Time synchronization accuracy self-monitoring method for time sensitive network, time sensing system and self-monitoring system

Abstract

The invention provides a time synchronization accuracy self-monitoring method for a time sensitive network, a time sensing system and a self-monitoring system. The synchronization messages and the following messages uniquely corresponding to the synchronization messages are sequentially sent by a previous node in a time synchronization information transmission path where the time sensing system is located, and the previous node is a preset master clock node or other time sensing systems; and acquiring a local clock offset value based on the synchronization message, the following message and the propagation time delay between the local clock offset value and the previous node, performing time synchronization accuracy self-monitoring on the local clock offset value, and if the local clock offset value is monitored to meet a time synchronization accuracy rule, sending the time synchronization accuracy rule to the next node. And if so, calibrating the local clock based on the local clock offset value. According to the invention, the accuracy of the received time synchronization message can be monitored in real time on the time sensing system, and the accuracy of time synchronization in the time-sensitive network can be ensured.

Description

Technical Field

[0001] The present application relates to the field of network communication technology, and in particular to a time synchronization accuracy self-monitoring method, a time perception system and a self-monitoring system for a time-sensitive network. Background Art

[0002] The IEEE 802.1AS protocol defines that when the best master clock fails, the problem can be solved by reselecting a new best master clock, but this process is not instantaneous, and some time-aware systems may cause time jumps. Therefore, improvements have been made in subsequent versions of the IEEE 802.1AS protocol to achieve seamless low-latency fault recovery by configuring multiple best master clock sources and multiple time synchronization spanning trees.

[0003] At present, the time synchronization protocol IEEE802.1AS of the Time Sensitive Networking (TSN) only considers the redundancy of the master clock or topology redundancy in terms of reliability, and does not consider the situation where the clock information in the time synchronization message received by the time-aware system is inaccurate. The upstream time-aware system may generate messages with inaccurate synchronization information due to equipment failure or other human interference factors. The downstream time-aware system only blindly follows the received synchronization information for synchronization calibration and does not monitor the accuracy of the synchronization information. If the time synchronization information received by the time-aware system is too offset, the synchronization error will spread to the network behind the time-aware system as it is forwarded by the time-aware system, causing inaccurate synchronization of the subsequent time-aware system. This synchronization inaccuracy may cause the performance of delay-sensitive applications to decline or even be lost, which has a serious impact on scenarios with high time requirements such as the Industrial Internet.

[0004] Therefore, it is necessary to design a method that can monitor the accuracy of received time synchronization messages in real time on a time-aware system to ensure the accuracy of time synchronization in a time-sensitive network. Summary of the invention

[0005] In view of this, the embodiments of the present application provide a time synchronization accuracy self-monitoring method, a time perception system and a self-monitoring system for a time-sensitive network to eliminate or improve one or more defects existing in the prior art.

[0006] One aspect of the present application provides a method for self-monitoring time synchronization accuracy for a time-sensitive network, the method being performed by a time-aware system in the time-sensitive network, the method comprising:

[0007] In a time-sensitive network, a synchronization message and a follow-up message uniquely corresponding to the synchronization message are sequentially received from a previous node in a time synchronization information transmission path where the previous node is located, wherein the previous node is a preset master clock node or other time perception system;

[0008] Acquire a local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node;

[0009] Based on the preset time synchronization accuracy rules, the local clock offset value is self-monitored for time synchronization accuracy. If it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rules, the local clock is calibrated based on the local clock offset value.

[0010] In some embodiments of the present application, before sequentially receiving the synchronization messages sent successively by the previous node in the time synchronization information transmission path where the node is located and the follow-up message uniquely corresponding to the synchronization message, the method further includes:

[0011] Receiving time synchronization accuracy self-monitoring parameters sent by a centralized network manager, wherein the time synchronization accuracy self-monitoring parameters include: a monitoring period, a time offset threshold, and an offset upper limit value;

[0012] The monitoring period, the time offset threshold and the offset upper limit value are stored locally, and counters corresponding to the monitoring period and the offset upper limit value are constructed respectively, wherein the counter corresponding to the monitoring period is cyclically accumulated and cleared based on the value of the monitoring period, and each time the counter corresponding to the monitoring period is cleared, the counter corresponding to the offset upper limit value is also cleared;

[0013] Correspondingly, based on the preset time synchronization accuracy rule, the local clock offset value is self-monitored for time synchronization accuracy, and if it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rule, the local clock is calibrated based on the local clock offset value, including:

[0014] It is determined whether the local clock offset value is greater than the time offset threshold, and if not, it is determined that the local clock offset value satisfies the time synchronization accuracy rule, so as to calibrate the local clock based on the local clock offset value.

[0015] In some embodiments of the present application, the time synchronization accuracy self-monitoring method for a time-sensitive network further includes:

[0016] If the local clock offset value does not meet the time synchronization accuracy rule, the value of the counter corresponding to the offset upper limit value is increased by 1, and it is determined whether the value of the counter corresponding to the current offset upper limit value exceeds the offset upper limit value. If not, the local clock offset value is marked as not to calibrate the local clock.

[0017] In some embodiments of the present application, the time synchronization accuracy self-monitoring method for a time-sensitive network further includes:

[0018] If it is determined that the value of the counter corresponding to the current offset upper limit value exceeds the offset upper limit value, the local clock offset value is marked as not to calibrate the local clock, and abnormal alarm information for the local clock offset value is generated;

[0019] The abnormal alarm information is sent to the centralized network manager so that the centralized network manager sends a corresponding maintenance trigger message to the application corresponding to the abnormal alarm information, wherein the maintenance trigger message includes: a message for triggering the re-verification, calibration or re-synchronization process of the application, a message for triggering the application to request a new transmission path, and a message for triggering the application to suspend or terminate the time synchronization operation or process.

