A Time Synchronization Method for a Cross-OSU Heterogeneous Communication Network and the Time-Sensitive Network therein

Abstract

The present disclosure relates to the technical field of time synchronization in a distribution network, and specifically relates to a method for time synchronization of a cross-OSU heterogeneous communication network and a time-sensitive network therein, and a method for an OSU device and a communication device. The method includes: when a first communication device in a first time-sensitive network sends a heterogeneous path delay request message to a second communication device in a second time-sensitive network through an optical transmission network, successively accumulating and inserting a first one-way link delay, a third one-way link delay obtained based on an OSU multiple frame, and a second one-way link delay in a correction field of the message, so that the second communication device calculates a time deviation from the first communication device according to the sum of the link delays, and adjusts the local time of the second time-sensitive network to achieve time synchronization with the first time-sensitive network. The present disclosure realizes precise time synchronization in a cross-OSU heterogeneous communication network, and provides a powerful data transmission and support capability for a distribution communication network.

Description

Technical Field

[0001] The present disclosure relates to the technical field of time synchronization in distribution network networking, and specifically relates to a heterogeneous communication network across optical service units (OSUs) and a time synchronization method for a time-sensitive network (TSN) therein, and methods for OSU devices and communication devices. Background Art

[0002] With the construction of a new power system, the pace of intelligent transformation of the distribution network has accelerated significantly, enabling emerging services such as video surveillance and Internet of Things (IoT) environmental monitoring to no longer be limited to the substation level, but to drive the evolution of the distribution communication network towards large bandwidth, high efficiency, ultra-real-time, high determinacy, strong reliability, and comprehensive bearing capacity. However, traditional Synchronous Digital Hierarchy (SDH) / Multi-Service Transport Platform (MSTP) technologies are limited by technical bottlenecks such as maximum bandwidth and cross-switching capacity and can no longer meet the digital and intelligent transformation of the distribution network.

[0003] In this context, OSU technology has emerged. As the next-generation standard of SDH jointly defined by the three major authoritative standard organizations of ITU-T (International Telecommunication Union Telecommunication Standardization Sector), IEEE (Institute of Electrical and Electronics Engineers), and CCSA (China Communications Standards Association), it not only breaks through bandwidth limitations but also provides stronger support for the distribution communication network by optimizing transmission efficiency and enhancing network flexibility. Currently, this technology has been deployed in batches in the distribution communication network, effectively meeting the requirements of power production for high bandwidth, high real-time performance, high reliability, and comprehensive bearing capacity of the communication network.

[0004] As an emerging industrial Ethernet technology, the time-sensitive network, with technical advantages such as compatibility with traditional Ethernet, hard isolation of services based on precise time slot control, and end-to-end deterministic and reliable transmission, meets the communication requirements of low latency, high determinacy, and high reliability of the distribution communication network. Therefore, introducing the time-sensitive network into the distribution communication network to replace the existing Ethernet switch is one of the technical routes for the distribution access communication network. However, the introduction of the time-sensitive network also brings new challenges: namely, how to effectively implement the time synchronization technology of the time-sensitive network across OSU heterogeneous communication networks, so as to ensure the precise synchronization and transmission of time-sensitive data in a complex network environment to meet the requirements of low latency, high determinacy, and high reliability of the distribution communication network. Summary of the Invention

[0005] To solve the problems in the related art, embodiments of the present disclosure provide a time synchronization method for a cross-OSU heterogeneous communication network and a time-sensitive network therein, and methods for OSU devices and communication devices.

[0006] In a first aspect, embodiments of the present disclosure provide a time synchronization method for a time-sensitive network in a cross-OSU heterogeneous communication network. The cross-OSU heterogeneous communication network includes an optical transport network, a first time-sensitive network and a second time-sensitive network to be synchronized. The first time-sensitive network includes a first communication device, and the second time-sensitive network includes a second communication device. The optical transport network includes a first OSU device and a second OSU device. The first communication device is connected to the first OSU device through a first communication link, the second OSU device is connected to the second communication device through a second communication link, and the first OSU device is connected to the second OSU device through a third communication link. The method includes:

[0007] The first communication device obtains a first one-way link delay of the first communication link when communicating with the first OSU device;

[0008] The second OSU device obtains a second one-way link delay of the second communication link when communicating with the second communication device;

[0009] The first OSU device obtains a third one-way link delay of the third communication link when communicating with the second OSU device, including: obtaining an OSU multiplex frame, obtaining a delay measurement reference time based on the OSU multiplex frame, where the OSU multiplex frame includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiplex frame carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; the first OSU device obtains the third one-way link delay;

[0010] The first communication device sends a heterogeneous path delay request message to the second communication device through the optical transport network, where the first communication device, the first OSU device, and the second OSU device sequentially accumulate and insert the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of the heterogeneous path delay request message;

[0011] The second communication device parses the heterogeneous path delay request message and obtains a total link delay according to the correction field. The total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay;

[0012] When the second communication device obtains the communication with the first communication device, it acquires the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay;

[0013] The second communication device adjusts the local time based on the time deviation, so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0014] According to an embodiment of the present disclosure, the first communication device acquires the first one-way link delay of the first communication link when communicating with the first OSU device, including:

[0015] The first initiating node on the first communication link sends a first path delay request message to the first responding node on the first communication link, and receives the first path delay response message and the first path delay response follow-up message replied by the first responding node;

[0016] The first initiating node records the first sending time of the first path delay request message and the second receiving time of the first path delay response message, obtains the first receiving time of the first path delay request message from the first path delay response message, and obtains the second sending time of the first path delay request message from the first path delay response follow-up message, so as to calculate the first one-way link delay according to the first sending time, the first receiving time, the second sending time, and the second receiving time;

[0017] The first communication device acquires the first one-way link delay.

[0018] According to an embodiment of the present disclosure, calculating the first one-way link delay according to the first sending time, the first receiving time, the second sending time, and the second receiving time includes:

[0019] Calculating the first complete link time for the first initiating node to send and receive messages according to the second receiving time and the first sending time;

[0020] Calculating the first processing time for the first responding node to process the message according to the first receiving time and the second sending time;

[0021] Subtracting the first processing time from the first complete link time to obtain the first two-way link delay of the first communication link;

[0022] Half of the first two-way link delay is the first one-way link delay.

[0023] According to an embodiment of the present disclosure, the second OSU device obtaining the second one-way link delay of the second communication link when communicating with the second communication device includes:

[0024] A second initiating node on the second communication link sends a second path delay request message to a second responding node on the second communication link, and receives a second path delay response message and a second path delay response follow-up message replied by the second responding node;

[0025] The second initiating node records a third sending time of the second path delay request message and a fourth receiving time of the second path delay response message, obtains a third receiving time of the second path delay request message from the second path delay response message, and obtains a fourth sending time of the second path delay request message from the second path delay response follow-up message, so as to calculate the second one-way link delay according to the third sending time, the third receiving time, the fourth sending time, and the fourth receiving time;

[0026] The second OSU device obtains the second one-way link delay.

[0027] According to an embodiment of the present disclosure, the calculating the second one-way link delay according to the third sending time, the third receiving time, the fourth sending time, and the fourth receiving time includes:

[0028] Calculating a second complete link time for the second initiating node to send and receive messages according to the fourth receiving time and the third sending time;

[0029] Calculating a second processing time for the second responding node to process messages according to the third receiving time and the fourth sending time;

[0030] Subtracting the second processing time from the second complete link time to obtain a second two-way link delay of the second communication link;

[0031] Half of the second two-way link delay is the second one-way link delay.

[0032] According to an embodiment of the present disclosure, the OSU frame further includes a position identification bit;

[0033] Obtaining the OSU multiple-frame and obtaining a delay measurement reference time based on the OSU multiple-frame includes: a third initiating node on the third communication link periodically sends the OSU multiple-frame, and uses the delay measurement bit included in the OSU multiple-frame to carry the OSU sending time; a third responding node on the third communication link receives a first OSU multiple-frame by identifying the position identification bit of the OSU frame, parses the first OSU multiple-frame to obtain the corresponding OSU sending time, and uses it as the delay measurement reference time of the first OSU multiple-frame;

[0034] Calculating the third one-way link delay according to the delay measurement reference time includes: the third responding node calculates the third one-way link delay according to the delay measurement reference time of the first OSU multiple-frame and the OSU receiving time when receiving the first OSU multiple-frame.

[0035] According to an embodiment of the present disclosure, the third responding node subtracts the OSU sending time from the OSU receiving time to calculate the third one-way link delay.

[0036] According to an embodiment of the present disclosure, the OSU frame further includes a position identification bit;

[0037] Obtaining the OSU multiple-frame and obtaining a delay measurement reference time based on the OSU multiple-frame includes:

[0038] A sending end of a third initiating node on the third communication link periodically sends the OSU multiple-frame, and uses the delay measurement bit included in the OSU multiple-frame to carry a serial number;

[0039] A receiving end of a third responding node on the third communication link receives a second OSU multiple-frame by identifying the position identification bit in the OSU frame, parses the second OSU multiple-frame to obtain the corresponding serial number, and sends the serial number corresponding to the second OSU multiple-frame and the receiving time of the responding end to a sending end of the third responding node;

[0040] The sending end of the third responding node obtains the sending time of the responding end of the third OSU multiple-frame, calculates the residence time of the responding end according to the receiving time of the responding end and the sending time of the responding end, inserts the serial number corresponding to the second OSU multiple-frame and the residence time of the responding end into the delay measurement bit of the third OSU multiple-frame, and sends the third OSU multiple-frame at the sending time of the responding end;

[0041] The receiving end of the third initiating node parses the third OSU multiple-frame, obtains the serial number corresponding to the second OSU multiple-frame and the residence time of the responding end, and uses the residence time of the responding end as the delay measurement reference time of the second OSU multiple-frame.

[0042] According to an embodiment of the present disclosure, calculating the third one-way link delay based on the time delay measurement reference time includes:

[0043] Start a sender timer when the sender of the third initiating node sends the second OSU multiplex frame, stop the sender timer when the receiver of the third initiating node receives the third OSU multiplex frame, and obtain the transceiver link time based on the sender timer;

[0044] The third initiating node calculates the third one-way link delay according to the responder residence time and the transceiver link time.

[0045] According to an embodiment of the present disclosure, the third initiating node subtracts the responder residence time from the transceiver link time to obtain a third two-way link delay, and half of the third two-way link delay is the third one-way link delay.

[0046] According to an embodiment of the present disclosure, the first communication device, the first OSU device, and the second OSU device successively and cumulatively insert the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of the heterogeneous path delay request message, including:

[0047] The first communication device inserts the first one-way link delay in the correction field of the heterogeneous path delay request message, and then sends the heterogeneous path delay request message inserted with the first one-way link delay to the first OSU device;

[0048] The first OSU device cumulatively inserts the third one-way link delay in the correction field of the heterogeneous path delay request message inserted with the first one-way link delay, and then sends the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay to the second OSU device;

[0049] The second OSU device cumulatively inserts the second one-way link delay in the correction field of the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, and then sends the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device.

