1. AMF: Access and Mobility Management Function
2. SMF: Session Management Function
3. PCF: Policy Control Function
4. UDM: Unified Data Management
5. AUSF: Authentication Server Function
6. NSSF: Network Slice Selection Function
7. NEF: Network Exposure Function
8. NRF: Network Repository Function
9. SEPP: Security Edge Protection Proxy
10. UPF: User Plane Function
11. UDR: Unified Data Repository
12. CHF: Charging Function
13. NWDAF: Network Data Analytics Function
14. SMSF: SMS Function
15. LMF: Location Management Function
16. AF: Application Function
17. GMLC: Gateway Mobile Location Center
18. 5G-EIR: 5G Equipment Identity Register
19. N3IWF: Non-3GPP Interworking Function

User Plane Function

UPF - User Plane Function

• Routes user data, enforces QoS, and performs traffic optimization

Data Management & Charging

UDR - Unified Data Repository

• Central storage for subscriber data (policies, profiles).

CHF - Charging Function

• Manages charging, billing, and usage reporting.

Control Plane Functions

AMF - Access and Mobility Management Function

• Manages device registration, mobility and connection states.

SMF - Session Management Function

• Handles session establishment, IP allocation, and UPF control.

PCF - Policy Control Function

• Enforces dynamic policies for QoS, slicing, and charging.

UDM - Unified Data Management

• Manages subscriber data (authentication, profiles)

AUSF - Authentication Server Function

• Performs 5G-AKA authentication for devices.

NSSF - Network Slice Selection Function

• Assigns network slices based on device/service requirements.

NEF - Network Exposure Function

• Exposes network APIs to third-party applications (e.g. IoT, edge computing).

NRF - Network Repository Function

• Service discovery and registration for 5GC functions.

SEPP - Security Edge Protection Proxy

• Secures signaling between different operator networks (inter-PLMN).

Analytics & Specialized Functions

NWDAF - Network Data Analytics Function

• Provides AI/ML-driven insights (e.g. traffic prediction, anomaly detection).

SMSF - SMS Function

• Supports SMS services over 5G.

LMF - Location Management Function:

• Determines device location (e.g. emergency services)

AF - Application Function:

• Represents third-party applications (e.g. video streaming, IoT) that interact with 5GC via the NEF to request services (e.g. QoS adjustments).
• AF is critical for enabling network-aware applications (e.g. adjusting bandwidth for a video call)

GMLC - Gateway Mobile Location Center:

• Retrieves device location for external application (e.g. emergency services, logistics). While inherited from LTE, it interfaces with 5GC's LMF for location data.
• GMLC bridges 5GC with legacy location services but relies on LMF for actual positioning in 5G.

5G-EIR - 5G Equipment Identity Register

• Validates device identities (IMEI) to block unauthorized/stolen devices.
• 5G-EIR replaces LTE's EIR but serves a similar anti-fraud role.

N3IWF - Non-3GPP Interworking Function

• Connects untrusted non-3GPP networks (e.g., Wi-Fi, satellite) to 5GC via secure tunnels (IPsec) and interfaces with AMF/UPF.