[0020] In some embodiments of the present application, before sequentially receiving the synchronization messages sent successively by the previous node in the time synchronization information transmission path where the node is located and the follow-up message uniquely corresponding to the synchronization message in the time-sensitive network, the method further includes:

[0021] Based on a preset propagation delay measurement algorithm, the propagation delay between the master clock port of the node itself and the slave clock port of the adjacent previous node is calculated as the propagation delay between the node itself and the previous node.

[0022] In some embodiments of the present application, in a time-sensitive network, sequentially receiving synchronization messages sent successively by a previous node in a time synchronization information transmission path where the node is located and a follow-up message uniquely corresponding to the synchronization message includes:

[0023] In a time-sensitive network, receiving a synchronization message sent by a previous node in a time synchronization information transmission path in which the network is located, and generating a corresponding reception message timestamp when receiving the synchronization message; wherein the time synchronization information transmission path is generated in advance by a centralized network manager after selecting a master clock node in the time-sensitive network;

[0024] In a time-sensitive network, a follow-up message sent by the previous node and uniquely corresponding to the synchronization message is received, and a corresponding message sending timestamp and a correction field are extracted from the follow-up message.

[0025] In some embodiments of the present application, the acquiring of the local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node includes:

[0026] A local clock offset value is calculated according to the received message timestamp, the message sent timestamp, the correction domain, and a preset propagation delay between itself and the previous node.

[0027] Another aspect of the present application provides a time perception system in a time sensitive network, including:

[0028] A message receiving module is used to sequentially receive, in a time-sensitive network, synchronization messages sent successively by a previous node in a time synchronization information transmission path in which the previous node is located and a follow-up message uniquely corresponding to the synchronization message, wherein the previous node is a preset master clock node or other time perception system;

[0029] An offset value generating module, configured to obtain a local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node;

[0030] The accuracy self-monitoring module is used to perform time synchronization accuracy self-monitoring on the local clock offset value based on preset time synchronization accuracy rules. If it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rules, the local clock is calibrated based on the local clock offset value.

[0031] A third aspect of the present application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the method for self-monitoring time synchronization accuracy for a time-sensitive network when executing the computer program.

[0032] A fourth aspect of the present application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for self-monitoring time synchronization accuracy for a time-sensitive network.

[0033] A fifth aspect of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the method for self-monitoring time synchronization accuracy for a time-sensitive network.

[0034] A sixth aspect of the present application provides a time synchronization accuracy self-monitoring system for a time-sensitive network, comprising: a centralized network manager and respective time perception systems respectively connected to the centralized network manager for communication, and the respective time perception systems are sequentially connected in a time synchronization information transmission path headed by a master clock node;

[0035] The time perception system is used to execute the time synchronization accuracy self-monitoring method for a time-sensitive network.

[0036] The present application provides a method for self-monitoring time synchronization accuracy for a time-sensitive network, which is executed by a time perception system in the time-sensitive network. The method receives, in the time-sensitive network, synchronization messages and follow-up messages uniquely corresponding to the synchronization messages, which are successively sent by a previous node in a time synchronization information transmission path in which the method is located, wherein the previous node is a preset master clock node or other time perception system; obtains a local clock offset value based on the synchronization message, the follow-up message and a preset propagation delay between the method and the previous node; performs self-monitoring of time synchronization accuracy on the local clock offset value based on preset time synchronization accuracy rules; if it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rules, calibrates the local clock based on the local clock offset value, and can monitor the accuracy of the received time synchronization message in real time on the time perception system, can ensure the accuracy of time synchronization in the time-sensitive network, and further can ensure the performance of delay-sensitive applications, which is particularly suitable for scenarios with high time requirements such as the industrial Internet.

[0037] Additional advantages, purposes, and features of the present application will be partially described in the following description, and will become partially apparent to those skilled in the art after studying the following, or may be learned from the practice of the present application. The purposes and other advantages of the present application can be achieved and obtained by the structures specifically pointed out in the specification and the drawings.

[0038] Those skilled in the art will understand that the purposes and advantages that can be achieved by the present application are not limited to the above specific description, and the above and other purposes that can be achieved by the present application will be more clearly understood based on the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The drawings described herein are used to provide a further understanding of the present application, constitute a part of the present application, and do not constitute a limitation of the present application. The components in the drawings are not drawn to scale, but are only for the purpose of illustrating the principles of the present application. In order to facilitate the illustration and description of some parts of the present application, the corresponding parts in the drawings may be enlarged, that is, they may become larger relative to other components in the exemplary device actually manufactured according to the present application. In the drawings:

[0040] Figure 1 1 is a schematic diagram of a first flow chart of a method for self-monitoring time synchronization accuracy in a time-sensitive network in an embodiment of the present application.

[0041] Figure 2 A schematic diagram of a time synchronization information transmission path in one embodiment of the present application.

[0042] Figure 3 1 is a schematic diagram of a second flow chart of a method for self-monitoring time synchronization accuracy in a time-sensitive network in an embodiment of the present application.

[0043] Figure 4 This is a schematic diagram of the clock calibration process of a time perception system in an application example of the present application.

[0044] Figure 5 Schematic diagram of the structure of a time perception system in a time sensitive network in one embodiment of the present application.

[0045] Figure 6 Schematic diagram of the architecture of a time synchronization accuracy self-monitoring system for a time-sensitive network in an embodiment of the present application. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the implementation modes and the accompanying drawings. Here, the illustrative implementation modes and descriptions of the present application are used to explain the present application, but are not intended to limit the present application.

