Hybrid networking synchronization path decision method and device

Abstract

The invention discloses a hybrid networking synchronization path decision method and device, and relates to the technical field of time synchronization, and the hybrid networking synchronization path decision method comprises the steps: calibrating the time precision information of a time source and a synchronization node; transmitting the time precision information of the time source and the time accumulation error information of the synchronization node to a downstream node; the downstream node decides an optimal synchronization path and the working state of a node port according to the time precision information of the time source, the time accumulation error information of the synchronization node and the local time precision information of the node, and the working state of the node port comprises a master clock state, a slave clock state and a passive clock state. The method can adapt to time sources and synchronization nodes with different time precisions, and can decide and select the optimal path with the minimum time error in a hybrid networking scene.

Description

Technical Field

[0001] The present application relates to the technical field of time synchronization, and in particular to a method and device for hybrid networking synchronization path decision. Background Art

[0002] High-precision time synchronization is one of the key requirements for 5G bearer. Different synchronization accuracies need to be provided according to different technical implementations or business scenarios. 5G synchronization requirements are mainly reflected in three aspects: basic business time synchronization requirements, collaborative business time synchronization requirements, new business time synchronization requirements, and synchronization applications in vertical industries.

[0003] The time synchronization accuracy requirement for 5G basic services is 3us, the time synchronization accuracy requirement for collaborative services is 300ns, and the time synchronization requirement for new services such as positioning is increased to 10ns. In response to different synchronization requirements, the time accuracy requirements of the corresponding time source and bearer nodes also vary. When synchronous networking, nodes with different time synchronization accuracy indicators run on the existing network at the same time, resulting in a mixed networking scenario.

[0004] The time synchronization network usually adopts the BC (Boundary Clock) model networking, and relies on the BMC (Best Master Clock) algorithm to select the time source, make synchronization path decisions, and determine the port synchronization working status. The BMC algorithm recommended in IEEE1588-2008 / 2019 or ITU-T G.8275.1 makes decisions based on the clock information carried in the synchronization announcement message (Announce) and the local clock information. For example: master clock priority 1 (GM_priority1), master clock clock class (GM_class), master clock offset Allan variance (GM_offsetScaledVariance), master clock priority 2 (GM_priority2), synchronization path hop count (StepsRemoved) and other information. By combining and comparing the information, the optimal tracking time source is determined and the synchronization tracking direction is selected. When the received master time source parameters are the same, the decisive parameter for the synchronization path decision is the synchronization path hop count (StepsRemoved). By comparison, the direction with fewer synchronization path hops is selected for tracking.

[0005] However, when devices with different time synchronization accuracies are mixed in a network, according to the traditional BMC, the time source and synchronization tracking path selected for tracking based on the time source accuracy and the number of time source hops will be non-optimal, that is, the synchronization error caused by the selected tracking time source and synchronization path is not the smallest. Summary of the invention

[0006] The present application provides a hybrid networking synchronization path decision method and device, which can adapt to time sources and synchronization nodes with different time accuracy, and in a hybrid networking scenario, can decide to select the optimal path with the smallest time error.

[0007] In a first aspect, an embodiment of the present application provides a hybrid networking synchronization path decision method, the hybrid networking synchronization path decision method comprising:

[0008] Calibrate the time accuracy information of the time source and synchronization node;

[0009] Transmit the time accuracy information of the time source and the accumulated error information of the synchronization node time to the downstream nodes;

[0010] The downstream node decides the optimal synchronization path and the working status of the node port based on the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node. The working status of the node port includes the master clock state, the slave clock state and the passive clock state.

[0011] In combination with the first aspect, in one implementation, the downstream node decides the optimal synchronization path and the working state of the node port according to the time accuracy information of the time source, the synchronization node time cumulative error information, and the local time accuracy information of the node, including:

[0012] Determine the synchronization link time error of each synchronization link corresponding to the downstream node according to the time accuracy of the time source and the sum of the synchronization node time cumulative error;

[0013] Select the synchronization link with the smallest time error as the reference synchronization link;

[0014] The difference between the synchronization link time error of each synchronization link and the reference synchronization link is calculated, and the difference is compared with the local time accuracy information of the downstream node to determine the optimal synchronization path and the working status of the node port.

[0015] In combination with the first aspect, in one implementation, the calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and deciding the working state of the optimal synchronization path and the node port includes:

[0016] If the difference is greater than the local time accuracy information of the downstream node, the reference synchronization link is determined to be the optimal synchronization path and is determined to be superior to the compared synchronization link;

[0017] In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link involved in the comparison, if the decision result is excellent, the port that decides to receive the synchronization link information works in the master clock state.

[0018] In combination with the first aspect, in one implementation, the calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and deciding the working state of the optimal synchronization path and the node port includes:

[0019] If the difference is equal to the local time accuracy information of the downstream node, further determine the size of the sending port identification number of the previous synchronization node and the receiving port identification number of the current node of the synchronization link to be compared;

[0020] If the sending port identification number is greater than the receiving port identification number, the reference synchronization link is determined to be the optimal synchronization path and is determined to be superior to the compared synchronization link;

[0021] If the sending port identification number is smaller than the receiving port identification number, the reference synchronization link is determined to be the optimal synchronization path, and the decision logic is superior to the compared synchronization link, and the reference synchronization link will be blocked by the compared synchronization link;

[0022] If the sending port identification number is equal to the receiving port identification number, a decision error is returned;

[0023] In the downstream node, the port that decides to receive the optimal synchronization path information operates in the slave clock state. For the synchronization link participating in the comparison, if the decision result is optimal, the port that decides to receive the synchronization link information operates in the master clock state. If the decision result is logically optimal, the port that decides to receive the synchronization link information operates in the passive clock state.

