Patent ID: 8837344

Claim:
A multicast and broadcast service (MBS) data transmission synchronization apparatus of a radio access station, comprising: an information reception unit configured to receive transmission synchronization information from an access control router (ACR); an information reception loss check unit configured to determine whether the transmission synchronization information received through the information reception unit is lost; a content reception unit configured to sequentially receive a content packet from an MBS content source, the content packet comprising content time information; a packet reception loss check unit configured to determine whether the content packet received through the content reception unit is lost; a retransmission request unit configured to transmit a retransmission request message for lost transmission synchronization information or a lost content packet to the ACR in response to a request from the information reception loss check unit or the packet reception loss check unit; a transmission time determination unit configured to determine a transmission time of the received content packet on the basis of the transmission synchronization information and the content time information; and a content transmission unit configured to transmit the received content packet to a plurality of mobile terminals at the transmission time.