The joint solution simplifies complex IMS architecture, reduces VoLTE deployment cost and time to market and enables mobile operators to deliver quality voice services for networks of any size, private or public. The migration to VoLTE is complex and challenging and operators need an architecture that is both flexible and capable in order to deploy IMS core while preserving service quality and reliability.i 1 2 This requires an architectural vision that supports voice using the existing network and provides a clear path to 5G voice.