3GPP Documentation

Table of contents

• 5G Core Network
  • Architecture
  • Reference Points
  • Services
  • Network Functions and entities
    • AMF (Access and Mobility Management Function)
    • AUSF (Authentication Server Function)
    • BSF (Binding Support Function)
    • CHF (Charging Function)
    • NEF (Network Exposure Function)
    • NRF (NF Repository Function)
    • NWDAF (Network Data Analytics Function)
    • PCF (Policy Control Function)
    • SMF (Session Management Function)
    • UDR (Unified Data Repository)
• Policy and Charging Control
  • OCS (Online Charging System)
  • PCRF (Policy and Charging Rule Function)

5G Core Network

• TS 23.501 - System Architecture for the 5G System
• TS 23.502 - Procedures for the 5G System (5GS)
• TS 23.503 - Policy and Charging Control Framework for the 5G System
• TS 29.501 - Principles and Guidelines for Services Definition
• TS 29.571 - Common Data Types for Service Based Interfaces
• TS 33.501 - Security architecture and procedures for 5G System

Common APIs

• TS 29.571 Common Data Types
• TS 29.122 Common Data Types

Architecture

5G System architecture

PCF/CHF Interfaces

Reference points

Interface	Description
N1	Reference point between the UE and the AMF
N2	Reference point between the (R)AN and the AMF
N3	Reference point between the (R)AN and the UPF
N4	Reference point between the SMF and the UPF
N5	Reference point between the PCF and an AF
N6	Reference point between the UPF and a Data Network
N7	Reference point between the SMF and the PCF
N8	Reference point between the UDM and the AMF
N9	Reference point between two UPFs
N10	Reference point between the UDM and the SMF
N11	Reference point between the AMF and the SMF
N12	Reference point between AMF and AUSF
N13	Reference point between the UDM and Authentication Server function the AUSF
N14	Reference point between two AMFs
N15	Reference point between the PCF and the AMF in the case of non-roaming scenario, PCF in the visited network and AMF in the case of roaming scenario
N16	Reference point between two SMFs (in roaming case between SMF in the visited network and the SMF in the home network)
N17	Reference point between AMF and 5G-EIR
N18	Reference point between any NF and UDSF
N22	Reference point between AMF and NSSF
N23	Reference point between PCF and NWDAF
N24	Reference point between the PCF in the visited network and the PCF in the home network
N27	Reference point between NRF in the visited network and the NRF in the home network
N28	Reference point between PCF and OCS
N31	Reference point between the NSSF in the visited network and the NSSF in the home network
N32	Reference point between SEPP in the visited network and the SEPP in the home network
N33	Reference point between NEF and AF
N34	Reference point between NSSF and NWDAF
N35	Reference point between UDM and UDR
N36	Reference point between PCF and UDR
N37	Reference point between NEF and UDR
N40	Reference point between SMF and the CHF
N50	Reference point between AMF and the CBCF

Services

Producer	Consumer	Service	Standard	API
PCF	AF	Npcf_PolicyAuthorization	TS 29.514	PCF Policy Authorization Service
	SMF	Npcf_SMPolicyControl	TS 29.512	Session Management Policy Control Service
	AMF	Npcf_AMPolicyControl	TS 29.507	Access and Mobility Policy Control Service
	NEF	Npcf_EventExposure	TS 29.523	PCF Event Exposure Service
		Npcf_BDTPolicyControl	TS 29.554	PCF BDT Policy Control Service
NWDAF	PCF	Nnwdaf_EventsSubscription	TS 29.520	Nnwdaf_EventsSubscription Service API
		Nnwdaf_AnalyticsInfo	TS 29.520	Nnwdaf_AnalyticsInfo Service API
CHF	PCF	Nchf_SpendingLimitControl	TS 29.594	Spending Limit Control
	NF	Nchf_ConvergedCharging	TS 32.291	Converged Charging
	NF	Nchf_OfflineOnlyCharging	TS 32.291	Offline Only Charging
UDR	PCF	Nudr_DataRepository	TS 29.504	Unified Data Repository Service
BSF	PCF, NEF, AF	Nbsf_Management	TS 29.521	Binding Support Management Service API
NRF	ALL NF	Nnrf_NFManagement	TS 29.510	NRF NFManagement Service
		Nnrf_NFDiscovery	TS 29.510	NRF NFDiscovery Service
		Nnrf_AccessToken	TS 29.510	NRF OAuth2 Authorization

