is used for MBMS. SFN (Single Frequency Network) is a broadcast network where several transmitters simultaneously send the same signal over the same frequency channel. For MBSFN following definitions are valid and these are also depicted in Figure 3.33 [14]: MBSFN Synchronization Area is an area of the network where all eNodeBs can be synchronized and perform MBSFN transmissions. MBSFN Synchronization Areas are capable of supporting one or more MBSFN Areas. On a given frequency layer, a eNodeB can only belong to one MBSFN Synchronization Area. MBSFN Synchronization Areas are independent from the definition of MBMS Service Areas: 3GPP Evolved Packet System (EPS) MBMS Service Area MBSFN Area MBSFN Area MBSFN Area MBSFN Area MBSFN Area Transmitting MBSFN Area Transmitting-Only Cell and Advertising Cell Transmitting-Only Cell MBSFN Area Reserved Cell MBMS Service Area MBSFN Area MBSFN Area MBSFN Area MBSFN Area Reserved Cell Figure 3.33 MBSFN definitions. Reproduced with permission from C 2009 3GPP2 [14] MBSFN Transmission or a transmission in MBSFN mode is a simulcast transmission technique realized by transmission of identical waveforms at the same time from multiple cells. An MBSFN Transmission from multiple cells within the MBSFN Area is seen as a single transmission by a UE. MBSFN Area consists of a group of cells within an MBSFN Synchronization Area of a network, which are coordinated to achieve an MBSFN Transmission. Except for the MBSFN Area Reserved Cells, all cells within an MBSFN Area contribute to the MBSFN Transmission and advertise its availability. A cell within an MBSFN Synchronization Area belongs to only one MBSFN Area for all MBMS services. MBSFN Area Reserved Cell is a cell within a MBSFN Area which does not contribute to the MBSFN Transmission. The cell may be allowed to transmit for other services but at restricted power on the resource allocated for the MBSFN transmission. The overall user plane architecture for MBSFN content synchronization is shown in Figure 3.34. A SYNC protocol between the 