[0024] In combination with the first aspect, in one implementation, the calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and deciding the working state of the optimal synchronization path and the node port includes:

[0025] If the difference is greater than zero but less than the local time accuracy information of the downstream node, the reference synchronization link is determined to be the optimal synchronization path, and the decision logic is better than the compared synchronization link, and the reference synchronization link will be blocked by the compared synchronization link;

[0026] In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link participating in the comparison, if the decision result is logically excellent, the port that decides to receive the synchronization link information works in the passive clock state.

[0027] In combination with the first aspect, in one implementation, the calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and deciding the working state of the optimal synchronization path and the node port includes:

[0028] If the difference is zero, then further compare the reference synchronization link and the comparison synchronization link at the previous synchronization node.

[0029] If the sending port identification numbers are different, the synchronization link with the smaller sending port identification number is determined to be the optimal synchronization path, and the determination logic is better than the other synchronization link for comparison, the synchronization link as the optimal synchronization path will block the other synchronization link for comparison;

[0030] If the sending port identification numbers are the same, then further comparing the sizes of the receiving port numbers of the reference synchronization link and the synchronization link to be compared at the current synchronization node;

[0031] If the receiving port numbers are different, the synchronization link with the smaller receiving port number is determined to be the optimal synchronization path, and the determination logic is better than the other synchronization link for comparison, the synchronization link as the optimal synchronization path will block the other synchronization link for comparison;

[0032] If the receiving port numbers are the same, a decision error is returned;

[0033] In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link participating in the comparison, if the decision result is logically excellent, the port that decides to receive the synchronization link information works in the passive clock state.

[0034] In combination with the first aspect, in one implementation, the time accuracy information of the time source and the synchronization node time accumulated error information are transmitted through a notification message or TLV information.

[0035] In combination with the first aspect, in one implementation, relevant inherent characteristic information of the device during implementation is read to determine the time accuracy information of the synchronization node.

[0036] In a second aspect, an embodiment of the present application provides a hybrid networking synchronization path decision device, the hybrid networking synchronization path decision device comprising:

[0037] A calibration module, which is used to calibrate the time accuracy information of the time source and the synchronization node;

[0038] A transmission module, which is used to transmit the time accuracy information of the time source and the accumulated error information of the synchronization node time to the downstream node;

[0039] A decision module is used to decide the optimal synchronization path and the working state of the node port at the downstream node according to the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node. The working state of the node port includes the master clock state, the slave clock state and the passive clock state.

[0040] In combination with the second aspect, in one implementation, the decision module is used to decide the optimal synchronization path and the working state of the node port at the downstream node according to the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node, including:

[0041] Determine the synchronization link time error of each synchronization link corresponding to the downstream node according to the time accuracy of the time source and the sum of the synchronization node time cumulative error;

[0042] The synchronization link with the smallest synchronization link time error is taken as the optimal synchronization path;

[0043] The difference between the synchronization link time error of each synchronization link and the optimal synchronization path is calculated, and the difference is compared with the local time accuracy information of the downstream node to determine the working status of the node port.

[0044] The beneficial effects brought by the technical solution provided in the embodiments of the present application include:

[0045] By calibrating the time accuracy information of the time source and the synchronization node; passing the time accuracy information of the time source and the accumulated time error information of the synchronization node to the downstream node; the downstream node decides the optimal synchronization path and the working state of the node port according to the time accuracy information of the time source, the accumulated time error information of the synchronization node, and the local time accuracy information of the node, and the working state of the node port includes the master clock state, the slave clock state and the passive clock state. In this way, it can adapt to time sources and synchronization nodes with different time accuracy. In a hybrid networking scenario, it can decide to select the optimal path with the smallest time error. There is no limit on the time accuracy of the time source and synchronization node. It can be compatible with the synchronization accuracy of existing devices and can also adapt to subsequent devices with higher synchronization accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is the first example of traditional synchronization tracking in a mixed-precision time source networking scenario;

[0047] Figure 2 This is the second example of traditional synchronization tracking in a mixed-precision time source networking scenario;

[0048] Figure 3 A flow chart of an embodiment of a hybrid networking synchronization path decision method of the present application;

[0049] Figure 4 This is an example of a mixed precision time source network for this application;

[0050] Figure 5 This is a functional module diagram of an embodiment of a hybrid networking synchronization path decision device of the present application. DETAILED DESCRIPTION

[0051] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0052] When devices with different time synchronization accuracy are mixed in the network, according to the traditional BMC, the time source and synchronization tracking path selected and tracked based on the time source accuracy and the time source hop count will be non-optimal, that is, the synchronization error caused by the selected tracking time source and synchronization path is not the smallest. The technical issues are explained as follows:

[0053] Figure 1 This is an example of the tracking selection problem in the networking scenario of time sources with different precisions. Two time sources, time source 1 and time source 2, are deployed in the network. The time precision of time source 1 is 30ns, while the synchronization precision of time source 2 is 50ns. According to the traditional BMCA, node 4 will only choose to track the time source with high time precision, that is, time source 1 in the example. Then for node 4, the synchronization error caused by time source 1, node 1 and node 5 on the synchronization link is 90ns. If node 4 can track time source 2, the synchronization error is only 50ns, which is better than the decision of BMCA.

