Video over LTE (ViLTE) is new step in VoLTE, Voice over LTE.
It has started to enter testing phase in some markets.
To offer voice and video over an LTE-standard network, operators must migrate from circuit-switched voice to packet voice. This requires an architectural vision that supports voice and short message service (SMS) using the existing third-generation (3G) network, while providing a clear path to networks based on Session Initiation Protocol (SIP). This architecture enables newer services, such as optimized conversational video, presence, and instant messaging.
The move to 4G LTE comes at a time when mobile data traffic volumes are growing so fast that they threaten to overwhelm network resources. The mobile operator is therefore challenged with delivering mobile broadband services, lowering costs and latency, while being able to flexibly introduce new services. The all-IP network architecture of LTE provides the intelligence to do all this and more.
Previous cellular telecommunications standards, such as Global System for Mobile Communications (GSM), have had dedicated channels for circuit-switched telephony. With LTE, however, instead of a circuit-based network there is an all-IP, end-to-end connection from mobile handsets or other devices to the core network and back. A voice and video service can use the low latency and quality of service (QoS) features defined within LTE and made available on EPC and IP Radio Access Network (IP RAN) solutions.
The mobile industry has been debating the best way to provide continuity for traditional circuit-switched services while the network migrates to LTE, and has now reached consensus around a long-term strategy based on IMS, including CSFB for operators that choose to allow roaming from non-IMS subscribers or to delay their V 2oLTE and IMS deployments.
Circuit Switched Fallback (CSFB)
V²oLTE deployments and trials are occurring at an accelerated pace. In addition, some mobile operators have chosen to deploy 4G networks alongside their existing second-generation (2G) and 3G assets using CSFB until they are ready to deploy IMS.