SIPREC Ram Mohan. Ravindranath
Internet-Draft Cisco Systems, Inc.
Intended status: Standards Track Parthasarathi. Ravindran
Expires: March 4, 2012 Sonus Networks
Paul. Kyzivat
Unaffiliated
September 1, 2011
Session Initiation Protocol (SIP) Recording Metadata
draft-ietf-siprec-metadata-04
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-
Drafts is at http://datatracker.ietf.org/drafts/current/.
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 March 4, 2012.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
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publication of this document. Please review these documents
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 . . . . . . . . . . . . . . . . . . 7
5.1. XML data format . . . . . . . . . . . . . . . . . . . . . 7
5.1.1. Namespace . . . . . . . . . . . . . . . . . . . . . . 8
5.1.2. recording . . . . . . . . . . . . . . . . . . . . . . 8
6. Recording Metadata classes . . . . . . . . . . . . . . . . . . 8
6.1. Recording Session . . . . . . . . . . . . . . . . . . . . 8
6.1.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 9
6.1.2. Linkages . . . . . . . . . . . . . . . . . . . . . . . 9
6.1.3. XML element . . . . . . . . . . . . . . . . . . . . . 9
6.2. Communication Session Group . . . . . . . . . . . . . . . 10
6.2.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 10
6.2.2. Linkages . . . . . . . . . . . . . . . . . . . . . . . 10
6.2.3. XML element . . . . . . . . . . . . . . . . . . . . . 11
6.3. Communication Session . . . . . . . . . . . . . . . . . . 11
6.3.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 12
6.3.2. Linkages . . . . . . . . . . . . . . . . . . . . . . . 12
6.3.3. XML element . . . . . . . . . . . . . . . . . . . . . 13
6.4. Participant . . . . . . . . . . . . . . . . . . . . . . . 13
6.4.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 14
6.4.2. Linkages . . . . . . . . . . . . . . . . . . . . . . . 14
6.4.3. XML element . . . . . . . . . . . . . . . . . . . . . 15
6.5. Media Stream . . . . . . . . . . . . . . . . . . . . . . . 15
6.5.1. Attributes . . . . . . . . . . . . . . . . . . . . . . 16
6.5.2. Linkages . . . . . . . . . . . . . . . . . . . . . . . 17
6.5.3. XML element . . . . . . . . . . . . . . . . . . . . . 17
6.6. Extension Data . . . . . . . . . . . . . . . . . . . . . . 17
6.6.1. Linkages . . . . . . . . . . . . . . . . . . . . . . . 17
6.6.2. XML element . . . . . . . . . . . . . . . . . . . . . 17
6.7. associate-time/disassociate-time . . . . . . . . . . . . . 18
6.8. Unique ID format . . . . . . . . . . . . . . . . . . . . . 18
7. SIP Recording Metadata Example . . . . . . . . . . . . . . . . 18
7.1. Complete SIP Recording Metadata Example . . . . . . . . . 18
7.2. Partial Update of Recording metadata XML body . . . . . . 20
8. XML Schema definition for Recording metadata . . . . . . . . . 20
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9. Security Considerations . . . . . . . . . . . . . . . . . . . 23
9.1. Connection Security . . . . . . . . . . . . . . . . . . . 23
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24
10.1. SIP recording metadata Schema Registration . . . . . . . . 24
11. Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . 24
12. Appendix A: Metadata Model Object Instances . . . . . . . . . 24
12.1. Use case 1: Basic Call . . . . . . . . . . . . . . . . . . 24
12.2. Use case 2: Hold/Resume . . . . . . . . . . . . . . . . . 25
12.3. Use case 3: Basic call with Transfer . . . . . . . . . . . 27
12.4. Conference Use Cases . . . . . . . . . . . . . . . . . . . 28
12.4.1. Case 1: . . . . . . . . . . . . . . . . . . . . . . . 29
12.4.2. Case 2: . . . . . . . . . . . . . . . . . . . . . . . 31
12.4.3. Case 3: . . . . . . . . . . . . . . . . . . . . . . . 33
12.4.4. Case 4: . . . . . . . . . . . . . . . . . . . . . . . 34
13. Appendix B: Metadata XML schema Instances . . . . . . . . . . 35
13.1. Use case 1: Basic Call . . . . . . . . . . . . . . . . . . 35
13.2. Use case 2: Hold/resume . . . . . . . . . . . . . . . . . 37
13.3. Use case 3: Basic Call with transfer . . . . . . . . . . . 39
14. References . . . . . . . . . . . . . . . . . . . . . . . . . . 43
14.1. Normative References . . . . . . . . . . . . . . . . . . . 43
14.2. Informative References . . . . . . . . . . . . . . . . . . 44
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 44
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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 [RFC6341] 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 Model: The Metadata model is a class diagram in Unified
Modelling Language(UML). The model is a structure diagram that
describes the structure of a recording's Metadata by showing the
classes, their attributes, and the relationships among the classes.