[0054] Figure 2 This is an example of the synchronization path selection problem in a mixed-precision node networking scenario. In the example, the synchronization accuracy of time source 1 is 30ns, the time accuracy of nodes 1, 2, and 3 is 5ns, and the time accuracy of nodes 4 and 5 is 30ns. For node 4, according to the traditional BMCA principle of hop-priority source selection, the direction of node 5 will be selected as the synchronization tracking direction. That is, the synchronization link is time source 1->node 1->node 5->node 4, and the statistical synchronization error of the link is 65ns. Compared with another existing synchronization link: time source 1->node 1->node 2->node 3->node 4, the statistical synchronization error of the link is 45ns. The synchronization error of the latter synchronization link is smaller than that of the previous synchronization link, but because the traditional BMCA uses the number of hops as a decision reference, the first link with a small number of hops and a large synchronization error will be selected.

[0055] To this end, the present application adopts an innovative decision-making scheme based on synchronization link accuracy to achieve the selection of the path with the minimum time error and the decision of the blocked port. In order to make the purpose, technical solution and advantages of the present application clearer, the implementation method of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0056] In a first aspect, an embodiment of the present application provides a hybrid networking synchronization path decision method.

[0057] In one embodiment, referring to Figure 3 , Figure 3 This is a flow chart of an embodiment of a hybrid networking synchronization path decision method of the present application. Figure 3 As shown, the hybrid networking synchronization path decision method includes:

[0058] S1, time accuracy information of calibration time source and synchronization node;

[0059] In existing solutions, the accuracy information of the time source is calibrated using the clockAccuracy field, which has clear encoding rules.

[0060] The synchronization node time accuracy information is missing in the existing solution and needs to be calibrated. The synchronization node time accuracy is related to the implementation scheme adopted by the device and is an inherent characteristic of the device. Therefore, after the device is developed, it can be stored in the system as device information and can be read when needed. The storage method is not limited, for example: EEPROM; it can also be configured through the management and control system; it only needs to be able to read the information accurately when making decisions. In the absence of calibration information, this solution is processed according to the agreed default value.

[0061] The time accuracy information coding can refer to the accuracy level defined in standards such as IEEE1588 and G.8273.2 for corresponding coding. For example, 0x23 indicates a synchronization accuracy of 1us, 0x21 indicates a synchronization accuracy of 100ns, and 0x1F indicates a synchronization accuracy of 10ns. It should be noted that the coded data needs to be converted into direct accuracy data when used; another solution is to calibrate directly according to the synchronization accuracy that the device can achieve. For example, if the device synchronization accuracy is 30ns, the accuracy information can be calibrated to 30ns. The advantage is that the data resolution is higher and can be used directly.

[0062] S2, transmitting the time accuracy information of the time source and the accumulated error information of the synchronization node time to the downstream node;

[0063] It is worth noting that the synchronization node time cumulative error information (sumTE_node) is the cumulative time error caused by the synchronization node in the synchronization link. This application uses the time accuracy of the synchronization node passed by the synchronization link to accumulate, indicating the maximum time error that may be caused by the synchronization node in the link.

[0064] The synchronization node time cumulative error information can be redefined in the existing message field to carry and pass it to the downstream node. For example, the Announce message field is redefined:

[0065] 1) The original "stepsRemoved" (2 bytes) field is redefined as the synchronization node time cumulative error information (sumTE_node). Considering the data bit limit and the synchronization network limit, the data precision unit can be set to 0.1ns when the link error data is stored using this solution. For example, when sumTE_node = 100ns, the stored data is 0x3E8 (0.1ns);

[0066] Alternatively, the TLV information scheme is used to carry and transmit the synchronization node time cumulative error information, which will have better compatibility and data scalability during implementation and is the preferred scheme. The specific instructions are as follows:

[0067] 1) Type: Indicates that the TLV information is the synchronization node time cumulative error information TLV;

[0068] 2) Length: indicates the data length of the TLV information;

[0069] 3) Content (Value): The content carried is the synchronization node time cumulative error information (sumTE_node). The number of information bytes can be expanded according to the synchronization accuracy requirements. From the perspective of network accuracy limits and technological development, an 8-byte data storage solution can be adopted, and the data accuracy unit is set to 2-16ns;

[0070] In addition, the time accuracy information of the time source can also be transmitted in the above-mentioned notification message and TLV. When the time source node sends the notification message, it needs to correctly fill in the master clock accuracy information (GM_accuracy) according to the standard requirements. As the starting point of the synchronization link, the synchronization node time cumulative error information (sumTE_node) is filled in as "0". Or this information is not carried and is generated by the synchronization node connected to it.

[0071] When the synchronization node forwards the synchronization node time cumulative error information (sumTE_node), the synchronization node time cumulative error information needs to be updated. The update rules are as follows:

[0072] The local time accuracy of forwarding node i (TA_node_i) is added to the synchronization node time cumulative error information (sumTE_node), that is:

[0073] sumTE_node=sumTE_node+TA_node_i;

[0074] The information generated by the first synchronization node connected to the time source is:

[0075] sumTE_node=TA_node_i;

[0076] After the synchronization node time cumulative error information is generated, it is carried in a synchronization announcement message (Announce) and forwarded to downstream nodes along with the announcement message.

