Description
The Roaming Exchange Network Data Analytics Function (RE-NWDAF) is a deployment variant of the standard 3GPP NWDAF, tailored for the roaming exchange environment. An NWDAF is a 5G core network function defined for data collection and analytics. The RE-NWDAF is specifically instantiated within the infrastructure of a roaming exchange provider (also known as a Data Clearing House or IPX provider), which sits between the home Public Land Mobile Network (HPLMN) and the visited PLMN (VPLMN). Its primary role is to gain a holistic, cross-operator view of roaming traffic and performance, which is not visible to any single operator's NWDAF.
Architecturally, the RE-NWDAF interfaces with various network functions and data sources across the roaming ecosystem. This includes collecting data from the roaming exchange's own systems (e.g., signaling transfer points for Diameter and HTTP/2), as well as potentially subscribing to analytics events from NWDAFs in the HPLMN and VPLMN (via the Nnwdaf_EventsMonitoring service). It can ingest a wide array of data types: signaling messages (e.g., Nudm, Npcf, Namf), user plane events, policy control events, and performance measurements related to roaming sessions.
The RE-NWDAF applies machine learning (ML) models and analytics logic to this federated data set. It works by correlating events from both the home and visited network perspectives for the same subscriber session. This allows it to generate unique insights, such as end-to-end quality of experience (QoE) for a roaming user, identification of anomalies or fraud patterns that span multiple networks (e.g., simultaneous registration attacks), and analytics on roaming traffic trends and hotspots. It can provide its analytics outputs to the roaming exchange's own operational systems, or expose them as a service to subscribing network operators via standardized interfaces, helping them optimize roaming agreements and troubleshoot cross-border service issues.
Purpose & Motivation
The RE-NWDAF was introduced to address the specific data analytics challenges in the global roaming ecosystem. In 5G standalone roaming, the home and visited networks have limited visibility into each other's domains. A home operator's NWDAF sees only the home network control plane and aggregated reports, while the visited network's NWDAF sees only its local context. This creates a blind spot for end-to-end service assurance, fraud management, and optimization of the roaming experience.
Traditional roaming analytics relied on offline processing of billing records (TAP files) or signaling data from a single network's perspective, which was slow and incomplete. The motivation for RE-NWDAF stems from the need for real-time, cross-operator intelligence to support advanced 5G roaming services, network slicing across borders, and stringent service level agreements (SLAs). By leveraging the roaming exchange's unique position as a hub for inter-operator traffic, the RE-NWDAF can synthesize a complete picture. It solves problems like diagnosing the root cause of a roaming session drop (was it in the HPLMN, VPLMN, or the interconnect?), detecting sophisticated fraud that exploits jurisdictional gaps, and providing data-driven insights for negotiating and monitoring roaming partnerships.
Classification
Detected Changes Across Releases
from 3GPP Change RequestsSpecific changes extracted from the „Change history“ tables of 3GPP specifications (699 CRs across 6 releases). Complements the general historical overview above with the evidence-based evolution of this function.
In Release 15, the RE-NWDAF (Roaming Exchange Network Data Analytics Function) was newly introduced as a specialized function within the NWDAF framework to support analytics services in roaming scenarios. The release defined its role in the reference architecture for data analytics, enabling it to operate within the 5G Core network. Specific technical details regarding its interfaces and procedures for data collection and analytics exposure were established, aligning with the general NWDAF capabilities for collecting data from network functions and providing analytics to consumers.
- Correct NWDAF resource TS 29.520CR0014
In Release 16, the RE-NWDAF was introduced as a new Roaming Exchange Network Data Analytics Function, enabling analytics services across PLMNs. The release expanded the types of analytics it could provide, specifically adding support for network performance analytics and NF Load analytics. Furthermore, it included clarifications and enhancements for existing analytics types like UE mobility, abnormal behaviour, and slice load level analytics.
