ | sends | |MediaStream B3| |
| | -----+ | | +-----+ +--------------+ |
| +---------------+ | | +---------------+ | |MediaStreamRef|-|
| |Media Stream A1| | | |Media Stream B1| | | Start Time | |
| +---------------+ | | +---------------+ | | | |
+-|MediaStreamref | | | |MediaStreamRef | | +--------------+ |
|Start Time | | | |Start Time |-|-------------------|
+---------------+ | | +---------------+ | |
| | | |
+------------+ |sends |sends (hold) |
| sends |(Resume) | |
| (hold) +-------+ +-------+ |
| | | |
+---------------+ +---------------+ +--------------+ |
|Media Stream A2| |Media Stream A3| |MediaStream B2| |
+---------------+ +---------------+ | | |
|MediaStreamref | |MediaStreamRef | +--------------+ |
|End Time | |Start Time | |Codec Params | |
+---------------+ +---------------+ |end Time | |
| | | | |
| | +--------------+ |
| | | |
+------------------------------------------------------+
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12.3. Use case 3: Basic call with Transfer
Basic call between two Participants A and B and with Participant A
transfer(consult transfer) to Participant C. In this use case each
participant sends one Media Stream. After transfer the properties of
Participant A Media can change. For the sake of simplicity
"receives" lines are not shown in this instance diagram. Media
Streams sent by each participant is received all other participants
of that CS.
+-------------------------------+
| Recording Session (RS) |-------+
+-------------------------------+ |
| |
| |
| |
+-------------------------------+ |
| Communication Session (CS) | |
| Group(CSG) | |
+-------------------------------+ |
| Unique-id1 | |
+-------------------------------+ |
| |
|----------------------------+
|
|-----------------+
| |
+----------------+ +----------------+
| Communication | | Communication |
| Session (CS)1 | | Session (CS)2 |
+----------------+ +----------------+-----------+
| | | | |
+----------------+ +----------------+ |
| |
|-------------------+ |
| | | |
+---------------+ | +---------------+ |
| ParticipantA | | | ParticipantB | |
| | | | | |
+---------------+ | +---------------+ |
| | | |
sends | | | sends |
| | | |
+---------------+ | +---------------+ |
|Media Stream A1| | |Media Stream B1| |
+---------------+ | +---------------+ |
| | | | | |
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| | | | Media Stream | |
| Media Stream |---+---| Ref | |
| Ref | | | |
+---------------+ +---------------+ |
|
|
+----------------------------|
| |
+--------------------------------+ |
| | |
+---------------+ +---------------+ |
| Participant A | | Participant C | |
| (same) | | | |
+---------------+ +---------------+ |
| | |
| sends (After transfer) | sends |
+----------------+ +----------------+|
| Media Stream A2| | Media Stream C1||
+----------------+ +----------------+|
| Media StreamRef| | Media StreamRef||
| | | ||
| | | ||
+----------------+ +----------------+|
| | |
| | |
| | |
+-------------------------------------------+
12.4. Conference Use Cases
Depending on who act as SRC and the information that an SRC has there
can be several ways to model conference use cases. This section has
instance diagrams for the following cases:
o A CS where one of the participant (which is also SRC) is a user in
a conference
o A CS where one of the participant is focus ( which is also SRC)
o A CS where one of the participant is user and the SRC is a
different entity like B2BUA
o A CS where one of the participant is focus and the SRC is a
different entity like B2BUA
NOTE: There MAY be other ways to model the same use cases depending
on what information the SRC has.
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12.4.1. Case 1:
This is the usecase where there is a CS with one of the participant
(who is also SRC) as a user in a conference. For the sake of
simplicity the receive lines for each of the participant is not
shown.