Each block in the model above represents a class. The linkages
between the classes represents the relationships between the classes.
Object diagrams represents instance diagrams of the class diagram and
conveys snapshot of metadata.
Metadata classes: Each block in the model represents a class. In the
metadata model each class is represented as a block having the block
name. The description of each class also has representation of its
attributes in a second compartment below the class name. Each
instance of a class(namely the object) contributes some information
to the recording's Metadata.
Attributes: Attributes represents the attributes listed in each of
the classes. The attributes of a class are listed in the second
compartment below the class name. Each instance of class conveys
values for these attributes which adds to the recording's Metadata.
Linkages: Linkages represents the relationship between the classes in
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the model. It represents the logical connections betweens classes(or
objects) in class diagrams/ object diagrams. The linkages can be
associations or composition in the Metadata model of this document.
An association represents a family of links. Binary associations
(with two ends) are normally represented as a line, with each end
connected to a class/object box. An association can be named, and
the ends of an association can be adorned with role names, ownership
indicators, multiplicity, visibility, and other properties. For
instance, in the metadata model we have "sends" association between
participant and media stream classes.The relation composition
represents owns/holds relationship to show classes contained in
another class. For instance, extension data class is contained in
one of the other class(like stream or participant or any of the other
in the model).The UML graphical representation of a composition
relationship is a filled diamond shape on the containing class end of
the tree of lines that connect contained class(es) to the containing
class.
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
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).
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+-------------------------------+ 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 |
| | |
+----------------------------------------+
The Metadata model is a class diagram in Unified Modelling
Language(UML). The model is a structure diagram that describes the
structure of a recording's Metadata by showing the classes, their
attributes, and the relationships among the classes. Each block in
the model above represents a class. The linkages between the classes
represents the relationships which can be associations or
Composition. Session Recording Client (SRC) MAY initiate the
Recording Session. 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
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MUST be conveyed from SRC to SRS.
The model allows the capture of a snapshot of a recording's Metadata
at a given instant in time. Metadata changes to reflect changes in
what is being recorded. For example, if the call is transferred from
one participant to another, then the SRC conveys the changes in the
model ( In this instance 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 object changes(like Start / Stop time)
may not be explicitly conveyed from the SRC to the SRS (The Date
header in RS dialog SIP message provides 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. This is not true in cases where SRS requests a
snapshot of metadata from SRC.
5. Recording Metadata Format
This section gives an overview of Recording Metadata Format. Some
data from the metadata model is assumed to be made available to the
SRS through Session Description Protocol (SDP)[RFC4566], and
therefore this data is not represented in the XML document format
specified in this document. SDP attributes describes about different
media formats like audio, video. The other metadata attributes like
participant details are represented in a new Recording specific XML
document namely application/rs-metadata+xml. The SDP label attribute
[RFC4574] provides an identifier by which a metadata XML document can
refer to a specific media description in the SDP sent from the SRC to
the SRS.
The XML document format can be used to represent either the complete
metadata or a partial update to the metadata. The latter includes
only elements that have changed compared to the previously reported
metadata.
5.1. XML data format
Recording Metadata document is an XML document. 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., "<?xml version='1.0' encoding='UTF-8'?>". If the charset
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parameter of the MIME content type declaration is present and it is
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:recording. 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 classes
This section describes each class of the metadata model, and the
attributes of each class. This section also describes how different
classes are linked 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)
Each instance of a Recording Session class (namely the Recording
Session Object) represents a SIP session created between an SRC and
SRS for the purpose of recording a Communication Session.
6.1.1. Attributes
A Recording Session class has the following attributes:
o Start/End Time - Represents the Start/End time of a Recording
Session object.
6.1.2. Linkages
Each instance of Recording Session has:
o Zero or more instances of Communication Session Group. CSG may be
zero because it is optional metadata object. Also the allowance
of zero instances is to accommodate persistent recording, where
there may be none.
o Zero or more instances of Communication Session objects.
6.1.3. XML element
Recording Session object is represented by recording XML element.
That in turn relies on the SIP/SDP session with which the XML
document is associated to provide some of the attributes of the
Recording Session element.
Start and End time value are derivable from Date header(if present in
SIP message) in RS. In cases where Date header is not present,
Start/End time are derivable from the time at which SRS receives the
notification of SIP message to setup RS / disconnect RS.
