Roaming Capability Invocation Without Centralized I-NEF

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The deployment of a centralized Intermediate-NEF between visited and home networks during terminal roaming incurs high costs due to the need for additional devices and interaction interfaces in 5G networks.

Innovation Solution

A method is provided where a visited network exposure function (V-NEF) determines its capability to process a capability invocation request, and if capable, performs interactive communication with home network elements; otherwise, the home NEF communicates directly with these elements, eliminating the need for a centralized I-NEF.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a centralized Intermediate-NEF is deployed between visited and home networks to enable roaming communication, then roaming capability invocation is achieved, but device deployment costs and interface complexity increase

Engineering Contradiction:
Improveroaming capability invocationVSAvoiddeployment of additional devices and interfaces
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the I-NEF from the mandatory architecture and makes it optional. The V-NEF is equipped with direct communication capabilities with home network elements (UDM, PCF, AMF, SMF), allowing capability invocation without the intermediate I-NEF component in many scenarios.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The V-NEF performs self-capability assessment to determine whether it can directly process capability invocation requests. When the V-NEF determines it has the necessary capabilities, it handles requests autonomously without requiring home NEF mediation, reducing overall system complexity.

Inventive Principle:
Principle #25Self-service

2Reliability

If a centralized I-NEF is deployed to enable roaming communication, then network capability invocation is achieved, but deployment costs increase

Engineering Contradiction:
Improvenetwork capability invocationVSAvoiddeployment costs
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent removes the mandatory I-NEF deployment requirement, extracting this costly intermediate component from the architecture. The V-NEF is designed with direct access capabilities to home network elements, eliminating the need for expensive intermediate deployment in most scenarios.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent employs a lightweight capability assessment mechanism at the V-NEF that determines on-demand whether direct processing is possible. This avoids the permanent, expensive infrastructure of a centralized I-NEF while maintaining functionality when needed.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

3Device complexity

If the V-NEF directly communicates with home network elements, then interaction interface complexity is reduced, but capability compatibility may be compromised

Engineering Contradiction:
Improveinteraction interfaceVSAvoidcapability compatibility
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The V-NEF performs preliminary capability self-assessment before processing capability invocation requests. This advance check ensures the V-NEF only handles requests it is compatible with, maintaining reliability while enabling direct communication interfaces.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent introduces the home NEF as a conditional intermediary that steps in only when the V-NEF's self-assessment indicates incompatibility. This selective mediation maintains capability compatibility while preserving the benefits of simplified direct interfaces for compatible scenarios.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP4723699A1Roaming communication method, communication network device, system, and storage medium
Publication Date: 2026.04.08 ZTE CORP
  • EP4723699A1 patent drawingFigure 1~3\
  • EP4723699A1 patent drawingFigure 4~7
  • EP4723699A1 patent drawingFigure 8

AI summary

Embodiments of the present invention provide a method for roaming communication, a communication network device, a system, and a storage medium, and belongs to the technical field of communications. The method comprises: in response to a terminal being in a roaming state, receiving, by a visited network exposure function (V-NEF), a capability invocation request initiated by a home application function (H-AF); determining whether the V-NEF is capable of processing the capability invocation request; if yes, performing, by the V-NEF, interactive communication with a home network element function to complete capability invocation, wherein the home network element function comprises at least one of a unified data management (UDM) function or a policy control function (PCF); and if no, performing, by a home NEF, interactive communication with the home network element function to complete the capability invocation.