System, method, and apparatus for device control based on optical communication

1 . A method, comprising:

obtaining, by a first optical head-end, a first primary station packet from a first controller, wherein the first primary station packet comprises a first primary station data unit, the first primary station data unit comprises a first destination identifier and first service data, the first destination identifier comprised in the first primary station data unit is an identifier of a first field device, the first field device is controlled by the first controller, and the first destination identifier comprised in the first primary station data unit identifies a destination recipient of the first service data;

determining, by the first optical head-end based on the first destination identifier comprised in the first primary station data unit, a first optical terminal connected to the first field device;

constructing, by the first optical head-end, a first downlink transmission frame, wherein the first downlink transmission frame comprises the first primary station data unit and a first header field corresponding to the first primary station data unit, the first header field corresponding to the first primary station data unit comprises an identifier of the first optical terminal or a first broadcast optical terminal identifier, and the identifier of the first optical terminal or the first broadcast optical terminal identifier indicates to the first optical terminal to process the first primary station data unit;

sending, by the first optical head-end, the first downlink transmission frame to the first optical terminal through an optical signal;

obtaining, by the first optical head-end, a second primary station packet sent by the first controller, wherein the second primary station packet comprises a third primary station data unit, the third primary station data unit comprises a fourth destination identifier and third service data, and the fourth destination identifier comprised in the third primary station data unit is an identifier of a second controller;

determining, by the first optical head-end based on the identifier of the second controller, a media access control (MAC) address of a second optical head-end corresponding to the second controller; and

sending, by the first optical head-end, the third primary station data unit to the second optical head-end based on the MAC address of the second optical head-end.

2 . The method according to claim 1 , wherein the first primary station packet further comprises a second primary station data unit, the second primary station data unit comprises a second destination identifier and second service data, the second destination identifier comprised in the second primary station data unit is an identifier of a second field device, and the second field device is controlled by the first controller; and

wherein the method further comprises:

determining, by the first optical head-end based on the second destination identifier comprised in the second primary station data unit, a second optical terminal connected to the second field device, wherein the first downlink transmission frame constructed and sent by the first optical head-end further comprises the second primary station data unit and a second header field corresponding to the second primary station data unit, the second header field corresponding to the second primary station data unit comprises an identifier of the second optical terminal or the first broadcast optical terminal identifier, and the identifier of the second optical terminal or the first broadcast optical terminal identifier indicates to the second optical terminal to process the second primary station data unit.

3 . The method according to claim 2 , wherein:

when the second primary station data unit and the first primary station data unit correspond to a same header field, the first broadcast optical terminal identifier is comprised in the same header field; and

when the second primary station data unit and the first primary station data unit correspond to different header fields, the first header field corresponding to the first primary station data unit comprises the identifier of the first optical terminal, and the second header field corresponding to the second primary station data unit comprises the identifier of the second optical terminal.

4 . The method according to claim 2 , wherein after sending, by the first optical head-end, the first downlink transmission frame, the method further comprises:

receiving, by the first optical head-end, a first uplink transmission frame, wherein the first uplink transmission frame comprises a first uplink transmission subframe, the first uplink transmission subframe comprises a third header field and a first secondary station data unit, the third header field in the first uplink transmission subframe comprises the identifier of the first optical terminal, the first secondary station data unit comprises service data of the first field device and a first source identifier, and the first source identifier in the first secondary station data unit is the identifier of the first field device.

5 . The method according to claim 4 , wherein the first uplink transmission frame received by the first optical head-end further comprises a second uplink transmission subframe, the second uplink transmission subframe comprises a fourth header field and a second secondary station data unit, the fourth header field in the second uplink transmission subframe comprises the identifier of the second optical terminal, the second secondary station data unit comprises service data of the second field device and a second source identifier, and the second source identifier in the second secondary station data unit is the identifier of the second field device.

6 . The method according to claim 4 , wherein the first secondary station data unit further comprises a third destination identifier, and the method further comprises:

determining, by the first optical head-end based on the third destination identifier comprised in the first secondary station data unit, a path for forwarding the first secondary station data unit.

7 . The method according to claim 6 , wherein determining, by the first optical head-end based on the third destination identifier comprised in the first secondary station data unit, the forwarding path comprises:

when the third destination identifier comprised in the first secondary station data unit is an identifier of the first controller, sending, by the first optical head-end, the first secondary station data unit to the first controller.

8 . The method according to claim 6 , wherein determining, by the first optical head-end based on the third destination identifier comprised in the first secondary station data unit, the forwarding path comprises:

when the third destination identifier comprised in the first secondary station data unit is the identifier of the second field device, constructing, by the first optical head-end, a second downlink transmission frame based on the first secondary station data unit, wherein the second downlink transmission frame comprises the first secondary station data unit.

