WLAN Access Network Selection for Home PLMN PDN-GW Connectivity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current WLAN Access Network selection procedures fail to provide appropriate network selection for User Equipment (UE) requiring access to a Packet Data Network Gateway (PDN-GW) in both the Home PLMN and Visited PLMN, leading to potential service disruptions and performance issues, especially for services requiring IP address preservation.

Innovation Solution

A method for WLAN Access Network selection by User Equipment (UE) that includes selecting a WLAN Access Network with connectivity to at least one PDN-GW in the Home PLMN, utilizing information on connectivity to PDN-GWs, and configuring the UE with indicators for HPLMN PDN-GW access requirements to ensure IP address preservation across both Home and Visited PLMNs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If current WLAN Access Network selection procedures are used, then the selection process is simple, but it fails to provide appropriate network selection for UEs requiring access to PDN-GW in both Home PLMN and Visited PLMN

Engineering Contradiction:
Improveservice continuityVSAvoidnetwork selection complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies preliminary action by having the UE retrieve and store connectivity information about PDN-GWs in Home PLMN before actually needing to establish a connection. This pre-retrieved information is then used during network selection to quickly identify suitable WLAN Access Networks without requiring complex real-time queries, thus maintaining simplicity while improving reliability.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements feedback mechanisms where the UE continuously monitors and stores connectivity information about available PDN-GWs and WLAN networks. This feedback loop allows the UE to make informed network selection decisions based on actual connectivity status, ensuring reliable service continuity while keeping the selection process straightforward through iterative refinement rather than complex algorithms.

Inventive Principle:
Principle #23Feedback

2Reliability

If UE selects WLAN Access Network without considering PDN-GW connectivity information, then the selection process is fast, but it leads to service disruptions for services requiring IP address preservation

Engineering Contradiction:
ImproveIP address preservationVSAvoidnetwork selection time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by pre-retrieving and storing connectivity information about PDN-GWs in the Home PLMN before the UE needs to establish a connection. This pre-fetched information is immediately available during network selection, allowing the UE to quickly identify suitable WLAN Access Networks that support IP address preservation without adding significant selection time.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent implements self-service by enabling the UE to autonomously use its own stored connectivity information and previously retrieved PDN-GW details to make network selection decisions. The UE leverages its own history and cached data to independently determine the best network without requiring external intervention or complex real-time queries, thus maintaining speed while ensuring IP address preservation.

Inventive Principle:
Principle #25Self-service

3Reliability

If UE is configured with indicators for HPLMN PDN-GW access requirements, then service continuity is ensured, but the configuration complexity increases

Engineering Contradiction:
Improveservice continuityVSAvoidUE configuration complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent implements self-service by enabling the UE to autonomously determine and configure its own network selection criteria based on stored connectivity information and service requirements. The UE automatically identifies when HPLMN PDN-GW access is needed and configures appropriate indicators without requiring manual network operator configuration, thus ensuring service continuity while minimizing configuration complexity through automation.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent applies parameter changes by dynamically adjusting the UE's network selection parameters based on stored connectivity information and service requirements. The UE modifies its selection criteria by changing parameters such as priority weights and connectivity thresholds according to the specific service needs and available network conditions, ensuring reliable service continuity through adaptive parameter adjustment rather than complex static configuration.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2804426B1WLAN access network selection by an user equipment for access to a mobile network
Publication Date: 2021.04.28 ALCATEL LUCENT SA
  • EP2804426B1 patent drawingFigure 1~2
  • EP2804426B1 patent drawingFigure 3~4

AI summary

Embodiments of the present invention include a method for WLAN Access Network WLAN-AN selection by an User Equipment UE for access to a mobile network PLMN, said selection including, for an UE roaming in a Visited PLMN VPLMN and requiring a Packet Data Network Gateway PDN-GW in its Home PLMN HPLMN, selection of a WLAN-AN having connectivity to at least one PDN-GW in said HPLMN, based on information on connectivity to at least one PDN-GW in said HPLMN of WLAN-ANs candidate for said selection, referred to as connectivity information.