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6.2. Communication Session Group
Recording Session (RS)
| 1..*
|
| 0..*
+-------------------------------+
| Communication Session |
| Group |
+-------------------------------+
| Unique-ID | +----------------+
| associate-time | 1 0..* | |
| disassociate-time |/\_________|Extension Data |
| |\/ | |
+-------------------------------+ +----------------+
| 0..1
|
| 1..*
Communication Session (CS)
One instance of a Communication Session Group class (namely the
Communication Session Group object) provides association or linking
of Communication Sessions.
6.2.1. Attributes
A CS Group has the following attributes:
o Unique-ID - This Unique-ID is to group different CSs that are
related. SRC (or SRS) is responsible for ensuring 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.
o Associate-time - Associate-time for CS-Group shall be calculated
by SRC as the time when a grouping is formed. The rules that
determine how a grouping of different Communication Session
objects is done by SRC is outside the scope of SIPREC.
o Disassociate-time - Disassociate-time for CS-Group shall be
calculated by SRC as the time when the grouping ends
6.2.2. Linkages
The linkages between Communication Session Group class and other
classes is association. A communication Session Group is associated
with RS and CS in the following manner:
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o There is one or more Recording Session objects per Communication
Session Group.
o Each Communication Session Group object has to be associated with
one or more RS [Here each RS can be setup by the potentially
different SRCs]
o There is one or more Communication Sessions per CS Group [e.g.
Consult Transfer]
6.2.3. XML element
Group element is an optional element provides the information about
the communication session group
Each communication session group (CSG)object 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 class and its object in the metadata model
represents Communication Session and its properties needed as seen by
SRC.
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6.3.1. Attributes
A communication Session class has 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
This document does not specify attributes relating to what should
happen to a recording of a CS after it has been delivered to the SRS,
e.g., how long to retain the recording, what access controls to
apply. The SRS is assumed to behave in accordance with policy. The
ability for the SRC to influence this policy is outside the scope of
this document. However if there are implementations where SRC has
enough information, this could be sent as Extension Data attached to
CS
6.3.2. Linkages
A Communication Session is linked to CS-Group, Participant, Media
Stream and Recording Session classes using the association
relationship. Association between CS and Participant allows:
o CS to have atleast two or more participants
o Participant is associated with one or more CS's. This 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. To summarize even if SRC does
not have direct signalling relationships with all participants in
a CS, it should nevertheless create a Participant object for each
participant that it knows about
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.
Association between CS and Media Stream allows:
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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.
Association between CS and RS allows:
o Each instance of RS has Zero or more instances of Communication
Session objects.
o Each CS has to be associated with one more RS [ Here each RS can
be potentially setup by different SRCs]
6.3.3. XML element
Session element provides the information about the communication
session
Each communication session(CS) object is represented by one session
element. Each session element has unique URN UUID attribute which
helps to uniquely identify CS.
Reason element MAY be included to represent the Termination Reason
attribute. 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..* | |
| Associate time |/\__________|Extension Data |
| Disassociate time |\/ | |
| Capabilities | | |
+-------------------------------+ +-----------------+
| 0..* 1..*|
receives| |sends
| 0..* 0..*|
Media Stream
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A Participant class and its objects 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 are cases where a participant can have more than one AoR [
e.g. P-Asserted-ID which can have both SIP and TEL URIs]
o Name - This attribute represents Participant name(SIP display
name) or DN number ( in case it is known)
o Associate-time - associate-time is calculated by SRC as the time
it sees a participant is associated to CS
o Disassociate-time- Disassociate-time is calculated by SRC as the
time it see a participant disassociate from a CS. It is possible
that a given participant can have multiple associate/disassociate
times within given communication session.
o Capabilities - A participant capabilities as defined in RFC 3840
[RFC3840] is an optional attribute that includes the capabilities
of a participant in a CS. This attribute is an attribute of
association of participant to CS. Each participant shall have
Zero or more capabilities. A participant may use different
capabilities depending on the role it plays at a particular
instance. IOW if a participants moves across different CSs ( due
to transfer e.t.c) OR is simultaneously present in different CSs
its role may be different and hence the capability used.
NOTE: How to represent capabilities attribute in XML is an open item.
This document does not specify other attributes relating to
participant e.g. Participant Role, Participant type. An SRC which
has information of these attributes can indicate the same as part of
extension data to Participant from SRC to SRS.
6.4.2. Linkages
The participant class is linked to MS and CS class using association
relationship. The association 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
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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 receives Zero or more streams -
a Supervisor may have side conversation with Agent, while Agent
converses with customer.