[0050] According to an embodiment of the present disclosure, the first OSU device encapsulates the heterogeneous path delay request message inserted with the first one-way link delay according to the OSU protocol, and then cumulatively inserts the third one-way link delay in the correction field of the heterogeneous path delay request message inserted with the first one-way link delay;

[0051] The second OSU device unpacks the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay according to the OSU protocol, and then sends it to the second communication device.

[0052] According to an embodiment of the present disclosure, when the second communication device obtains communication with the first communication device, obtaining the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network includes:

[0053] The first communication device sends a synchronization message to the second communication device, records the master clock timestamp value when sending the synchronization message, then packs the master clock timestamp value into a follow-up message, and sends the follow-up message to the second communication device;

[0054] The second communication device receives the synchronization message, records the local time when receiving the synchronization message, and parses the follow-up message to obtain the master clock timestamp value.

[0055] According to an embodiment of the present disclosure, the second communication device calculates the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay, including:

[0056] The second communication device subtracts the master clock timestamp value and the total link delay from the local time to obtain the time deviation from the first communication device.

[0057] According to an embodiment of the present disclosure, the second communication device adjusts the local time based on the time deviation, including: the second communication device adds the time deviation to the local time as the adjusted local time.

[0058] In a second aspect, an OSU heterogeneous communication network provided in an embodiment of the present disclosure includes: an optical transmission network, a first time-sensitive network and a second time-sensitive network to be synchronized;

[0059] The first time-sensitive network includes a first communication device, the second time-sensitive network includes a second communication device, the optical transmission network includes a first OSU device and a second OSU device, the first communication device is connected to the first OSU device through a first communication link, the second OSU device is connected to the second communication device through a second communication link, and the first OSU device is connected to the second OSU device through a third communication link;

[0060] The first communication device sends a heterogeneous path delay request message to the second communication device through the optical transmission network. Among them, the first communication device, the first OSU device, and the second OSU device successively accumulate and insert the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of the heterogeneous path delay request message; the second communication device parses the heterogeneous path delay request message, and obtains the total link delay according to the correction field. The total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay;

[0061] When the second communication device communicates with the first communication device, the second communication device obtains the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay;

[0062] The second communication device adjusts the local time based on the time deviation, so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0063] According to an embodiment of the present disclosure, the first communication device obtains the first one-way link delay of the first communication link when communicating with the first OSU device;

[0064] The second OSU device obtains the second one-way link delay of the second communication link when communicating with the second communication device;

[0065] The first OSU device obtains the third one-way link delay of the third communication link when communicating with the second OSU device.

[0066] According to an embodiment of the present disclosure, the optical transmission network further includes any one of the following optical transmission devices: Synchronous Digital Hierarchy (SDH) device, Optical Transport Network (OTN) device, Multi-Service Transport Platform (MSTP) device;

[0067] Both ends of the optical transmission device are respectively connected to the first OSU device and the second OSU device.

[0068] In a third aspect, an embodiment of the present disclosure provides a method for an OSU device. The OSU device is the first OSU device in an optical transmission network. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link, and the first OSU device is connected to a second OSU device in the optical transmission network through a third communication link. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link. The method includes:

[0069] Obtaining the third one-way link delay of the third communication link when communicating with the second OSU device includes: obtaining an OSU multiplex frame, and obtaining a delay measurement reference time based on the OSU multiplex frame, where the OSU multiplex frame includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiplex frame carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; obtaining the third one-way link delay;

[0070] Receiving, from the first communication device, a heterogeneous path delay request message inserted with a first one-way link delay, where the heterogeneous path delay request message inserted with the first one-way link delay is obtained by the first communication device inserting the first one-way link delay into the correction field of the heterogeneous path delay request message;

[0071] Accumulatively inserting the third one-way link delay into the correction field of the heterogeneous path delay request message inserted with the first one-way link delay, and then sending the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay to the second OSU device, where the second OSU device accumulatively inserts a second one-way link delay into the correction field of the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, and then sends the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device, and the second communication device obtains the total link delay according to the correction field and calculates the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network;

[0072] Wherein, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay, the first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device, and the second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device.

[0073] In a fourth aspect, an embodiment of the present disclosure provides a method for an OSU device. The OSU device is a second OSU device in an optical transport network. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link, and the second OSU device is connected to a first OSU device in the optical transport network through a third communication link. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link. The method includes:

[0074] Obtain the second one-way link delay of the second communication link when communicating with the second communication device;

[0075] Receive, from the first OSU device, a heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, where the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay is obtained by successively accumulating and inserting in the correction field of the heterogeneous path delay request message by the first communication device and the first OSU device;

[0076] Accumulate and insert the second one-way link delay in the correction field of the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, and then send the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device, so that the second communication device can obtain the total link delay according to the correction field and calculate the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network;

[0077] Wherein, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay, the first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device, and the third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0078] In a fifth aspect, an embodiment of the present disclosure provides a method for a communication device. The communication device is a first communication device in a first time-sensitive network. The first communication device is connected to a first OSU device in an optical transport network through a first communication link. The first OSU device is connected to a second OSU device in the optical transport network through a third communication link. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link. The method includes:

[0079] Obtain the first one-way link delay of the first communication link when communicating with the first OSU device;

[0080] Insert the first one-way link delay into the correction field of the heterogeneous path delay request message, and then send the heterogeneous path delay request message with the first one-way link delay inserted to the first OSU device. Among them, after the first OSU device and the second OSU device successively accumulate and insert the third one-way link delay and the second one-way link delay into the correction field of the heterogeneous path delay request message with the first one-way link delay inserted, the second OSU device sends the heterogeneous path delay request message with the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay inserted to the second communication device; the second communication device obtains the total link delay according to the correction field and calculates the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network;

[0081] Among them, the total link delay is the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay. The second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device, and the third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0082] In a sixth aspect, an embodiment of the present disclosure provides a method for a communication device. The communication device is a second communication device in a second time-sensitive network. The second communication device is connected to a second OSU device in an optical transmission network through a second communication link. The second OSU device is connected to a first OSU device through a third communication link. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link. The method includes:

[0083] Obtain a heterogeneous path delay request message with the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay inserted from the second OSU device. The heterogeneous path delay request message with the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay inserted is obtained by successively accumulating and inserting the first one-way link delay, the third one-way link delay and the second one-way link delay into the correction field of the heterogeneous path delay request message by the first communication device, the first OSU device and the second OSU device;

[0084] Obtain the total link delay according to the correction field of the heterogeneous path delay request message. The total link delay is the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay;

[0085] When communicating with the first communication device, obtain the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network, and calculate the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay;

[0086] Adjust the local time based on the time deviation so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0087] In a seventh aspect, an embodiment of the present disclosure provides a device for an OSU device. The OSU device is the first OSU device in an optical transmission network. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link. The first OSU device is connected to a second OSU device in the optical transmission network through a third communication link. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link. The device includes:

[0088] A first acquisition module, configured to acquire a third one-way link delay of the third communication link when communicating with the second OSU device, including: acquiring an OSU multiframe, and acquiring a delay measurement reference time based on the OSU multiframe, where the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; and acquiring the third one-way link delay;

[0089] A first receiving module, configured to receive, from the first communication device, a heterogeneous path delay request message inserted with a first one-way link delay, where the heterogeneous path delay request message inserted with the first one-way link delay is obtained by the first communication device inserting the first one-way link delay into a correction field of the heterogeneous path delay request message;

[0090] The first sending module is configured to accumulate and insert the third one-way link delay in the correction field of the heterogeneous path delay request message with the first one-way link delay inserted, and then send the heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted to the second OSU device. Wherein, the second OSU device accumulates and inserts the second one-way link delay in the correction field of the heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted, and then sends the heterogeneous path delay request message with the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay inserted to the second communication device. The second communication device obtains the total link delay according to the correction field and calculates the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network;

[0091] Wherein, the total link delay is the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay. The first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device. The second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device.

[0092] In an eighth aspect, an embodiment of the present disclosure provides a device for an OSU device. The OSU device is the second OSU device in an optical transmission network. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link. The second OSU device is connected to a first OSU device in the optical transmission network through a third communication link. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link. The device includes:

[0093] The second obtaining module is configured to obtain the second one-way link delay of the second communication link when communicating with the second communication device;

[0094] The second receiving module is configured to receive, from the first OSU device, a heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted. The heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted is obtained by gradually accumulating and inserting in the correction field of the heterogeneous path delay request message by the first communication device and the first OSU device;

[0095] A second sending module, configured to cumulatively insert the second one-way link delay in a correction field of the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, and then send the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device, so that the second communication device can obtain the total link delay according to the correction field, and calculate the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network;

[0096] Wherein, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay, the first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device, and the third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0097] In a ninth aspect, an embodiment of the present disclosure provides a device for a communication device. The communication device is a first communication device in a first time-sensitive network. The first communication device is connected to a first OSU device in an optical transmission network through a first communication link. The first OSU device is connected to a second OSU device in the optical transmission network through a third communication link. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link. The device includes:

[0098] A third obtaining module, configured to obtain a first one-way link delay of the first communication link when communicating with the first OSU device;

[0099] A third sending module, configured to insert the first one-way link delay in a correction field of a heterogeneous path delay request message, and then send the heterogeneous path delay request message inserted with the first one-way link delay to the first OSU device. Wherein, after the first OSU device and the second OSU device cumulatively insert the third one-way link delay and the second one-way link delay in the correction field of the heterogeneous path delay request message inserted with the first one-way link delay, the second OSU device sends the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device; the second communication device obtains the total link delay according to the correction field, and calculates the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network;

[0100] Among them, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay. The second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device. The third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0101] In a tenth aspect, an embodiment of the present disclosure provides a device for a communication device. The communication device is a second communication device in a second time-sensitive network. The second communication device is connected to a second OSU device in an optical transport network through a second communication link. The second OSU device is connected to a first OSU device through a third communication link. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link. The device includes:

[0102] A fourth acquisition module, configured to acquire a heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay from the second OSU device. The heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay is obtained by successively accumulating and inserting the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction domain field of the heterogeneous path delay request message by the first communication device, the first OSU device, and the second OSU device;

[0103] A fifth acquisition module, configured to acquire the total link delay according to the correction domain field of the heterogeneous path delay request message. The total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay;

[0104] A calculation module, configured to acquire the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network when communicating with the first communication device, and calculate the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay;

[0105] An adjustment module, configured to adjust the local time based on the time deviation so that the second time-sensitive network is synchronized with the first time-sensitive network.

[0106] In an eleventh aspect, an embodiment of the present disclosure provides an electronic device, including a memory and a processor. Among them, the memory is used to store computer instructions, and the computer instructions are executed by the processor to implement the method according to any one of the third aspect to the sixth aspect.

[0107] In a twelfth aspect, an embodiment of the present disclosure provides a computer-readable storage medium, on which computer instructions are stored, and when the computer instructions are executed by a processor, the method described in any one of the third aspect to the sixth aspect is implemented.

[0108] In a thirteenth aspect, an embodiment of the present disclosure provides a computer program product, including computer instructions, and when the computer instructions are executed by a processor, the method described in any one of the third aspect to the sixth aspect is implemented.

