Data transmission method, device, and network system

1. A data transmission method, comprising:

obtaining, by a control plane device, quality of service (QoS) required by a data transmission service and information about data transmission capabilities of at least two user plane devices controlled by the control plane device, wherein the QoS required by the data transmission service is obtained from a terminal;

after determining that the data transmission service needs to be established between the terminal and a user plane device, selecting, by the control plane device from the at least two user plane devices, a user plane device whose data transmission capability satisfies the QoS required by the data transmission service, wherein when the selected user plane device and the control plane device are respectively located on different physical entities, selecting, by the control plane device from the at least two user plane devices, the user plane device whose data transmission capability satisfies the QoS required by the data transmission service comprises:

selecting, by the control plane device from the at least two user plane devices, a user plane device whose data transmission capability satisfies the QoS required by the data transmission service and that is located on a physical entity different from a physical entity on which the control plane device is located; and

determining, by the control plane device, to establish a bearer of the data transmission service on the selected user plane device.

2. The method according to claim 1 , wherein:

the control plane device and the at least two user plane devices controlled by the control plane device are respectively located on different physical entities; or

the control plane device and at least one of the at least two user plane devices controlled by the control plane device are located on a same physical entity, and the control plane device and a user plane device other than the at least one user plane device are located on different physical entities.

3. A network system, comprising:

a control plane device;

at least two user plane devices controlled by the control plane device;

wherein the control plane device is configured to:

obtain quality of service (QoS) required by a data transmission service and information about data transmission capabilities of the at least two user plane devices controlled by the control plane device, wherein the QoS required by the data transmission service is obtained from a terminal;

after determining that the data transmission service needs to be established between a user plane device and the terminal, select, from the at least two user plane devices, a user plane device whose data transmission capability satisfies the QoS required by the data transmission service; and

establish a bearer of the data transmission service on the selected user plane device; wherein when the selected user plane device and the control plane device are respectively located on different physical entities, when the control plane device selects, from the at least two user plane devices, the user plane device whose data transmission capability satisfies the QoS required by the data transmission service, the control plane device is configured to:

select, from the at least two user plane devices, a user plane device whose data transmission capability satisfies the QoS required by the data transmission service and that is located on a physical entity different from a physical entity on which the control plane device is located; and

wherein the selected user plane device is configured to:

obtain data transmission capability information of the user plane device, and send the data transmission capability information to the control plane device.

4. The system according to claim 3 , wherein:

the control plane device and the at least two user plane devices controlled by the control plane device are respectively located on different physical entities; or

the control plane device and at least one of the at least two user plane devices controlled by the control plane device are located on a same physical entity, and the control plane device and a user plane device other than the at least one user plane device are located on different physical entities.

5. A control plane device for data transmission, comprising:

a transceiver, the transceiver configured to obtain quality of service (QoS) required by a data transmission service and information about data transmission capabilities of at least two user plane devices controlled by the control plane device, wherein the QoS required by the data transmission service is obtained from a terminal; and

at least one processor, the at least one processor configured to:

after determining that the data transmission service needs to be established between the terminal and a user plane device, select, from the at least two user plane devices, a user plane device whose data transmission capability satisfies the QoS required by the data transmission service; and

establish a bearer of the data transmission service on the selected user plane device;

wherein when the selected user plane device and the control plane device are respectively located on different physical entities, when the at least one processor selects, from the at least two user plane devices, the user plane device whose data transmission capability satisfies the QoS required by the data transmission service, the at least one processor is configured to:

select, from the at least two user plane devices, a user plane device whose data transmission capability satisfies the QoS required by the data transmission service and that is located on a physical entity different from a physical entity on which the control plane device is located.

6. The control plane device according to claim 5 , wherein:

the control plane device and the at least two user plane devices controlled by the control plane device are respectively located on different physical entities; or

the control plane device and at least one of the at least two user plane devices controlled by the control plane device are located on a same physical entity, and the control plane device and a user plane device other than the at least one user plane device are located on different physical entities.