The MBMS feature is split into the MBMS Bearer Service and the MBMS User Service and has been defined to be offered over both
UTRAN (i.e.
WCDMA, TD-CDMA and TD-SCDMA) and
LTE (where it is often referred to as eMBMS). The MBMS Bearer Service includes a Unicast and a Broadcast Mode. MBMS Operation On-Demand (MOOD) allows dynamic switching between Unicast and Broadcast over LTE, based on configured triggers. The MBMS Bearer Service uses IP multicast addresses for the IP flows. The advantage of the MBMS Bearer Service compared to unicast bearer services (interactive, streaming, etc.) is that the transmission resources in the
core and
radio networks are shared. One MBMS packet flow is replicated by
GGSN, SGSN and RNCs. MBMS may use an advanced counting scheme to decide, whether or not zero, one or more dedicated (i.e. unicast) radio channels lead to a more efficient system usage than one common (i.e. broadcast) radio channel. • UTRAN MBMS offers up to 256 kbit/s per MBMS Bearer Service and between 800 kbit/s and 1.7 Mbit/s per cell/band. The actual cell capacity depends on the
UE capabilities. • GERAN MBMS offers between 32 kbit/s and 128 kbit/s. Up to 4 GSM timeslots may be used for one MBMS bearer in the downlink direction. The actual data rate per Traffic Slot depends on network dimensioning. The MBMS User Service is basically the MBMS Service Layer and offers two different data Delivery Methods: • The
Streaming Delivery Method can be used for continuous transmissions like mobile television services. An application layer
FEC code may be used to increase the transmission reliability. • The
Download Delivery Method is intended for “download and play” services. A
File Repair service may be offered to compensate for unreliable delivery. MBMS has been standardized in various groups of
3GPP (Third Generation Partnership Project), and the first phase standards are found in
UMTS release 6. As Release 6 was functionally frozen by the 3rd quarter of 2004, practical network implementations may be expected by the end of 2007, and the first functional mobile terminals supporting MBMS are estimated to be available by also end of 2007. eMBMS has been standardized in various groups of 3GPP as part of LTE release 9. The
LTE version of MBMS, referred to as
Multicast-broadcast single-frequency network (MBSFN), supports broadcast only services and is based on a Single Frequency Network (SFN) based
OFDM waveform and so is functional similar to other broadcast solutions such as DVB-H, -SH and -NGH. In Release 14, the
3GPP enhanced the specifications for eMBMS with a view to making the technology more attractive for deployment by operators and broadcasters. The 3GPP's work on the next generation of technology in Release 16 includes a study on LTE-based broadcast on
5G networks, MBMS APIs for mission-critical services and MBMS user services for IoT. == 3GPP technical specifications ==