Patent ID: 8830877

Claim:
A transmitting device for a multicast and broadcast service, the transmitting device comprising: an encoder configured to receive data to generate parity; an ARQ block generator configured to generate first automatic repeat request (ARQ) blocks by dividing the data, and generate second ARQ blocks by dividing the parity; a PDU generator configured to generate a first protocol data unit (PDU) comprising a specified number of the first ARQ blocks and a second protocol unit (PDU) comprising a specified number of the second ARQ blocks; and a transmitter configured to: transmit the first PDUs to a plurality of terminals; receive a non-acknowledgement response from at least one terminal after transmitting the first PDU, the non-acknowledgement response indicating the number of lost first ARQ blocks; determine whether or not the second ARQ blocks are exhausted; when the second ARQ blocks are remaining, transmit the second PDU in accordance with the non-acknowledge response; and when the second ARQ blocks are exhausted, directly transmit the lost first ARQ blocks to the at least one terminal that transmitted the non-acknowledgement response.