Transcript 3GPP2 IMS Charging Infastructure

3GPP2 IMS Charging
Infrastructure
Presented for 3GPP2 TSG-X
by Nick Mazzarella
of Lucent Technologies
September 25, 2004
1
Contents




3GPP2 IMS Charging
Infrastructure
Scope
3GPP2 Organization
3GPP2 IP Networking Model
Current Rev 0 Charging Structure
 Architecture
 Charging Functions and Correlations
 Basic Flows
 Evolution from Rev 0 to Rev A Charging
 Adding On-Line Charging
 New Charging Functions
 Possible Additional Enhancements
 Harmonization between 3GPP and 3GPP2
 Abbreviations and References
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3GPP2 IMS Charging
Infrastructure
 Charging functions exist in several areas within TSG-X
CSN Work Group – Circuit Domain Charging
PDS Subworking Group – Packet Data Subsystem Charging
MMD Subworking Group - IMS Charging
 This Presentation will focus on Charging in IMS
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3GPP2 IMS Charging
Infrastructure
Scope
Provide architecture and flows for charging for IMS services.
 Objectives




Define principles of charging in an IMS network
Provide a description of the charging architecture
Provide the descriptions of events and triggers for the next
generation of charging data.
Provide charging message flows along with charging data triggers,
message content and format along with the transport of these
messages using the Diameter protocol.
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3GPP2 IMS Charging
Infrastructure
3GPP2 Organizational Context
OP
TSG-X
TSG-S
TSG-C
TSG-A
PSN
CSN
BAN
SC
PDS
MMS
CHARGING
MMD
IMS
MMD Work
Activities
Others
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3GPP2 IP Networking Model
All IP Network Architecture Model (NAM)
Data Bases
OSA-AS
OSA-SCS
Location
Services
Radio
Access
AAA
P
D
Access S
Gateway
SIP-AS
Charging
CSCF
MGCF
PDF
MGW
MRCF
MRFP
IMS
PST
N
IP
Networ
k
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Current Rev 0 Charging Structure
Basic Architecture
Home(A)
Home(B)
BS
AS
AS
AS
AS
MRFC
MRFC
MRFC
MRFC
S-CSCF
S-CSCF
S-CSCF
S-CSCF
I-CSCF
I-CSCF
I-CSCF
I-CSCF
P-CSCF
P-CSCF
P-CSCF
P-CSCF
BGCF
BGCF
BGCF
BGCF
MGCF
MGCF
Rf
AAA
PDSN
BS
Rf
AAA
PDSN
BGCF
1. Off-line IMS Charging architecture for non-roaming scenario
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Current Rev 0 Charging Structure
Basic Architecture
Home(B)
Home(A)
BS
Rf
AAA
AS
AS
AS
AS
MRFC
MRFC
MRFC
MRFC
S-CSCF
S-CSCF
S-CSCF
S-CSCF
I-CSCF
I-CSCF
I-CSCF
I-CSCF
P-CSCF
P-CSCF
P-CSCF
P-CSCF
BGCF
BGCF
BGCF
BGCF
MGCF
Rf
AAA
MGCF
Visited(A)
Visited(B)
Rf
AAA
BS
P-CSCF
P-CSCF
Rf
P-CSCF
P-CSCF
AAA
BS
PDSN
BS
PDSN
2. Off-line IMS Charging architecture for roaming scenario
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Current Rev 0 Charging Structure
 Charging Functions AAA
AAA provides the mechanism to transfer charging (i.e.
Accounting) information from the IMS nodes to the
network operator's chosen Billing System(s).
*Does not define actual end user billing records.
• Main functions:
 The collection of Session charging information from the IMS node
 Intermediate data storage buffering
 The transfer of the charging data to the off-line billing
systems
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Current Rev 0 Charging Structure
Correlation between network elements
 For a session comprising several media components (such as
audio and video), charging data is generated for each media
component and needs to be correlated between network
elements.
Correlation within a session
 The IMS Charging ID may be used to correlate the charging data
between network elements.
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Current Rev 0 Charging Structure
 Charging Correlation Capabilities
To support the correlation of charging information,
the following capabilities apply:

The correlation of charging information for an IMS session is
based on the use of IMS Charging Identifiers (ICIDs).

