Rc (TS 132.296) and Sy (TS 29.219) Interface

1. Rc (TS 132.296) and Sy (TS 29.219) Interface Session #2 Author: Victor I. Fajardo Date: Sept. 27, 2013 Diameter Session #2

2. Agenda • Overview of the OCS (On-line Charging system) • Online vs. Offline charging • Functional requirements • Service consumption rating • Account balance management • Charging transaction control • Charge support • Correlation function Diameter Session #2

3. Agenda • The Sy Interface • Policy Enforcement Overview • Spending Limit report (Request, Notification and Cancelation) • Protocol Details • Message Formats • Message Flows • The Rc Interface • Account Balance Management Overview • Debit operation • Account reservation • Refund • Balance Query • Protocol Details • Message Formats • Message Flows Diameter Session #2

4. OCS Overview (Architecture) Diameter Session #2

5. Online vs. Off-line Charging • Offline charging is applied to users who pay for their services periodically (e.g., at the end of the month) • Online charging (credit-based charging) is used for prepaid services • Real-time credit control • Both real-time and prepaid maybe applied to the same session • Charging function addresses • Addresses distributed to each IMS entities and provide a common location for each entity to send charging information • Charging Data Function (CDF) addresses are used for offline billing and Online Charging Function (OCF) for online billing. Diameter Session #2

6. Offline Charging • SIP network entities (P-CSCF, I-CSCF, S-CSCF, BGCF, MRFC, MGCF, AS) involved in the session uses Rf to send accounting information to a CDF • CDF will collect all this information, and build a Call Detail Record (CDR), which is sent to the billing system (BS) of the domain • Each session carries an IMS Charging Identifier (ICID) as a unique identifier generated by the first IMS entity involved in a SIP transaction and used for the correlation with CDRs • Each domain has its own charging network • Billing systems in different domains will also exchange information, so that roaming can be applied Diameter Session #2

7. Online Charging • The S-CSCF talks to a Session Charging Function (SCF) which looks like a regular SIP application server • The SCF can signal the S-CSCF to terminate the session when the user runs out of credits during a session • The AS (Application Server) use the Ro interface to the Online charging function • Immediate Event Charging (IEC) • The number of credit units is immediately deducted from the user's account • AS is then authorized to provide the service. • The service is not authorized when not enough credit units are available • Charging with Unit Reservation (ECUR) • The number of credit units in the user's account is reserved. • AS is then authorizes • After the service is over, the number of spent credit units is reported and deducted from the account; the reserved credit units are then cleared Diameter Session #2

8. OCS Functions • Event Based Charging Function • On the bearer level • It controls the bearer usage in the network, e.g. SMS • On the subsystem level • It controls the resource availability in network, e.g. it has the ability to grant or deny the resource usage • On the service level • it has the ability to grant or deny the service usage in the network • Session Based Charging Function • On the bearer level • It controls the bearer usage in the network, e.g. in terms of time or volume granted • On the subsystem level • Grant or deny a session setup request and to terminate an existing session • On the service level • It controls service availability in the network, e.g. it has the ability to grant or deny a usage of a service Diameter Session #2

9. OCS Rating Functions • Rating for network- and external services and applications (session, service, event) before and after service delivery; • Cross-product and cross-channel discounts, benefits and allowances. • The Rating Function must be able to handle a wide variety of rateable instances, such as: • Rating of volume (in terms of granted units or money, e.g. based on charging initiated by an access network entity); • Rating of time (in terms of granted units or money, e.g. based on charging initiated by a SIP application); • Rating of events (e.g. based on charging of web content or MMS) Diameter Session #2

10. The Sy Interface • The Sy reference point is located between the Policy and Charging Rules Function (PCRF) and the OCS • Enables transfer of policy counter status information relating to subscriber spending from OCS to PCRF • Request of policy counter status reporting from PCRF to OCS and subscribe to or unsubscribe from spending limit reports (i.e. notifications of policy counter status changes). • Notification of spending limit reports from OCS to PCRF. • Cancellation of spending limit reporting from PCRF to OCS Diameter Session #2

11. Diameter Session #2

12. Sy Spending Limit Request and Answer Commands Diameter Session #2

13. Sy Spending Status Notification Request and Answer Commands Diameter Session #2

14. Sy Specific Diameter AVPs Diameter Session #2

15. Sy Initial/Intermediate Report Message Flows H-PCRF OCS 1. Policy decision depends on spending info 2. Diameter SLR 3. Diameter SLA Diameter Session #2

16. Sy Initial/Intermediate Reports Request AVPs Diameter Session #2

17. Sy Initial/Intermediate Reports Response AVPs Diameter Session #2

18. Sy Intermediate Spending Limit Report Message Flows H-PCRF OCS 1. Additional or fewer policy counters are determined to be relevant for policy decision 2. Diameter SLR 3. Diameter SLA 4. Policy decision depends on spending info Diameter Session #2

19. Sy Spending Limit Report Request Sy Spending Limit Report Response Diameter Session #2

20. Sy Final Spending Limit Report Message Flows H-PCRF OCS 1. Decision to unsubscribe to changes in the Policy-Counter-Status 2. Diameter STR 3. Diameter STA Diameter Session #2

21. Sy Spending Limit Report (Status Change) Message Flows H-PCRF OCS 1. Policy-Counter-Status change (e.g. Threshold reached) 2. Diameter SNR 3. Diameter SNA Diameter Session #2

22. Sy Final Spending Limit Report Request Sy Final Spending Limit Report Response Diameter Session #2

23. The Rc Interface • The Rc reference point is located between the OCF (Online Charging Function) and ABMF (Account Balance Management Function) • ABMF manages subscribers credits • Supports query, credit, debit, refunds etc. • Rc allows the OCS to perform: • Immediate account debit operation • Event based account reservation debit/release operation • Session based account reservation debit/release operation • Account refund • Account balance query Diameter Session #2

24. Rc Credit-Control Request and Answer Commands Diameter Session #2

25. Rc Event Description Diameter Session #2

26. Rc Specific Diameter AVPs Diameter Session #2

27. Rc Immediate Account Debit Message Flows Diameter Session #2

28. RcEvent based Account Reservation with Debit or Release Message Flows Diameter Session #2

29. RcSession based Account Reservation with Debit or Release Message Flows Diameter Session #2

30. RcAccount Refund Message Flows Diameter Session #2

31. RcBalance Message Flows Diameter Session #2

32. Questions ? Diameter Session #2