[0077] The synchronization link time error information (sumTE_line) is the sum of the accumulated time error brought by the synchronization node in the synchronization link and the master time accuracy information, that is:

[0078] sumTE_line=sumTE_node+GM_accuracy;

[0079] The synchronization link time error information is obtained from the received notification message and calculated, and stored in association with the time source information and the receiving port. It is used for the subsequent synchronization link decision of the synchronization node.

[0080] S3. The downstream node decides the optimal synchronization path and the working status of the node port based on the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node. The working status of the node port includes the master clock state, the slave clock state and the passive clock state.

[0081] It is worth noting that this application can replace the data set comparison algorithm in the optimal master clock algorithm (BMCA) defined by IEEE1588 and G.8275.1, and optimize the synchronization decision in the hybrid networking scenario. Now take two synchronization links as an example to illustrate, the specific scheme is as follows:

[0082] 1) The accumulated error information between the time source and the synchronization node is transmitted through the notification message. When a node receives two or more different notification messages from different ports, it needs to compare them one by one to determine the optimal time source. For the sake of convenience, the received notification message is regarded as a synchronization link. Assume that node i receives a message from synchronization link A at PTP port m and a message from synchronization link B at PTP port n, and decides the pros and cons between synchronization links A and B;

[0083] 2) The first part of the data comparison algorithm of node i is to compare the time source data sets of the synchronization links, and compare the master clock priority 1 (GM_priority1), master clock clock class (GM_class), master clock offset Allan variance (GM_offsetScaledVariance), master clock priority 2 (GM_priority2), and master clock identification (GM_ID) parameters of synchronization links A and B in turn to determine the dominant time source. According to the comparison results, the decision result is that synchronization link A is better than synchronization link B, or synchronization link B is better than synchronization link A. In this patent solution, the first part of the data comparison algorithm, the comparison of synchronization link time source data sets, is different from the traditional solution, and the master clock accuracy (GM_accuracy) is not compared. This data will be used in the second part of the data set comparison algorithm to optimize link decisions. ;

[0084] 3) If the first part of the decision fails to distinguish the advantages and disadvantages of synchronization links A and B, the second part of the decision is to compare the accumulated time error information of the synchronization links. The decision method is as follows:

[0085] A. When the difference between the synchronization link time error of synchronization link A (sumTE_line_A) and the synchronization link time error of synchronization link B (sumTE_line_B) is greater than the time accuracy of node i (TA_node_i), that is:

[0086] sumTE_line_A-sumTE_line_B>TA_node_i;

[0087] The decision result is that synchronization link B is better than synchronization link A.

[0088] B. When the difference between the synchronization link time error of synchronization link B (sumTE_line_B) and the synchronization link time error of synchronization link B (sumTE_line_A) is greater than the time accuracy of node i (TA_node_i), that is:

[0089] sumTE_line_B-sumTE_line_A>TA_node_i;

[0090] The decision result is that synchronization link A is better than synchronization link B.

[0091] C. When the difference between the synchronization link time error of synchronization link A (sumTE_line_A) and the synchronization link time error of synchronization link B (sumTE_line_B) is equal to the time accuracy of node i (TA_node_i), that is:

[0092] sumTE_line_A - sumTE_line_B = TA_node_i;

[0093] The decision result also needs to be associated with the announcement message carrying the information of synchronization link A, and the comparison result between the sending port identification number (portID_sender_A) of the previous synchronization node and the receiving port identification number (portID_receiver_A) of this node. The port identification number is an inherent parameter of the synchronization node. There are specific rules for portID in some standards, and the generated result is a unique ID number. Substantially, comparing the sizes of portID is to compare the sizes of two strings of numbers. The specific decision results are as follows:

[0094] A) When (portID_sender_A > portID_receiver_A), the decision result is that synchronization link B is superior to synchronization link A;

[0095] B) When (portID_sender_A < portID_receiver_A), the decision result is that synchronization link B is logically superior to synchronization link A;

[0096] C) When (portID_sender_A = portID_receiver_A), a decision error is returned. At this time, there is an information error and no decision can be made;

[0097] D. When the difference between the synchronization link time error (sumTE_line_B) of synchronization link B and the synchronization link time error (sumTE_line_A) of synchronization link A is equal to the time accuracy (TA_node_i) of node i, that is:

[0098] sumTE_line_B - sumTE_line_A = TA_node_i;

[0099] The decision result also needs to be associated with the announcement message carrying the information of synchronization link B, and the comparison result between the sending port identification number (portID_sender_B) of the previous synchronization node and the receiving port identification number (portID_receiver_B) of this node. The port identification number is an inherent parameter of the synchronization node. The specific decision results are as follows:

[0100] A) When (portID_sender_B > portID_receiver_B), the decision result is that synchronization link A is superior to synchronization link B;

[0101] B) When (portID_sender_B < portID_receiver_B), the decision result is that synchronization link A is logically superior to synchronization link B;

[0102] C) When (portID_sender_B = portID_receiver_B), a decision error is returned. At this time, there is an information error and no decision can be made;

[0103] E. When the difference between the synchronization link time error (sumTE_line_A) of synchronization link A and the synchronization link time error (sumTE_line_B) of synchronization link B is less than the time accuracy (TA_node_i) of node i and greater than "0", that is:

[0104] 0 <sumTE_line_A-sumTE_line_B<TA_node_i;

[0105] The decision result is that synchronization link B is logically superior to synchronization link A.

