Japanese number two operator KDDI will offer voice services via Circuit Switched Fallback (CSFB) technology from vendor Nokia Siemens Networks (NSN) when it launches LTE data services towards the end of next year. NSN claims the deployment will allow KDDI to use its existing CDMA network to continue delivering high-quality voice services while maximising the efficiency of its newly deployed LTE network. A longer-term solution to the challenge of providing voice services over all-IP LTE networks is expected to be provided by the use of Voice over LTE (VoLTE) technology.