ePDG Reselection via Metric Evaluation for Untrusted Network Reliability

The patent implements dynamic ePDG reselection by enabling UE to evaluate reselection metrics and automatically switch between ePDGs based on current network conditions. The UE monitors connection status, PLMN changes, and operational parameters, then dynamically selects alternative ePDGs from a configured list when the current ePDG becomes unavailable or suboptimal, thereby resolving the contradiction between connection reliability and reselection adaptability.

The patent applies preliminary action by pre-configuring the UE with a list of alternative ePDGs before connection failures occur. When the current ePDG becomes unavailable, the UE can immediately select from the pre-configured alternatives without delay, improving connection reliability while maintaining the ability to adapt to changing network conditions.

The patent implements self-service by enabling the UE to autonomously perform ePDG reselection based on locally evaluated metrics without requiring complex network-side control or additional signaling infrastructure. The UE independently monitors connection status, evaluates reselection criteria, and executes switching decisions, thereby maintaining service continuity while minimizing additional signaling overhead and system complexity.

The patent applies feedback by implementing metric evaluation mechanisms that continuously monitor connection quality, PLMN status, and operational parameters. This feedback-driven approach enables the UE to make informed reselection decisions based on actual network conditions, improving service continuity while keeping the reselection mechanism efficient and manageable through condition-based triggering rather than continuous complex processing.

The patent implements periodic action by evaluating ePDG reselection metrics at specific intervals or upon triggering events such as connection failures, PLMN changes, or inactivity periods, rather than continuously monitoring all parameters. This approach maintains sufficient reselection accuracy by checking metrics at meaningful moments while significantly reducing energy consumption compared to continuous monitoring.

The patent applies parameter changes by adjusting the monitoring and evaluation frequency based on operational context. The UE can transition between different monitoring intensities - performing detailed metric evaluations when connection issues are detected versus using lighter-weight checks during stable operation - thereby maintaining reselection accuracy when needed while minimizing energy consumption during normal operation.