+---------------------------------------------------+
| Communication Session |
| +-------------+ +--------------+ |
| | | | | |
| |Participant B| | Participant A| |
| | (User in |--------------| | |
| | conf/SRC) | | | |
| +-------------+ +--------------+ |
| | | | | |
+---------------------------------------------------+
| | | |
| | | |
D E F G (Participants of Conference)
Instance Diagram:
+-------------------------------+
| Recording Session (RS) |--+
+-------------------------------+ |
| |
| |
| |
+-------------------------------+ |
| Communication Session (CS) | |
| Group(CSG) | |
+-------------------------------+ |
| Unique-id1 | |
+-------------------------------+ |
| |
|-----------------------+
|
+----------------+
| Communication |
| Session (CS) |--+----------------+-----+
+----------------+ | | |
| | | | |
+----------------+ | | |
| | | |
| | | |
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| | | |
+---------------+ | | |
| ParticipantA | | | |
| | | | |
+---------------+ | | |
| | | |
sends | | | |
| | | |
+---------------+ | | |
|Media Stream A1| | | |
+---------------+ | | |
|MediaStream Ref|-----|----------------+ |
| | | | |
+---------------+ | | |
| | |
| | |
+-------------+ | |
| | |
| | |
+----------------+ | |
| Participant B | | |
| (in conf) | | |
+----------------+ | |
| | |
sends | | |
| | |
+----------------+ | |
| Media Stream B1|---------------------+ |
+----------------+ sends |
| MediaStream Ref| |
| | +-----------------+
+----------------+ |
| |
|sends |
| |
+-----------------+-------------+------------+
| | | |
| | | |
+------------+ +------------+ +------------+ +-------------+
|participantD| |ParticipantE| |ParticipantF| |Participant G|
+------------+ +------------+ +------------+ +-------------+
In this example we have two participants A and B who are part of a
Communication Session(CS). One of the participants B is part of a
conference and also acts as SRC.There can be two cases here. B can
be a participant of the conference or B can be a focus. In this
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instance diagram Participant B is a user in a conference. The SRC
(Participant B) subscribes to conference event package to get the
details of other particiants. Participant B(SRC) sends the same
through the metadata to SRS. In this instance diagram the Media
Stream(mixed stream) sent from Participant B has media streams
contributed by conference participants (D,E,F and G). For the sake
of simplicity the "receives" line is not shown here. In this example
the media stream sent by each participant(A or B) of CS is received
by all other participant(A or B).
12.4.2. Case 2:
This is the usecase where there is a CS where one of the participant
is focus ( which is also SRC).
+---------------------------------------------------+
| Communication Session |
| +--------------+ +--------------+ |
| | |--------------| | |
| |Participant C | | Participant A| |
| | (Focus in |------+ | | |
| | conf and SRC)|---+ | +--------------+ |
| +--------------+ | | |
| | | +---------+ |
| | | | |
| +--------------+ | +---------------+ |
| | Participant B| +---+ | Participant D | |
| | | | | | |
| +--------------+ | +---------------+ |
| | |
| +--------------+ |
| |Participant E | |
| | | |
| +--------------+ |
| |
+---------------------------------------------------+
Instance Diagram:
+-------------------------------+
| Recording Session (RS) |
+-------------------------------+
|-------------------------+
| |
| |
+-------------------------------+ |
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| Communication Session (CS) | |
| Group(CSG) | |
+-------------------------------+ |
| Unique-id1 | |
+-------------------------------+ |
| |
|-------------------------+
|
+----------------+
| Communication |
| Session (CS) |----------------------+
+----------------+ |
| | |
+----------------+ |
| |
|-------------------+ |
| | | |
+---------------+ | +---------------+ |
| ParticipantA | | | ParticipantB | |
| | | | | |
+---------------+ | +---------------+ |
| | | |
sends | | | sends |
| | | |
+---------------+ | +---------------+ |
|Media Stream A1| | |Media Stream B1| |
+---------------+ | +---------------+ |
|MediaStream Ref| | |MediaStream Ref| |
| |---+---| | |
+---------------+ +---------------+ |
|
+----------------------------------+
| | | |
| | | |
+---------------+ | +---------------+ |
| ParticipantD | | | ParticipantE | |
| | | | | |
+---------------+ | +---------------+ |
| | | |
sends | | | sends |
| | | |
+---------------+ | +---------------+ |
|Media Stream D1| | |Media Stream E1| |
+---------------+ | +---------------+ |
|MediaStream Ref| | |MediaStream Ref| |
| |---+---| | |
+---------------+ +---------------+ |
|
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|
+----------+
+-----------------|
| |
| |
+----------------+ |
| Participant C | |
| (focus +src) | |
+----------------+ |
| |
Sends | +-------+
| |
"sends" OR | |
contributed +----------------+
by | Media Stream C1|
Participants+----------------+ "receives" by participants A,B,D,E
A,B,D,E | MediaStream Ref|------------------------------------
------------| Codec Params |
+----------------+
In this example we have two participants A and B who are part of a
Communication Session(CS). One of the participants (C) is focus of a
conference and also acts as SRC. The SRC (Participant C) being the
Focus of the conference has access to the details of other
particiants. SRC (Participant C) sends the same through the metadata
to SRS. In this instance diagram the Media Stream(mixed stream) sent
by C has media streams contributed by conference participants (A, B,
D and E). Participants A, B,D and E sends Media Streams A1, B1, D1
and E1 respectively. The media stream sent by Participant C(Focus)
is received by all other participants of CS. For the sake of
simplicity the "receives" line is not shown linked to all other
participants.