[0106] F. When the difference between the synchronization link time error (sumTE_line_B) of synchronization link B and the synchronization link time error (sumTE_line_A) of synchronization link A is less than the time accuracy (TA_node_i) of node i and greater than "0", that is:

[0107] 0 <sumTE_line_B-sumTE_line_A<TA_node_i;

[0108] The decision result is that synchronization link A is logically superior to synchronization link B.

[0109] G. When the difference between the synchronization link time error of synchronization link B (sumTE_line_B) and the synchronization link time error of synchronization link A (sumTE_line_A) is "0", that is:

[0110] sumTE_line_A=sumTE_line_B;

[0111] The decision result also needs to be associated with the comparison result of the port identification number (portID_sender_A) of the previous synchronization node sending the notification message carrying the synchronization link A information and the port identification number (portID_sender_B) of the previous synchronization node sending the notification message carrying the synchronization link B information. The port identification number is an inherent parameter of the synchronization node. The specific decision results are as follows:

[0112] A) When (portID_sender_A>portID_sender_B), the decision result is that synchronization link B is logically superior to synchronization link A;

[0113] B) When (portID_sender_B>portID_sender_A), the decision result is that synchronization link A is logically superior to synchronization link B;

[0114] C) When (portID_sender_B = portID_sender_A), the decision result needs to further compare the synchronization link A information receiving port number (portNum_receiver_A) and the synchronization link B information receiving port number (portNum_receiver_B) of the current synchronization node. The port number is an inherent parameter of the synchronization node. The specific decision results are as follows:

[0115] a. When (portNum_receiver_A>portNum_receiver_B), the decision result is that synchronization link B is logically superior to synchronization link A;

[0116] b. When (portNum_receiver_B>portNum_receiver_A), the decision result is that synchronization link A is logically superior to synchronization link B;

[0117] c. When (portNum_receiver_A = portNum_receiver_B), an error is returned. At this time, there is information error and no decision can be made;

[0118] The above decision results for synchronization links A and B can be directly applied as input data to the original BMCA port decision without revising the original port decision algorithm. For a synchronization node, the synchronization link information received from different ports will be compared one by one to determine the optimal path information. That is, the comparison decision results of this synchronization link information and other synchronization link information are all "excellent" or "logically excellent". The subsequent steps are divided into two steps to determine the port synchronization working status of the decision node:

[0119] 1) The port is the port that receives the optimal synchronization link information and decides that the port works in the slave clock state (Slave);

[0120] 2) For other ports, the received synchronization link information is compared with the optimal synchronization link information of the node. If the optimal path information receiving port compares and decides to be "excellent", the port decides to work in the master clock state (Master); if the optimal path information receiving port compares and decides to be "logically excellent", the port decides to work in the clock blocking state (Passive).

[0121] It is worth noting that when three or more synchronization links need to be selected, it is necessary to first determine the synchronization link with the smallest time error as the reference synchronization link, and then make a pairwise selection for each of the remaining synchronization links and the reference synchronization link in turn according to the above method.

[0122] The above steps are further explained below with reference to specific examples:

[0123] See also Figure 4 As shown in the figure, a synchronization network is composed of time source 1, time source 2, and 4 synchronization nodes. The time accuracy of time source 1 is 20ns; the time accuracy of time source 2 is 30ns; the time accuracy of node 1 and node 2 is 5ns; the time accuracy of node 3 and node 4 is 10ns. The decision-making process of each node in the link is as follows:

[0124] 1. Node 1 receives the notification message sent by time source 1 from the n1p1 port, and the notification message received by the n1p2 port is sent by time source 2 and forwarded by nodes 4, 3, and 2.

[0125] 1) Calculate the synchronization link time error respectively:

[0126] sumTE_line_n1p1=20ns;

[0127] sumTE_line_n1p2=30ns+10ns+10ns+5ns=55ns;

[0128] 2) Compare the results:

[0129] sumTE_line_n1p2-sumTE_line_n1p1=35ns;

[0130] 3) The comparison difference is greater than the synchronization accuracy of node 1 (TA_node_1 = 5ns), and the synchronization link information received by port n1p1 is decided to be better than the synchronization link information received by port n1p2. Based on this decision result, the port state of node 1 is decided as follows: port n1p1 works in slave clock state, and port n1p2 works in master clock state.

[0131] 2. The decision of node 2 is similar to that of node 1:

[0132] 1) Calculate the synchronization link time error as:

[0133] sumTE_line_n2p1=20ns+5ns=25ns;

[0134] sumTE_line_n2p2=30ns+10ns+10ns=50ns;

[0135] 2) Compare the results:

[0136] sumTE_line_n2p2-sumTE_line_n2p1=25ns;

[0137] 3) The comparison difference is greater than the synchronization accuracy of node 2 (TA_node_2 = 5ns), and the synchronization link information received by port n2p1 is decided to be better than the synchronization link information received by port n2p2. Based on this decision result, the port state of node 2 is decided as follows: port n2p1 works in the slave clock state, and port n2p2 works in the master clock state.