[0109] According to the technical solution provided by the embodiment of the present disclosure, when the first communication device sends a heterogeneous path delay request message to the second communication device through an optical transmission network, the first one-way link delay, the third one-way link delay obtained based on the OSU multiple frame, and the second one-way link delay are successively accumulated and inserted into the correction field of the heterogeneous path delay request message by the first communication device, the first OSU device, and the second OSU device, so that the second communication device obtains the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay as the total link delay, and then calculates the time deviation from the first communication device based on the total link delay, and adjusts the local time of the second time-sensitive network according to the time deviation, so that the first time-sensitive network and the second time-sensitive network achieve time synchronization.

[0110] The present disclosure measures the link delay for multiple communication links in a cross-OSU heterogeneous communication network respectively. When measuring different link delays, not only the time synchronization message method is adopted, but also the OSU multiple frame method is adopted, that is, the delay measurement bits in a specified number of OSU frames included in the OSU multiple frame are utilized at the same time. Thus, the above-mentioned multiple delay measurement bits (forming a delay measurement field) can be used to carry time information at the same time, and when multiple link delays are obtained, the correction field in the time synchronization message is innovatively used, and the multiple link delays are carried by accumulation level by level using this correction field, so that the time-sensitive network at the opposite end in the cross-OSU heterogeneous communication network can obtain the sum of the link delays, and perform time synchronization with the time-sensitive network local in the cross-OSU heterogeneous communication network, achieving precise time synchronization in the cross-OSU heterogeneous communication network, providing a powerful data transmission and support ability for the distribution communication network, and solving the problem that the delay measurement result obtained by the direct measurement link delay method using the time synchronization message for measuring the link delay may have a large jitter due to the jitter uncertainty of the time synchronization message in the heterogeneous network transparent transmission, and cannot meet the distribution networking requirements.

[0111] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0112] In conjunction with the accompanying drawings, other features, objects, and advantages of the present disclosure will become more apparent through the following detailed description of non-limiting embodiments. In the drawings:

[0113] Figure 1 A flowchart showing a time synchronization method for a time-sensitive network in a cross-OSU heterogeneous communication network according to an embodiment of the present disclosure;

[0114] Figure 2 A schematic structural diagram showing a cross-OSU heterogeneous communication network according to an embodiment of the present disclosure;

[0115] Figure 3 A schematic diagram showing a method for calculating link delay in a time synchronization method for a time-sensitive network according to an embodiment of the present disclosure;

[0116] Figure 4 A schematic diagram showing another method for calculating link delay in a time synchronization method for a time-sensitive network according to an embodiment of the present disclosure;

[0117] Figure 5 A schematic diagram showing a method for obtaining a third one-way link delay according to an embodiment of the present disclosure;

[0118] Figure 6 A schematic diagram showing another method for obtaining a third one-way link delay according to an embodiment of the present disclosure;

[0119] Figure 7 A schematic diagram showing the step-by-step cumulative insertion of the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of a heterogeneous path delay request message according to an embodiment of the present disclosure;

[0120] Figure 8 A schematic diagram showing obtaining the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network according to an embodiment of the present disclosure;

[0121] Figure 9 A schematic structural diagram showing another cross-OSU heterogeneous communication network according to an embodiment of the present disclosure;

[0122] Figure 10 A flowchart showing a method for an OSU device according to an embodiment of the present disclosure;

[0123] Figure 11 A flowchart showing another method for an OSU device according to an embodiment of the present disclosure;

[0124] Figure 12 A flowchart showing a method for a communication device according to an embodiment of the present disclosure;

[0125] Figure 13 Flowchart showing another method for a communication device according to an embodiment of the present disclosure;

[0126] Figure 14 Block diagram showing the structure of a device for an OSU device according to an embodiment of the present disclosure;

[0127] Figure 15 Block diagram showing the structure of another device for an OSU device according to an embodiment of the present disclosure;

[0128] Figure 16 Block diagram showing the structure of a device for a communication device according to an embodiment of the present disclosure;

[0129] Figure 17 Block diagram showing the structure of another device for a communication device according to an embodiment of the present disclosure;

[0130] Figure 18 Block diagram showing the structure of an electronic device according to an embodiment of the present disclosure;

[0131] Figure 19 Schematic diagram showing the structure of a computer system suitable for implementing the method according to an embodiment of the present disclosure. Detailed implementation manners

[0132] Hereinafter, exemplary embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement them. In addition, for clarity, parts irrelevant to the description of the exemplary embodiments are omitted in the drawings.

[0133] In the present disclosure, it should be understood that terms such as "including" or "having" are intended to indicate the presence of features, numbers, steps, actions, components, parts, or combinations thereof disclosed in this specification, and are not intended to exclude the possibility of the presence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0134] It should be further noted that, without conflict, the embodiments in the present disclosure and the features in the embodiments can be combined with each other. The present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0135] In the present disclosure, if it involves operations of obtaining user information or user data or presenting user information or user data to others, such operations are all operations authorized, confirmed by the user, or actively selected by the user.

[0136] As described above, in order to meet the requirements of low latency, high determinism, and high reliability in the distribution communication network, the time-sensitive network is introduced on the basis of the large-scale deployment of the OSU technology in the distribution communication network. By replacing the existing Ethernet switch with the time-sensitive network, it becomes one of the technical routes for distribution equipment to access the communication network. However, due to the introduction of the OSU technology and the time-sensitive network, the distribution communication network is no longer a homogeneous communication network, but constitutes a heterogeneous network (cross-OSU heterogeneous communication network).

[0137] The inventors found that due to the jitter uncertainty in the transparent transmission of time synchronization messages in the heterogeneous network (the cross-OSU heterogeneous communication network in the present disclosure), therefore, the method of directly using the transparent transmission of time synchronization messages to measure the link delay, that is, directly using the time synchronization message to obtain the transmission delay between two terminals, the obtained delay measurement results often show large fluctuations and instabilities. This jitter phenomenon not only enlarges the error range of the measurement results, but may also have an adverse impact on the network system that relies on accurate delay information.

[0138] In view of the technical problems existing in the above-mentioned prior art, the present disclosure provides a time synchronization method for a time-sensitive network in a cross-OSU heterogeneous communication network: a first communication device obtains a first one-way link delay of a first communication link when communicating with a first OSU device; a second OSU device obtains a second one-way link delay of a second communication link when communicating with a second communication device; a first OSU device obtains a third one-way link delay of a third communication link when communicating with a second OSU device, including: obtaining an OSU multiplex frame, and obtaining a delay measurement reference time based on the OSU multiplex frame, wherein the OSU multiplex frame includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiplex frame carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; the first OSU device obtains the third one-way link delay; the first communication device sends a heterogeneous path delay request message to the second communication device through the optical transmission network, wherein the first communication device, the first OSU device, and the second OSU device sequentially accumulate and insert the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of the heterogeneous path delay request message; the second communication device parses the heterogeneous path delay request message, and obtains a total link delay according to the correction field, and the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay; when the second communication device communicates with the first communication device, the second communication device obtains the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay; the second communication device adjusts the local time based on the time deviation, so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0139] When addressing the measurement challenges of link latency in heterogeneous network environments, the present disclosure adopts a more refined and robust measurement strategy. For multiple communication links in a heterogeneous network, the link latency is measured separately. When measuring different link latencies, not only the time synchronization message method is used, but also the OSU multiplex frame method is adopted. That is, the latency measurement bits in a specified number of OSU frames included in the OSU multiplex frame are utilized simultaneously. As a result, the above-mentioned multiple latency measurement bits (which form a latency measurement field) can be used to carry time information. Moreover, after obtaining the latencies of multiple links, the correction field in the time synchronization message, which is not fully utilized in the prior art, is innovatively used to carry the latencies of the multiple links in a cumulative manner. This enables the time-sensitive network at the opposite end to obtain the sum of the link latencies for time synchronization with the local time-sensitive network, eliminating the jitter impact during the transparent transmission of time synchronization messages, improving the accuracy and reliability of latency measurement, thus meeting the requirements of distribution network networking, enhancing network performance, and providing a powerful data transmission and support capability for the distribution communication network.

[0140] Figure 1 FIG. shows a flowchart of a time synchronization method for a time-sensitive network in a cross-OSU heterogeneous communication network according to an embodiment of the present disclosure.

[0141] In the present disclosure, the cross-OSU heterogeneous communication network includes: an optical transmission network, a first time-sensitive network and a second time-sensitive network to be synchronized. The first time-sensitive network includes a first communication device, the second time-sensitive network includes a second communication device, the optical transmission network includes a first OSU device and a second OSU device. The first communication device is connected to the first OSU device through a first communication link, the second OSU device is connected to the second communication device through a second communication link, and the first OSU device is connected to the second OSU device through a third communication link, as Figure 2 shown.

[0142] According to an embodiment of the present disclosure, the first communication device or the second communication device can be a switch, a router, etc.

[0143] According to an embodiment of the present disclosure, the first OSU device can be a source OSU device, the second OSU device can be a sink OSU device, or the first OSU device can be a sink OSU device and the second OSU device can be a source OSU device.

[0144] Those skilled in the art should understand that the first time-sensitive network and the second time-sensitive network are any two time-sensitive networks for cross-OSU device communication in the cross-OSU heterogeneous communication network. The first OSU device and the second OSU device are two OSU devices respectively connected to the first time-sensitive network and the second time-sensitive network. The "first" and "second" are not technical means for restricting the implementation manners of the time-sensitive network and the OSU device.

[0145] In a specific embodiment, when the cross-OSU heterogeneous communication network of the present disclosure is applied to a distribution network, the cross-OSU heterogeneous communication network constitutes a heterogeneous distribution communication network; the first time-sensitive network and the second time-sensitive network constitute a distribution access network in the heterogeneous distribution communication network, serving as a bridge between the distribution terminal and the distribution communication network to ensure that distribution terminals such as feeder terminal units (FTUs), substation terminal units (DTUs), and transformer terminal units (TTUs) can be smoothly connected to the distribution communication network; the optical transmission network constitutes a distribution transmission network in the heterogeneous distribution communication network, thereby realizing data transmission and interaction of the connected distribution terminals.

[0146] As Figure 1 shown, in the above cross-OSU heterogeneous communication network, the method for time synchronization between the first time-sensitive network and the second time-sensitive network includes the following steps S101 to S107.

[0147] In step S101, the first communication device obtains the first one-way link delay of the first communication link when communicating with the first OSU device.

[0148] Among them, the first one-way link delay of the first communication link can be obtained by sending and receiving time synchronization messages between the first initiating node and the first responding node on the first communication link, and the time of message sending and receiving can be obtained by using the hardware to timestamp.

[0149] Specifically, a first initiating node on the first communication link sends a first path delay request message to a first response node on the first communication link, and receives a first path delay response message and a first path delay response follow-up message replied by the first response node; the first initiating node records a first sending time of the first path delay request message and a second receiving time of the first path delay response message, obtains a first receiving time of the first path delay request message from the first path delay response message, and obtains a second sending time of the first path delay request message from the first path delay response follow-up message, so as to calculate a first one-way link delay according to the first sending time, the first receiving time, the second sending time, and the second receiving time; the first communication device obtains the first one-way link delay.

[0150] According to an embodiment of the present disclosure, a first complete link time for the first initiating node to send and receive messages is calculated according to the second receiving time and the first sending time; a first processing time for the first response node to process messages is calculated according to the first receiving time and the second sending time; the first complete link time minus the first processing time obtains a first two-way link delay of the first communication link; half of the first two-way link delay is the first one-way link delay.