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

receiving, by the first optical head-end, a second uplink transmission frame, wherein the second uplink transmission frame comprises a third uplink transmission subframe, the third uplink transmission subframe comprises a fifth header field and a third secondary station data unit, the fifth header field in the third uplink transmission subframe comprises the identifier of the first optical terminal, the third secondary station data unit comprises service data of the first field device, a third source identifier, and a fifth destination identifier, the third source identifier in the third secondary station data unit is the identifier of the first field device, the fifth destination identifier comprised in the third secondary station data unit is an identifier of a third field device, and the third field device is controlled by the second controller;

determining, by the first optical head-end based on the fifth destination identifier comprised in the third secondary station data unit, the MAC address of the second optical head-end corresponding to the second controller; and

sending, by the first optical head-end, the third secondary station data unit to the second optical head-end based on the MAC address of the second optical head-end.

10 . A method, comprising:

receiving, by a first optical terminal, a downlink optical signal from a first optical head-end, wherein the downlink optical signal comprises a first downlink transmission frame, the first downlink transmission frame comprises a first primary station data unit and a first header field corresponding to the first primary station data unit, the first header field corresponding to the first primary station data unit comprises an identifier of the first optical terminal or a broadcast optical terminal identifier, the first primary station data unit comprises a first destination identifier and first service data, the first destination identifier comprised in the first primary station data unit is an identifier of a first field device, and the first optical terminal is connected to the first field device;

determining, by the first optical terminal based on the identifier of the first optical terminal or the broadcast optical terminal identifier comprised in the first header field corresponding to the first primary station data unit, that the first primary station data unit is a to-be-processed data unit; and

performing the following:

sending, by the first optical terminal, the first service data to the first field device based on the identifier of the first field device comprised in the first primary station data unit; or

operating or controlling the first field device based on the first service data;

wherein the first primary station data unit further comprises at least one of the following fields: a data type field, an operation type field, a secondary station operation address offset field, a payload length field, a packet sequence number field, a priority field, a last packet data unit indication field, a secondary station event field, or a response error code field; and

wherein sending, by the first optical terminal, the first service data to the first field device, or operating or controlling the first field device based on the first service data, comprises:

sending, by the first optical terminal to the first field device, an operation type and a secondary station operation address offset that are comprised in the first primary station data unit, or operating or controlling the first field device based on the operation type and the secondary station operation address offset that are comprised in the first primary station data unit.

11 . The method according to claim 10 , further comprising:

when the first header field corresponding to the first primary station data unit comprises the broadcast optical terminal identifier, determining, by the first optical terminal based on the first destination identifier comprised in the first primary station data unit, that the first primary station data unit is the to-be-processed data unit.

12 . The method according to claim 10 , further comprising:

obtaining, by the first optical terminal, service data of the first field device; and

encapsulating, by the first optical terminal, the service data of the first field device into a first uplink transmission subframe, wherein the first uplink transmission subframe comprises a second header field and a first secondary station data unit, the second header field in the first uplink transmission subframe comprises the identifier of the first optical terminal, the first secondary station data unit comprises the service data of the first field device and a first source identifier, and the first source identifier in the first secondary station data unit is the identifier of the first field device; and

sending, by the first optical terminal, the first uplink transmission subframe to the first optical head-end through an optical signal.

13 . The method according to claim 10 , further comprising:

encapsulating, by the first optical terminal, service data of the first field device into a second uplink transmission subframe, wherein the second uplink transmission subframe comprises a third header field and a third secondary station data unit, the third header field in the second uplink transmission subframe comprises the identifier of the first optical terminal, the third secondary station data unit comprises the service data of the first field device, a second source identifier, and a second destination identifier, the second source identifier in the third secondary station data unit is the identifier of the first field device, and the second destination identifier comprised in the third secondary station data unit is an identifier of another field device; and

sending, by the first optical terminal, the second uplink transmission subframe to the first optical head-end through an optical signal.

14 . The method according to claim 10 , wherein the first optical head-end is an optical line terminal (OLT), and the first optical terminal is an optical network unit (ONU) or an optical network terminal (ONT); and

wherein an identifier of the first optical head-end and the identifier of the first optical terminal each are a passive optical network (PON) identifier, and a type of each respective PON identifier comprises a gigabit-capable passive optical network encapsulation mode (GEM) port identifier or an Ethernet passive optical network (EPON) logical link identifier (LLID).

15 . The method according to claim 10 , wherein the first downlink transmission frame is in a gigabit-capable passive optical network encapsulation mode (GEM) frame format, and the first header field comprised in the first downlink transmission frame is a GEM frame header field.

