HLR Roaming Retry for Pre-Paging Failure Resolution

The patent applies preliminary action by performing pre-paging before the actual call establishment to verify user availability and location stability. The pre-paging process is initiated after routing request but before final call setup, allowing the network to prepare for potential call failures due to user mobility. This preliminary verification step helps identify users at high risk of moving during call establishment and triggers alternative handling mechanisms.

The patent implements feedback mechanisms where the HLR monitors user location changes during the call establishment process. When the HLR detects that a user has moved to a different location area during pre-paging or call setup, it provides feedback to trigger a roaming retry procedure. The HLR sends feedback signals to the VMSC/VLR to initiate retry procedures, and the system continuously monitors whether the retry is successful before completing the call establishment. This feedback loop enables dynamic adaptation to user mobility without requiring complex predetermined retry logic at every network element.

The patent applies self-service by enabling the HLR to automatically detect and respond to user location changes without requiring explicit notifications from other network elements. The HLR monitors the location updating process and autonomously determines when to trigger roaming retry based on its own records of user location history and current status. This self-service approach simplifies timing control by eliminating the need for complex coordination protocols between multiple network elements, as the HLR independently manages the retry timing based on its internal state and external observations.