[0047] It should also be noted here that in order to avoid obscuring the present application due to unnecessary details, only the structures and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0048] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, elements, steps or components, but does not exclude the presence or addition of one or more other features, elements, steps or components.

[0049] It should also be noted that, unless otherwise specified, the term “connection” herein may refer not only to a direct connection but also to an indirect connection with an intermediate.

[0050] Hereinafter, embodiments of the present application will be described with reference to the accompanying drawings. In the accompanying drawings, the same reference numerals represent the same or similar components, or the same or similar steps.

[0051] With the development of real-time systems such as automobiles, aerospace, industrial automation, and industrial control, the growing data flow business has put forward high bandwidth and low latency requirements for communication networks. However, traditional industrial fieldbus technology and traditional Ethernet technology cannot meet the real-time requirements of the above communication systems. Therefore, different companies have proposed different real-time Ethernet solutions, such as EtherCAT, ProfiNet, and POWERLINK. Although these protocols meet the real-time and deterministic requirements of communication in various fields, Industry 4.0 requires IT (Information Technology) and OT (Operation Technology) to interact. Due to the competition among different manufacturers, the above protocols are difficult to standardize and are incompatible with each other. Different devices cannot achieve interoperability and cannot solve the integration problem of IT and OT.

[0052] In 2005, the IEEE 802.1 working group established the AVB (Audio Video Bridging) working group to ensure the real-time transmission of audio and video streams, which is suitable for industrial fields such as automobiles and avionics that require high bandwidth and low latency. However, AVB lacks fault-tolerant mechanisms to enhance reliability and security protection measures against malicious attacks. Therefore, in 2012, the IEEE 802.1 working group expanded AVB and renamed it the TSN (Time Sensitive Networking) working group, enhancing and supplementing the real-time capabilities in AVB.

[0053] The IEEE 802.1AS protocol is an important part of the IEEE 802.1 protocol. Many TSN protocols are based on network-wide precise time synchronization, that is, all TSN network entities share an established common time reference. The IEEE 802.1AS protocol uses the IEEE 1588 dedicated profile gPTP (general Precise Time Protocol). gPTP synchronizes the clocks of network devices by transmitting relevant time event messages. Time messages are transmitted between the master port and the slave port to form a time-aware network, also known as a gPTP domain. The best master clock algorithm BMCA (Best Master Clock Algorithm) is used in the gPTP domain to select the most accurate clock source in the current domain, and all other time-aware systems are synchronized with the best master clock. During initialization, the best master clock is first selected to establish the corresponding time synchronization spanning tree, and then the synchronization operation is performed, including calculating the link delay between the master and slave clocks, and the best master clock publishing time synchronization information.

[0054] In order to monitor the accuracy of time synchronization messages received on a time-aware system in real time during the time synchronization process, the embodiments of the present application respectively provide a method for self-monitoring time synchronization accuracy for a time-sensitive network, a time-aware system in a time-sensitive network for executing the method for self-monitoring time synchronization accuracy for a time-sensitive network, a self-monitoring system for time synchronization accuracy for a time-sensitive network, a physical device, a computer-readable storage medium and a computer program product, which can monitor the accuracy of received time synchronization messages in real time on the time-aware system and ensure the accuracy of time synchronization in the time-sensitive network.

[0055] The details are described in detail through the following examples.

[0056] Based on this, the embodiment of the present application provides a method for self-monitoring the time synchronization accuracy of a time-sensitive network that can be implemented by a time perception system in the time-sensitive network, see Figure 1 The time synchronization accuracy self-monitoring method for a time-sensitive network specifically includes the following contents:

[0057] Step 100: In a time-sensitive network, sequentially receive synchronization messages and follow-up messages uniquely corresponding to the synchronization messages sent by a previous node in a time synchronization information transmission path where the previous node is located, wherein the previous node is a preset master clock node or other time perception system.

[0058] In one or more embodiments of the present application, a synchronization message may refer to a Sync message, and a follow message may refer to a Follow_Up message corresponding to the Sync message. The expression of the follow message in the present application is only to distinguish it from the Follow_Up message. In fact, the Follow_Up message is also a synchronization message, such as Figure 2 The Sync message and the Follow_Up message together constitute a group of time synchronization messages, which are sent by the master clock node in the time-sensitive network as the source.

[0059] It is understandable that the master clock node may be referred to as the best master clock, which may be pre-selected by the centralized network manager CNC. Specifically, initially, the centralized network manager CNC selects the best master clock in the time synchronization domain and generates a time synchronization spanning tree, which is used to display the time synchronization information transmission path with the master clock node as the source, see Figure 2 , the master and slave clocks of each time perception system in the time synchronization information transmission path are connected in sequence. For the time perception system that executes the time synchronization accuracy self-monitoring method for time-sensitive networks of the present application, if it is the first time perception system other than the master clock node in the time synchronization information transmission path, then its previous node in the time synchronization information transmission path is the master clock node; if the time perception system that executes the time synchronization accuracy self-monitoring method for time-sensitive networks of the present application is not the first time perception system other than the master clock node in the time synchronization information transmission path, then its previous node in the time synchronization information transmission path is another time perception system.

[0060] Step 200: Acquire a local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node.

[0061] In step 200, the propagation delay D between itself and the previous node s,r It can be pre-calculated by a time-aware system that executes the time synchronization accuracy self-monitoring method for time-sensitive networks of the present application, where s is used to represent the previous node, and r represents the node currently calculating the propagation delay, which can be any time-aware system. Figure 2 , the propagation delay from time-aware system i-1 to time-aware system i is D i-1,i , the propagation delay from time-aware system i to time-aware system i+1 is D i,i+1 .