[0151] Figure 3 A schematic diagram showing a method for calculating link delay in a time synchronization method of a time-sensitive network according to an embodiment of the present disclosure; Figure 4 A schematic diagram showing another method for calculating link delay in a time synchronization method of a time-sensitive network according to an embodiment of the present disclosure. The following combines Figure 3 and Figure 4 The illustrated example to describe the process of obtaining the first one-way link delay.

[0152] Since the first communication device is a communication device in the first time-sensitive network, the time synchronization messages sent and received between the first initiating node and the first response node on the first communication link may be IEEE 802.1AS protocol messages, that is, Generalized Precision Time Protocol (gPTP) messages.

[0153] It is known that the IEEE 802.1AS protocol messages include multiple message types, Figure 3 and Figure 4In the illustrated example, the Pdelay_Req message is used as the first path delay request message, the PDelay_Resp message is used as the first path delay response message, and the Pdelay_Resp_Follow_Up message is used as the first path delay response follow-up message. The specific obtaining process is as follows:

[0154] The first initiating node sends a Pdelay_Req message and records the first sending time. The first responding node receives the Pdelay_Req message and records the first receiving time. The first responding node packs the first receiving time into the PDelay_Resp message and sends it to the first initiating node, and records the second sending time. The first responding node packs the second sending time into the Pdelay_Resp_Follow_Up message and sends it to the first initiating node. The first initiating node receives the PDelay_Resp message and records the second receiving time.

[0155] At this time, the first initiating node records two timestamps: the first sending time and the second receiving time, and obtains the first receiving time and the second sending time from the PDelay_Resp message and the Pdelay_Resp_Follow_Up message respectively, so that the first one-way link delay can be calculated based on the above four timestamps.

[0156] According to an embodiment of the present disclosure, calculating the first one-way link delay according to the first sending time, the first receiving time, the second sending time, and the second receiving time includes calculating the first one-way link delay D1 according to the following formula: where t1 is the first sending time, t2 is the first receiving time, t3 is the second sending time, t4 is the second receiving time, t4 - t1 is the first complete link time, and t3 - t2 is the first processing time.

[0157] According to an embodiment of the present disclosure, since the communication between the first communication device and the first OSU device is two-way in the scenario of this heterogeneous network, the first initiating node may be the first communication device, the first responding node may be the first OSU device, or the first initiating node may be the first OSU device, and the first responding node may be the first communication device, that is, both the first communication device and the first OSU device can be used as either the initiating node or the responding node.

[0158] In step S102, the second OSU device obtains the second one-way link delay of the second communication link when communicating with the second communication device.

[0159] Among them, the second one-way link delay of the second communication link can be obtained by sending and receiving time synchronization messages between the second initiating node and the second responding node on the second communication link, and the time of message sending and receiving can be obtained by means of hardware timestamping.

[0160] Specifically, the second initiating node on the second communication link sends a second path delay request message to the second responding node on the second communication link, and receives a second path delay response message and a second path delay response follow-up message replied by the second responding node; the second initiating node records the third sending time of the second path delay request message and the fourth receiving time of the second path delay response message, obtains the third receiving time of the second path delay request message from the second path delay response message, and obtains the fourth sending time of the second path delay request message from the second path delay response follow-up message, so as to calculate the second one-way link delay according to the third sending time, the third receiving time, the fourth sending time, and the fourth receiving time; the second OSU device obtains the second one-way link delay.

[0161] According to an embodiment of the present disclosure, a second complete link time for the second initiating node to send and receive messages is calculated according to the fourth receiving time and the third sending time; a second processing time for the second responding node to process messages is calculated according to the third receiving time and the fourth sending time; the second two-way link delay of the second communication link is obtained by subtracting the second processing time from the second complete link time; half of the second two-way link delay is the second one-way link delay.

[0162] The following combines Figure 3 and Figure 4 the shown example to illustrate the process of obtaining the second one-way link delay.

[0163] Since the second communication device is a communication device in the second time-sensitive network, the time synchronization messages sent and received between the second initiating node and the second responding node on the second communication link can be IEEE 802.1AS protocol messages.

[0164] Similar to the process of obtaining the above first one-way link delay, Figure 3 and Figure 4 in the shown example, the Pdelay_Req message is used as the second path delay request message, the PDelay_Resp message is used as the second path delay response message, and the Pdelay_Resp_Follow_Up message is used as the second path delay response follow-up message. Then the specific obtaining process is as follows:

[0165] The second initiating node sends a Pdelay_Req message and records the third transmission time. The second responding node receives the Pdelay_Req message and records the third reception time. The second responding node packs the third reception time into a PDelay_Resp message and sends it to the second initiating node, and records the fourth transmission time. The second responding node packs the fourth transmission time into a Pdelay_Resp_Follow_Up message and sends it to the second initiating node. The second initiating node receives the PDelay_Resp message and records the fourth reception time.

[0166] At this time, the second initiating node records two timestamps: the third transmission time and the fourth reception time, and obtains the third reception time and the fourth transmission time from the PDelay_Resp message and the Pdelay_Resp_Follow_Up message respectively, so as to calculate the second one-way link delay based on the above 4 timestamps.

[0167] According to an embodiment of the present disclosure, calculating the second one-way link delay according to the third transmission time, the third reception time, the fourth transmission time, and the fourth reception time includes calculating the second one-way link delay D2 according to the following formula: where t5 is the third transmission time, t6 is the third reception time, t7 is the fourth transmission time, t8 is the fourth reception time, t8 - t5 is the second complete link time, and t7 - t6 is the second processing time.

[0168] Similarly, the second initiating node is the second OSU device, and the second responding node is the second communication device; or, the second initiating node is the second communication device, and the second responding node is the second OSU device.

[0169] In step S103, the first OSU device obtains the third one-way link delay of the third communication link when communicating with the second OSU device, including: obtaining an OSU multiplexed frame, and obtaining a delay measurement reference time based on the OSU multiplexed frame, where the OSU multiplexed frame includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiplexed frame carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; the first OSU device obtains the third one-way link delay.

[0170] According to an embodiment of the present disclosure, the OSU multiplexed frame further includes a position identification bit.

[0171] Assume that the OSU multiframe includes 32 OSU frames, and each OSU frame includes a delay measurement bit and a position identification bit. The delay measurement bit and the position identification bit each occupy 1 bit position in the OSU frame. Then the OSU multiframe includes 32 delay measurement bits and 32 position identification bits, and the delay measurement reference time carried by the delay measurement bits included in the OSU multiframe occupies 32 bits.

[0172] Figure 5 A schematic diagram showing a method for obtaining a third one-way link delay DM according to an embodiment of the present disclosure. Figure 6 A schematic diagram showing another method for obtaining a third one-way link delay DM according to an embodiment of the present disclosure. The following takes Figure 5 and Figure 6 two specific embodiments to illustrate the process of obtaining the third one-way link delay DM.

[0173] As Figure 5 shown, in the first specific embodiment:

[0174] The obtaining of the OSU multiframe and the obtaining of the delay measurement reference time based on the OSU multiframe include: the third initiating node on the third communication link periodically sends the OSU multiframe, and uses the delay measurement bits included in the OSU multiframe to carry the OSU sending time; the third response node on the third communication link receives the first OSU multiframe by identifying the position identification bits of the OSU frame, and parses the first OSU multiframe to obtain the corresponding OSU sending time as the delay measurement reference time of the first OSU multiframe.

[0175] According to an embodiment of the present disclosure, the third response node calculates the third one-way link delay according to the delay measurement reference time of the first OSU multiframe and the OSU reception time for receiving the first OSU multiframe.

[0176] Specifically, the third response node subtracts the OSU sending time from the OSU reception time to calculate the third one-way link delay.

[0177] Specifically, the third initiating node periodically sends OSU multiplex frames. The time when the third initiating node sends the OSU multiplex frame is carried in the delay measurement bits of each OSU multiplex frame. The position identification bit of the frame header in each OSU multiplex frame is 1, and the rest of the position identification bits are 0. For example, when the OSU multiplex frame is a 32-frame, the position identification bit of the frame header of the OSU multiplex frame periodically sent by the third initiating node is 1, and the position identification bits of the remaining 31 OSU frames are 0. Therefore, the third responding node can obtain a complete OSU multiplex frame by identifying the position identification bits in the OSU frame, thereby obtaining the OSU transmission time carried in the 32 delay measurement bits in the OSU multiplex frame, and calculating the third one-way link delay based on the reception time of the OSU multiplex frame recorded by the third responding node.

[0178] As Figure 6 shown, in the second specific embodiment:

[0179] The obtaining of the OSU multiplex frame and obtaining the delay measurement reference time based on the OSU multiplex frame includes: the sending end of the third initiating node on the third communication link periodically sends OSU multiplex frames and uses the delay measurement bits included in the OSU multiplex frames to carry serial numbers; the receiving end of the third responding node on the third communication link receives the second OSU multiplex frame by identifying the position identification bits in the OSU frame, parses the second OSU multiplex frame to obtain the corresponding serial number, and sends the serial number corresponding to the second OSU multiplex frame and the receiving time of the responding end to the sending end of the third responding node; the sending end of the third responding node obtains the sending time of the responding end of the third OSU multiplex frame, calculates the residence time of the responding end according to the receiving time of the responding end and the sending time of the responding end, inserts the serial number corresponding to the second OSU multiplex frame and the residence time of the responding end into the delay measurement bits of the third OSU multiplex frame, and sends the third OSU multiplex frame at the sending time of the responding end; the receiving end of the third initiating node parses the third OSU multiplex frame, obtains the serial number corresponding to the second OSU multiplex frame and the residence time of the responding end, and uses the residence time of the responding end as the delay measurement reference time of the second OSU multiplex frame.

[0180] According to an embodiment of the present disclosure, when the sending end of the third initiating node sends the second OSU multiplex frame, a sending end timer is started, and when the receiving end of the third initiating node receives the third OSU multiplex frame, the sending end timer is stopped, and the transceiver link time is obtained based on the sending end timer; the third initiating node calculates the third one-way link delay according to the residence time of the responding end and the transceiver link time.

[0181] Specifically, the third initiating node subtracts the responder residence time from the transceiver link time to obtain a third round-trip link delay, and half of the third round-trip link delay is the third one-way link delay.

[0182] In detail, the transmitting end of the third initiating node periodically sends OSU multiplex frames and starts a transmitting end timer for each transmission cycle. The delay measurement bit in each transmitted OSU multiplex frame carries a corresponding sequence number. The position identification bit in the frame header of each OSU multiplex frame is 1, and the rest of the position identification bits are 0. The receiving end of the third responder node can obtain a complete OSU multiplex frame by identifying the position identification bit in the OSU frame, so as to obtain the sequence number carried in the delay measurement bit in the OSU multiplex frame, record a responder receiving time at the same time, and send the sequence number and the responder receiving time to the transmitting end of the third responder node. The transmitting end of the third responder node obtains the responder sending time, so as to obtain the responder residence time by subtracting the responder receiving time from the responder sending time, and inserts the responder residence time and the sequence number into the delay measurement bit of the OSU multiplex frame and sends it to the receiving end of the third initiating node. The receiving end of the third initiating node then stops the transmitting end timer of this transmission cycle. The time information recorded by the transmitting end timer is the transceiver link time. Furthermore, subtracting the responder residence time from the transceiver link time and then dividing by two is the third one-way link delay.

