Network Node Mobility Management for Failed PLMN Roaming
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
When a failure occurs in a second Public Land Mobile Network (PLMN), existing systems lack a method to efficiently manage mobility and provide communication services to subscribers of the affected PLMN, leading to disruptions in mobile communication services.
Innovation Solution
A network node in a first PLMN manages mobility by receiving access requests from terminals subscribed to the second PLMN, determining whether to allow roaming based on the failure, and transmitting response messages that notify the terminal of the failure, allowing for controlled access and service provision through S-roaming mode settings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing systems are used to manage mobility when a failure occurs in a second PLMN, then network operations continue normally, but communication services are disrupted for subscribers of the affected PLMN
Solution Approach 1:
The network node dynamically adjusts its behavior based on the failure status of the second PLMN. When failure is detected, the system transitions from normal operation mode to failure handling mode, enabling special roaming arrangements for affected subscribers while maintaining normal operations for other subscribers, thus resolving the contradiction between service availability and operational normality
Solution Approach 2:
The network node in the first PLMN acts as an intermediary for subscribers of the failed second PLMN. It receives access requests from these subscribers, determines whether to allow access based on failure status, and manages their mobility independently, thereby maintaining communication services despite the failure in the home network
2Reliability
If access requests from terminals of the failed PLMN are allowed without control, then communication services are restored, but signaling waste increases
Solution Approach 1:
The network node performs preliminary determination of whether to allow access before actually processing the full access request. By checking the failure status and making a preliminary decision, the system avoids unnecessary signaling exchanges for requests that would be rejected, thus reducing signaling waste while maintaining service continuity for eligible subscribers
Solution Approach 2:
The system implements feedback mechanisms where the network node monitors access requests, determines their validity based on failure status, and provides appropriate responses. This feedback loop enables intelligent filtering of access requests, allowing legitimate services while blocking or optimizing invalid requests, thereby reducing signaling waste
3Device complexity
If roaming is not allowed during network failure, then network resources are protected, but user experience deteriorates
Solution Approach 1:
The network node applies different quality settings to different subscribers based on their home network status. Subscribers from the failed second PLMN receive special treatment with roaming enabled, while other subscribers continue with normal roaming policies. This localized differentiation resolves the contradiction by providing enhanced service quality to affected users without compromising overall network resource management
Solution Approach 2:
The system changes the roaming parameter status dynamically based on network failure conditions. When failure is detected, the roaming permission parameter is changed from restricted to allowed for affected subscribers, enabling them to access services in the first PLMN. This parameter change approach maintains simple resource management while dramatically improving user experience for affected subscribers
Data Source
AI summary
A disclosure of the present specification provides a method performed by a network node that manages mobility in a first public land mobile network (PLMN). The network node may receive an access request message of a terminal from a base station in the first PLMN. The terminal may be a terminal having joined a second PLMN. On the basis of occurrence of a failure in the second PLMN, the network node may determine whether to allow the terminal to roam to the first PLMN.