Method and apparatus for measuring latency, storage medium, program product

Abstract

This application discloses a latency measurement method, apparatus, storage medium, and program product. The latency measurement method includes: acquiring target time information carried in a first latency measurement message, wherein the target time information includes first time information filled by intermediate nodes along the transmission path and second time information filled by the destination node; acquiring the unidirectional link cumulative latency from the source node to the destination node based on the first and second time information; and sending a second latency measurement message including the unidirectional link cumulative latency to the destination node, so that the destination node can acquire the unidirectional latency from the source node to the destination node based on the unidirectional link cumulative latency. In the embodiments of this application, reliable measurement of unidirectional latency can be achieved without time synchronization, improving the accuracy of unidirectional latency measurement, thereby filling the technical gaps in related methods.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a delay measurement method and apparatus, a computer storage medium, and a computer program product. Background Technology

[0002] To provide better service to customers and facilitate network operation and maintenance, telecom operators need to monitor end-to-end performance indicators of the network and services, such as latency, jitter, packet loss rate, and throughput. Latency measurement is divided into one-way latency measurement and round-trip latency measurement. Since many critical services are one-way services with asymmetrical round-trip latency, one-way latency measurement can more accurately reflect the network service status, such as whether congestion has occurred. Therefore, accurate measurement of one-way latency is particularly important. Currently, the implementation of various one-way latency measurement mechanisms relies on time synchronization. With time synchronization, one-way latency can be obtained simply by marking specific packets with sequence numbers or coloring techniques and performing relevant calculations. However, the requirement of time synchronization cannot be met in many scenarios. For example, using GPS time synchronization is not suitable for deploying servers in data centers, basements, or caves. The 1588 clock protocol also has the disadvantage of limited adaptability and is not suitable for large-scale network deployment, making it impossible to ensure the measurement of one-way latency. Summary of the Invention

[0003] This application provides a delay measurement method and apparatus, a computer storage medium, and a computer program product, which can reliably measure unidirectional delay without time synchronization.

[0004] In a first aspect, embodiments of this application provide a time delay measurement method, the time delay measurement method comprising:

[0005] Obtain the target time information carried in the first delay measurement message, wherein the target time information includes first time information filled by intermediate nodes on the transmission path and second time information filled by the destination node, the first time information is used to obtain the dwell time of the first delay measurement message at the intermediate node, and the second time information is used to obtain the dwell time of the first delay measurement message at the destination node.

[0006] The cumulative one-way link delay from the source node to the destination node is obtained based on the first time information and the second time information.

[0007] A second delay measurement message including the one-way link accumulated delay is sent to the destination node so that the destination node can obtain the one-way delay from the source node to the destination node based on the one-way link accumulated delay.

[0008] Secondly, embodiments of this application also provide a time delay measurement device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the time delay measurement method as described above.

[0009] Thirdly, embodiments of this application also provide a computer-readable storage medium storing computer-executable instructions for performing the time delay measurement method as described above.

[0010] Fourthly, embodiments of this application also provide a computer program product, wherein the computer program or the computer instructions are stored in a computer-readable storage medium, the processor of a computer device reads the computer program or the computer instructions from the computer-readable storage medium, and the processor executes the computer program or the computer instructions to cause the computer device to perform the delay measurement method as described above.

[0011] In this embodiment, by acquiring the first time information filled by the intermediate node and the second time information filled by the destination node carried in the first delay measurement message traveling between the source node and the destination node, that is, by determining the dwell time of the first delay measurement message at the intermediate node and the destination node, the one-way cumulative delay from the source node to the destination node can be obtained based on the first time information and the second time information. Then, by sending a second delay measurement message including the acquired one-way cumulative delay to the destination node, the one-way delay from the source node to the destination node is determined. Since the acquisition of the one-way cumulative delay or the one-way delay involved in the measurement process is performed within the relevant nodes, that is, it is not necessary to achieve time synchronization between the nodes. Instead, the relevant nodes accurately and reliably obtain the final one-way delay according to the actual delay scenario. Therefore, this embodiment can achieve reliable measurement of one-way delay without time synchronization, improve the measurement accuracy of one-way delay, and thus fill the technical gap in related methods. Attached Figure Description

[0012] Figure 1 This is a flowchart of a time delay measurement method provided in one embodiment of this application;

[0013] Figure 2 This is a flowchart illustrating the acquisition of target time information in a time delay measurement method provided in one embodiment of this application;

[0014] Figure 3 This is a flowchart illustrating the acquisition of target time information in a time delay measurement method provided in another embodiment of this application;

[0015] Figure 4This is a flowchart illustrating the process of obtaining the cumulative one-way link delay from the source node to the destination node in a delay measurement method provided in one embodiment of this application.