[0183] The present disclosure does not simply utilize a delay measurement bit of each OSU frame among multiple OSU frames to carry time information, but combines the position identification bits of each OSU frame. Since each OSU frame has a position identification bit and a corresponding delay measurement bit, the present disclosure can automatically identify and parse the position identification field formed by the position identification bits in the OSU multiplex frame. Through this automatic identification process, the specific position of each OSU frame in the OSU multiplex frame can be accurately located, and then the delay measurement field formed by the delay measurement bits of each OSU frame can be automatically extracted from the OSU multiplex frame. This method not only improves the accuracy and efficiency of delay measurement, but also ensures the integrity and reliability of delay information during the entire data transmission process.

[0184] According to an embodiment of the present disclosure, the third initiating node is the first OSU device, and the third responder node is the second OSU device; or, the third initiating node is the second OSU device, and the third responder node is the first OSU device.

[0185] In step S104, the first communication device sends a heterogeneous path delay request message to the second communication device through the optical transmission network. Among them, the first communication device, the first OSU device, and the second OSU device successively accumulate and insert the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of the heterogeneous path delay request message.

[0186] The inventors noticed that in 1588 time synchronization, there are multiple types of PTP (Precision Time Protocol) synchronization messages for realizing time synchronization at different stages. The general format of a PTP message includes: a PTP message encapsulation header (such as Ethernet, IPv4, IPv6, etc.), a general PTP message header, and different PTP message bodies.

[0187] The position of the correction field is in the PTP general message header. Due to the provisions of the IEEE802.1AS standard protocol, it is particularly worth noting that there is a correctionField field in the PTP general message header. However, according to the provisions of the IEEE802.1AS protocol, in most PTP message types, this correction field is not actually enabled, and its value is fixedly set to 0. This situation provides an idea for the inventors, that is, this underutilized field can be used to carry the one-way link delay data accurately measured by the present disclosure technology. This not only makes clever use of the redundant space of the existing protocol, but also ensures the effective recording and transmission of link delay information without disturbing the overall process of the original time synchronization.

[0188] In a specific embodiment, the heterogeneous path delay request message is a Pdelay_Req message.

[0189] The specific process of the above-mentioned first communication device, the first OSU device, and the second OSU device successively accumulating and inserting the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of the heterogeneous path delay request message is as Figure 7 shown:

[0190] 1) The first communication device inserts the first one-way link delay in the correction field of the heterogeneous path delay request message, and then sends the heterogeneous path delay request message inserted with the first one-way link delay to the first OSU device.

[0191] 2) The first OSU device accumulatively inserts the third one-way link delay in the correction field of the heterogeneous path delay request message with the first one-way link delay inserted, and then sends the heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted to the second OSU device.

[0192] 3) The second OSU device accumulatively inserts the second one-way link delay in the correction field of the heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted, and then sends the heterogeneous path delay request message with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay inserted to the second communication device.

[0193] According to an embodiment of the present disclosure, the first OSU device encapsulates the heterogeneous path delay request message with the first one-way link delay inserted according to the OSU protocol, and then accumulatively inserts the third one-way link delay in the correction field of the heterogeneous path delay request message with the first one-way link delay inserted; the second OSU device decapsulates the heterogeneous path delay request message with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay inserted according to the OSU protocol, and then sends it to the second communication device.

[0194] Since the heterogeneous path delay request message (such as a Pdelay_Req message) is a gPTP (generalized Precision Time Protocol) message (a layer-2 message) or a UDP (User Datagram Protocol) message (a layer-3 message) in a time-sensitive network, and both the layer-2 message and the layer-3 message belong to Ethernet messages, when the message arrives at the OSU device, the OSU device needs to perform encapsulation and decapsulation according to the OSU protocol to enable transmission between the first OSU device and the second OSU device.

[0195] In step S105, the second communication device parses the heterogeneous path delay request message, and obtains the total link delay according to the correction field, where the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay.

[0196] Figure 8 Schematic diagram showing obtaining the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network in an embodiment of the present disclosure.

[0197] In step S106, when the second communication device communicates with the first communication device, the second communication device obtains the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay.

[0198] As Figure 8 shown, the first communication device sends a synchronization message to the second communication device, records the master clock timestamp value when sending the synchronization message, then packs the master clock timestamp value into a follow-up message, and sends the follow-up message to the second communication device; the second communication device receives the synchronization message, records the local time when receiving the synchronization message, and parses the follow-up message to obtain the master clock timestamp value.

[0199] Specifically, the first communication device sends a Sync message to the second communication device and records the master clock timestamp value t m of the first time-sensitive network. Then, the master clock timestamp value t m is packed into a Follow_Up message and sent to the second communication device. The second communication device receives the Sync message and records the local time t s of the second time-sensitive network, and parses the Follow_Up message to obtain the master clock timestamp value t m of the first time-sensitive network.

[0200] According to an embodiment of the present disclosure, the second communication device subtracts the master clock timestamp value t s and the total link delay delay from the local time t m to obtain the time deviation from the first communication device.

[0201] Specifically, the time deviation offset is obtained according to the following formula: offset = t s - t m - delay.

[0202] In step S107, the second communication device adjusts the local time based on the time deviation so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0203] According to an embodiment of the present disclosure, the second communication device adds the time deviation to the local time as the adjusted local time.

[0204] In practical applications, since the time deviation between the first communication device and the second communication device in the above cross-OSU heterogeneous communication network has been obtained, the synchronization time between the first communication device and the second communication device within any communication cycle can be adjusted according to this time deviation: t new = t old + offset.

[0205] In a cross-OSU heterogeneous communication network, when the physical link and communication devices remain unchanged, the link delay is basically unchanged, or the average value is very close. Therefore, the present disclosure can also set a calculation cycle, such as 5 s, 10 s, etc., and obtain the time deviation once every calculation cycle to achieve time synchronization between communication devices, or calculate the average value of the time deviations of multiple calculation cycles to achieve time synchronization between communication devices.

[0206] For the delay measurement of the cross-OSU heterogeneous communication network, the present disclosure adopts a more refined and robust measurement strategy. The link delays are measured separately for multiple communication links. Not only the time synchronization message method is used, but also the method of carrying delay measurement information in the delay measurement field of the OSU multiple-frame is adopted. After obtaining multiple link delays through various methods, the correction field in the time synchronization message is used to carry the multiple link delays in a cumulative manner, so that the time-sensitive network at the opposite end can obtain the sum of the link delays to synchronize with the local time-sensitive network, achieving precise time synchronization in the cross-OSU heterogeneous communication network and providing a powerful data transmission and support capability for the distribution communication network.

[0207] Figure 9 FIG. shows a schematic structural diagram of another cross-OSU heterogeneous communication network according to an embodiment of the present disclosure.

[0208] As Figure 9As shown in the figure, a cross-OSU heterogeneous communication network includes: an optical transmission network, a first time-sensitive network and a second time-sensitive network to be synchronized; the first time-sensitive network includes a first communication device, the second time-sensitive network includes a second communication device, the optical transmission network includes a first OSU device and a second OSU device, the first communication device is connected to the first OSU device through a first communication link, the second OSU device is connected to the second communication device through a second communication link, and the first OSU device is connected to the second OSU device through a third communication link; the first communication device sends a heterogeneous path delay request message to the second communication device through the optical transmission network, wherein the first communication device, the first OSU device, and the second OSU device successively accumulate and insert a first one-way link delay, a third one-way link delay, and a second one-way link delay in the correction field of the heterogeneous path delay request message; the second communication device parses the heterogeneous path delay request message and obtains the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay as the total link delay; the second communication device obtains the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network when communicating with the first communication device, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay; the second communication device adjusts the local time based on the time deviation so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0209] According to an embodiment of the present disclosure, the first communication device obtains a first one-way link delay of the first communication link when communicating with the first OSU device; the second OSU device obtains a second one-way link delay of the second communication link when communicating with the second communication device; the first OSU device obtains a third one-way link of the third communication link when communicating with the second OSU device.

[0210] According to an embodiment of the present disclosure, the optical transmission network further includes any one of the following optical transmission devices: a synchronous digital hierarchy (SDH) device, an optical transport network (OTN) device, and a multi-service transport platform (MSTP) device; both ends of the optical transmission device are respectively connected to the first OSU device and the second OSU device.

[0211] Specifically, the first communication device of the first time-sensitive network is connected to the first OSU device through the first communication link. In the optical transmission network, the first OSU device is connected to the second OSU device through the third communication link. An optical transmission device is also provided on the third communication link to adapt and perform high-speed and large-capacity transmission on various services carried by the OSU device to ensure the smooth transmission of services. The second OSU device of the second time-sensitive network is connected to the second communication device through the second communication link.

[0212] Figure 10 FIG. shows a flowchart of a method for an OSU device according to an embodiment of the present disclosure. The OSU device is the first OSU device in the optical transmission network. The first OSU device is connected to the first communication device in the first time-sensitive network through the first communication link. The first OSU device is connected to the second OSU device in the optical transmission network through the third communication link. The second OSU device is connected to the second communication device in the second time-sensitive network through the second communication link. As Figure 10 shown, the method includes steps S1001 to S1003.

[0213] In step S1001, obtaining the third one-way link delay of the third communication link when communicating with the second OSU device includes: obtaining an OSU multiplex frame, and obtaining a delay measurement reference time based on the OSU multiplex frame, where the OSU multiplex frame includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiplex frame carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; obtaining the third one-way link delay.

[0214] In step S1002, receiving, from the first communication device, a heterogeneous path delay request message inserted with a first one-way link delay, where the heterogeneous path delay request message inserted with the first one-way link delay is obtained by the first communication device inserting the first one-way link delay in the correction field of the heterogeneous path delay request message.

[0215] In step S1003, the third one-way link delay is cumulatively inserted into the correction field of the heterogeneous path delay request message with the first one-way link delay inserted, and then the heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted is sent to the second OSU device. Wherein, the second OSU device cumulatively inserts the second one-way link delay into the correction field of the heterogeneous path delay request message with the sum of the first one-way link delay and the third one-way link delay inserted, and then sends the heterogeneous path delay request message with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay inserted to the second communication device. The second communication device obtains the total link delay according to the correction field and calculates the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network.

[0216] In the present disclosure, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay. The first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device, and the second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device.

[0217] In the present disclosure, the first OSU device obtains the third one-way link delay, so that when subsequently receiving a heterogeneous path delay request message with the first one-way link delay inserted sent by the first communication device, the third one-way link delay is cumulatively inserted into the correction field of the heterogeneous path delay request message. That is, after the first OSU device inserts the sum of the first one-way link delay and the third one-way link delay into the correction field, it is sent to the second OSU device, which facilitates the subsequent operation of the second OSU device.

