Data transmission method and data transmission apparatus

A transmission apparatus, comprising:

• a receiver configured to receive, from a source access network device, data packets of a quality of service (QoS) flow and a first end marker packet over a first data tunnel, wherein the data packets are received by the source access network device from a first core network user plane device, the first end marker packet indicates an end of sending data packets of the QoS flow to the first core network user plane device, and the first data tunnel is corresponding to a first protocol data unit (PDU) session;
• and
• a transmitter configured to send the received data packets and a second end marker packet to a second core network user plane device over a second data tunnel, wherein the second end marker packet is corresponding to an evolved packet system (EPS) bearer, and the second data tunnel is corresponding to the EPS bearer.

A non-transitory computer readable medium, comprising computer readable instructions stored thereon which, when executed by a processor, cause a communication device to implement:

• receiving, from a source access network device, data packets of a quality of service (QoS) flow and a first end marker packet over a first data tunnel, wherein the data packets are received by the source access network device from a first core network user plane device, the first end marker packet indicates an end of sending data packets of the QoS flow to the first core network user plane device, and the first data tunnel is corresponding to a first protocol data unit (PDU) session and
• transmitting the received data packets and a second end marker packet to a second core network user plane device over a second data tunnel, wherein the second end marker packet is corresponding to an evolved packet system (EPS) bearer, and the second data tunnel is corresponding to the EPS bearer.