Method, apparatus, and system for implementing data transmission

1. A method for implementing data transmission, wherein the method comprises:

obtaining, by a sending device, a data packet in a target data flow; and

sending, by the sending device, the data packet through each of at least two physical links between the sending device and a receiving device, wherein the data packet sent through each of the at least two physical links comprises a same sequence number, wherein the sequence number of the data packet is carried in an extended shim layer header of the data packet between a data link layer header and a network layer header and the extended shim layer header corresponds to a shim layer protocol.

2. The method according to claim 1 , wherein before the sending, by the sending device, the data packet through each of at least two physical links between the sending device and a receiving device, the method further comprises: adding, by the sending device, the sequence number to the data packet.

3. The method according to claim 1 , wherein the data packet further carries a flow identifier of the target data flow.

4. The method according to claim 1 , wherein the target data flow comprises one or more data flows of a preset service.

5. The method according to claim 1 , wherein a 5-tuple of the target data flow is a preset 5-tuple.

6. A communications device, wherein the communications device comprises:

a non-transitory memory storing instructions; and

a processor coupled to the non-transitory memory; wherein the instructions, when executed by the processor, cause the communications device to be configured to:

obtain a data packet in a target data flow; and

send the data packet through each of at least two physical links between the communications device and a receiving device, wherein the data packet sent through each of the at least two physical links comprises a same sequence number, wherein the sequence number of the data packet is carried in an extended shim layer header of the data packet between a data link layer header and a network layer header and the extended shim layer header corresponds to a shim layer protocol.

7. The communications device according to claim 6 , wherein the instructions, when executed by the processor, further cause the communications device to be configured to add the sequence number to the data packet.

8. The communications device according to claim 6 , wherein the data packet further comprises a flow identifier of the target data flow.

9. The communications device according to claim 6 , wherein the target data flow comprises one or more data flows of a preset service.

10. The communications device according to claim 6 , wherein a 5-tuple of the target data flow is a preset 5-tuple.

11. A communications device, wherein the communications device comprises:

a non-transitory memory storing instructions; and

a processor coupled to the non-transitory memory; wherein the instructions, when executed by the processor, cause the communications device to be configured to:

receive data packets in a target data flow through each of at least two physical links between the communications device and a sending device, wherein each data packet in the target data flow received through each of the at least two physical links carries a sequence number; and

for a data packet that is sent by the sending device through each of the at least two physical links and that comprises a same sequence number in the target data flow, combine, into the target data flow, the data packet that is first received and that carries the sequence number, wherein the sequence number of each data packet in the target data flow is carried in an extended shim layer header of the data packet between a data link layer header and a network layer header and the extended shim layer header corresponds to a shim layer protocol.

12. The communications device according to claim 11 , wherein the instructions, when executed by the processor, further cause the communications device to be configured to: for the data packet that is sent by the sending device through each of the at least two physical links and that comprises the same sequence number in the target data flow, discard the data packet that is received later and that carries the sequence number.

13. The communications device according to claim 11 , wherein each data packet in the target data flow that is sent by the sending device through each of the at least two physical links further comprises a flow identifier of the target data flow; and the instructions, when executed by the processor, further cause the communications device to be configured to identify a data packet that carries the flow identifier of the target data flow in the received data packets, as the data packet in the target data flow.

14. The method according to claim 1 , wherein the data packet further comprises a control message used to control a process of sending the target data flow and the control message is one of: start notification, end notification, or acknowledgment message.

15. The method according to claim 1 , wherein the data packet further comprises a flow status, wherein the flow status indicates single-link or multi-link, wherein multi-link comprises indications for multi-sending and selective receiving manner, or load balancing manner.

16. The method according to claim 1 , further comprising:

obtaining, by the sending device, data packets of an other preset service;

determining that the other preset service corresponds to a load balancing manner; and

sending, by the sending device, the data packets corresponding to the other preset service through each of at least two physical links between the sending device and the receiving device, wherein the data packets sent through each of the at least two physical links comprise different sequence numbers.