6.4.3. XML element
A participant element represents a Participant object.
There MUST be atleast 2 participant for any given session. "send" or
"recv" 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
*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
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Participant
| 0..* 1..*|
receives| |sends
| 0..* 0..*|
+-------------------------+
| Media Stream |
| |
Communication 1..* 0..* +-------------------------+
Session ------------| | +----------+
| Media Stream Reference |1 0..* | |
| Content-type |/\______|Extension |
| CSRC |\/ | Data |
+-------------------------+ +----------+
A Media Stream class (and its objects) has the properties of media as
seen by SRC and sent to SRS. Different snapshots of media stream
object may be sent 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 class has the the following attributes:
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.
o CSRC - The linkage between the participants to its contributing
media stream in a mixed RS stream is provided by CSRC attribute.
Not all SRC may have the capability to determine this and hence
this is a optional attribute. Having this info can allow the SRS
to determine which participants are part(contributors) of
particular parts of the mixed stream.
NOTE: How CSRC can be represented in XML is still an open item. CSRC
attribute is an attribute of media stream to participant association.
Another open items if there is a need for multiple CSRCs. A
participant may have multiple CSRCs - potentially a different one for
each stream in which it participates.
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
restrictions to record
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6.5.2. Linkages
A Media Stream is linked to participant and CS classes using the
association relationship. The details of association with the
Participant are described in the Participant class section. The
details of association with CS is mentioned in the CS section.
6.5.3. XML element
stream element represents a Media Stream object. 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 content attribute if an SRC wishes to send is conveyed in RS SDP.
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. Linkages
Extension data class is linked to other classes using the composition
relationship. An extension data class ( and its objects) is
contained/owned by another Metadata class. Each instance of Metadata
class(except extension data class itself) has
o Zero or more instances of Extension data class
o Each Extension data class is contained/owned by a Metadata class
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.
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extensiondata element MUST include any other XML namespace. Multiple
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. associate-time/disassociate-time
associate-time/disassociate-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 associate-time or disassociate-time MAY exist
in the element namely group, session, participant 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.
6.8. Unique ID format
UUID encoded more densely than the UUID URN (e.g. radix64 of the
binary uuid form defined in RFC 4122 [RFC4122]) SHOULD be used as a
format for Unique ID. How to represent this id in XML is still an
open item.
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.
<?xml version="1.0" encoding="UTF-8"?>
<recording xmlns='urn:ietf:params:xml:ns:recording'>
<dataMode>complete</dataMode>
<group id="urn:uuid:efe3930b-2a31-4e6a-a6ab-203fd7078302">
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<!-- Standardized extension -->
<call-center xmlns='urn:ietf:params:xml:ns:callcenter'>
<supervisor>sip:alice@cisco.com</supervisor>
</call-center>
<mydata xmlns='http://example.com/my'>
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<structure>FOO!</structure>
<whatever>bar</whatever>
</mydata>
</extensiondata>
</group>
<session id="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<group-ref>urn:uuid:efe3930b-2a31-4e6a-a6ab-203fd7078302
</group-ref>
<start-time>2010-12-16T23:41:07Z</start-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</session>
<participant
id="urn:uuid:b2b7c112-5982-469d-9007-6ddbecca64d3"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:partha@blr.cisco.com</aor>
<send>urn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0b</send>
<send>urn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b17</send>
<recv>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</recv>
<recv>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</recv>
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
<participant
id="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:paul@box.cisco.com</aor>
<send>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</send>
<send>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</send>
<recv>urn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b17</recv>
<recv>urn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0b</recv>
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
<stream id="urn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b17"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<csrc>1</csrc>
<label>96</label>
</stream>
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<stream id="urn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0b"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<label>97</label>
</stream>
<stream id="urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a"
session="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103">
<label>98</label>
</stream>
<stream id="urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a"
session="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103">
<label>99</label>
</stream>
</recording>
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
disassociate-time for a participant from a session.
