Patent ID: 8768351

Claim:
A method for implementing a circuit-switched (CS) call delivery comprising: receiving a mobile terminating call for user equipment (UE) at a home location register (HLR); determining, at the HLR, a first mobile switching center (MSC) to perform a first call termination attempt for the mobile terminating call based on location data by sending a provide roaming number (PRN) request with a pre-paging supported parameter to the first MSC, wherein the first call termination attempt includes instructing the UE to return to a CS network domain to receive the mobile terminating call; receiving, at the HLR, a message from the first MSC indicating that the UE is not connected to the first MSC; determining, at the HLR, whether a registration of the UE is in process at a second MSC within a duration of time in response to reception of the message from the first MSC; and determining, at the HLR, whether the registration of the UE is successful, wherein, if the registration succeeds, a second call termination attempt for the mobile terminating call is made via the second MSC.