[0062] Step 300: Based on the preset time synchronization accuracy rules, the local clock offset value is self-monitored for time synchronization accuracy. If it is determined through monitoring that the local clock offset value meets the time synchronization accuracy rules, the local clock is calibrated based on the local clock offset value.

[0063] In one or more embodiments of the present application, the time synchronization accuracy rules can be set in advance by humans, or can be adjusted according to actual application needs, which may include one or more time synchronization accuracy conditions. For example, one of the time synchronization accuracy conditions can be to determine whether the local clock offset value exceeds the time offset threshold. If not, it means that the time synchronization accuracy condition is met.

[0064] From the above description, it can be seen that the self-monitoring method for time synchronization accuracy for time-sensitive networks provided in the embodiments of the present application can monitor the accuracy of received time synchronization messages in real time on the time-aware system, can ensure the accuracy of time synchronization in the time-sensitive network, and thus can ensure the performance of delay-sensitive applications, and is particularly suitable for scenarios with high time requirements such as the industrial Internet.

[0065] In order to further improve the effectiveness and reliability of self-monitoring of time synchronization accuracy for time-sensitive networks, in a method for self-monitoring time synchronization accuracy for time-sensitive networks provided in an embodiment of the present application, see Figure 3 The method for self-monitoring the time synchronization accuracy of a time-sensitive network further specifically includes the following contents before step 100:

[0066] Step 010: receiving time synchronization accuracy self-monitoring parameters sent by a centralized network manager, wherein the time synchronization accuracy self-monitoring parameters include: a monitoring period, a time offset threshold, and an offset upper limit value;

[0067] Step 020: Locally store the monitoring period, time offset threshold and offset upper limit value, and construct counters corresponding to the monitoring period and the offset upper limit value respectively, wherein the counter corresponding to the monitoring period is cyclically accumulated and cleared based on the value of the monitoring period, and each time the counter corresponding to the monitoring period is cleared, the counter corresponding to the offset upper limit value is also cleared.

[0068] In one or more embodiments of the present application, the monitoring cycle monitorCycle, the time offset threshold offset th and offset upper limit value offset lim The parameters constitute the time synchronization accuracy self-monitoring parameters, which can be referred to as monitoring parameters. The CNC sends the monitoring parameters to the time perception system. The time perception system configures the local monitoring parameters according to the sent monitoring parameters and initializes the corresponding counter initial value.

[0069] After the system is powered on, the time-aware system runs the BMCA algorithm in IEEE 802.1AS to select the best master clock and generate a synchronization spanning tree.

[0070] The CNC sends the monitoring parameters to the time perception system. The monitoring parameters can be the default values ​​initialized by the CNC or customized parameters generated by the CNC based on the user's QoS requirements. The monitoring parameters include the time offset threshold offset. th , monitoring cycle monitorCycle and offset upper limit offset lim .

[0071] After receiving the monitoring parameters sent by the CNC, the time perception system sets three local monitoring parameters, namely the local time offset threshold offset th , monitoring cycle monitorCycle and offset upper limit offset lim The corresponding counter of the parameter initialization, the counter of the monitoring cycle monitorCycle is accumulated and cleared according to the value of monitorCycle. Each time it is cleared, the offset upper limit offset is lim The counter value is cleared.

[0072] For the corresponding Figure 3 Step 300 of the method for self-monitoring time synchronization accuracy in a time-sensitive network specifically includes the following contents:

[0073] Step 310: Determine whether the local clock offset value is greater than the time offset threshold, if not, execute step 320;

[0074] Step 320: Determine whether the local clock offset value satisfies the time synchronization accuracy rule, so as to calibrate the local clock based on the local clock offset value.

[0075] That is, the local time perception system calculates the local clock offset value offset and adds the offset to the time offset threshold offset. th Compare, if offset is less than or equal to offset th , then use offset to calibrate the local clock.

[0076] In order to further improve the effectiveness and reliability of self-monitoring of time synchronization accuracy for time-sensitive networks, in a method for self-monitoring time synchronization accuracy for time-sensitive networks provided in an embodiment of the present application, see Figure 3 The time synchronization accuracy self-monitoring method for a time-sensitive network further specifically includes the following contents after step 310:

[0077] If it is determined in step 310 that the local clock offset value is greater than the time offset threshold, then step 330 is executed;

[0078] Step 330: If the local clock offset value does not satisfy the time synchronization accuracy rule, then the value of the counter corresponding to the offset upper limit value is increased by 1;

[0079] Step 340: determine whether the value of the counter corresponding to the current offset upper limit value exceeds the offset upper limit value, if not, execute step 350;

[0080] Step 350: Mark the local clock offset value as not to calibrate the local clock.

[0081] That is, if the comparison result offset is greater than offset th , then no local clock calibration is performed, and the upper limit offset is set lim The counter value is incremented by one; then the current offset is compared lim Counter value and offset lim The size of offset lim The counter value is less than or equal to offset lim , the local clock will not be calibrated and will not be reported.

[0082] In order to further improve the comprehensiveness and reliability of the application of time synchronization accuracy self-monitoring for time-sensitive networks, in a method for self-monitoring time synchronization accuracy for time-sensitive networks provided in an embodiment of the present application, see Figure 3 The time synchronization accuracy self-monitoring method for a time-sensitive network further specifically includes the following contents after step 340:

[0083] If it is determined in step 340 that the value of the counter corresponding to the current offset upper limit value is greater than the offset upper limit value, then step 360 is executed;

[0084] Step 360: If it is determined that the value of the counter corresponding to the current offset upper limit value exceeds the offset upper limit value, the local clock offset value is marked as not to calibrate the local clock, and abnormal alarm information for the local clock offset value is generated.