<?xml version="1.0" encoding="UTF-8"?>
<recording xmlns='urn:ietf:params:xml:ns:recording'>
<dataMode>partial</dataMode>
<participant
id="urn:uuid:b2b7c112-5982-469d-9007-6ddbecca64d3"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:partha@blr.cisco.com</aor>
<disassociate-time>2010-12-16T23:41:07Z</disassociate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
</recording>
Partial update of SIP Recording Example XML body
8. XML Schema definition for Recording metadata
This section defines XML schema for Recording metadata document
<?xml version="1.0" encoding="UTF-8"?>
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<xs:schema targetNamespace="urn:ietf:params:xml:ns:recording"
xmlns:tns="urn:ietf:params:xml:ns:recording"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
elementFormDefault="qualified"
attributeFormDefault="unqualified">
<!-- This import brings in the XML language attribute xml:lang-->
<xs:import namespace="http://www.w3.org/XML/1998/namespace"/>
<xs:element name="recording" type="recording"/>
<xs:complexType name="recording">
<xs:sequence>
<xs:element name="datamode" type="dataMode"
minOccurs="0"/>
<xs:element name="group" type="group"
minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="session" type="session"
minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="participant" type="participant"
minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="stream" type="stream"
minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="extensiondata" type="extensiondata"
minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="group">
<xs:sequence>
<xs:element name="associate-time" type="xs:dateTime"
minOccurs="0"/>
<xs:element name="disassociate-time" type="xs:dateTime"
minOccurs="0"/>
<xs:element name="extensiondata" type="extensiondata"
minOccurs="0"/>
</xs:sequence>
<xs:attribute name="id" type="urnuuid"
use="required"/>
</xs:complexType>
<xs:complexType name="session">
<xs:sequence>
<xs:element name="associate-time" type="dateTime"
minOccurs="0"/>
<xs:element name="disassociate-time" type="dateTime"
minOccurs="0"/>
<xs:element name="reason" type="xs:string"
minOccurs="0"/>
<xs:element name="group-ref" type="urnuuid"
minOccurs="0" maxOccurs="1"/>
<xs:element name="extensiondata" type="extensiondata"
minOccurs="0"/>
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</xs:sequence>
<xs:attribute name="id" type="urnuuid"
use="required"/>
</xs:complexType>
<xs:complexType name="participant">
<xs:sequence>
<xs:element name="aor" type="xs:anyURI"
maxOccurs="unbounded"/>
<xs:element name="name" type="xs:string"
minOccurs="0" maxOccurs="1"/>
<xs:element name="send" type="urnuuid"
minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="recv" type="urnuuid"
minOccurs="0" maxOccurs="unbounded"/>
<xs:element name="associate-time" type="xs:dateTime"
minOccurs="0"/>
<xs:element name="disassociate-time" type="xs:dateTime"
minOccurs="0"/>
<xs:element name="extensiondata" type="extensiondata"
minOccurs="0"/>
</xs:sequence>
<xs:attribute name="id" type="urnuuid"
use="required"/>
<xs:attribute name="session" type="urnuuid"
use="required"/>
</xs:complexType>
<xs:complexType name="stream">
<xs:sequence>
<xs:element name="label" type="xs:string"
minOccurs="0" maxOccurs="1"/>
<xs:element name="mode" type="streamMode"
minOccurs="0" maxOccurs="1"/>
<xs:element name="extensiondata" type="extensiondata"
minOccurs="0"/>
</xs:sequence>
<xs:attribute name="id" type="urnuuid"
use="required"/>
<xs:attribute name="session" type="urnuuid"
use="required"/>
</xs:complexType>
<xs:element name='extensiondata'>
<xs:complexType>
<xs:any namespace='##other'
minOccurs='0'
maxOccurs='unbounded'
processContents='lax'/>
</xs:complexType>
<xs:attribute name="id" type="urnuuid"
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use="required"/>
<xs:attribute name="parent" type="urnuuid"
use="required"/>
</xs:element>
<xs:simpleType name="streamMode">
<xs:restriction base="xs:string">
<xs:pattern
value="mixed|separate"/>
</xs:restriction>
<xs:simpleType name="urnuuid">
<xs:restriction base="xs:string">
<xs:pattern
value="urn:uuid:[0-9a-zA-Z]{8}-[0-9a-zA-Z]{4}
-[0-9a-zA-Z]{4}-[0-9a-zA-Z]{4}-[0-9a-zA-Z]{12}"/>
</xs:restriction>
</xs:simpleType>
</xs:simpleType>
<xs:simpleType name="dataMode">
<xs:restriction base="xs:string">
<xs:enumeration value="complete"/>
<xs:enumeration value="partial"/>
</xs:restriction>
</xs:simpleType>
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"
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of [RFC3261].
10. IANA Considerations
This specification registers a new XML namespace, and a new XML
schema.
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 <?xml version="1.0" encoding="UTF-8"?> and its last
line is </xs:schema>
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 and Martin Thompson for validating
the XML schema and providing comments on the same.