[0138] 3. The decision of node 3 is as follows:

[0139] 1) Calculate the synchronization link time error as:

[0140] sumTE_line_n3p1=20ns+5ns+5ns=30ns;

[0141] sumTE_line_n3p2=30ns+10ns=40ns;

[0142] 2) Compare the results:

[0143] sumTE_line_n3p2-sumTE_line_n3p1=10ns;

[0144] 3) The comparison difference is equal to the synchronization accuracy of node 3 (TA_node_3 = 10ns). According to the patent solution, it is necessary to associate and compare the port identification number of the synchronous link information transmission and reception to make a decision:

[0145] a) In this example, sumTE_line_n3p2>sumTE_line_n3p1. According to the solution, the port identification number (n3p2_portID) of the n3p2 port and the port identification number (n4p1_portID) of the corresponding n4p1 port of node 4 need to be obtained. n3p2_portID is an inherent parameter of node 3 and can be queried. n4p1_portID is an inherent parameter of node 4 and is passed to node 3 through a notification message when the n4p1 port sends the synchronization link notification information of time source 2.

[0146] b) The decision results are as follows:

[0147] I. If n3p2_portID>n4p1_portID, the decision result is that sumTE_line_n3p1 is logically superior to sumTE_line_n3p2. Based on this port working state, the decision is: n3p1 port works in the slave clock state, and n3p2 port works in the passive clock state;

[0148] II. If n4p1_portID>n3p2_portID, the decision result is sumTE_line_n3p1 is better than sumTE_line_n3p2. According to this port working state, the decision is: n3p1 port works in the slave clock state, and n3p2 port works in the master clock state;

[0149] III. If n4p1_portID = n3p2_portID, it is determined that there is information error, no decision can be made, and an error message is returned.

[0150] 4. The decision of node 4 is as follows:

[0151] 1) Calculate the synchronization link time error as:

[0152] sumTE_line_n4p1=20ns+5ns+5ns+10ns=40ns;

[0153] sumTE_line_n4p2=30ns;

[0154] 2) Compare the results:

[0155] sumTE_line_n4p1-sumTE_line_n4p2=10ns;

[0156] 3) The comparison difference is equal to the synchronization accuracy of node 4 (TA_node_4 = 10ns). According to the patent solution, it is necessary to associate and compare the port identification number of the synchronous link information transmission and reception to make a decision:

[0157] a) In this example, sumTE_line_n4p1>sumTE_line_n4p2. According to the solution, the port identification number (n4p1_portID) of the n4p1 port and the port identification number (n3p2_portID) of the n3p2 port of the corresponding node 3 need to be obtained. n4p1_portID is an inherent parameter of node 4 and can be queried. n3p2_portID is an inherent parameter of node 3 and is passed to node 4 through a notification message when the n3p2 port sends the synchronization link notification information of time source 1.

[0158] b) The decision results are as follows:

[0159] I. If n4p1_portID>n3p2_portID, the decision result is that sumTE_line_n4p2 is logically superior to sumTE_line_n4p1. Based on this port working state, the decision is: n4p2 port works in the slave clock state, and n4p1 port works in the passive clock state;

[0160] II. If n3p2_portID>n4p1_portID, the decision result is sumTE_line_n4p2 is better than sumTE_line_n4p1. According to this port working state, the decision is: n4p2 port works in the slave clock state, and n4p1 port works in the master clock state;

[0161] III. If n4p1_portID = n3p2_portID, it is determined that there is information error, no decision can be made, and an error message is returned.

[0162] From the decision result, node 1, node 2, and node 3 choose to track time source 1, and node 4 chooses to track time source 2, all of which choose a synchronization link with a relatively small error from the node perspective. In addition, other scenarios can also implement decisions according to the solution of this application.

[0163] In summary, the hybrid networking synchronization path decision method in the present application calibrates the time accuracy information of the time source and the synchronization node; transmits the time accuracy information of the time source and the time cumulative error information of the synchronization node to the downstream node; the downstream node decides the optimal synchronization path and the working state of the node port according to the time accuracy information of the time source, the time cumulative error information of the synchronization node, and the local time accuracy information of the node, and the working state of the node port includes the master clock state, the slave clock state and the passive clock state. Thus, it is possible to adapt to time sources and synchronization nodes with different time accuracy, and in a hybrid networking scenario, it is possible to decide to select the optimal path with the smallest time error, and there is no restriction on the time accuracy of the time source and the synchronization node, and it is compatible with the synchronization accuracy of existing devices, and it can also adapt to subsequent devices with higher synchronization accuracy.

[0164] In a second aspect, an embodiment of the present application also provides a hybrid networking synchronization path decision device.

[0165] In one embodiment, referring to Figure 5 , Figure 5 This is a functional module diagram of an embodiment of a hybrid networking synchronization path decision device of the present application. Figure 5 As shown, the hybrid networking synchronization path decision device includes:

[0166] A calibration module, which is used to calibrate the time accuracy information of the time source and the synchronization node;

[0167] A transmission module, which is used to transmit the time accuracy information of the time source and the accumulated error information of the synchronization node time to the downstream node;

[0168] A decision module is used to decide the optimal synchronization path and the working state of the node port at the downstream node according to the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node. The working state of the node port includes the master clock state, the slave clock state and the passive clock state.

