Data transmission method, communications apparatus, and user plane function entity

1. A data transmission method, comprising:

obtaining, by a communications apparatus, a correspondence between a quality of service flow identifier of a service flow and an inter-packet time interval of the service flow, wherein the correspondence indicates a corresponding relationship between the quality of service flow identifier and the inter-packet time interval;

establishing, by the communications apparatus based on the correspondence, a gate queue used to send a particular data packet;

establishing a mapping relationship between the gate queue and the quality of service flow identifier;

receiving, by the communications apparatus, a data packet from an upper-level sending device of a transmission link; and

if the data packet comprises the quality of service flow identifier, periodically scheduling, by the communications apparatus, the data packet based on the gate queue to which the quality of service flow identifier is mapped.

2. The method according to claim 1 , wherein the communications apparatus is a user plane function entity, the upper-level sending device is a base station, and the data packet is an uplink data packet, and wherein obtaining, by the communications apparatus, the correspondence between the quality of service flow identifier of the service flow and the inter- packet time interval of the service flow comprises:

receiving, by the communications apparatus, the correspondence from a session management function entity.

3. The method according to claim 1 , wherein the communications apparatus is a base station, the upper-level sending device is a user plane function entity, and the data packet is a downlink data packet.

4. The method according to claim 3 , wherein if base station handover is to be performed and the base station is a source base station during the base station handover, the obtaining, by the communications apparatus, the correspondence between the quality of service flow identifier of the service flow and the inter-packet time interval of the service flow comprises:

receiving, by the source base station, the correspondence from an access and mobility management function entity, and wherein the method further comprises:

sending, by the source base station, the correspondence to a target base station.

5. The method according to claim 3 , wherein if base station handover is to be performed and the base station is a target base station during the base station handover, obtaining, by the communications apparatus, the correspondence between the quality of service flow identifier of the service flow and the inter-packet time interval of the service flow comprises:

receiving, by the target base station, the correspondence from a source base station.

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

obtaining, by a session management function entity, subscription information of a terminal device from a unified data management entity, wherein the subscription information comprises the inter-packet time interval of the service flow;

allocating, by the session management function entity, the quality of service flow identifier to the service flow;

establishing the correspondence between the quality of service flow identifier and the inter-packet time interval; and

sending, by the session management function entity, the correspondence to the communications apparatus, wherein the correspondence is used to periodically schedule the data packet.

7. The method according to claim 6 , wherein the communications apparatus is a base station, and wherein sending, by the session management function entity, the correspondence to the communications apparatus comprises:

sending, by the session management function entity, the correspondence to the base station through an access and mobility management function entity.

8. The method according to claim 6 , wherein the communications apparatus is a user plane function entity.

9. The method according to claim 8 , wherein the user plane function entity is a target user plane function entity, and before sending, by the session management function entity, the correspondence to the communications apparatus, the method further comprises:

receiving, by the session management function entity from an access and mobility management function entity, a request for reselecting a user plane function entity; and

selecting, by the session management function entity, the target user plane function entity, wherein sending, by the session management function entity, the correspondence to the communications apparatus comprises:

sending, by the session management function entity, the correspondence to the target user plane function entity.

10. A communications apparatus, comprising:

at least one processor;

a non-transitory computer-readable storage medium coupled to the at least one processor and storing programming instructions for execution by the at least one processor, wherein the programming instructions instruct the at least one processor to:

obtain a correspondence between a quality of service flow identifier of a service flow and an inter-packet time interval of the service flow, wherein the correspondence indicates a corresponding relationship between the quality of service flow identifier and the inter-packet time interval;

establish, based on the correspondence, a gate queue used to send a particular data packet;

establish a mapping relationship between the gate queue and the quality of service flow identifier;

receive a data packet from an upper-level sending device of a transmission link; and

if the data packet comprises the quality of service flow identifier, periodically schedule the data packet based on the gate queue to which the quality of service flow identifier is mapped.

11. The communications apparatus according to claim 10 , wherein the communications apparatus is a user plane function entity, the upper-level sending device is a base station, and the data packet is an uplink data packet, and wherein the programming instructions further instruct the at least one processor to:

receive the correspondence from a session management function entity.

12. The communications apparatus according to claim 10 , wherein the communications apparatus is a base station, the upper-level sending device is a user plane function entity, and the data packet is a downlink data packet.

13. The communications apparatus according to claim 12 , wherein if base station handover is to be performed and the base station is a source base station during the base station handover, the programming instructions further instruct the at least one processor to:

receive the correspondence from an access and mobility management function entity; and

send the correspondence to a target base station.

14. The communications apparatus according to claim 12 , wherein if base station handover needs to be performed and the base station is a target base station during the base station handover, the programming instructions further instruct the at least one processor to receive the correspondence from a source base station.

15. A session management function entity, comprising:

at least one processor;

a non-transitory computer-readable storage medium coupled to the at least one processor and storing programming instructions for execution by the at least one processor, wherein the programming instructions instruct the at least one processor to:

obtain subscription information of a terminal device from a unified data management entity, wherein the subscription information comprises an inter-packet time interval of a service flow;

allocate a quality of service flow identifier to the service flow;

establish a correspondence between the quality of service flow identifier and the inter-packet time interval, wherein the correspondence indicates a corresponding relationship between the quality of service flow identifier and the inter-packet time interval; and

send the correspondence to a communications apparatus, wherein the correspondence is used to periodically schedule a data packet.

16. The session management function entity according to claim 15 , wherein the communications apparatus is a base station, and wherein the programming instructions instruct the at least one processor to:

send the correspondence to the base station through an access and mobility management function entity.

17. The session management function entity according to claim 15 , wherein the communications apparatus is a user plane function entity.

18. The session management function entity according to claim 17 , wherein the user plane function entity is a target user plane function entity, and before sending the correspondence to the communications apparatus, the programming instructions further instruct the at least one processor to:

receive, from an access and mobility management function entity, a request for reselecting a user plane function entity;

select the target user plane function entity; and

send the correspondence to the target user plane function entity.