[0218] Figure 11 The flowchart of another method for an OSU device according to an embodiment of the present disclosure is shown. The OSU device is the second OSU device in the optical transport network. The second OSU device is connected to the second communication device in the second time-sensitive network through a second communication link, and the second OSU device is connected to the first OSU device in the optical transport network through a third communication link. The first OSU device is connected to the first communication device in the first time-sensitive network through a first communication link. As Figure 11 shown, the method includes steps S1101 to S1103.

[0219] In step S1101, the second one-way link delay of the second communication link is obtained when communicating with the second communication device.

[0220] In step S1102, a heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay is received from the first OSU device. The heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay is obtained by successively accumulating and inserting in the correction field of the heterogeneous path delay request message by the first communication device and the first OSU device.

[0221] In step S1103, the second one-way link delay is accumulated and inserted in the correction field of the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, and then the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay is sent to the second communication device, so that the second communication device can obtain the total link delay according to the correction field and calculate the time deviation from the first communication device according to the total link delay, so as to realize the time synchronization between the second time-sensitive network and the first time-sensitive network.

[0222] In the present disclosure, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay. The first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device. The third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0223] In the present disclosure, the second OSU device obtains the second one-way link delay, so that when subsequently receiving a heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay sent by the first OSU device, the second one-way link delay is continuously accumulated and inserted in the correction field of the heterogeneous path delay request message. That is, after the second OSU device inserts the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field, it is sent to the second communication device, so that the second communication device can conveniently calculate the delay from the first communication device according to the sum of the one-way link delays (total link delay).

[0224] Figure 12A flowchart showing a method for a communication device according to an embodiment of the present disclosure. The communication device is a first communication device in a first time-sensitive network. The first communication device is connected to a first OSU device in an optical transport network through a first communication link. The first OSU device is connected to a second OSU device in the optical transport network through a third communication link. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link. As Figure 12 shown, the method includes steps S1201 to S1202.

[0225] In step S1201, obtain a first one-way link delay of the first communication link when communicating with the first OSU device.

[0226] In step S1202, insert the first one-way link delay into a correction field of the heterogeneous path delay request message, and then send the heterogeneous path delay request message inserted with the first one-way link delay to the first OSU device. Wherein, after the first OSU device and the second OSU device successively accumulate and insert a third one-way link delay and a second one-way link delay into the correction field of the heterogeneous path delay request message inserted with the first one-way link delay, the second OSU device sends the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device; the second communication device obtains the total link delay according to the correction field and calculates the time deviation from the first communication device according to the total link delay to achieve time synchronization between the second time-sensitive network and the first time-sensitive network.

[0227] In the present disclosure, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay. The second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device. The third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0228] Figure 13 A flowchart showing another method for a communication device according to an embodiment of the present disclosure. The communication device is a second communication device in a second time-sensitive network. The second communication device is connected to a second OSU device in the optical transport network through a second communication link. The second OSU device is connected to a first OSU device through a third communication link. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link. As Figure 13As shown, the method includes steps S1301 to S1304.

[0229] In step S1301, a heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay is obtained from a second OSU device. The heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay is obtained by successively accumulating and inserting the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction domain field of the heterogeneous path delay request message by the first communication device, the first OSU device, and the second OSU device.

[0230] In step S1302, the total link delay is obtained according to the correction domain field of the heterogeneous path delay request message. The total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay.

[0231] In step S1303, when communicating with the first communication device, the main clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network are obtained, and the time deviation from the first communication device is calculated according to the main clock timestamp value, the local time, and the total link delay.

[0232] In step S1304, the local time is adjusted based on the time deviation so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0233] The present disclosure realizes precise time synchronization in a cross-OSU heterogeneous communication network, providing a powerful data transmission and support capability for a power distribution communication network.

[0234] Figure 14 The structural block diagram of a device for an OSU device according to an embodiment of the present disclosure is shown. The device 1400 includes: a first acquisition module 1401, a first reception module 1402, and a first transmission module 1403.

[0235] In the present disclosure, the OSU device is the first OSU device in an optical transmission network. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link. The first OSU device is connected to a second OSU device in the optical transmission network through a third communication link. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link.

[0236] The first obtaining module 1401 is configured to obtain a third one-way link delay of the third communication link when communicating with the second OSU device, including: obtaining an OSU multiplex frame, and obtaining a delay measurement reference time based on the OSU multiplex frame, where the OSU multiplex frame includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiplex frame carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; and obtaining the third one-way link delay.

[0237] The first receiving module 1402 is configured to receive, from the first communication device, a heterogeneous path delay request message inserted with a first one-way link delay, where the heterogeneous path delay request message inserted with the first one-way link delay is obtained by the first communication device inserting the first one-way link delay into a correction field of the heterogeneous path delay request message.

[0238] The first sending module 1403 is configured to accumulate and insert the third one-way link delay into a correction field of the heterogeneous path delay request message inserted with the first one-way link delay, and then send the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay to the second OSU device, where the second OSU device accumulates and inserts a second one-way link delay into the correction field of the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, and then sends the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device, and the second communication device obtains a total link delay according to the correction field and calculates a time deviation from the first communication device according to the total link delay, so as to implement time synchronization between the second time-sensitive network and the first time-sensitive network.

[0239] Wherein, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay, the first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device, and the second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device.

[0240] Figure 15 The structural block diagram of another device for an OSU device according to an embodiment of the present disclosure is shown. The device 1500 includes: a second obtaining module 1501, a second receiving module 1502, and a second sending module 1503.

[0241] In the present disclosure, the OSU device is the second OSU device in an optical transport network. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link. The second OSU device is connected to a first OSU device in the optical transport network through a third communication link. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link.

[0242] The second obtaining module 1501 is configured to obtain a second one-way link delay of the second communication link when communicating with the second communication device.

[0243] The second receiving module 1502 is configured to receive, from the first OSU device, a heterogeneous path delay request message inserted with the sum of a first one-way link delay and a third one-way link delay. The heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay is obtained by successively accumulating and inserting in a correction field of the heterogeneous path delay request message by the first communication device and the first OSU device.

[0244] The second sending module 1502 is configured to accumulate and insert the second one-way link delay in the correction field of the heterogeneous path delay request message inserted with the sum of the first one-way link delay and the third one-way link delay, and then send the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay to the second communication device, so that the second communication device can obtain a total link delay according to the correction field and calculate a time deviation from the first communication device according to the total link delay, so as to realize time synchronization between the second time-sensitive network and the first time-sensitive network.

[0245] Wherein, the total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay. The first one-way link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device. The third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0246] Figure 16 A structural block diagram of a device for a communication device according to an embodiment of the present disclosure is shown. The device 1600 includes: a third obtaining module 1601 and a third sending module 1602.

[0247] In the present disclosure, the communication device is a first communication device in a first time-sensitive network. The first communication device is connected to a first OSU device in an optical transport network through a first communication link. The first OSU device is connected to a second OSU device in the optical transport network through a third communication link. The second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link.

[0248] The third obtaining module 1601 is configured to obtain a first one-way link delay of the first communication link when communicating with the first OSU device.

[0249] The third sending module 1602 is configured to insert the first one-way link delay into a correction field of the heterogeneous path delay request message, and then send the heterogeneous path delay request message inserted with the first one-way link delay to the first OSU device. Wherein, after the first OSU device and the second OSU device successively accumulate and insert a third one-way link delay and a second one-way link delay into the correction field of the heterogeneous path delay request message inserted with the first one-way link delay, the second OSU device sends the heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay to the second communication device; the second communication device obtains a total link delay according to the correction field, and calculates a time deviation from the first communication device according to the total link delay, so as to realize time synchronization between the second time-sensitive network and the first time-sensitive network.

[0250] Wherein, the total link delay is the sum of the first one-way link delay, the third one-way link delay and the second one-way link delay. The second one-way link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device. The third one-way link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device.

[0251] Figure 17 FIG. shows a structural block diagram of another device for a communication device according to an embodiment of the present disclosure. The device 1700 includes: a fourth obtaining module 1701, a fifth obtaining module 1702, a calculation module 1703 and an adjustment module 1704.

[0252] In the present disclosure, the communication device is a second communication device in a second time-sensitive network. The second communication device is connected to a second OSU device in the optical transport network through a second communication link. The second OSU device is connected to a first OSU device through a third communication link. The first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link.

[0253] The fourth acquisition module 1701 is configured to acquire a heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay from a second OSU device. The heterogeneous path delay request message inserted with the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay is obtained by successively accumulating and inserting the first one-way link delay, the third one-way link delay, and the second one-way link delay in the correction field of the heterogeneous path delay request message by the first communication device, the first OSU device, and the second OSU device.

[0254] The fifth acquisition module 1702 is configured to acquire a total link delay according to the correction field of the heterogeneous path delay request message. The total link delay is the sum of the first one-way link delay, the third one-way link delay, and the second one-way link delay;

[0255] The calculation module 1703 is configured to acquire the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network when communicating with the first communication device, and calculate the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay.

[0256] The adjustment module 1704 is configured to adjust the local time based on the time deviation so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0257] The present disclosure also discloses an electronic device, Figure 18 showing a structural block diagram of an electronic device according to an embodiment of the present disclosure.

[0258] As Figure 18 shown, the electronic device includes a memory and a processor. Among them, the memory is used to store computer instructions, and the computer instructions are executed by the processor to implement the method according to the embodiment of the present disclosure.

[0259] Among them, the first time-sensitive network includes a first communication device, the second time-sensitive network includes a second communication device, the optical transmission network includes a first OSU device and a second OSU device. The first communication device is connected to the first OSU device through a first communication link, the second OSU device is connected to the second communication device through a second communication link, and the first OSU device is connected to the second OSU device through a third communication link.

[0260] The method includes:

[0261] According to an embodiment of the present disclosure, the first OSU device obtains a third one-way link delay of the third communication link when communicating with the second OSU device, including: obtaining an OSU multiplexed frame, and obtaining a delay measurement reference time based on the OSU multiplexed frame, where the OSU multiplexed frame includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiplexed frame carries the delay measurement reference time; calculating the third one-way link delay according to the delay measurement reference time; obtaining the third one-way link delay; receiving a heterogeneous path delay request message from the first communication device, and inserting the third one-way link delay into the correction field of the heterogeneous path delay request message and then sending it to the second OSU device.

[0262] According to an embodiment of the present disclosure, the second OSU device obtains a second one-way link delay of the second communication link when communicating with the second communication device; receives a heterogeneous path delay request message from the first OSU device, and inserts the second one-way link delay into the correction field of the heterogeneous path delay request message and then sends it to the second communication device.

[0263] According to an embodiment of the present disclosure, the first communication device obtains a first one-way link delay of the first communication link when communicating with the first OSU device; inserts the first one-way link delay into the correction field of the heterogeneous path delay request message and then sends it to the first OSU device.

[0264] According to an embodiment of the present disclosure, the second communication device obtains a heterogeneous path delay request message inserted with a total link delay from the second OSU device, parses the heterogeneous path delay request message to obtain the total link delay; obtains the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network when communicating with the first communication device, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time, and the total link delay; adjusts the local time based on the time deviation so that the second time-sensitive network is time-synchronized with the first time-sensitive network.

[0265] Figure 19 The structural schematic diagram of a computer system suitable for implementing the method according to an embodiment of the present disclosure is shown.

