A method of transmitting data, applicable to a transmitting end, the method comprises: transmitting a plurality of first Real-time Transport Protocol, RTP, data packets to a receiving end over an RTP data link established previously with the receiving end; receiving a retransmission indication message sent by the receiving end, the retransmission indication message indicating an RTP data packet to be retransmitted among the plurality of first RTP data packets; and suffixing a padding unit to the RTP data packet to be retransmitted according to the retransmission indication message to obtain a second RTP data packet, wherein the second RTP data packet comprises an RTP padding field that indicates that the second RTP data packet is a retransmitted RTP data packet, a type flag of the second RTP data packet is same as a type flag of the first RTP data packet, and an RTP padding field in the second RTP data packet comprises the padding unit, wherein the padding unit comprises a retransmission indication byte and a length indication byte, and the retransmission indication byte at least comprises a retransmission flag, a count flag and a data flag, wherein the retransmission flag indicates that the second RTP data packet is the retransmitted RTP data packet, the count flag indicates the number of times that the transmitting end transmits the second RTP data packet, the data flag indicates whether an RTP data field in the second RTP data packet is an RTP data field in the RTP data packet to be retransmitted, and the length indication byte indicates a length of the RTP padding field in the second RTP data packet; the method further comprises: transmitting the second RTP data packet to the receiving end over the RTP data link, wherein the second RTP data packet and the first data packets are transmitted over the same RTP data link. transmitting a plurality of first Real-time Transport Protocol, RTP, data packets to a receiving end over an RTP data link established previously with the receiving end; receiving a retransmission indication message sent by the receiving end, the retransmission indication message indicating an RTP data packet to be retransmitted among the plurality of first RTP data packets; and suffixing a padding unit to the RTP data packet to be retransmitted according to the retransmission indication message to obtain a second RTP data packet, wherein the second RTP data packet comprises an RTP padding field that indicates that the second RTP data packet is a retransmitted RTP data packet, a type flag of the second RTP data packet is same as a type flag of the first RTP data packet, and an RTP padding field in the second RTP data packet comprises the padding unit, wherein the padding unit comprises a retransmission indication byte and a length indication byte, and the retransmission indication byte at least comprises a retransmission flag, a count flag and a data flag, wherein the retransmission flag indicates that the second RTP data packet is the retransmitted RTP data packet, the count flag indicates the number of times that the transmitting end transmits the second RTP data packet, the data flag indicates whether an RTP data field in the second RTP data packet is an RTP data field in the RTP data packet to be retransmitted, and the length indication byte indicates a length of the RTP padding field in the second RTP data packet; the method further comprises: transmitting the second RTP data packet to the receiving end over the RTP data link, wherein the second RTP data packet and the first data packets are transmitted over the same RTP data link.