4 Overview

29.5443GPP5G SystemRelease 18Secured Packet Application Function (SP-AF) servicesStage 3TS

4.1 Introduction

Within the 5GC, the SP-AF offers services to the UDM and to the SOR-AF via the Nspaf service based interface.

The UDM or SOR-AF shall make use of the SP-AF services when it needs to protect UE parameters for which the final consumer is the USIM (see 3GPP TS 33.501 [8] clause 6.15.2.1).

Figure 4.1-1 provides the reference model with focus on the SP-AF.

NOTE: The generation of the secured packet and the definition of the storage and handling of OTA keys or other sensitive data are out of scope of this document. For more details, refer to 3GPP TS 23.040 [18] and 3GPP TS 31.115 [16].

Figure 4.1-1: Reference model – SP-AF