Post on 22-Dec-2015
transcript
January 23-26, 2007• Ft. Lauderdale, Florida
Integrating Charging and Rating into the IMS Platform
Joe Hogan CTO and Founder Openet Telecom
January 23-26, 2007• Ft. Lauderdale, Florida
Agenda
• Introduction• Developing and launching services and applications
quickly and cost effectively• How can existing OSS systems evolve to IMS
architecture• Examining the impact of IMS services on OSS/BSS
systems– Real-Time Charging models as a natural towards IMS– Transferring charging information from the IMS nodes to the
billing system– Utilizing real-time rating for IMS applications
January 23-26, 2007• Ft. Lauderdale, Florida
Rapid service creation and deployment
• IMS architecture facilitates faster service creation and delivery.
• Horizontal service architecture for service delivery:
– Avoids stovepipe challenges previously associated with deploying services
– Improved scalability of service offerings (independent of session control and transport)
– Increased control over service lifecycle– Service transparency
January 23-26, 2007• Ft. Lauderdale, Florida
Evolving to IMS Architecture
Billing Domain
ONLINE CHARGINGOFFLINE CHARGING
WLAN
BGCF
MGCF
MRFC
SIP AS
CRF
AF
CDF
CS -NE
SGSN
CGF
OCSIMS GWF
P -CSCFI-CSCF
S -CSCF
Service -NE
GGSN
TPF
3G Charging Architecture From 3GPP (TS 32.240)
January 23-26, 2007• Ft. Lauderdale, Florida
Existing OSS systems evolution
• Critical that investment in OSS systems is leveraged.• Departure from legacy prepaid platforms and reliance
on vendor defined architectures.• Progression of rating and intelligence capabilities to
the network edge.• Online transaction processing treatment for all
subscribers irrespective of payment method.• ‘Flexible Transactionality’ is at the heart of IMS service
lifecycle control for service creation, aggregation, orchestration, discovery, retirement and delivery.
January 23-26, 2007• Ft. Lauderdale, Florida
Impact of IMS services on OSS/BSS systems
• IMS will deliver innovative services that shall demand the OSS/BSS system handle complex pricing strategies
– Batch based systems fall short of the real-time, low latency processing requirements.
– Network edge rating required.
• Support required for standards based input interfaces (e.g. Rf, Ro).– Diameter rich protocol, non trivial to implement– Interoperability testing critical to success
• Session performance and reliability criteria must be met.
• Irrespective of pre and post payment for services.
• Much greater volumes of usage data from network nodes.
• Increased correlation challenges.
January 23-26, 2007• Ft. Lauderdale, Florida
IMS Online and Offline ChargingOnline Charging• Used for pre-paid account
management.• Subscribers account
balance is checked and authorisation is received in real-time before a service is provided.
• Three types of credit control operation for online charging:– Immediate Event Charging
(IEC) - – Event Charging with Unit
Reservation (ECUR)– Session Charging with Unit
Reservation (SCUR).
Offline Charging• Used for post-paid account
management.• Subscriber is billed after the
service is delivered.• Customer data records are
aggregated and sent to the Billing System in real-time or batch.
• The following types of accounting data can be sent:
– START session accounting
– INTERIM session accounting
– STOP session accounting
– EVENT accounting data.
January 23-26, 2007• Ft. Lauderdale, Florida
IMS Event Based Charging
• Manages charging for single events:– Direct Debit– Service price enquiry– Balance enquiry– Refunds
• Offline event-based charging is performed by the CCF
– A single CDR is generated for the event which can be correlated and sent to the Billing System.
• Online event-based charging is performed by the OCS
– Authorisation, credit control and account balance management are performed for one or more events.
– Communicates with the rating function to determine the value of the requested event.
– Communicates with Credit Control to perform credit reservation and account balance management.
January 23-26, 2007• Ft. Lauderdale, Florida
Session Based Charging
• Manages the charging of a subscriber session such as multimedia gaming, video-conferencing etc.
• Offline session-based charging is performed by the CCF.
– CDR(s) are generated for the session and are aggregated and correlated before being sent to the Billing System.
• Online session-based charging is performed by the OCS
– Authorisation, credit control and account balance management are performed for the session.
– Communicates with the rating function to determine the value of a requested service.
– Communicates with Credit Control to perform credit reservation and account balance management.
– Graceful service termination supported as subscribers account goes to zero.