[0085] Step 370: Send the abnormal alarm information to the centralized network manager, so that the centralized network manager sends a corresponding maintenance trigger message to the application corresponding to the abnormal alarm information, wherein the maintenance trigger message includes: a message for triggering the re-verification, calibration or re-synchronization process of the application, a message for triggering the application to request a new transmission path, and a message for triggering the application to suspend or terminate the time synchronization operation or process.

[0086] That is to say, if the upper limit offset lim The counter value is greater than the offset upper limit offset lim , the local clock calibration is not performed, and the current time perception system reports to the CNC for alarm.

[0087] After receiving the alarm from the local time perception system, CNC can notify the application to take corresponding countermeasures, including but not limited to triggering the application's re-verification, calibration, and re-synchronization process, triggering the application to request a new transmission path, and triggering the application to suspend or terminate operations or processes that require time synchronization. Therefore, the accuracy of the received time synchronization message can be monitored in real time to ensure the quality of time synchronization in the TSN network.

[0088] In order to further improve the accuracy of the results of the self-monitoring of the time synchronization accuracy of the time-sensitive network, in a method for self-monitoring the time synchronization accuracy of the time-sensitive network provided in an embodiment of the present application, see Figure 3 The method for self-monitoring the time synchronization accuracy of a time-sensitive network further specifically includes the following contents before step 100:

[0089] Step 030: Based on a preset propagation delay measurement algorithm, the propagation delay between the master clock port of the node itself and the slave clock port of the adjacent previous node is calculated as the propagation delay between the node itself and the previous node.

[0090] Specifically, the time-aware system i in the network runs the propagation delay measurement algorithm in the IEEE 80222.1AS protocol, see Figure 2 , the measured propagation delay from time-aware system i-1 to time-aware system i is D i-1,i .

[0091] In order to further improve the application reliability of time synchronization accuracy self-monitoring for time-sensitive networks, in a time synchronization accuracy self-monitoring method for a time-sensitive network provided in an embodiment of the present application, see Figure 3 Step 100 of the method for self-monitoring time synchronization accuracy in a time-sensitive network specifically includes the following contents:

[0092] Step 110: In a time-sensitive network, receive a synchronization message sent by a previous node in the time synchronization information transmission path in which the network is located, and generate a corresponding reception message timestamp when the synchronization message is received; wherein, the time synchronization information transmission path is generated in advance by a centralized network manager after selecting a master clock node in the time-sensitive network.

[0093] Step 120: In a time-sensitive network, a follow-up message sent by the previous node and uniquely corresponding to the synchronization message is received, and a corresponding message sending timestamp and correction field are extracted from the follow-up message.

[0094] The message sending timestamp is represented by preciseOriginTimestamp, and the correction field is represented by correctionField. s , where s represents any one of the 1st, ..i-1th, i and i+1th time perception systems, and 1 is a positive integer greater than 1.

[0095] For example, the best master clock runs the time synchronization information transmission algorithm and periodically sends Sync and Follow_Up time synchronization messages. The preciseOriginTimestamp in the Follow_Up message indicates the time when the Sync message is sent. Figure 2 After receiving the Sync message, the time-aware system i-1 generates the corresponding receiving message timestamp t r,i and record it, then s,i-1 Forward the Sync message to the time-aware system i at all times, and after a period of time, send the Follow_Up message to the time-aware system i, which carries the preciseOriginTimestamp and correctionField of this synchronization. i-1 , clock frequency ratio and other information.

[0096] In order to further improve the application reliability of time synchronization accuracy self-monitoring for time-sensitive networks, in a time synchronization accuracy self-monitoring method for a time-sensitive network provided in an embodiment of the present application, see Figure 3 Step 200 of the method for self-monitoring time synchronization accuracy in a time-sensitive network specifically includes the following contents:

[0097] Step 210: Calculate a local clock offset value according to the received message timestamp, the message sent timestamp, the correction domain, and a preset propagation delay between itself and the previous node.

[0098] Specifically, the time-aware system receives the Follow_Up message after a period of time and calculates the local clock offset value offset; wherein the local clock offset value offset is determined according to the following formula:

[0099] offset=preciseOriginTimeStamp+correctionField i-1 +D i-1,i -t r,i

[0100] The formula does not take into account the effect of the clock frequency ratio when calculating. If necessary, it can be converted to the same clock reference.

[0101] By using the above method and steps, before the time-aware system receives the synchronization information message for clock calibration, it can check the accuracy of the time synchronization message to ensure that the network will not be affected by inaccurate time synchronization messages. Therefore, the time-aware network can perform accurate time synchronization, ensure the normal operation of time-sensitive applications, and promptly know if there is an abnormality in the synchronization accuracy of the time-aware system and make corresponding responses.

[0102] In order to further illustrate the above scheme, the present application also provides a specific application example of a method for self-monitoring the time synchronization accuracy of a time-sensitive network, which belongs to the field of network communication technology, vehicle-mounted network and new industrial Internet related to time synchronization, and specifically involves a TSN (Time Sensitive Networking) scenario, in which time synchronization self-monitoring improves the accuracy of TSN network time synchronization. The purpose is to provide a method for self-monitoring the accuracy of TSN time synchronization, which can monitor the accuracy of the time synchronization message received on the time perception system in real time during the time synchronization process. When the time offset calculated by the time perception system based on the received time synchronization message exceeds the set value, it can promptly report to the CNC (Centralized Network Configuration) to alarm, and the CNC notifies the corresponding application to process. By using this solution, the time synchronization accuracy of each device in the TSN network can be monitored in real time to ensure the accuracy of time synchronization in the TSN network.