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 object 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
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"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) |
+----------------+-----------------------+
| Start Time | |
+----------------+ |
| |
|-------------------+ |
| | |
+---------------+ +---------------+ |
| ParticipantA | | ParticipantB | |
| | | | |
+---------------+ +---------------+ |
| | |
sends | | sends |
| | |
+---------------+ +---------------+ |
|Media Stream A1| |Media Stream B1| |
+---------------+ +---------------+ |
|MediaStream Ref| |MediaStream Ref| |
| | | | |
+---------------+ +---------------+ |
| | |
+-----------------------------------+
12.2. Use case 2: 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.
+-------------------------------+
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| Recording Session (RS) |
+-------------------------------+
| |
| |
| |
| +-------------------------------+
| | 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| | | | |
| +---------------+ | | +---------------+ | | | |
+-|MediaStreamref | | | |MediaStreamRef | | +--------------+ |
| | | | | |-|-------------------|
+---------------+ | | +---------------+ | |
| | | |
+------------+ |sends |sends (hold) |
| sends |(Resume) | |
| (hold) +-------+ +-------+ |
| | | |
+---------------+ +---------------+ +--------------+ |
|Media Stream A2| |Media Stream A3| |MediaStream B2| |
+---------------+ +---------------+ | | |
|MediaStreamref | |MediaStreamRef | +--------------+ |
| | | | |Codec Params | |
+---------------+ +---------------+ | | |
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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 | |
| | | | | |
+---------------+ | +---------------+ |
| | | |
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sends | | | sends |
| | | |
+---------------+ | +---------------+ |
|Media Stream A1| | |Media Stream B1| |
+---------------+ | +---------------+ |
| | | | | |
| | | | 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
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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.
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 |
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| Session (CS) |--+----------------+-----+
+----------------+ | | |
| | | | |
+----------------+ | | |
| | | |
| | | |
| | | |
+---------------+ | | |
| ParticipantA | | | |
| | | | |
+---------------+ | | |
| | | |
sends | | | |
| | | |
+---------------+ | | |
|Media Stream A1| | | |
+---------------+ | | |
|MediaStream Ref|-----|----------------+ |
| | | | |
+---------------+ | | |
| | |
| | |
+-------------+ | |
| | |
| | |
+----------------+ | |
| Participant B | | |
| (in conf) | | |
+----------------+ | |
| | |
sends | | |
| | |
+----------------+ | |
| Media Stream B1|---------------------+ |
+----------------+ sends |
| MediaStream Ref| |
| | +-----------------+
+----------------+ |
| |
|sends |
| |
+-----------------+-------------+------------+
| | | |
| | | |
+------------+ +------------+ +------------+ +-------------+
|participantD| |ParticipantE| |ParticipantF| |Participant G|
+------------+ +------------+ +------------+ +-------------+
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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
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| |
+---------------+ | +---------------+ |
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|MediaStream Ref| | |MediaStream Ref| |
| |---+---| | |
+---------------+ +---------------+ |
|
|
+----------+
+-----------------|
| |
| |
+----------------+ |
| 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. Appendix B: Metadata XML schema Instances
This section describes the metadata model XML instances for different
use cases of SIPREC. For the sake of simplicity the complete SIP
messages are NOT shown here.
13.1. Use case 1: Basic Call
Basic call between two Participants A(Ram) and B(Partha) who are part
of one session. In this use case each participant sends two Media
Streams. Media Streams sent by each participant is received all
other participants of that CS in this use-case. Below is the initial
snapshot sent by SRC that has complete metadata. For the sake of
completeness even snippets of SDP is shown. For the sake of
simplicity these use-cases assume the RS stream is unmixed.
Content-Type: application/SDP
...
m=audio 49170 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:96
a=sendonly
...
m=video 49174 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:97
a=sendonly
...
m=audio 51372 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:98
a=sendonly
...
m=video 49176 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:99
a=sendonly
....
