Data transmission method and apparatus

1. A data transmission method, applied to a first communications device or a chip in the first communications device, wherein the first communications device is a donor base station or a distributed unit (DU) of the donor base station, and wherein the data transmission method comprises:

obtaining first data; and

after obtaining the first data;

compressing sub-information in the first data based on a first preset compression algorithm, wherein the sub-information comprises at least one of an internet protocol (IP) header, a stream control transmission protocol (SCTP) common header, and information other than target information in an SCTP data chunk, and the target information is at least one of user data, an SCTP stream identifier, and an SCTP payload protocol identifier (PPI); or wherein the sub-information comprises at least one of an IP header, a user datagram protocol (UDP) header, and information other than a tunnel endpoint identifier (TEID) in a general packet radio service tunneling protocol (GTP) header; and

sending a first message to a second communications device, wherein the first message comprises the first data obtained after compression and a type identifier, wherein the type identifier is used to indicate a type of the first data, and wherein the type of the first data comprises at least one of user plane data, a status report, a control plane message, and a radio resource control (RRC) message of a terminal; and

wherein the second communications device is a next-hop device of the first communications device; and

if the first data is the user plane data, the first message comprises first indication information and a global sequence number (SN) of the user plane data, and the first indication information is used to indicate a data radio bearer (DRB) of the terminal to which the user plane data belongs;

if the first data is the status report, the first data comprises the global SN of the user plane data carried over the DRB of the terminal, wherein the first data is used to indicate a transmission status of a DRB data packet of a third communications device, and wherein the third communications device is the terminal, an intermediate forwarding node, or a serving node of the terminal; or

if the first data is the control plane message, the first message comprises at least one of transport layer protocol layer information of a first interface, second indication information, an identifier of the terminal on the first interface, and third indication information, wherein the first interface is a logical communications interface between the first communications device and the second communications device, wherein the transport layer protocol layer information of the first interface comprises at least one of an IP address of the first communications device, an IP address of the second communications device, an IP address of the donor base station or the DU, a port number of the first communications device, a port number of the second communications device, a port number of the donor base station or the DU, the SCTP stream identifier, and the PPI, wherein the second indication information is used to indicate the first communications device, and wherein the third indication information is used to indicate the first interface; or the first message comprises fourth indication information and an identifier of the serving node of the terminal, and the fourth indication information is used to indicate the terminal.

2. The data transmission method according to claim 1 , wherein if the first data is the status report, the first data further comprises fifth indication information, and the fifth indication information is used to indicate the DRB of the terminal.

3. The data transmission method according to claim 2 , wherein if the third communications device is the intermediate forwarding node or the serving node of the terminal, the first data comprises the fifth indication information carried over each DRB in at least one DRB of the third communications device.

4. The data transmission method according to claim 1 , wherein the first message further comprises at least one of a target identifier and sixth indication information, wherein the target identifier is used to indicate the serving node of the terminal, and wherein the sixth indication information is used to indicate the terminal.

5. The data transmission method according to claim 1 , wherein if the first data is the control plane message, and when the first message comprises the identifier of the terminal on the first interface or the fourth indication information, the obtaining first data comprises:

receiving a second message comprising second data, wherein the second data comprises seventh indication information, and wherein the seventh indication information is used to indicate the terminal or the DRB of the terminal;

obtaining the second data; and

replacing the seventh indication information with the identifier of the terminal on the first interface or the fourth indication information to generate the first data.

6. The data transmission method according to claim 1 , wherein the first communications device is the DU, and wherein the data transmission method further comprises:

receiving a fifth message sent by the second communications device, wherein the fifth message comprises fourth data; and

decompressing the fourth data based on a fourth preset compression algorithm, and sending the decompressed fourth data to a centralized unit (CU) of the donor base station.

7. The data transmission method according to claim 6 , wherein the first communications device is the DU, and wherein the obtaining first data comprises:

receiving a sixth message sent by the CU, wherein the sixth message comprises fifth data;

obtaining the fifth data from the sixth message; and

decompressing the fifth data based on a fifth preset compression algorithm to obtain the first data.

8. The data transmission method according to claim 1 , wherein after the obtaining first data, the data transmission method further comprises:

processing the first data based on a first preset key and a first preset target algorithm, wherein the first preset target algorithm comprises at least one of a preset encryption algorithm and a first preset integrity protection algorithm; and

wherein the sending a first message to a second communications device comprises:

sending the first message comprising the processed first data to the second communications device.

9. The data transmission method according to claim 8 , wherein the first communications device is the DU, and wherein the data transmission method further comprises:

receiving a ninth message sent by the second communications device, wherein the ninth message comprises eighth data;

obtaining the eighth data, and processing the eighth data based on a fourth preset key and a fourth preset target algorithm; and

sending the processed eighth data to a centralized unit (CU) of the donor base station, wherein the fourth preset target algorithm comprises at least one of a third preset decryption algorithm and a fourth preset integrity protection algorithm.

10. The data transmission method according to claim 1 , wherein after obtaining the first data comprises in response to obtaining the first data.