[0103] See also Figure 4 , the application example specifically includes the following contents:

[0104] (1) Step 1: After the CNC selects the best master clock in the time-aware network and builds a time synchronization spanning tree, it sends the parameters required for self-monitoring to each time-aware system. The parameters sent include the time offset threshold, monitoring period, and offset upper limit. The CNC configures the execution action when the alarm is triggered.

[0105] The parameters required for self-monitoring sent by the CNC are statically configured default values; the parameters required for self-monitoring sent by the CNC may be customized parameters generated by the CNC according to user QoS requirements.

[0106] The actions performed by the time perception system described in step 1 after receiving the parameters sent by the CNC are specifically:

[0107] The time perception system sets the local time offset threshold offset according to the parameters issued th , monitoring cycle monitorCycle and offset upper limit offset lim Static parameters, the three static parameters are set to count the corresponding counting variables. Among them, the monitoring cycle counter is cycled and accumulated according to the value of monitorCycle. Each time it is cleared, the offset lim The counter value is cleared.

[0108] The execution actions configured in the CNC when the alarm is triggered as described in step 1 are specifically:

[0109] After receiving the alarm information reported by the time perception system, the CNC may perform actions including but not limited to triggering the application's re-verification, calibration, and re-synchronization process, triggering the application to request a new transmission path, and triggering the application to suspend or terminate operations or processes that require time synchronization.

[0110] (2) Step 2: All time-aware systems in the time-aware network run a propagation delay measurement algorithm to calculate the propagation delay between all master and slave clock ports;

[0111] (3) Step 3: The best master clock runs the time synchronization information transmission algorithm and sends the time synchronization message to all time-aware systems in sequence along the time synchronization information transmission path. After receiving the time synchronization message, the time-aware system calibrates the local clock value and generates a new time synchronization message to forward to the downstream time-aware system.

[0112] The step 3 of receiving the time synchronization message and performing the clock calibration operation is specifically as follows:

[0113] Step 3.1: After receiving the Sync time synchronization message from the clock port, sample and generate the timestamp t r ;

[0114] Step 3.2, after receiving the Follow_Up time synchronization message from the clock port, obtain the preciseOriginTimestamp and correctionField s And other parameters;

[0115] Step 3.3, using the parameters in step 3.1, step 3.2 and step 2, calculate the local clock offset of the time-aware system.

[0116] Step 3.4, compare offset with time offset threshold offset th If the value of offset is less than or equal to offset th , the local clock uses the offset value for clock calibration.

[0117] Step 3.5, if the value of offset is greater than offset th , offset lim The counter value is incremented by one, and the value is checked to see if it exceeds the offset. lim If it does not exceed the value, the local clock calibration will not be performed and the CNC will not be reported.

[0118] Step 3.5, if offset lim The counter value exceeds the offset lim , a message is directly sent to the CNC for alarm, and the local clock is not calibrated.

[0119] The local clock offset is calculated according to the following formula:

[0120] offset=preciseOriginTimeStamp+correctionField s +D s,r -t r ;

[0121] Where D s,r It is the propagation delay from the upstream master clock of the current time perception system to the current time perception system. Note that the influence of the clock frequency ratio is not considered in the calculation here. If necessary, it can be converted to a unified clock reference.

[0122] (4) Step 4: During the time synchronization information transmission process, if the time perception system detects that the number of times the clock offset exceeds the time offset threshold within the monitoring period exceeds the set offset upper limit, the time perception system will report to the CNC to alarm.

[0123] That is to say, the application example of this application proposes a self-monitoring method for TSN time synchronization accuracy. Initially, the best master clock algorithm BMCA is run in the time perception domain to select the best master clock and generate a synchronization spanning tree, and the CNC sends the parameters required for self-monitoring to all time perception systems. Furthermore, the time perception system measures the propagation delay between each master and slave clock port according to the propagation delay measurement algorithm. Furthermore, the best master clock sends a time synchronization message to perform time synchronization in the time perception domain. When the time perception system receives the time synchronization message, it is proposed for the first time by this application that after calculating the local clock offset, the offset value is checked for accuracy, and the local clock calibration is determined based on the check result, and whether to trigger the action of reporting to the CNC for alarm. It can better guarantee the accuracy of clock synchronization; it can achieve accurate deterministic scheduling on the basis of ensuring the high accuracy of clock synchronization; the application example of this application can be effectively used in scenarios such as vehicle-mounted TSN networks and industrial Internet.

[0124] The present application also provides a time-aware system in a time-sensitive network for executing all or part of the time synchronization accuracy self-monitoring method for a time-sensitive network, see Figure 5 The time perception system in the time sensitive network specifically includes the following contents:

[0125] The message receiving module 10 is used to sequentially receive the synchronization messages sent by the previous node in the time synchronization information transmission path in the time-sensitive network and the follow-up message uniquely corresponding to the synchronization message, wherein the previous node is a preset master clock node or other time perception system;

[0126] An offset value generating module 20, configured to obtain a local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node;

[0127] The accuracy self-monitoring module 30 is used to perform time synchronization accuracy self-monitoring on the local clock offset value based on preset time synchronization accuracy rules. If it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rules, the local clock is calibrated based on the local clock offset value.

[0128] The embodiment of the time perception system in the time-sensitive network provided in the present application can be specifically used to execute the processing flow of the embodiment of the method for self-monitoring time synchronization accuracy for the time-sensitive network in the above-mentioned embodiment. Its functions are not repeated here, and reference can be made to the detailed description of the embodiment of the method for self-monitoring time synchronization accuracy for the time-sensitive network.

[0129] The time perception system in the time sensitive network performs self-monitoring of the time synchronization accuracy of the time sensitive network in the client device. The selection can be made based on the processing capability of the client device and the limitations of the user's usage scenario. This application does not limit this. If all operations are completed in the client device, the client device may also include a processor for specific processing of self-monitoring of the time synchronization accuracy of the time sensitive network.

