Supported Interfaces

This section describes the interfaces supported between the SMF and other network functions in the 5GC.

  • Diameter—Interface that provides framework for services that require Access, Authorization, and Accounting (AAA) or Policy support across IP-based networks.

  • GTP—Uses the N9 interface as the reference point between two core UPFs.

  • Gx—Interface between SMF and PCRF.

  • Gy—Interface between SMF CTF and OCS Charging Data Function (CDF).

  • N1/NAS—Reference point between the UE and AMF.

  • N2/NGAP—Reference point between the RAN and AMF.

  • N4—Reference point between the SMF and UPF.

  • N7—Reference point between the SMF and PCF.

  • N10—Reference point between the UDM and SMF.

  • N11—Reference point between the AMF and SMF.

  • N40—Reference point between the SMF and CHF.

  • Nnrf—Interface displayed by NRF on 3GPP 5G system architecture.

  • RADIUS—Interface that manages network access.

  • S2b—Interface between the PGW-C and ePDG.

  • S5—Interface between the PGW-C and S-GW.

  • SBA—Interface for NFs to communicate with each other.

For details on the supported interfaces, see the Interfaces Support chapter.