Network Exposure Function

In Release 15, the NEF was formally introduced with core services including Event Exposure and Structured Data for Exposure, establishing subscription and notification mechanisms. It defined a common API framework and detailed architectures for both non-roaming and roaming situations, while also specifying services like Chargeable party and AFsessionWithQoS. The release included numerous corrections and refinements to its service descriptions, OpenAPI definitions, HTTP error responses, and resource management features such as notification of resource deletion.

• Subscription for Structured Data for Exposure TS 29.519CR0022
• Non-roaming Architecture for Network Exposure Function in reference point representation TS 23.501CR0073
• Supporting Common API framework for NEF TS 23.501CR0124
• Subscription status notification for Event Exposure service TS 23.501CR0273
• NEF Services TS 23.501CR0367
• Network Exposure in Roaming Situations TS 23.501CR0493

+ 15 more changes

In Release 16, the NEF was enhanced with new capabilities including the integration with CAPIF for API management, the introduction of an Interworking-NEF (I-NEF) for service exposure in roaming and interworking scenarios, and support for NEF-based infrequent small data transfer via NAS. It also gained new services for provisioning service-specific parameters, exposing NWDAF analytics, and supporting enhanced location services and coverage restriction control.

• Integrated CAPIF with 3GPP EPS and 5GS network exposure TS 23.222CR0021
• 3rd party trust domain with network exposure and charging aspects of 3GPP systems TS 23.222CR0062
• Introduction of NEF based infrequent small data transfer via NAS TS 23.501CR0890
• Introduction of the SCEF+NEF TS 23.501CR0828
• NEF service for service specific parameter provisioning TS 23.501CR0878
• NEF service for NWDAF analytics TS 23.501CR0964

+ 24 more changes

In Release 17, the NEF's capabilities were expanded to support network exposure to Edge Application Servers (EAS) via a Local NEF and to expose time synchronization as a service. It also gained new functionalities for exposing UE application events and QoE metrics via an Application Function, and its service was utilized for the SEAL location service. Furthermore, enhancements were made for local NEF selection and discovery, and parameters were added for partitioning criteria in AF and SMF event exposure.

• Utilize NEF location service for SEAL LM TS 23.434CR0076
• KI#3A - TSC Assistance container determined by NEF TS 23.501CR2619
• KI#3B-1: Exposure of Time synchronization as a service TS 23.501CR2629
• Adding some parameters for local NEF selection TS 23.501CR2656
• Alignment of NWDAF discovery of data exposure capability in TS 23.501. TS 23.501CR2759
• Newly added parameters for Local NEF discovery TS 23.501CR2856

+ 70 more changes

In Release 18, the NEF saw significant enhancements focused on exposing new network capabilities and events to external applications. Key introductions included support for NAT (Network Address Translation) exposure, UPF event exposure for TSC (Time Sensitive Communication) management, and direct QNC (QoS Notification Control) exposure by the UPF. Furthermore, new exposure capabilities were defined for XR services, AI/ML services, NWDAF-assisted application detection, and the exposure of RAN measured data rates.

• TS 23.501 Enhancing External Exposure of Network Capability TS 23.501CR3715
• Update for UPF registration and event exposure related context concluded in FS_UPEAS TS 23.501CR3723
• Enhancements of PCF Services and NEF Services TS 23.501CR3796
• UPF event exposure service for TSC management TS 23.501CR3720
• Support of NAT exposure in 23.501 according to the conclusion in UPEAS TS 23.501CR3825
• Introduction of 5GS Information Exposure TS 23.501CR3887

+ 85 more changes

In Release 19, the NEF saw significant enhancements focused on new exposure capabilities and event reporting. Key additions included the exposure of user-sensitive information, value-added UE location, NAT information, static UE IP assignment details, and available data rate. The release also expanded event exposure support for UPF events using a UE's IP address, during UPF relocation and session release, and for AMF events supporting on-demand LCS broadcast, alongside comprehensive new support for energy consumption information exposure.

• Slice-based service API exposure TS 23.222CR0131
• Exposure of User Sensitive Information TS 23.222CR0228
• Exposure of value-added UE location information TS 23.434CR0311
• Adding the NAT information exposure and Packet Inspection functionality in the UPF NF profile TS 23.501CR5420
• Exposure enhancements for static UE IP address assignment and 5G VN group's User Plane Security Policy TS 23.501CR5492
• Supporting direct subscription of UPF event exposure using UE's IP address TS 23.501CR5540

+ 74 more changes

In Release 20, the NEF introduced new exposure capabilities specifically for energy-related information and policy. This included the exposure of an Energy Consumption Category and metrics such as Energy Consumption per bit via the Enabling Interface (EIF). Furthermore, the release defined the corresponding reference architecture for API exposure of this energy consumption information and its associated policy control.

• Introduction of EIF exposure of Energy Consumption Category and of the Energy Consumption per bit. TS 23.501CR6487
• Energy Consumption information exposure and policy control TS 23.501CR6508
• API exposure Reference architecture TS 23.700CR0003