[0130] The client device may have a communication module (i.e., a communication unit) that can communicate with a remote server to achieve data transmission with the server. The server may include a server on the task scheduling center side, and other implementation scenarios may also include a server on an intermediate platform, such as a server on a third-party server platform that has a communication link with the task scheduling center server. The server may include a single computer device, or a server cluster consisting of multiple servers, or a server structure of a distributed device.

[0131] The server and the client device may communicate with each other using any suitable network protocol, including network protocols that have not yet been developed on the date of filing this application. The network protocols may include, for example, TCP / IP, UDP / IP, HTTP, HTTPS, etc. Of course, the network protocols may also include, for example, RPC (Remote Procedure Call Protocol) and REST (Representational State Transfer) protocols used on top of the above protocols.

[0132] From the above description, it can be seen that the time perception system in the time-sensitive network provided in the embodiment of the present application can monitor the accuracy of the received time synchronization messages in real time on the time perception system, can ensure the accuracy of time synchronization in the time-sensitive network, and further can ensure the performance of delay-sensitive applications, which is particularly suitable for scenarios with high time requirements such as the industrial Internet.

[0133] The present application also provides a time synchronization accuracy self-monitoring system for a time-sensitive network, and the time synchronization accuracy self-monitoring system specifically includes the following contents:

[0134] A centralized network manager CNC and various time perception systems respectively connected to the centralized network manager for communication, and each time perception system is connected in sequence in a time synchronization information transmission path headed by a master clock node; the time perception system is used in the time synchronization accuracy self-monitoring method for a time-sensitive network in the aforementioned embodiment.

[0135] In one example, see Figure 6 The architecture of the time synchronization accuracy self-monitoring system for time-sensitive networks can be composed of TSN switches, TSN terminals, centralized user configuration CUC and centralized network configuration CNC, wherein the TSN switch is used to send or forward time synchronization information; the TSN terminal is used to send or receive time synchronization information; CNC refers to a centralized network configuration instance, which is used to configure and manage TSN switches; CUC refers to a centralized user configuration instance, which is used to obtain TSN end system requirements and transmit process data to CNC.

[0136] The embodiment of the present application also provides an electronic device, which may include a processor, a memory, a receiver and a transmitter, wherein the processor is used to execute the time synchronization accuracy self-monitoring method for a time-sensitive network mentioned in the above embodiment, wherein the processor and the memory may be connected via a bus or other means, such as by bus connection. The receiver may be connected to the processor and the memory via wired or wireless means.

[0137] The processor may be a central processing unit (CPU). The processor may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0138] As a non-transient computer-readable storage medium, the memory can be used to store non-transient software programs, non-transient computer executable programs and modules, such as the program instructions / modules corresponding to the time synchronization accuracy self-monitoring method for time-sensitive networks in the embodiments of the present application. The processor executes various functional applications and data processing of the processor by running the non-transient software programs, instructions and modules stored in the memory, that is, the time synchronization accuracy self-monitoring method for time-sensitive networks in the above method embodiments is implemented.

[0139] The memory may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created by the processor, etc. In addition, the memory may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory may optionally include a memory remotely arranged relative to the processor, and these remote memories may be connected to the processor via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0140] The one or more modules are stored in the memory, and when executed by the processor, perform the time synchronization accuracy self-monitoring method for a time-sensitive network in the embodiment.

[0141] In some embodiments of the present application, the user equipment may include a processor, a memory, and a transceiver unit, which may include a receiver and a transmitter. The processor, memory, receiver, and transmitter may be connected through a bus system. The memory is used to store computer instructions, and the processor is used to execute the computer instructions stored in the memory to control the transceiver unit to send and receive signals.

[0142] As an implementation method, the functions of the receiver and the transmitter in the present application can be considered to be implemented through a transceiver circuit or a dedicated chip for transceiver, and the processor can be considered to be implemented through a dedicated processing chip, a processing circuit or a general chip.

[0143] As another implementation method, it is possible to use a general-purpose computer to implement the server provided in the embodiment of the present application, that is, to store the program code for implementing the functions of the processor, receiver, and transmitter in a memory, and the general-purpose processor implements the functions of the processor, receiver, and transmitter by executing the code in the memory.

[0144] The embodiment of the present application also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the aforementioned method for self-monitoring the time synchronization accuracy of a time-sensitive network are implemented. The computer-readable storage medium can be a tangible storage medium, such as a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a floppy disk, a hard disk, a removable storage disk, a CD-ROM, or any other form of storage medium known in the technical field.

[0145] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the aforementioned method for self-monitoring time synchronization accuracy for a time-sensitive network.

[0146] It should be understood by those skilled in the art that the exemplary components, systems and methods described in conjunction with the embodiments disclosed herein can be implemented in hardware, software or a combination of the two. Whether it is specifically performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application. When implemented in hardware, it can be, for example, an electronic circuit, an application specific integrated circuit (ASIC), appropriate firmware, a plug-in, a function card, etc. When implemented in software, the elements of this application are programs or code segments used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link via a data signal carried in a carrier.

[0147] It should be clear that the present application is not limited to the specific configuration and processing described above and shown in the figures. For the sake of simplicity, a detailed description of the known method is omitted here. In the above embodiments, several specific steps are described and shown as examples. However, the method process of the present application is not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications and additions, or change the order between the steps after understanding the spirit of the present application.

[0148] In the present application, features described and / or illustrated for one embodiment may be used in the same manner or in a similar manner in one or more other embodiments, and / or combined with features of other embodiments or replace features of other embodiments.