[0266] As Figure 19As shown, the computer system includes a processing unit, which can execute various methods in the above embodiments according to a program stored in a read-only memory (ROM) or a program loaded from a storage section into a random access memory (RAM). In the RAM, various programs and data required for the operation of the computer system are also stored. The processing unit, ROM, and RAM are connected to each other via a bus. An input / output (I / O) interface is also connected to the bus.

[0267] The following components are connected to the I / O interface: an input section including a keyboard, a mouse, etc.; an output section including, for example, a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage section including a hard disk, etc.; and a communication section including a network interface card such as a LAN card, a modem, etc. The communication section performs a communication process via a network such as the Internet. A drive is also connected to the I / O interface as needed. A removable medium, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive as needed so that a computer program read from it can be installed into the storage section as needed. Among them, the processing unit can be implemented as a processing unit such as a CPU, a GPU, a TPU, an FPGA, an NPU, etc.

[0268] In particular, according to an embodiment of the present disclosure, the method described above can be implemented as a computer software program. For example, an embodiment of the present disclosure includes a computer program product, which includes a computer program tangibly embodied on a machine-readable medium, and the computer program includes program code for executing the above method. In such an embodiment, the computer program can be downloaded and installed from a network through the communication section, and / or installed from a removable medium.

[0269] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagram may represent a module, a program segment, or a part of code, and the module, program segment, or part of code includes one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order from that marked in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagram and / or flowchart, and the combination of blocks in the block diagram and / or flowchart, can be implemented by a dedicated hardware-based system for performing the specified functions or operations, or can be implemented by a combination of dedicated hardware and computer instructions.

[0270] The units or modules involved in the embodiments described in this disclosure can be implemented in software or in programmable hardware. The described units or modules can also be provided in a processor, and the names of these units or modules do not, in some cases, constitute a limitation on the units or modules themselves.

[0271] As another aspect, this disclosure also provides a computer-readable storage medium. The computer-readable storage medium can be the computer-readable storage medium included in the electronic device or computer system in the above embodiments; it can also exist independently and be a computer-readable storage medium not assembled into the device. The computer-readable storage medium stores one or more programs, and the one or more programs are used by one or more processors to execute the methods described in this disclosure.

[0272] The above description is only a preferred embodiment of this disclosure and an explanation of the technical principles applied. Those skilled in the art should understand that the scope of the invention involved in this disclosure is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the inventive concept. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) having similar functions disclosed in this disclosure.

Claims

1. A time synchronization method for a time-sensitive network in a heterogeneous communication network across optical service units (OSUs), characterized in that: The cross-OSU heterogeneous communication network includes: an optical transmission network, a first time-sensitive network to be synchronized, and a second time-sensitive network, the first time-sensitive network includes a first communication device, the second time-sensitive network includes a second communication device, the optical transmission network includes a first OSU device and a second OSU device, the first communication device is connected to the first OSU device through a first communication link, the second OSU device is connected to the second communication device through a second communication link, and the first OSU device is connected to the second OSU device through a third communication link. The method includes: The first communication device acquires a first unidirectional link delay of the first communication link when communicating with the first OSU device; The second OSU device acquires a second unidirectional link delay of the second communication link when communicating with the second communication device; The first OSU device obtains the third unidirectional link delay of the third communication link when communicating with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay; The first communication device sends a heterogeneous path delay request message to the second communication device through the optical transmission network, wherein the first communication device, the first OSU device, and the second OSU device cumulatively insert the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay in the correction domain field of the heterogeneous path delay request message step by step; The second communication device parses the heterogeneous path delay request message, and acquires a total link delay according to the correction domain field, where the total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay; The second communication device obtains the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network when communicating with the first communication device, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time and the total link delay; The second communication device adjusts the local time based on the time offset so that the second time-sensitive network is synchronized with the time of the first time-sensitive network.

2. The method according to claim 1, characterized in that The first communication device acquires a first unidirectional link delay of the first communication link when communicating with the first OSU device, including: The first initiating node on the first communication link sends a first path delay request message to the first responding node on the first communication link, and receives a first path delay response message and a first path delay response follow-up message replied by the first responding node; The first initiating node records a first sending time of the first path delay request message and a second receiving time of the first path delay response message, obtains the first receiving time of the first path delay request message from the first path delay response message, and obtains the second sending time of the first path delay request message from the first path delay response follow-up message, thereby calculating the first unidirectional link delay according to the first sending time, the first receiving time, the second sending time, and the second receiving time; The first communication device obtains the first unidirectional link delay.

3. The method according to claim 2, characterized in that The calculating the first unidirectional link delay according to the first sending time, the first receiving time, the second sending time, and the second receiving time includes: Calculate a first complete link time of sending and receiving a message by the first initiating node according to the second receiving time and the first sending time; Calculate a first processing time for the first response node to process the message according to the first receiving time and the second sending time; Subtracting the first processing time from the first complete link time to obtain a first bidirectional link delay of the first communication link; Half of the first bidirectional link delay is the first unidirectional link delay.

4. The method according to claim 1, characterized in that: The second OSU device acquires a second unidirectional link delay of the second communication link when communicating with the second communication device, including: The second initiating node on the second communication link sends a second path delay request message to the second responding node on the second communication link, and receives a second path delay response message and a second path delay response follow-up message replied by the second responding node; The second initiating node records the third sending time of the second path delay request message and the fourth receiving time of the second path delay response message, obtains the third receiving time of the second path delay request message from the second path delay response message, and obtains the fourth sending time of the second path delay request message from the second path delay response follow-up message, thereby calculating the second unidirectional link delay according to the third sending time, the third receiving time, the fourth sending time, and the fourth receiving time; The second OSU device obtains the second unidirectional link delay.

5. The method according to claim 4, characterized in that The calculating the second unidirectional link delay according to the third sending time, the third receiving time, the fourth sending time, and the fourth receiving time includes: Calculate a second complete link time for the second initiating node to send and receive a message according to the fourth receiving time and the third sending time; Calculate a second processing time for the second response node to process the message according to the third receiving time and the fourth sending time; Subtracting the second processing time from the second complete link time to obtain a second bidirectional link delay of the second communication link; Half of the second bidirectional link delay is the second unidirectional link delay.

6. The method according to claim 1, characterized in that: The OSU frame also includes a position identification bit; The obtaining of the OSU multiframe and obtaining the delay measurement reference time based on the OSU multiframe include: the third initiating node on the third communication link periodically sends the OSU multiframe, and uses the delay measurement bit included in the OSU multiframe to carry the OSU sending time; the third responding node on the third communication link receives the first OSU multiframe by identifying the position identification bit of the OSU frame, and parses the first OSU multiframe to obtain the corresponding OSU sending time as the delay measurement reference time of the first OSU multiframe; The calculating the third unidirectional link delay according to the delay measurement reference time includes: the third response node calculating the third unidirectional link delay according to the delay measurement reference time of the first OSU multiframe and the OSU receiving time of receiving the first OSU multiframe.

7. The method according to claim 6, characterized in that The third response node subtracts the OSU sending time from the OSU receiving time to calculate the third unidirectional link delay.

8. The method according to claim 1, characterized in that: The OSU frame also includes a position identification bit; The obtaining of the OSU multiframe and obtaining the delay measurement reference time based on the OSU multiframe include: The transmitting end of the third initiating node on the third communication link periodically sends an OSU multiframe, and uses the delay measurement bit included in the OSU multiframe to carry the sequence number; The receiving end of the third response node on the third communication link receives the second OSU multiframe by identifying the position identification bit in the OSU frame, parses the second OSU multiframe to obtain the corresponding sequence number, and sends the sequence number corresponding to the second OSU multiframe and the response end reception time to the sending end of the third response node; The transmitting end of the third response node obtains the responding end sending time of the third OSU multiframe, calculates the responding end residence time according to the responding end receiving time and the responding end sending time, inserts the sequence number corresponding to the second OSU multiframe and the responding end residence time into the delay measurement bit of the third OSU multiframe, and sends the third OSU multiframe at the responding end sending time; The receiving end of the third initiating node parses the third OSU multiframe, obtains the sequence number and the responder residence time corresponding to the second OSU multiframe, and uses the responder residence time as a delay measurement reference time of the second OSU multiframe.

9. The method according to claim 8, characterized in that The calculating the third unidirectional link delay according to the delay measurement reference time includes: When the transmitting end of the third initiating node sends the second OSU multiframe, start the transmitting end timer, when the receiving end of the third initiating node receives the third OSU multiframe, stop the transmitting end timer, and obtain the transmitting and receiving link time based on the transmitting end timer; The third initiating node calculates the third unidirectional link delay according to the responder residence time and the transceiver link time.

10. The method according to claim 9, characterized in that The third initiating node subtracts the responder residence time from the transceiver link time to obtain a third bidirectional link delay, and half of the third bidirectional link delay is the third unidirectional link delay.

11. The method according to claim 1, characterized in that: The first communication device, the first OSU device, and the second OSU device cumulatively insert the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay in the correction domain field of the heterogeneous path delay request message step by step, including: The first communication device inserts the first unidirectional link delay into the correction domain field of the heterogeneous path delay request message, and then sends the heterogeneous path delay request message into which the first unidirectional link delay is inserted to the first OSU device; The first OSU device cumulatively inserts the third unidirectional link delay in the correction domain field of the heterogeneous path delay request message into which the first unidirectional link delay is inserted, and then sends the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted to the second OSU device; The second OSU device cumulatively inserts the second unidirectional link delay in the correction domain field of the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted, and then sends the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted to the second communication device.

12. The method according to claim 11, characterized in that: The first OSU device encapsulates the heterogeneous path delay request message into which the first unidirectional link delay is inserted according to the OSU protocol, and then cumulatively inserts the third unidirectional link delay into the correction domain field of the heterogeneous path delay request message into which the first unidirectional link delay is inserted; The second OSU device decapsulates the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted according to the OSU protocol, and then sends it to the second communication device.

13. The method according to claim 1, characterized in that The second communication device acquires the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network when communicating with the first communication device, including: The first communication device sends a synchronization message to the second communication device, records the timestamp value of the master clock for sending the synchronization message, then packs the timestamp value of the master clock into a follow-up message, and sends the follow-up message to the second communication device; The second communication device receives the synchronization message, records the local time of receiving the synchronization message, and parses the follow-up message to obtain the timestamp value of the master clock.

14. The method according to claim 13, characterized in that The second communication device calculates the time deviation with the first communication device according to the timestamp value of the master clock, the local time and the total link delay, including: The second communication device subtracts the master clock timestamp value and the total link delay from the local time to obtain a time deviation from the first communication device.

15. The method according to claim 14, characterized in that The second communication device adjusts the local time based on the time offset, including: the second communication device adds the time offset to the local time as the adjusted local time.

