BlackBerry Limited
Preserving Emergency Call During Failure to Transfer

Abstract:

A system and method in a user equipment (UE) for transferring an emergency session from a first network to a second network. The method includes transmitting a first registration request message to the second network; receiving a registration reject message from the second network; detecting the emergency session between the UE and the first network is ongoing; transmitting a second registration request message comprising an emergency registration request to the second network; and receiving a registration accept message for the emergency session.