Patent ID: 8724586

Claim:
A method implemented by a Mobile Management Entity (MME) for determining if a handoff request for an active voice session of a user equipment (UE) is applicable to a Single Radio Voice Call Continuity (SRVCC) procedure or a Circuit Switched over Long-Term Evolution via Generic Access Network (CSoLTEvGAN) procedure, the method comprising the steps of: wherein the UE, is moving from an Evolved-UMTS Radio Access Network (E-UTRAN) to a GSM Radio Access Network/UMTS Radio Access Network (GERAN/UTRAN); receiving an indication where the UE is SRVCC capable and CSoLTEvGAN capable; determining if an CSoLTE indicator is received in addition to receiving the indication where the UE is SRVCC capable and CSoLTEvGAN capable; in response to determining CSoLTE indicator has been received in addition to receiving the indication where the UE is SRVCC capable and CSoLTEvGAN capable, directing handoff signaling for the active voice session of the UE over a Sv interface to a Generic Access Network Controller (GANC) in accordance with the CSoLTEvGAN procedure; and in response to determining the CSoLTE indicator has not been received in addition to receiving the indication where the UE is SRVCC capable and CSoLTEvGAN capable, directing the handoff signaling for the active voice session of the UE over a Sv interface to a Mobile Switching Centre (MSC) in accordance with a Single Radio Voice Call Continuity (SRVCC) procedure; directing the handoff signaling for the active voice session of the UE to a service GPRS support node (SGSN) when failing to receive both the indication where the UE is SRVCC capable and CSoLTEvGAN capable and the CSoLTE indicator.