16. An inter-OSU heterogeneous communication network, characterized in that: include: An optical transmission network, a first time-sensitive network to be synchronized, and a second time-sensitive network; The first time-sensitive network includes a first communication device, the second time-sensitive network includes a second communication device, the optical transmission network includes a first OSU device and a second OSU device, the first communication device is connected to the first OSU device via a first communication link, the second OSU device is connected to the second communication device via a second communication link, and the first OSU device is connected to the second OSU device via a third communication link; The first OSU device obtains the third unidirectional link delay of the third communication link when communicating with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay; The first communication device sends a heterogeneous path delay request message to the second communication device through the optical transmission network, wherein the first communication device, the first OSU device, and the second OSU device cumulatively insert the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay in the correction domain field of the heterogeneous path delay request message step by step; the second communication device parses the heterogeneous path delay request message, and obtains the total link delay according to the correction domain field, and the total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay; The second communication device obtains the master clock timestamp value of the first time-sensitive network and the local time of the second time-sensitive network when communicating with the first communication device, and calculates the time deviation from the first communication device according to the master clock timestamp value, the local time and the total link delay; The second communication device adjusts the local time based on the time offset so that the second time-sensitive network is synchronized with the time of the first time-sensitive network.

17. The communication network according to claim 16, characterized in that: The first communication device acquires a first unidirectional link delay of the first communication link when communicating with the first OSU device; The second OSU device obtains a second unidirectional link delay of the second communication link when communicating with the second communication device.

18. A method for an OSU device, characterized in that: The OSU device is a first OSU device in an optical transmission network, the first OSU device is connected to a first communication device in a first time-sensitive network via a first communication link, the first OSU device is connected to a second OSU device in the optical transmission network via a third communication link, and the second OSU device is connected to a second communication device in a second time-sensitive network via a second communication link, and the method includes: Obtaining a third unidirectional link delay of the third communication link when communicating with the second OSU device, comprising: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; and obtaining the third unidirectional link delay; receiving, from the first communication device, a heterogeneous path delay request message into which a first unidirectional link delay is inserted, wherein the heterogeneous path delay request message into which the first unidirectional link delay is inserted is obtained by the first communication device inserting the first unidirectional link delay into a correction domain field of the heterogeneous path delay request message; Accumulatively inserting the third unidirectional link delay into the correction domain field of the heterogeneous path delay request message into which the first unidirectional link delay is inserted, and then sending the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted to the second OSU device, wherein the second OSU device cumulatively inserts the second unidirectional link delay into the correction domain field of the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted, and then sending the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted to the second communication device, the second communication device acquires the total link delay according to the correction domain field, and calculates the time deviation with the first communication device according to the total link delay, so as to achieve time synchronization between the second time-sensitive network and the first time-sensitive network; Among them, the total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay. The first unidirectional link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device, and the second unidirectional link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device.

19. A method for an OSU device, characterized in that: The OSU device is a second OSU device in the optical transmission network, the second OSU device is connected to a second communication device in a second time-sensitive network via a second communication link, the second OSU device is connected to a first OSU device in the optical transmission network via a third communication link, and the first OSU device is connected to a first communication device in a first time-sensitive network via a first communication link, and the method includes: Acquire a second unidirectional link delay of a second communication link when communicating with the second communication device; receiving, from the first OSU device, a heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted, wherein the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is obtained by accumulating and inserting step by step in the correction domain field of the heterogeneous path delay request message by the first communication device and the first OSU device; Accumulatively inserting the second unidirectional link delay into the correction domain field of the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted, and then sending the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted to the second communication device, so that the second communication device can obtain the total link delay according to the correction domain field, and calculate the time deviation with the first communication device according to the total link delay, so as to achieve time synchronization between the second time-sensitive network and the first time-sensitive network; The total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay, and the first unidirectional link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device; The third unidirectional link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay.

20. A method for a communication device, characterized in that: The communication device is a first communication device in a first time-sensitive network, the first communication device is connected to a first OSU device in an optical transmission network through a first communication link, the first OSU device is connected to a second OSU device in the optical transmission network through a third communication link, and the second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link, and the method includes: Acquire a first unidirectional link delay of the first communication link when communicating with the first OSU device; Insert the first unidirectional link delay into the correction domain field of the heterogeneous path delay request message, and then send the heterogeneous path delay request message into which the first unidirectional link delay is inserted to the first OSU device, wherein the first OSU device and the second OSU device cumulatively insert the third unidirectional link delay and the second unidirectional link delay into the correction domain field of the heterogeneous path delay request message into which the first unidirectional link delay is inserted step by step, and then the second OSU device sends the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted to the second communication device; the second communication device obtains the total link delay according to the correction domain field, and calculates the time deviation with the first communication device according to the total link delay, so as to achieve time synchronization between the second time-sensitive network and the first time-sensitive network; The total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay, and the second unidirectional link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device; The third unidirectional link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay.

21. A method for a communication device, characterized in that: The communication device is a second communication device in a second time-sensitive network, the second communication device is connected to a second OSU device in an optical transmission network via a second communication link, the second OSU device is connected to a first OSU device via a third communication link, and the first OSU device is connected to a first communication device in a first time-sensitive network via a first communication link, and the method includes: Acquire a heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted from the second OSU device, wherein the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is obtained by the first communication device, the first OSU device and the second OSU device cumulatively inserting the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay in the correction domain field of the heterogeneous path delay request message step by step; The third unidirectional link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay; Acquire a total link delay according to a correction domain field of the heterogeneous path delay request message, where the total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay; Acquire a master clock timestamp value of the first time-sensitive network and a local time of the second time-sensitive network when communicating with the first communication device, and calculate a time deviation from the first communication device based on the master clock timestamp value, the local time, and the total link delay; The local time is adjusted based on the time deviation so that the second time-sensitive network is synchronized with the time of the first time-sensitive network.

22. A device for an OSU device, characterized in that: The OSU device is a first OSU device in an optical transmission network, the first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link, the first OSU device is connected to a second OSU device in the optical transmission network through a third communication link, and the second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link, and the apparatus includes: The first acquisition module is configured to acquire the third unidirectional link delay of the third communication link when communicating with the second OSU device, including: acquiring an OSU multiframe, and acquiring a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; and acquiring the third unidirectional link delay; A first receiving module is configured to receive a heterogeneous path delay request message into which a first unidirectional link delay is inserted from the first communication device, wherein the heterogeneous path delay request message into which the first unidirectional link delay is inserted is obtained by the first communication device inserting the first unidirectional link delay into a correction domain field of the heterogeneous path delay request message; A first sending module is configured to cumulatively insert the third unidirectional link delay in the correction domain field of the heterogeneous path delay request message into which the first unidirectional link delay is inserted, and then send the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted to a second OSU device, wherein the second OSU device cumulatively inserts the second unidirectional link delay in the correction domain field of the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted, and then send the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted to the second communication device, the second communication device acquires the total link delay according to the correction domain field, and calculates the time deviation with the first communication device according to the total link delay, so as to achieve time synchronization between the second time-sensitive network and the first time-sensitive network; Among them, the total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay. The first unidirectional link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device, and the second unidirectional link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device.

23. A device for an OSU device, characterized in that: The OSU device is a second OSU device in the optical transmission network, the second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link, the second OSU device is connected to a first OSU device in the optical transmission network through a third communication link, and the first OSU device is connected to a first communication device in a first time-sensitive network through a first communication link, and the apparatus includes: A second acquisition module is configured to acquire a second unidirectional link delay of a second communication link when communicating with the second communication device; A second receiving module is configured to receive, from the first OSU device, a heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted, wherein the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is obtained by accumulating and inserting step by step in a correction domain field of the heterogeneous path delay request message by the first communication device and the first OSU device; a second sending module, configured to cumulatively insert the second unidirectional link delay into the correction domain field of the heterogeneous path delay request message into which the sum of the first unidirectional link delay and the third unidirectional link delay is inserted, and then send the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted to the second communication device, so that the second communication device can obtain the total link delay according to the correction domain field, and calculate the time deviation with the first communication device according to the total link delay, so as to achieve time synchronization between the second time-sensitive network and the first time-sensitive network; The total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay, and the first unidirectional link delay is the delay of the first communication link obtained when the first communication device communicates with the first OSU device; The third unidirectional link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay.

24. An apparatus for a communication device, characterized in that: The communication device is a first communication device in a first time-sensitive network, the first communication device is connected to a first OSU device in an optical transmission network through a first communication link, the first OSU device is connected to a second OSU device in the optical transmission network through a third communication link, and the second OSU device is connected to a second communication device in a second time-sensitive network through a second communication link, and the apparatus includes: A third acquisition module is configured to acquire a first unidirectional link delay of the first communication link when communicating with the first OSU device; The third sending module is configured to insert the first unidirectional link delay into the correction domain field of the heterogeneous path delay request message, and then send the heterogeneous path delay request message into which the first unidirectional link delay is inserted to the first OSU device, wherein the first OSU device and the second OSU device cumulatively insert the third unidirectional link delay and the second unidirectional link delay into the correction domain field of the heterogeneous path delay request message into which the first unidirectional link delay is inserted step by step, and then the second OSU device sends the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay and the second unidirectional link delay is inserted to the second communication device; the second communication device obtains the total link delay according to the correction domain field, and calculates the time deviation with the first communication device according to the total link delay, so as to achieve time synchronization between the second time-sensitive network and the first time-sensitive network; The total link delay is the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay, and the second unidirectional link delay is the delay of the second communication link obtained when the second OSU device communicates with the second communication device; The third unidirectional link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay.

25. An apparatus for a communication device, characterized in that: The communication device is a second communication device in a second time-sensitive network, the second communication device is connected to a second OSU device in an optical transmission network via a second communication link, the second OSU device is connected to a first OSU device via a third communication link, and the first OSU device is connected to a first communication device in a first time-sensitive network via a first communication link, and the apparatus includes: a fourth acquisition module, configured to acquire, from the second OSU device, a heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay is inserted, wherein the heterogeneous path delay request message into which the sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay is obtained by the first communication device, the first OSU device, and the second OSU device cumulatively inserting the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay in a correction domain field of the heterogeneous path delay request message step by step; The third unidirectional link delay is the delay of the third communication link obtained when the first OSU device communicates with the second OSU device, including: obtaining an OSU multiframe, and obtaining a delay measurement reference time based on the OSU multiframe, wherein the OSU multiframe includes a specified number of OSU frames, the OSU frame includes a delay measurement bit, and the delay measurement bit included in the OSU multiframe carries the delay measurement reference time; calculating the third unidirectional link delay according to the delay measurement reference time; the first OSU device obtains the third unidirectional link delay; a fifth acquisition module, configured to acquire a total link delay according to a correction domain field of the heterogeneous path delay request message, wherein the total link delay is a sum of the first unidirectional link delay, the third unidirectional link delay, and the second unidirectional link delay; a calculation module, configured to obtain a master clock timestamp value of the first time-sensitive network and a local time of the second time-sensitive network when communicating with the first communication device, and calculate a time deviation from the first communication device based on the master clock timestamp value, the local time and the total link delay; The adjustment module is configured to adjust the local time based on the time deviation so that the second time-sensitive network is synchronized with the time of the first time-sensitive network.

26. An electronic device, characterized in that: It comprises a memory and a processor; wherein the memory is used to store computer instructions, wherein the computer instructions are executed by the processor to implement the method according to any one of claims 18 to 21.

27. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed by a processor, the method described in any one of claims 18 to 21 is implemented.

28. A computer program product, comprising computer instructions, which, when executed by a processor, implement the method according to any one of claims 18 to 21.

Images