[0149] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the embodiments of the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for self-monitoring time synchronization accuracy in a time-sensitive network, characterized in that: The method is performed by a time-aware system in a time-sensitive network, and the method includes: In a time-sensitive network, a synchronization message and a follow-up message uniquely corresponding to the synchronization message are sequentially received from a previous node in a time synchronization information transmission path where the previous node is located, wherein the previous node is a preset master clock node or other time perception system; Acquire a local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node; Based on the preset time synchronization accuracy rules, the local clock offset value is self-monitored for time synchronization accuracy. If it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rules, the local clock is calibrated based on the local clock offset value.

2. The method for self-monitoring time synchronization accuracy for a time-sensitive network according to claim 1, characterized in that: Before sequentially receiving the synchronization messages sent by the previous node in the time synchronization information transmission path where the node is located and the follow-up message uniquely corresponding to the synchronization message, the method further includes: Receiving time synchronization accuracy self-monitoring parameters sent by a centralized network manager, wherein the time synchronization accuracy self-monitoring parameters include: a monitoring period, a time offset threshold, and an offset upper limit value; The monitoring period, the time offset threshold and the offset upper limit value are stored locally, and counters corresponding to the monitoring period and the offset upper limit value are constructed respectively, wherein the counter corresponding to the monitoring period is cyclically accumulated and cleared based on the value of the monitoring period, and each time the counter corresponding to the monitoring period is cleared, the counter corresponding to the offset upper limit value is also cleared; Correspondingly, based on the preset time synchronization accuracy rule, the local clock offset value is self-monitored for time synchronization accuracy, and if it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rule, the local clock is calibrated based on the local clock offset value, including: It is determined whether the local clock offset value is greater than the time offset threshold, and if not, it is determined that the local clock offset value satisfies the time synchronization accuracy rule, so as to calibrate the local clock based on the local clock offset value.

3. The method for self-monitoring time synchronization accuracy for a time-sensitive network according to claim 2, characterized in that: Also includes: If the local clock offset value does not meet the time synchronization accuracy rule, the value of the counter corresponding to the offset upper limit value is increased by 1, and it is determined whether the value of the counter corresponding to the current offset upper limit value exceeds the offset upper limit value. If not, the local clock offset value is marked as not to calibrate the local clock.

4. The method for self-monitoring time synchronization accuracy for a time-sensitive network according to claim 3, characterized in that: Also includes: If it is determined that the value of the counter corresponding to the current offset upper limit value exceeds the offset upper limit value, the local clock offset value is marked as not to calibrate the local clock, and abnormal alarm information for the local clock offset value is generated; The abnormal alarm information is sent to the centralized network manager so that the centralized network manager sends a corresponding maintenance trigger message to the application corresponding to the abnormal alarm information, wherein the maintenance trigger message includes: a message for triggering the re-verification, calibration or re-synchronization process of the application, a message for triggering the application to request a new transmission path, and a message for triggering the application to suspend or terminate the time synchronization operation or process.

5. The method for self-monitoring time synchronization accuracy for a time-sensitive network according to claim 1, characterized in that: Before sequentially receiving the synchronization messages sent successively by the previous node in the time synchronization information transmission path where the synchronization message is located and the follow-up message uniquely corresponding to the synchronization message in the time sensitive network, the method further includes: Based on a preset propagation delay measurement algorithm, the propagation delay between the master clock port of the node itself and the slave clock port of the adjacent previous node is calculated as the propagation delay between the node itself and the previous node.

6. The method for self-monitoring time synchronization accuracy for a time-sensitive network according to claim 1, characterized in that: The method of sequentially receiving the synchronization messages sent by the previous node in the time synchronization information transmission path of the time sensitive network and the follow-up message uniquely corresponding to the synchronization message includes: In a time-sensitive network, receiving a synchronization message sent by a previous node in a time synchronization information transmission path in which the network is located, and generating a corresponding reception message timestamp when receiving the synchronization message; wherein the time synchronization information transmission path is generated in advance by a centralized network manager after selecting a master clock node in the time-sensitive network; In a time-sensitive network, a follow-up message sent by the previous node and uniquely corresponding to the synchronization message is received, and a corresponding message sending timestamp and a correction field are extracted from the follow-up message.

7. The method for self-monitoring time synchronization accuracy for a time-sensitive network according to claim 6, characterized in that: The acquiring the local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node includes: A local clock offset value is calculated according to the received message timestamp, the message sent timestamp, the correction domain, and a preset propagation delay between itself and the previous node.

8. A time-aware system in a time-sensitive network, characterized in that: include: A message receiving module is used to sequentially receive, in a time-sensitive network, synchronization messages sent successively by a previous node in a time synchronization information transmission path in which the previous node is located and a follow-up message uniquely corresponding to the synchronization message, wherein the previous node is a preset master clock node or other time perception system; An offset value generating module, configured to obtain a local clock offset value based on the synchronization message, the follow-up message, and a preset propagation delay between itself and the previous node; The accuracy self-monitoring module is used to perform time synchronization accuracy self-monitoring on the local clock offset value based on preset time synchronization accuracy rules. If it is learned through monitoring that the local clock offset value meets the time synchronization accuracy rules, the local clock is calibrated based on the local clock offset value.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the method for self-monitoring time synchronization accuracy for a time-sensitive network according to any one of claims 1 to 7 is implemented.

10. A time synchronization accuracy self-monitoring system for a time-sensitive network, characterized in that: include: A centralized network manager and each time-aware system that is respectively connected to the centralized network manager in communication, and each time-aware system is sequentially connected in a time synchronization information transmission path headed by a master clock node; The time perception system is used to execute the time synchronization accuracy self-monitoring method for a time-sensitive network as described in any one of claims 1 to 7.

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