Network Functions and entities

AMF (Access and Mobility Management Function)

APIs

• Communication
• Event Exposure
• Location
• MT

AUSF (Authentication Server Function)

• TS 29.509 - Authentication Server Services

APIs

• UE Authentication
• SoR Protection

BSF (Binding Support Function)

• TS 29.521 - Binding Support Management Service

CHF (Charging Function)

• TS 29.594 - Spending Limit Control Service
• TS 32.240 - Telecommunication management; Charging management; Charging architecture and principles
• TS 32.255 - Telecommunication management; Charging management; 5G data connectivity domain charging; Stage 2
• TS 32.290 - Telecommunication management; Charging management; 5G system; Services, operations and procedures of charging using Service Based Interface (SBI)
• TS 32.291 - 5G system, charging service; Stage 3

NEF (Network Exposure Function)

• TS 29.551 - 5G System; Packet Flow Description Management Service; Stage 3

APIs

• Packet Flow Description (PFD) Management

NRF (NF Repository Function)

• TS 29.510 - Network Function Repository Services

NWDAF (Network Data Analytics Function)

• TS 29.520 - Network Data Analytics Services

PCF (Policy Control Function)

• TS 29.244 - Interface between the Control Plane and the User Plane nodes
• TS 29.507 - Access and Mobility Policy Control Service
• TS 29.512 - Session Management Policy Control Service
• TS 29.513 - Policy and Charging Control signalling flows and QoS parameter mapping
• TS 29.514 - Policy Authorization Service
• TS 29.523 - Policy Control Event Exposure Service
• TS 29.525 - UE Policy Control Service
• TS 29.554 - Background Data Transfer Policy Control Service
• TS 29.594 - Spending Limit Control Service

SMF (Session Management Function)

• TS 29.502 - Session Management Services
• TS 29.508 - Session Management Event Exposure Service

APIs

• PDU Session
• Event Exposure

UDR (Unified Data Repository)

• TS 29.504 - Unified Data Repository Services
• TS 29.519 - Usage of the Unified Data Repository service for Policy Data, Application Data and Structured Data for Exposure

APIs

• Data Repository
  • Subscription Data
  • Policy Data
  • Exposure Data
  • Application Data

Policy and Charging Control

• RFC 6733 - Diameter Base Protocol

• RFC 8506 - Diameter Credit-Control Application

• TS 23.167 - IP Multimedia Subsystem (IMS) emergency sessions

• TS 23.179 - Functional architecture and information flows to support mission critical communication services

• TS 23.203 - Policy and charging control architecture

• TS 23.228 - IP Multimedia Subsystem (IMS) - Stage 2

• TS 23.401 - General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio Access Network (E-UTRAN) access

• VoLTE Service Description and Implementation Guidelines

OCS (Online Charging System)

• TS 29.219 - Policy and charging control: Spending limit reporting over Sy reference point
• TS 32.240 - Telecommunication management; Charging management; Charging architecture and principles
• TS 32.251 - Telecommunication management;Charging management;Packet Switched (PS) domain charging
• TS 32.260 - IP Multimedia Subsystem (IMS) charging
• TS 32.270 - Multimedia Messaging Service (MMS) charging
• TS 32.274 - Short Message Service (SMS) charging
• TS 32.276 - Voice Call Service (VCS) charging
• TS 32.296 - Telecommunication management; Charging management; Online Charging System (OCS): Applications and interfaces
• TS 32.299 - Diameter charging applications

Interface	Standard
Sy	TS 29.219 - Policy and charging control: Spending limit reporting over Sy reference point
Ro - Gy	TS 32.251 - Telecommunication management;Charging management;Packet Switched (PS) domain charging
Ro / Rf	TS 32.299 - Diameter charging applications

PCRF (Policy and Charging Rule Function)

• TS 29.211 - Rx Interface and Rx-Gx signalling flows
• TS 29.213 - Policy and charging control signalling flows and Quality of Service (QoS) parameter mapping
• TS 23.380 - IMS Restoration Procedures

Interface	Standard
Gx	TS 29.212 - Policy and Charging Control (PCC); Reference points
Rx	TS 29.214 - Policy and charging control over Rx reference point
Sy	TS 29.219 - Policy and charging control: Spending limit reporting over Sy reference point