NOTE: SRC ( Participant C) can send mixed stream or seperate streams
to SRS
12.4.3. Case 3:
A CS where one of the participant is user and the SRC is a different
entity like B2BUA. In this case the SRC may not know that one of the
user is part of conference. Hence the instance diagram will not have
information about the conference participants.
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+---------------------------------------------------+
| Communication Session |
| +-------------+ +------+ +--------------+ |
| | | | (SRC)| | | |
| |Participant B|--|B2BUA |----| Participant A| |
| | (User in | +------+ | | |
| | conf) | | | |
| +-------------+ +--------------+ |
| | | | | |
+---------------------------------------------------+
| | | |
| | | |
D E F G (Participants of Conference)
12.4.4. Case 4:
A CS where one of the participant is focus and the SRC is a different
entity like B2BUA. In this case the participant which is focus sends
"isfocus" in SIP message to SRC. The SRC subscribe to conference
event package on seeing this "isfocus". SRC learns the details of
other participants of conference from the conference package and send
the same in metadata to SRS. The instance diagram for this use case
is same as Case 1.
+--------------------------------+
| Conference Event Package |
| |
+--------------------------------+
|
| subscribes
|
+---------------------|-----------------------------+
| Communication |Session |
| +-------------+ +------+ +--------------+ |
| | | | (SRC)| | | |
| |Participant B|--|B2BUA |----| Participant A| |
| | (FOCUS in | +------+ | | |
| | conf) | | | |
| +-------------+ +--------------+ |
| | | | | |
+---------------------------------------------------+
| | | |
| | | |
D E F G (Participants of Conference)
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13. References
13.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2141] Moats, R., "URN Syntax", RFC 2141, May 1997.
[RFC3261] 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.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
January 2004.
[RFC3339] Klyne, G., Ed. and C. Newman, "Date and Time on the
Internet: Timestamps", RFC 3339, July 2002.
[RFC4566] Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
Description Protocol", RFC 4566, July 2006.
[RFC4574] Levin, O. and G. Camarillo, "The Session Description
Protocol (SDP) Label Attribute", RFC 4574, August 2006.
[RFC4796] Hautakorpi, J. and G. Camarillo, "The Session Description
Protocol (SDP) Content Attribute", RFC 4796,
February 2007.
13.2. Informative References
[I-D.ietf-siprec-req]
Rehor, K., Portman, L., Hutton, A., and R. Jain, "Use
Cases and Requirements for SIP-based Media Recording
(SIPREC)", draft-ietf-siprec-req-12 (work in progress),
June 2011.
[I-D.ietf-siprec-architecture]
Hutton, A., Portman, L., Jain, R., and K. Rehor, "An
Architecture for Media Recording using the Session
Initiation Protocol", draft-ietf-siprec-architecture-02
(work in progress), April 2011.
[RFC2648] Moats, R., "A URN Namespace for IETF Documents", RFC 2648,
August 1999.
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Authors' Addresses
Ram Mohan Ravindranath
Cisco Systems, Inc.
Cessna Business Park,
Kadabeesanahalli Village, Varthur Hobli,
Sarjapur-Marathahalli Outer Ring Road
Bangalore, Karnataka 560103
India
Email: rmohanr@cisco.com
Parthasarathi Ravindran
Cisco Systems, Inc.
Cessna Business Park,
Kadabeesanahalli Village, Varthur Hobli,
Sarjapur-Marathahalli Outer Ring Road
Bangalore, Karnataka 560103
India
Email: partr@cisco.com
Paul Kyzivat
Unaffiliated
Boxborough, MA
USA
Email: pkyzivat@alum.mit.edu
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