o RBs is ensured by the content synchronization method, which operates in the user plane between the MBMS-GW and the eNode Bs [8,14]. It is based on adding byte counts and optionally also peri- odic time stamps to the packets sent between the MBMS-GW and eNode B as an indication of the time when the particular packet needs to be sent on the radio interface. Because the content synchronization scheme is purely a user plane proce- dure without RRM relevance and at the time of writing the exact method has not yet been selected by 3GPP, we do not address it in the rest of this chapter. For single-cell transmission mode, the eNode B can decide autonomously and in a dynamic fashion which RBs it wants to use for sending MBMS data and which for unicast data. The selection of transport format can also be dynamic, much in the same way as for unicast traffic. This means that the scheduling of MBMS data can be done as part of the regular scheduling function in the eNode B. As it has been mentioned earlier, the single cell transmission can be employed with or with- out UE feedback. The UE feedback information helps to utilize the radio resources more efficiently by adapting the transmission to the actual radio conditions of the © 2009 by Taylor & Francis Group, LLC Long Term Evolution: 3GPP LTE Radio and Cellular Technology different UEs. For example, if no feedback information is available, the transmis- sion power setting or the transport format selection has to assume the worst-case scenario: that is, that even a UE on the cell edge should be able to receive the trans- mission. However, if channel quality feedback or HARQ acknowledge/negative acknowledge (ACK/NACK) feedback is available, the transmit power or MCS can be adapted to the actual radio link conditions, and they can be less robust because unsuccessful receptions can always be compensated by a retransmission. However, it still remains true that a multicast transmission has to adapt to the channel quality conditions of the worst-case UE. Therefore, a single cell m