11. A data transmission apparatus, wherein the data transmission apparatus is a first communications device or a chip in the first communications device, wherein the first communications device is a donor base station or a distributed unit (DU) of the donor base station, and wherein the data transmission apparatus comprises: at least one processor and a memory having instructions, wherein the instructions are executed by the at least one processor to cause the apparatus to:

obtain first data; and

after obtaining the first data;

compress sub-information in the first data based on a first preset compression algorithm, wherein the sub-information comprises at least one of an internet protocol (IP) header, a stream control transmission protocol (SCTP) common header, and information other than target information in an SCTP data chunk, and the target information is at least one of user data, an SCTP stream identifier, and an SCTP payload protocol identifier (PPI); or wherein the sub-information comprises at least one of an IP header, a user datagram protocol (UDP) header, and information other than a tunnel endpoint identifier (TEID) in a general packet radio service tunneling protocol (GTP) header; and

send a first message to a second communications device, wherein the first message comprises the first data obtained after compression and a type identifier, wherein the type identifier is used to indicate a type of the first data, and wherein the type of the first data comprises at least one of user plane data, a status report, a control plane message, and a radio resource control (RRC) message of a terminal; and wherein the second communications device is a next-hop device of the first communications device; and

if the first data is the user plane data, the first message comprises first indication information and a global sequence number (SN) of the user plane data, and the first indication information is used to indicate a data radio bearer (DRB) of the terminal to which the user plane data belongs;

if the first data is the status report, the first data comprises the global SN of the user plane data carried over the DRB of the terminal, wherein the first data is used to indicate a transmission status of a DRB data packet of a third communications device, and wherein the third communications device is the terminal, an intermediate forwarding node, or a serving node of the terminal; or

if the first data is the control plane message, the first message comprises at least one of transport layer protocol layer information of a first interface, second indication information, an identifier of the terminal on the first interface, and third indication information, wherein the first interface is a logical communications interface between the first communications device and the second communications device, wherein the transport layer protocol layer information of the first interface comprises at least one of an IP address of the first communications device, an IP address of the second communications device, an IP address of the donor base station or the DU, a port number of the first communications device, a port number of the second communications device, a port number of the donor base station or the DU, the SCTP stream identifier, and the PPI, wherein the second indication information is used to indicate the first communications device, and wherein the third indication information is used to indicate the first interface; or the first message comprises fourth indication information and an identifier of the serving node of the terminal, and the fourth indication information is used to indicate the terminal.

12. The data transmission apparatus according to claim 11 , wherein if the first data is the status report, the first data further comprises fifth indication information, and the fifth indication information is used to indicate the DRB of the terminal.

13. The data transmission apparatus according to claim 12 , wherein if the third communications device is an intermediate forwarding node or a serving node of the terminal, the first data comprises the fifth indication information carried over each DRB in at least one DRB of the third communications device.

14. The data transmission apparatus according to claim 11 , wherein the first message further comprises at least one of a target identifier and sixth indication information, wherein the target identifier is used to indicate the serving node of the terminal, and wherein the sixth indication information is used to indicate the terminal.

15. The data transmission apparatus according to claim 11 , wherein if the first data is the control plane message, and the first message comprises the identifier of the terminal on the first interface or the fourth indication information, the instructions further cause the apparatus to:

receive a second message comprising second data, wherein the second data comprises seventh indication information, and wherein the seventh indication information is used to indicate the terminal or the DRB of the terminal;

obtain the second data from the second message; and

replace the seventh indication information with the identifier of the terminal on the first interface or the fourth indication information to generate the first data.

16. The data transmission apparatus according to claim 11 , wherein the first communications device is the DU, and wherein the instructions further cause the apparatus to:

receive a fifth message sent by the second communications device, wherein the fifth message comprises fourth data; and

decompress the fourth data based on a fourth preset compression algorithm; and send the decompressed fourth data to a centralized unit (CU) of the donor base station.

17. The data transmission apparatus according to claim 16 , wherein the first communications device is the DU, and wherein the instructions further cause the apparatus to:

receive a sixth message sent by the CU, wherein the sixth message comprises fifth data;

obtain the fifth data from the sixth message; and

decompress the fifth data based on a fifth preset compression algorithm, to obtain the first data.

18. The data transmission apparatus according to claim 11 , wherein the instructions further cause the apparatus to:

process, after obtaining the first data, the first data based on a first preset key and a first preset target algorithm, wherein the first preset target algorithm comprises at least one of a preset encryption algorithm and a first preset integrity protection algorithm; and

send the first message comprising the processed first data to the second communications device.

19. The data transmission apparatus according to claim 18 , wherein the first communications device is the DU, and wherein the instructions further cause the apparatus to:

receive a ninth message sent by the second communications device, wherein the ninth message comprises eighth data;

obtain the eighth data from the ninth message;

process the eighth data based on a fourth preset key and a fourth preset target algorithm; and

send the processed eighth data to a centralized unit (CU) of the donor base station, wherein the fourth preset target algorithm comprises at least one of a third preset decryption algorithm and a fourth preset integrity protection algorithm.

20. The data transmission apparatus according to claim 11 , wherein after obtaining the first data comprises in response to obtaining the first data.