<?xml version="1.0" encoding="UTF-8"?>
<recording xmlns='urn:ietf:params:xml:ns:recording'>
<dataMode>complete</dataMode>
<group id="urn:uuid:efe3930b-2a31-4e6a-a6ab-203fd7078302">
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<!-- Standardized extension -->
<call-center xmlns='urn:ietf:params:xml:ns:callcenter'>
<supervisor>sip:alice@cisco.com</supervisor>
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</call-center>
<mydata xmlns='http://example.com/my'>
<structure>FOO!</structure>
<whatever>bar</whatever>
</mydata>
</extensiondata>
</group>
<session id="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<group-ref>urn:uuid:efe3930b-2a31-4e6a-a6ab-203fd7078302
</group-ref>
<start-time>2010-12-16T23:41:07Z</start-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</session>
<participant
id="urn:uuid:b2b7c112-5982-469d-9007-6ddbecca64d3"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:ram@blr.cisco.com</aor>
<send>urn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0b</send>
<send>urn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b17</send>
<recv>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</recv>
<recv>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</recv>
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
<participant
id="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:partha@blr.sonus.com</aor>
<send>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</send>
<send>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</send>
<recv>urn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b17</recv>
<recv>urn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0b</recv>
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
<stream id="urn:uuid:50000c9b-9191-40a4-8231-5bcbca5e2b17"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<label>96</label>
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</stream>
<stream id="urn:uuid:8b53f3de-da39-4846-93c7-ee5e5f8f6f0b"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<label>97</label>
</stream>
<stream id="urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a"
session="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103">
<label>98</label>
</stream>
<stream id="urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a"
session="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103">
<label>99</label>
</stream>
</recording>
13.2. Use case 2: Hold/resume
Basic call between two Participants A and B. This is the continuation
of above use-case. One of the participants(say A) goes on hold and
then resumes as part of the same session. The metadata snapshot
looks as below
During hold
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Content-Type: application/SDP
...
m=audio 49170 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:96
a=inactive
...
m=video 49174 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:97
a=inactive
...
m=audio 51372 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:98
a=sendonly
...
m=video 49176 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:99
a=sendonly
....
<?xml version="1.0" encoding="UTF-8"?>
<recording xmlns='urn:ietf:params:xml:ns:recording'>
<dataMode>partial</dataMode>
<participant
id="urn:uuid:b2b7c112-5982-469d-9007-6ddbecca64d3"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:ram@blr.cisco.com</aor>
<recv>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</recv>
<recv>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</recv>
</participant>
<participant
id="urn:uuid:b2b7c112-5982-469d-9007-6ddbecca64d3"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:partha@blr.cisco.com</aor>
<send>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</send>
<send>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</send>
</participant>
</recording>
During resume
The snapshot will look pretty much same as Use-case 1.
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13.3. Use case 3: Basic Call with transfer
Basic call between two Participants A and B is connected as in Use-
case 1. Transfer is initiated by one of the participants of by other
entity(3PCC case). SRC sends a snapshot of the participant changes
to SRS. In this instance participant A(Ram) drops out during the
transfer and Participant C(Paul) joins the session. There can be two
cases here, same session continues after transfer or a new session
(e.g. REFER based transfer) is created
Transfer with same session retained - (.e.g. RE-INVITE based
transfer). Participant A drops out and C is added to the same
session. No change to session/group element. C will be new stream
element which maps to RS SDP using the same labels in this instance.
Content-Type: application/SDP
...
m=audio 49170 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:96
a=sendonly
...
m=video 49174 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:97
a=sendonly
...
m=audio 51372 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:98
a=sendonly
...
m=video 49176 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:99
a=sendonly
....
<?xml version="1.0" encoding="UTF-8"?>
<recording xmlns='urn:ietf:params:xml:ns:recording'>
<dataMode>partial</dataMode>
<participant
id="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:partha@blr.sonus.com</aor>
<send>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</send>
<send>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</send>
<recv>urn:uuid:eb424026-6f54-4ef8-a4d0-bb658a1fc6cf</recv>
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<recv>urn:uuid:01c47915-4777-11d8-bc70-0090272ff725</recv>
</participant>
<participant
id="urn:uuid:02d9e6d5-9467-382e-8f9b-9300a64ac3cd"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:paul@box.mit.com</aor>
<send>urn:uuid:eb424026-6f54-4ef8-a4d0-bb658a1fc6cf</send>
<send>urn:uuid:01c47915-4777-11d8-bc70-0090272ff725</send>
<recv>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</recv>
<recv>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</recv>
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
<stream id="urn:uuid:eb424026-6f54-4ef8-a4d0-bb658a1fc6cf"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<label>96</label>
</stream>
<stream id="urn:uuid:01c47915-4777-11d8-bc70-0090272ff725"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<label>97</label>
</stream>
<stream id="urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a"
session="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103">
<label>98</label>
</stream>
<stream id="urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a"
session="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103">
<label>99</label>
</stream>
</recording>
Transfer with new session - (.e.g. REFER based transfer). In this
case new session is part of same grouping (done by SRC).
SRC may send an optional snapshot indicating stop for the old
session.