The first IMS network entity within the SIP signalling path
is responsible for assigning an ICID.

The ICID is passed to all IMS core network entities in the SIP
signalling path. This is performed using SIP signalling.
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Current Rev 0 Charging Structure
 Supported Off-line Interface Types

Rf Offline (Post Paid) Charging Reference Point between an
IMS Network Entity and a AAA
 Rf

IMS nodes (S-CSCF, P-CSCF, I-CSCF, BGCF and MGCF)
apply offline charging via the Rf interface using the AAA
address as received via SIP signaling or the locally
configured AAA address.
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Current Rev 0 Charging Structure
Basic Off-Line Charging Message Flows
Visited Network
UE
Home Network
AAA
(visited)
P-CSCF
AAA
(home)
S-CSCF
1. INVITE
1. INVITE
Service Control
1. INVITE
More SIP signalling
2. 200 OK (Invite)
Service Control
2. 200 OK (Invite)
2. 200 OK
(Invite)
3. Accounting Request [Start]
5. Accounting Request [Start]
Open a P-CSCF AIR
6. Accounting Answer
Open a S-CSCF AIR
4. Accounting Answer
More SIP signalling
SIP Session established
1. Message Sequence Chart for Session Establishment (Mobile Origination)
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Current Rev 0 Charging Structure
Basic Off-Line Charging Message FlowsVisited Network
UE
Home Network
AAA
(visited)
P-CSCF
AAA
(home)
S-CSCF
I-CSCF
1. INVITE
Cx Query with the HSS
1. INVITE
2. Accounting Request [Event]
Open I-CSCF AIR
3. Accounting Answer
Service Control
1. INVITE
1. INVITE
More SIP signalling
4. 200 OK
4. 200 OK
4. 200 OK
5. Accounting Request [Start]
7. Accounting Request [Start]
4. 200 OK
Open P-CSCF AIR
Open S-CSCF AIR
6. Accounting Answer
8. Accounting Answer
More SIP signalling
SIP Session established
2. Message Sequence Chart for Session Establishment (Mobile Termination)
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Current Rev 0 Charging Structure
Basic Off-Line Charging Message FlowsVisited Network
UE
Home Network
AAA
(visited)
P-CSCF
AAA
(home)
S-CSCF
1. BYE
1. BYE
Service Control
2. Accounting Request [Stop]
1. BYE
Close the P-CSCF AIR
4. Accounting Request [Stop]
3. Accounting Answer
Close the S-CSCF AIR
5. Accounting Answer
6. 200 OK
6. 200 OK
6. 200 OK
3. Message Sequence Chart for Session Release – Mobile Initiated
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Evolution to Rev A Charging
 Revision A Charging will provide
standardized functionality for On-line
Charging.
 On-line Charging Architecture has already been defined
in 3GPP2 documentation
 New on-line charging stage 3 flows will have to be
developed

3GPP2 intends to maintain harmonization with 3GPP
Release 6 Charging functionality.

