UE Emergency Call Network Switching via Access Network Selection

The UE performs preliminary actions by attempting connection to the first access network before finalizing the emergency call setup. When the connection is rejected, the UE has already prepared alternative access networks in priority order, enabling rapid switching without delay. This preliminary attempt and preparation of alternatives resolves the contradiction by ensuring reliability through pre-planned fallback options while minimizing time loss through pre-ordered network priorities.

The UE implements a dynamic network switching mechanism where the priority order of access networks can be adjusted based on connection outcomes. When the first attempted network rejects the emergency call, the UE dynamically switches to the next priority network. This dynamic adaptation ensures optimal call quality by selecting the most suitable network while managing complexity through automated priority-based switching rather than complex manual configuration.

The UE performs preliminary actions by pre-establishing a priority order of access networks before attempting connections. This preliminary ranking enables the UE to systematically attempt networks in order of priority, ensuring the optimal network is found efficiently. The pre-planned priority structure resolves the contradiction by guaranteeing connection success through multiple attempts while minimizing time loss through organized, sequential progression rather than random or simultaneous attempts.