January 23-26, 2007• Ft. Lauderdale, Florida
Interfaces for Offline Charging
IMS Interface Description
Bi Charging data collection interface between a CCF and a Billing System.
Rf All data communication for offline charging between IMS nodes and the CCF.
Bp Charging data collection interface between a CGF and a Billing System.
Ga Charging data collection interface between a CDR transmitting unit (GGSN/SGSN) and a CDR receiving unit such as a CGF.
January 23-26, 2007• Ft. Lauderdale, Florida
Interfaces for Online Charging
IMS Interface Description
Rb Online Charging Reference Point between Session Charging Function and Correlation Function.
Rc Online Charging Reference Point between Event Charging Function and the Correlation Function.
Re Online Charging Reference Point towards a Rating Function.
Ro Online Charging Reference Point between an Application Server or MRFC and the Event Charging Function.
January 23-26, 2007• Ft. Lauderdale, Florida
Real-Time Charging Models as a natural migration towards IMS
Valuable experience gained with existing charging models in wireless space e.g. packet switched domain.
GnGn GiGi
BTS
MSC SGSN
WAPGW
CiscoCSG
CiscoSESM
PortalVolubillD2CP
GGSN
IntelligentGGSN
GamingServer
MusicServer
Self-HelpServer
UMSServer
Etc.
MMSC
ProQuentMSSP
EDR /RTCUEDR /RTCU
EDR /RTCUEDR /RTCU
EDR /RTCUEDR /RTCU
EDR /RTCUEDR /RTCU
EDR /RTCUEDR /RTCU
CiscoSSG
Gn ProbeNetspira
Internet
IMSMFR, MGCF
CSCF, etc.
CDR
Charging
Customerand
ProductInfo
DWHFraud
PostpaidBilling
BalanceMgmt System(s)
- Billing System- IN Platform- CRM- EtcExternal Rating
- Rating Engine- IN Platform- Billing System- Etc
Rating
G-CDREDR RTCURTCU RTCURTCU RTCURTCU EDRS-CDR RTCURTCU RTCURTCUEDR /RTCUEDR /RTCURTCURTCU RTCURTCU EDR /
RTCUEDR /RTCU
RTCURTCU - Real-Time Content Usage Events
Key Key
- Policy Controller
- Policy Enforcers GGnn GGii
xDR - Post Service Delivery Usage Events
January 23-26, 2007• Ft. Lauderdale, Florida
Transferring charging information from the IMS nodes to the billing system
• Charging interfaces from the IMS core• Session aggregation• Correlation• Account balance management• Distribution
January 23-26, 2007• Ft. Lauderdale, Florida
Charging interfaces from the IMS core
• 3GPP defined Rf interface for offline charging– Based on Diameter Base Protocol Accounting
from IETF AAA WG (RFC3588)– ACR/ACA Messages– 3GPP AVPs
• 3GPP defined Ro interface for online charging– Based on Diameter Credit Control Application from
IETF AAA WG (RFC4006)– CCR/CCA Messages
January 23-26, 2007• Ft. Lauderdale, Florida
Session aggregation
• Session based aggregation required for offline charging to produce P/I/S-CSCF, AS, MRFC, BGCF and MGCF CDRs
• Generated from Diameter ACRs (Start, Interim, Stop)
• Error handling conditions required
January 23-26, 2007• Ft. Lauderdale, Florida
Correlation
• Intra level – using ICID key• Inter level – e.g. with the PS domain• Inter network – using the Inter Operator
Identification (IOI) key
Correlation of IMS usage events is typically required before sending to BS. Correlation is possible on multiple levels:
January 23-26, 2007• Ft. Lauderdale, Florida
Account balance management
For online charging interaction with the subscribers balance is required e.g.
• Query balance• Increment balance• Decrement balance• Set balance to value• Reserve units• Commit reservation• Release reservation
January 23-26, 2007• Ft. Lauderdale, Florida
Distribution
• Bi interface loosely defined• Many different BS vendors most using
proprietary formats for input• Typically file based (push/pull)
January 23-26, 2007• Ft. Lauderdale, Florida
Utilizing real-time rating for IMS applications
• 3GPP have defined rating function within the OCS
• 3GPP online charging demands low latency which mandates network edge rating
• 3GPP services shall more sophisticated and consequently shall require a corresponding level of rating complexity and flexibility
• Rating engines shall need to be able to adapt rapidly to the constant shifting of offered services without dependence on the vendor