[0169] Further, in one embodiment, the decision module is used to decide the optimal synchronization path and the working state of the node port at the downstream node according to the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node, including:

[0170] Determine the synchronization link time error of each synchronization link corresponding to the downstream node according to the time accuracy of the time source and the sum of the synchronization node time cumulative error;

[0171] The synchronization link with the smallest synchronization link time error is taken as the optimal synchronization path;

[0172] The difference between the synchronization link time error of each synchronization link and the optimal synchronization path is calculated, and the difference is compared with the local time accuracy information of the downstream node to determine the working status of the node port.

[0173] Further, in one embodiment, the decision module calculates the difference between the synchronization link time error of each synchronization link and the reference synchronization link, compares the difference with the local time accuracy information of the downstream node, and decides the working state of the optimal synchronization path and the node port, including:

[0174] If the difference is greater than the local time accuracy information of the downstream node, the reference synchronization link is determined to be the optimal synchronization path and is determined to be superior to the compared synchronization link;

[0175] In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link involved in the comparison, if the decision result is excellent, the port that decides to receive the synchronization link information works in the master clock state.

[0176] Further, in one embodiment, the decision module calculates the difference between the synchronization link time error of each synchronization link and the reference synchronization link, compares the difference with the local time accuracy information of the downstream node, and decides the working state of the optimal synchronization path and the node port, and also includes:

[0177] If the difference is equal to the local time accuracy information of the downstream node, further determine the size of the sending port identification number of the previous synchronization node and the receiving port identification number of the current node of the synchronization link to be compared;

[0178] If the sending port identification number is greater than the receiving port identification number, the reference synchronization link is determined to be the optimal synchronization path and is determined to be superior to the compared synchronization link;

[0179] If the sending port identification number is smaller than the receiving port identification number, the reference synchronization link is determined to be the optimal synchronization path, and the decision logic is superior to the compared synchronization link, and the reference synchronization link will be blocked by the compared synchronization link;

[0180] If the sending port identification number is equal to the receiving port identification number, a decision error is returned;

[0181] In the downstream node, the port that decides to receive the optimal synchronization path information operates in the slave clock state. For the synchronization link participating in the comparison, if the decision result is optimal, the port that decides to receive the synchronization link information operates in the master clock state. If the decision result is logically optimal, the port that decides to receive the synchronization link information operates in the passive clock state.

[0182] Further, in one embodiment, the decision module calculates the difference between the synchronization link time error of each synchronization link and the reference synchronization link, compares the difference with the local time accuracy information of the downstream node, and decides the working state of the optimal synchronization path and the node port, and also includes:

[0183] If the difference is greater than zero but less than the local time accuracy information of the downstream node, the reference synchronization link is determined to be the optimal synchronization path, and the decision logic is better than the compared synchronization link, and the reference synchronization link will be blocked by the compared synchronization link;

[0184] In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link participating in the comparison, if the decision result is logically excellent, the port that decides to receive the synchronization link information works in the passive clock state.

[0185] Further, in one embodiment, the decision module calculates the difference between the synchronization link time error of each synchronization link and the reference synchronization link, compares the difference with the local time accuracy information of the downstream node, and decides the working state of the optimal synchronization path and the node port, and also includes:

[0186] If the difference is zero, then further compare the reference synchronization link and the comparison synchronization link at the previous synchronization node.

[0187] If the sending port identification numbers are different, the synchronization link with the smaller sending port identification number is determined to be the optimal synchronization path, and the determination logic is better than the other synchronization link for comparison, the synchronization link as the optimal synchronization path will block the other synchronization link for comparison;

[0188] If the sending port identification numbers are the same, then further comparing the receiving port numbers of the reference synchronization link and the synchronization link to be compared at the previous synchronization node;

[0189] If the receiving port numbers are different, the synchronization link with the smaller receiving port number is determined to be the optimal synchronization path, and the determination logic is better than the other synchronization link for comparison, the synchronization link as the optimal synchronization path will block the other synchronization link for comparison;

[0190] If the receiving port numbers are the same, a decision error is returned;

[0191] In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link participating in the comparison, if the decision result is logically excellent, the port that decides to receive the synchronization link information works in the passive clock state.

[0192] Furthermore, in one embodiment, the transmission module is used to:

[0193] The time accuracy information of the time source and the accumulated error information of the synchronization node time are transmitted through notification messages or TLV information.

[0194] Furthermore, in one embodiment, the calibration module determines the time accuracy information of the synchronization node by reading relevant inherent characteristic information when the device is implemented.

[0195] Among them, the functional implementation of each module in the above-mentioned hybrid networking synchronization path decision device corresponds to the various steps in the above-mentioned hybrid networking synchronization path decision method embodiment, and its functions and implementation processes will not be repeated here one by one.

[0196] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0197] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0198] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0199] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0200] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0201] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0202] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A hybrid networking synchronization path decision method, characterized in that: The hybrid networking synchronization path decision method comprises: Calibrate the time accuracy information of the time source and synchronization node; Transmit the time accuracy information of the time source and the accumulated error information of the synchronization node time to the downstream nodes; The downstream node decides the optimal synchronization path and the working status of the node port based on the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node. The working status of the node port includes the master clock state, the slave clock state and the passive clock state.