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<?xml version="1.0" encoding="UTF-8"?>
<recording xmlns='urn:ietf:params:xml:ns:recording'>
<dataMode>Partial</dataMode>
<session id="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<group-ref>urn:uuid:efe3930b-2a31-4e6a-a6ab-203fd7078302
</group-ref>
<stop-time>2010-12-16T23:41:07Z</stop-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</session>
<participant
id="urn:uuid:b2b7c112-5982-469d-9007-6ddbecca64d3"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<disassociate-time>2010-12-16T23:41:07Z</disassociate-time>
</participant>
<participant
id="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103"
session="urn:uuid:855a5ded-8420-456d-a70f-6da1eeaeb425">
<aor>sip:partha@blr.sonus.com</aor>
<disasociate-time>2010-12-16T23:41:07Z</disassociate-time>
</participant>
</recording>
SRC sends a snapshot to indicate the participant change and new
session information after transfer. In this example the same RS is
used.
Content-Type: application/SDP
...
m=audio 49170 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:96
a=sendonly
...
m=video 49174 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:97
a=sendonly
...
m=audio 51372 RTP/AVP 0
a=rtpmap:0 PCMU/8000
a=label:98
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a=sendonly
...
m=video 49176 RTP/AVPF 96
a=rtpmap:96 H.264/90000
a=label:99
a=sendonly
....
<?xml version="1.0" encoding="UTF-8"?>
<recording xmlns='urn:ietf:params:xml:ns:recording'>
<dataMode>partial</dataMode>
<session id="urn:uuid:6DF2D9F8-D4C5-11E0-8DC5-04EE4724019B">
<group-ref>urn:uuid:efe3930b-2a31-4e6a-a6ab-203fd7078302
</group-ref>
<start-time>2010-12-16T23:41:07Z</start-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</session>
<participant
id="urn:uuid:cd27cfa1-2bdd-4830-a653-70374d10f103"
session="urn:uuid:6DF2D9F8-D4C5-11E0-8DC5-04EE4724019B">
<aor>sip:partha@blr.sonus.com</aor>
<send>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</send>
<send>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</send>
<recv>urn:uuid:eb424026-6f54-4ef8-a4d0-bb658a1fc6cf</recv>
<recv>urn:uuid:01c47915-4777-11d8-bc70-0090272ff725</recv>
<associate-time>2010-12-16T23:32:03Z</associate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
<participant
id="urn:uuid:02d9e6d5-9467-382e-8f9b-9300a64ac3cd"
session="urn:uuid:6DF2D9F8-D4C5-11E0-8DC5-04EE4724019B">
<aor>sip:paul@box.mit.com</aor>
<send>urn:uuid:eb424026-6f54-4ef8-a4d0-bb658a1fc6cf</send>
<send>urn:uuid:01c47915-4777-11d8-bc70-0090272ff725</send>
<recv>urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a</recv>
<recv>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</recv>
<associate-time>2010-12-16T23:41:07Z</associate-time>
<extensiondata>
<structure>FOO!</structure>
<whatever>bar</whatever>
</extensiondata>
</participant>
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<stream id="urn:uuid:eb424026-6f54-4ef8-a4d0-bb658a1fc6cf"
session="urn:uuid:6DF2D9F8-D4C5-11E0-8DC5-04EE4724019B">
<label>96</label>
</stream>
<stream id="urn:uuid:01c47915-4777-11d8-bc70-0090272ff725"
session="urn:uuid:6DF2D9F8-D4C5-11E0-8DC5-04EE4724019B">
<label>97</label>
</stream>
<stream id="urn:uuid:f3373a7b-4958-4e55-8820-d03a191fb76a"
session="urn:uuid:6DF2D9F8-D4C5-11E0-8DC5-04EE4724019B">
<label>98</label>
</stream>
<stream id="urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a"
session="urn:uuid:6DF2D9F8-D4C5-11E0-8DC5-04EE4724019B">
<label>99</label>
</stream>
</recording>
14. References
14.1. 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,
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February 2007.
[RFC3840] Rosenberg, J., Schulzrinne, H., and P. Kyzivat,
"Indicating User Agent Capabilities in the Session
Initiation Protocol (SIP)", RFC 3840, August 2004.
[RFC4122] Leach, P., Mealling, M., and R. Salz, "A Universally
Unique IDentifier (UUID) URN Namespace", RFC 4122,
July 2005.
14.2. Informative References
[RFC6341] Rehor, K., Portman, L., Hutton, A., and R. Jain, "Use
Cases and Requirements for SIP-Based Media Recording
(SIPREC)", RFC 6341, August 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.
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
Sonus Networks
Prestige Shantiniketan - Business Precinct
Whitefield Road
Bangalore, Karnataka 560066
India
Email: pravindran@sonusnet.com
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Paul Kyzivat
Unaffiliated
Boxborough, MA
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Ravindranath, et al. Expires March 4, 2012 [Page 45]
