Policy and Charging Control in 5G SA network

Course outline : Mobile operators need to control their customers’ mobile data usage in order to accept or reject IP flows. In addition, the operator must provide QoS for the operator’s IP services (e.g., Voice over IP, mobile TV, streaming, etc.). The concept of “Policy Control” is related to the authorization/blocking and QoS functions of IP flows. The concept of “Charging Control” relates to the charging of IP flows. The architecture implementing these controls is called PCC (Policy and Charging Control).
By implementing Quality of Service (QoS) and charging control, mobile service operators can:
• guarantee bandwidth for high-revenue services,
• achieve market segmentation,
• ensure appropriate network usage by service flows,
• block or degrade service flows that impair network performance,
• guarantee the best possible user experience.
The objective of this training is to:
• Review the PCC architecture for 2G to 5G NSA mobile data networks
• Present the PCC architecture in the context of 5G SA without roaming and with roaming scenarios (local breakout and home routed)
• Describe the different PCF services
• Present the different types of policies:
o AM Policy
o UE Policy
o SM Policy
o ATSSS Policy
o Background Data Transfer Policy
o Traffic Influence Policy
o AM Influence Policy
• Describe the different CHF services

1. PCC Overview in 4G
1.1. PCC services in 4G: fair use, prepaid, anti-bill shock, roaming data pass, QoS for VoLTE/VoWiFi, etc.
1.2. PCC architecture in 4G
1.3. PCEF, PCRF, OCS, OFCS
1.4. DIAMETER-based interfaces: Gx, Gy, Sy
1.5. Definition of PCC rules
1.6. Example of a “fair use” scenario in 4G PCC and associated call flow

2. Policy and Charging Control in 5G SA with the PCF and CHF Functions
2.1. Policy Control requirements in 5G SA
2.2. Comparison between 4G policy control and 5G SA policy control
2.3. Npcf Services
2.3.1. Npcf_AMPolicyControl: provides the AMF with mobility management policies.
2.3.2. Npcf_AMPolicyAuthorization: allows the AF and the NEF to influence access and mobility policies for a UE.
2.3.3. Npcf_PolicyAuthorization: authorizes and creates policies, upon AF request, for the PDU session to which the AF session is related.
2.3.4. Npcf_SMPolicyControl: provides the SMF with SM policies related to a PDU session.
2.3.5. Npcf_BDTPolicyControl: provides the NEF with the data transfer policy negotiated between the AF and the PCF.
2.3.6. Npcf_UEPolicyControl: provides the UE with UE policy via the AMF.
2.3.7. Npcf_EventExposure: allows other AFs and the NEF to subscribe to event notifications supported by the PCF (e.g., Application Start, Application Stop).
2.4. Converged Charging
2.4.1. Converged Charging Architecture
2.4.1.1. Charging Trigger Function (CTF), Converged Charging System (CCS), Billing Domain (BD)
2.4.1.2. CCS: CHF, ABMF, CGF, RF
2.4.1.3. Nchf, Rc, Re, Ga, Bx interfaces
2.4.2. Nchf Services
2.4.2.1. Nchf_ConvergedCharging
2.4.2.2. Nchf_OfflineOnlyCharging
2.4.2.3. Nchf_SpendingLimitControl
2.4.2.4. Example of a fair use service
2.5. Network Slice Charging
2.5.1. Slice Charging Architecture
2.5.1.1. CEF: Charging Enablement Function
2.7. PCC Architecture in roaming situation
2.7.1. vAMF, vSMF, hSMF, vPCF, hPCF, vCHF, hCHF
2.7.2. Point-to-point interfaces: N24, N40, N41, N42, N46, N47, N107
2.7.3. vAMF → vPCF: AM Policy
2.7.4. vAMF → vPCF → hPCF: UE Policy
2.7.5. hSMF → hPCF: SM Policy in home routed mode
2.7.6. vSMF → vPCF → hPCF: SM Policy in local breakout mode
2.7.7. vSMF → vCHF for inter-operator charging in roaming
2.7.8. hSMF → hCHF: charging control in home routed mode
2.7.9. vSMF → hCHF or vSMF → vCHF → hCHF: charging control in local breakout mode
2.7.10. vSMSF → vCHF

3. Policy Data in the UDR

4. AM Policy
4.1. Registration Procedure
4.2. AM Policy Association between AMF and PCF or between vAMF and vPCF
4.3. AM Policy

5. UE Policy Set
5.1. URSP: UE Route Selection Policy

6. Definition of the PDU Session
6.1. PDU Session Establishment
6.2. QoS Flows
6.2.1. QoS Flow Parameters: 5QI, ARP, GFBR, Session-AMBR
6.2.2. Concept of QFI (Quality of Service Flow Identifier)
6.3. PDU Session with Multiple PDU Session Anchors (PSAs)
6.4. Multi-Access PDU Session
6.4.1. ATSSS Rules included in the SM Policy
6.5. Relationship between PDU Session and CHF

7. Session Management in 5G PCC
7.1. Definitions of QoS Rules, QoS Profiles, PCC Rules
7.2. SM Policy Association between SMF and PCF
7.3. Definition of Packet Detection Rules, QoS Enforcement Rules, Usage Reporting Rules, Session Reporting Rules
7.4. Example of a 5G SA fair use scenario and associated call flow

8. Other Policies
8.1. Background Data Transfer Policy Negotiation and Background Data Transfer Policy
8.2. Traffic Influence Policy
8.3. AM Influence Policy