5G network reference point architecture | NG1 to NG15 interfaces
This page describes 5G network reference point architecture. This 5G network architecture mentions various reference points or interfaces (NG1, NG2, NG3, NG4, NG5, NG6, NG7, NG8, NG9, NG10, NG11, NG12, NG13, NG14, NG15) used between functional blocks of 5G NR network.
Introduction:
The 5G stands for 5th generation of wireless technology. It follows 3GPP road map from which LTE i.e. 4th generation wireless
technology and LTE advanced have been developed.

• The figure-1 depicts 5G NR overall architecture. This is as defined in the 3GPP TS 38.300 specification.
• gNB node providing NR user plane and control plane protocol terminations towards the UE, and connected via the NG interface to the 5GC.
• ng-eNB node providing E-UTRA user plane and control plane protocol terminations towards the UE, and connected via the NG interface to the 5GC.
Refer 5G basic tutorial >>.
5G NG1 to NG15 interfaces | 5G NG1 to NG15 Reference Points

The figure-2 depicts 5G reference point architecture. Following table mentions functional description of 5G NG1 to NG15 Reference Points or interfaces.
5G reference points or 5G interfaces | Function description |
---|---|
NG1 | Between UE and AMF (Access and Mobility Management Function) |
NG2 | Between RAN (Radio Access Network) or gNB (i.e. 5G base station) and AMF |
NG3 | Between RAN or gNB (i.e. 5G base station) and UPF (User Plane Function) |
NG4 | Between SMF (Session Management Function) and UPF |
NG5 | Between PCF (Policy Control Function) and AF (Application Function). |
NG6 | Between UPF and DN (Data Network) |
NG7 | NG7 is reference point between SMF and PCF NG7r is reference point between vPCF and hPCF |
NG8 | Between Unified Data Management (UDM) and AMF |
NG9 | Between two core UPFs |
NG10 | Reference point between UDM and SMF |
NG11 | Between SMF and SMF |
NG12 | Between AMF and AUSF (Authentication Server Function) |
NG13 | Between UDM and AUSF |
NG14 | Between two AMFs |
NG15 | • Between PCF and AMF (in Non-roaming scenario) • Between V-PCF and AMF (in Roaming scenario) |
NG16 | Between two SMFs (Roaming between V-SMF and H-SMF) |
Reference: 3GPP specification
5G NR Numerology | 5G NR Terminology
5G NR Control channels | 5G NR Traffic Channels | 5G NR Reference Signals and sequences
5G TECHNOLOGY RELATED LINKS
This 5G tutorial also covers following sub topics on the 5G technology:
5G basic tutorial
5G Frequency Bands
5G millimeter wave tutorial
5G mm wave frame
5G millimeter wave channel sounding
Difference between 4G and 5G
5G testing and test equipments
5G network architecture
5G NR Physical layer
5G NR MAC layer
5G NR RLC layer
5G NR PDCP layer