16 . The method according to claim 10 , wherein a data type indicated by the data type field comprises any one of the following data types: periodic real-time data type, random access data type, management data type, or security data type; and

wherein:

when the data type indicated by the data type field is the periodic real-time data type or the random access data type, a command type indicated by the operation type field comprises any one of the following types: a read operation type, a write operation type, a read/write operation type, a broadcast write operation type, or a loopback test type; or

when the data type indicated by the data type field is the management data type, a command type indicated by the operation type field comprises any one of the following types: a read operation type, a read response operation type, a set operation, or a set response operation type.

17 . An apparatus, comprising:

a transceiver, configured to send and receive optical signals;

at least one processor; and

a non transitory memory storing instructions that are executable by the at least one processor, wherein when the instructions are executed, the apparatus serves as a first optical head-end and performs operations comprising:

obtain a first primary station packet from a first controller, wherein the first primary station packet comprises a first primary station data unit, the first primary station data unit comprises a first destination identifier and first service data, the first destination identifier comprised in the first primary station data unit is an identifier of a first field device, the first field device is controlled by the first controller, and the first destination identifier comprised in the first primary station data unit identifies a destination recipient of the first service data;

determine, based on the first destination identifier comprised in the first primary station data unit, a first optical terminal connected to the first field device; and

construct a first downlink transmission frame, wherein the first downlink transmission frame comprises the first primary station data unit and a first header field corresponding to the first primary station data unit, the first header field corresponding to the first primary station data unit comprises an identifier of the first optical terminal or a broadcast optical terminal identifier, and the identifier of the first optical terminal or the broadcast optical terminal identifier indicates to the first optical terminal to process the first primary station data unit;

send the first downlink transmission frame to the first optical terminal through an optical signal;

obtain a second primary station packet sent by the first controller, wherein the second primary station packet comprises a third primary station data unit, the third primary station data unit comprises a fourth destination identifier and third service data, and the fourth destination identifier comprised in the third primary station data unit is an identifier of a second controller;

determine, based on the identifier of the second controller, a media access control (MAC) address of a second optical head-end corresponding to the second controller; and

send the third primary station data unit to the second optical head-end based on the MAC address of the second optical head-end.

18 . The apparatus according to claim 17 , wherein the first primary station packet further comprises a second primary station data unit, the second primary station data unit comprises a second destination identifier and second service data, the second destination identifier comprised in the second primary station data unit is an identifier of a second field device, and the second field device is controlled by the first controller; and

wherein the operations further comprise:

determining, based on the second destination identifier comprised in the second primary station data unit, a second optical terminal connected to the second field device, wherein the first downlink transmission frame constructed and sent by the first optical head-end further comprises the second primary station data unit and a second header field corresponding to the second primary station data unit, the second header field corresponding to the second primary station data unit comprises an identifier of the second optical terminal or the broadcast optical terminal identifier, and the identifier of the second optical terminal or the broadcast optical terminal identifier indicates to the second optical terminal to process the second primary station data unit.

19 . An apparatus, comprising:

a transceiver, configured to send and receive optical signals;

at least one processor; and

a non-transitory computer readable storage medium storing instructions that are executable by the at least one processor, and when the instructions are executed, the apparatus serves as a first optical terminal and performs operations comprising:

receive a downlink optical signal from a first optical head-end, wherein the downlink optical signal comprises a first downlink transmission frame, the first downlink transmission frame comprises a first primary station data unit and a first header field corresponding to the first primary station data unit, the first header field corresponding to the first primary station data unit comprises an identifier of the first optical terminal or a broadcast optical terminal identifier, the first primary station data unit comprises a first destination identifier and first service data, the first destination identifier comprised in the first primary station data unit is an identifier of a first field device, and the first optical terminal is connected to the first field device;

determine, based on the identifier of the first optical terminal or the broadcast optical terminal identifier comprised in the first header field corresponding to the first primary station data unit, that the first primary station data unit is a to-be-processed data unit; and

perform the following:

send, the first service data to the first field device based on the identifier of the first field device comprised in the first primary station data unit; or

operate or control the first field device based on the first service data;

wherein the first primary station data unit further comprises at least one of the following fields: a data type field, an operation type field, a secondary station operation address offset field, a payload length field, a packet sequence number field, a priority field, a last packet data unit indication field, a secondary station event field, or a response error code field; and

wherein sending the first service data to the first field device, or operating or controlling the first field device based on the first service data, comprises:

sending, to the first field device, an operation type and a secondary station operation address offset that are comprised in the first primary station data unit, or operating or controlling the first field device based on the operation type and the secondary station operation address offset.

20 . The apparatus according to claim 19 , wherein the operations further comprise:

when the first header field corresponding to the first primary station data unit comprises the broadcast optical terminal identifier, determining, based on the first destination identifier comprised in the first primary station data unit, that the first primary station data unit is the to-be-processed data unit.