Where applicable, 3GPP2 will adapt some IMS charging
functionality from 3GPP
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Evolution to Rev A Charging
Home(A) + Visited(A)
*
S-CSCF ISC
S-CSCF
In 3GPP
Rel 5 and 6,
a Gateway
has been
added with
an Ro
interface.
3GPP2 may
consider this
as a revision
to Rev 0
Architecture.
Session
Charging
Function
Correlation
Function
Rb
Account
Home(B) + Visited(B)
Bearer
Charging
Function
Bearer
Charging
Function
Correlation
Function
Account
Re
Rating
Function
Ro
MRFC
MRFC
Ro
Session
Charging
Function
ISC S-CSCF
S-CSCF
Re
Rc
Rating
Function
Rc
Charging
information
flow
Re
AS(s)
AS(s)
Rb
Re
Event
Charging
Function
Event
Charging
Function
SCCF
SCCF
CPCF
CPCF
ITS
ITS
Ro
AS(s)
AS(s)
Ro
MRFC
MRFC
ITS
ITS
Online Charging System
Online Charging System
On-line IMS Charging architecture
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Evolution to Rev A Charging
 Added Functions for On-line Charging
 Session Charging Function (SCF)
 Responsible for Session Charging including the session
control such as e.g. session termination.
 Bearer Charging Function (BCF)
 The Bearer Charging Function performs the Bearer
Charging
 Event Charging Function (ECF)
 The Event Charging Function (ECF) performs event-based
charging (content charging). It makes use of the rating
function in order to determine the value of the services
rendered. The ECF may correlate several event-based
charging requests.
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Evolution to Rev A Charging
 Added Functions for On-line Charging
 Subscriber Content Charging Function (SCCF)
 The SCCF is always located in the same operator network as
the account of the subscriber, and handles content charging
requests that are made when the subscriber accesses the
content.
 Content Provider Charging Function (CPCF)
 The CPCF manages the account that is maintained for the
content provider. Upon receipt of a charging request from the
AS/MRFC, the CPCF processes the request and relays it to the
SCCF.
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Evolution to Rev A Charging
 Additional Enhancements
 3GPP2 TSG-X MMD will evaluate additional
charging functions and decide which to include.
 Adoption of consistent terminology between PP/PP2.
e.g. CDRs
Discussion Point: In 3GPP the term CDR stands for
Charging Data Record. In U.S. legacy systems the
acronym stands for Call Detail Records. To eliminate
confusion, 3GPP2 chose the term Accounting
Information Record-AIR in place of CDR for
charging use.
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Evolution to Rev A Charging
Harmonization
Current 3GPP Rel.
5 to 3GPP2 Rev. 0
Correlation
3GPP TS
32.200
V5.5.0
3GPP2 X.P0013007-0
3GPP Ts 32.225
V5.5.0
3GPP2 X.P0013008-0
Harmonization
Possible
Correlation for
3GPP Rel. 6 to
3GPP2 Rev. A *
3GPP TS
32.260 V6.0
3GPP2 X.P0013008-A
3GPP TS
32.296 V6.0
3GPP2 X.P0013012-A
3GPP TS
32.299 V6.0
3GPP2 X.P0013013-A
*Currently under
study in TSG-X MMD
Group
Harmonization between 3GPP and 3GPP2
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Symbols and Abbreviations
Abbreviations
AAA
Authentication, Authorization, and
Accounting
ACA
Accounting-Answer
ACR
Accounting-Request
AIR
Accounting Information Record
AS
Application Server
AVP
ISC
IMS Service Control
MGCF
Media Gateway Control Function
MMD
Multimedia Domain
MRFC
Media Resource Function Controller
MRFP
Multimedia Resource Function
Processor
Attribute Value Pair
OCS
Online Charging System
BCF
Billing Control Function
PDSN
Packet Data Serving Node
BS
Billing System
REL
Release Message
CDR
Charging Data Record
SCCF
Subscriber Content Charging Function
CPCF
Content Provider Charging Function
SDP
Session Description Protocol
CSCF
Call Session Control Function
SIP
Session Initiation Protocol
(I-Interrogating; P-Proxy; and S-Serving)
UE
User Equipment
ECF
Event Charging Function
IAM
Initial Address Message
ICN
IP Connectivity Network
IEC
Immediate Event Charging
IMS
IP Multimedia Subsystem
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References
 3GPP2 X.S0013-007-0 v1.0 IP
Multimedia Subsystem - Charging
Architecture
 3GPP2 X.S0013-008-0 v1.0 IP
Multimedia Subsystem - Accounting
Information Flows and Protocol
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