- UE mobility and communication analytics TS 29.520CR0042
- Support of network performance analytics in Nnwdaf_AnalyticsInfo_Request TS 29.520CR0043
- Abnormal behaviour analytics TS 29.520CR0055
- Slice identification for all analytics types TS 29.520CR0104
- NF Load analytics generalities TS 29.520CR0106
- Update the types of analytics events TS 29.520CR0111
+ 74 more changes
In Release 17, the RE-NWDAF function was enhanced with new capabilities for analytics aggregation and coordination across multiple NWDAF instances, including procedures for multiple NWDAF analytics aggregation and time coordination. It also introduced support for new analytics types, such as WLAN performance and redundant transmission experience, and expanded existing analytics for user data congestion and service experience. Furthermore, the release enabled ML model sharing between NWDAF instances and introduced procedures for analytics exposure using the DCCF.
- Analytics ID UE communication and Observed Service Experience Extension to Support Application Related Analytics for RFSP Policy TS 23.288CR0193
- Dispersion Analytics TS 23.288CR0194
- Adding a new analytics WLAN performance TS 23.288CR0197
- Adding Analytics IDs TS 23.288CR0198
- Extensions to User Data Congestion Analytics TS 23.288CR0200
- NWDAF decomposition TS 23.288CR0205
+ 257 more changes
In Release 18, the RE-NWDAF was enhanced to specifically address data and analytics exchange in roaming scenarios, as highlighted in the key issue for roaming. This included architectural support for the NWDAF to provide analytics accuracy information, which represents a performance measure containing an accuracy or loss value and its computation method, thereby improving the reliability of analytics provided between visited and home networks.
- Alignment for UPF event exposure service to NWDAF via the SMF in TS 23.288 TS 23.288CR0551
- Multiple ML Models for an analytics ID TS 23.288CR0559
- Enhancements to Network Performance Analytics to support AIML data traffic policies TS 23.288CR0566
- Enhancement on OSE for NWDAF assisting PCF in making URSP decisions TS 23.288CR0569
- NWDAF updates to assist resource monitoring of AI/ML-based services TS 23.288CR0575
- QoS sustainability analytics enhancement TS 23.288CR0576
+ 255 more changes
In Release 19, the RE-NWDAF introduced support for new analytics types, including Signalling Storm Mitigation and Prevention analytics and QoS Sustainability analytics for UAS. The release also enhanced analytics aggregation with support for processing instructions and extended the Analytics Metadata Info in AnalyticsInfo responses. Furthermore, it defined procedures for Vertical Federated Learning between NWDAFs and AFs, including model training and performance monitoring.
- Registration and Discovery procedure for Vertical Federated Learning among NWDAF(s) and/or AF(s) with NWDAF as the VFL server TS 23.288CR1171
- Support of QoS Substainability Analytics for UAS TS 23.288CR1180
- New analytics ID to support Signalling storm Mitigation and Prevention TS 23.288CR1104
- Support of QoS and policy assistance analytics TS 23.288CR1132
- General training procedure for Vertical Federated Learning between NWDAF(s) and AF(s) TS 23.288CR1134
- NWDAF collects data from LCS to train ML model for AI positioning TS 23.288CR1201
+ 86 more changes
In Release 20, the RE-NWDAF introduced new analytics capabilities specifically for detecting abnormal user plane traffic. This enhancement allows the function to generate and provide analytics related to this specific abnormal traffic use case to consumer network functions.
Explore further
Broader topics and technologies where RE-NWDAF plays a role.
Defining Specifications
3GPP specifications that define or reference RE-NWDAF, with the latest known release. Sourced from the 3GPP document catalog — see methodology.
| Specification | Title | Release |
|---|---|---|
| TS 23.288 vk00 | 5GS Architecture Enhancements for Data Analytics | Rel-20 |
| TS 29.520 vj40 | 5G Network Data Analytics Services Stage 3 | Rel-19 |
| TS 29.552 vj40 | 5G Network Data Analytics Signalling Flows | Rel-19 |