2. The hybrid networking synchronization path decision method according to claim 1, characterized in that: The downstream node determines the optimal synchronization path and the working state of the node port according to the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node, including: Determine the synchronization link time error of each synchronization link corresponding to the downstream node according to the time accuracy of the time source and the sum of the synchronization node time cumulative error; Select the synchronization link with the smallest time error as the reference synchronization link; The difference between the synchronization link time error of each synchronization link and the reference synchronization link is calculated, and the difference is compared with the local time accuracy information of the downstream node to determine the optimal synchronization path and the working status of the node port.

3. The hybrid networking synchronization path decision method according to claim 2, characterized in that: The step of calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and determining the optimal synchronization path and the working state of the node port includes: If the difference is greater than the local time accuracy information of the downstream node, the reference synchronization link is determined to be the optimal synchronization path and is determined to be superior to the compared synchronization link; In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link involved in the comparison, if the decision result is excellent, the port that decides to receive the synchronization link information works in the master clock state.

4. The hybrid networking synchronization path decision method according to claim 2, characterized in that: The step of calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and determining the optimal synchronization path and the working state of the node port includes: If the difference is equal to the local time accuracy information of the downstream node, further determine the size of the sending port identification number of the previous synchronization node and the receiving port identification number of the current node of the synchronization link to be compared; If the sending port identification number is greater than the receiving port identification number, the reference synchronization link is determined to be the optimal synchronization path and is determined to be superior to the compared synchronization link; If the sending port identification number is smaller than the receiving port identification number, the reference synchronization link is determined to be the optimal synchronization path, and the decision logic is superior to the compared synchronization link, and the reference synchronization link will be blocked by the compared synchronization link; If the sending port identification number is equal to the receiving port identification number, a decision error is returned; In the downstream node, the port that decides to receive the optimal synchronization path information operates in the slave clock state. For the synchronization link participating in the comparison, if the decision result is optimal, the port that decides to receive the synchronization link information operates in the master clock state. If the decision result is logically optimal, the port that decides to receive the synchronization link information operates in the passive clock state.

5. The hybrid networking synchronization path decision method according to claim 2, characterized in that: The step of calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and determining the optimal synchronization path and the working state of the node port includes: If the difference is greater than zero but less than the local time accuracy information of the downstream node, the reference synchronization link is determined to be the optimal synchronization path, and the decision logic is better than the compared synchronization link, and the reference synchronization link will be blocked by the compared synchronization link; In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link participating in the comparison, if the decision result is logically excellent, the port that decides to receive the synchronization link information works in the passive clock state.

6. The hybrid networking synchronization path decision method according to claim 2, characterized in that: The step of calculating the difference between the synchronization link time error of each synchronization link and the reference synchronization link, comparing the difference with the local time accuracy information of the downstream node, and determining the optimal synchronization path and the working state of the node port includes: If the difference is zero, then further compare the reference synchronization link and the comparison synchronization link at the previous synchronization node. If the sending port identification numbers are different, the synchronization link with the smaller sending port identification number is determined to be the optimal synchronization path, and the determination logic is better than the other synchronization link for comparison, the synchronization link as the optimal synchronization path will block the other synchronization link for comparison; If the sending port identification numbers are the same, then further comparing the sizes of the receiving port numbers of the reference synchronization link and the synchronization link to be compared at the current synchronization node; If the receiving port numbers are different, the synchronization link with the smaller receiving port number is determined to be the optimal synchronization path, and the determination logic is better than the other synchronization link for comparison, the synchronization link as the optimal synchronization path will block the other synchronization link for comparison; If the receiving port numbers are the same, a decision error is returned; In the downstream node, the port that decides to receive the optimal synchronization path information works in the slave clock state. For the synchronization link participating in the comparison, if the decision result is logically excellent, the port that decides to receive the synchronization link information works in the passive clock state.

7. The hybrid networking synchronization path decision method according to claim 1, characterized in that: The time accuracy information of the time source and the accumulated error information of the synchronization node time are transmitted through notification messages or TLV information.

8. The hybrid networking synchronization path decision method according to claim 1, characterized in that: Read the relevant inherent characteristic information of the device implementation to determine the time accuracy information of the synchronization node.

9. A hybrid networking synchronization path decision device, characterized in that: The hybrid networking synchronization path decision device comprises: A calibration module, which is used to calibrate the time accuracy information of the time source and the synchronization node; A transmission module, which is used to transmit the time accuracy information of the time source and the accumulated error information of the synchronization node time to the downstream node; A decision module is used to decide the optimal synchronization path and the working state of the node port at the downstream node according to the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node. The working state of the node port includes the master clock state, the slave clock state and the passive clock state.

10. The hybrid networking synchronization path decision device according to claim 9, characterized in that: The decision module is used to decide the optimal synchronization path and the working state of the node port at the downstream node according to the time accuracy information of the time source, the accumulated error information of the synchronization node time, and the local time accuracy information of the node, including: Determine the synchronization link time error of each synchronization link corresponding to the downstream node according to the time accuracy of the time source and the sum of the synchronization node time cumulative error; The synchronization link with the smallest synchronization link time error is taken as the optimal synchronization path; The difference between the synchronization link time error of each synchronization link and the optimal synchronization path is calculated, and the difference is compared with the local time accuracy information of the downstream node to determine the working status of the node port.

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