Multimedia Broadcast Multicast Service (MBMS)
WCDMA Release 99 and HSDPA Release 5 are used in commercial networks to deliver multimedia content such as mobile TV and streaming videos. The point-to-point data delivery in WCDMA Release 99 and HSDPA Release 5 allows full flexibility when delivering user specific and on-demand content to many users at any time. The point-to-point delivery is also spectrum efficient when the number of users is not too large. When the number of users increases and they would like to receive the same content at the same time, it is more efficient to use point-to-multipoint delivery. The 3GPP Release 6 Multimedia Broadcast Multicast Service (MBMS) specification introduces point-to-multipoint support. Cellular networks can with MBMS provide the same content efficiently to a large number of subscribers at the same time. This chapter introduces the MBMS concept, 3GPP MBMS specifications and the expected MBMS performance. The terminal capability and MBMS use cases are presented as well.
MBMS reuses the radio and core network elements in the legacy 3GPP architecture to make the introduction of MBMS cost efficient, see Figure 14.1. In addition to the legacy elements, MBMS introduces the Multimedia Broadcast and Multicast Service center (BM-SC). The new BM-SC element supports a number of functions, e.g., service scheduling, service authentication, content encryption, key management and ...