[0016] Figure 5 This is a schematic diagram illustrating the principle of a time delay measurement method provided in one embodiment of this application;

[0017] Figure 6 This is a schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application;

[0018] Figure 7 This is a schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application;

[0019] Figure 8 This is a schematic diagram illustrating an application scenario of the time delay measurement method provided in one embodiment of this application;

[0020] Figure 9 This is a flowchart illustrating the process of obtaining the cumulative one-way link delay from the source node to the destination node in a delay measurement method provided in another embodiment of this application;

[0021] Figure 10 This is a schematic diagram illustrating an application scenario of the time delay measurement method provided in one embodiment of this application;

[0022] Figure 11 This is a flowchart illustrating the process of sending a second delay measurement message, including the cumulative delay of a one-way link, to a destination node in a delay measurement method provided in one embodiment of this application.

[0023] Figure 12 This is a flowchart of a delay measurement method provided in another embodiment of this application, in which a second delay measurement message including the cumulative delay of a one-way link is sent to the destination node;

[0024] Figure 13 This is a schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application;

[0025] Figure 14 This is a schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application;

[0026] Figure 15 This is a schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application;

[0027] Figure 16 This is a schematic diagram of the encapsulation of the fields required by the delay measurement method provided in one embodiment of this application in the OAM protocol measurement message;

[0028] Figure 17 This is a schematic diagram of a time delay measurement device provided in one embodiment of this application. Detailed Implementation

[0029] To make the objectives, technical methods, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0030] It should be noted that although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than that shown in the flowchart. The terms "first," "second," etc., in the specification, claims, and the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0031] Currently, because time-synchronization-based one-way delay measurement mechanisms cannot be applied in many scenarios, research is constantly being conducted on one-way delay measurement techniques without time synchronization. For example, one approach is to assume that the round-trip delay on the transmission path is equal, and then divide the round-trip delay by two to obtain the one-way delay. However, this assumption only holds true in a few environments where network traffic is controllable (such as industrial LANs) and is not applicable to all network scenarios. Another approach is to analyze the one-way transmission delay of a reference message and correlate its theoretical value with the actual value. The disadvantage of this approach is that in most scheduling mechanisms and business scenarios, due to jitter in the reference message, the theoretical value of the reference message may not be accurately determined. Yet another approach is to assume that other delays besides queuing delay are constant and apply algorithms such as differential fitting to estimate the queuing delay. However, this approach often suffers from problems such as large estimation errors.

[0032] Based on this, this application provides a latency measurement method and apparatus, a computer storage medium, and a computer program product. One embodiment of the latency measurement method includes: acquiring target time information carried in a first latency measurement message, wherein the target time information includes first time information filled by intermediate nodes along the transmission path and second time information filled by the destination node; the first time information is used to acquire the dwell time of the first latency measurement message at the intermediate nodes, and the second time information is used to acquire the dwell time of the first latency measurement message at the destination node; acquiring the unidirectional link cumulative latency from the source node to the destination node based on the first time information and the second time information; and sending a second latency measurement message including the unidirectional link cumulative latency to the destination node, so that the destination node acquires the unidirectional latency from the source node to the destination node based on the unidirectional link cumulative latency. In this embodiment, by acquiring the first time information filled by the intermediate node and the second time information filled by the destination node carried in the first delay measurement message traveling between the source node and the destination node, that is, by determining the dwell time of the first delay measurement message at the intermediate node and the destination node, the one-way cumulative delay from the source node to the destination node can be obtained based on the first time information and the second time information. Then, by sending a second delay measurement message including the acquired one-way cumulative delay to the destination node, the one-way delay from the source node to the destination node is determined. Since the acquisition of the one-way cumulative delay or the one-way delay involved in the measurement process is performed within the relevant nodes, that is, it is not necessary to achieve time synchronization between the nodes. Instead, the relevant nodes accurately and reliably obtain the final one-way delay according to the actual delay scenario. Therefore, this embodiment can achieve reliable measurement of one-way delay without time synchronization, improve the measurement accuracy of one-way delay, and thus fill the technical gap in related methods.

[0033] The embodiments of this application will be further described below with reference to the accompanying drawings.

[0034] like Figure 1 As shown, Figure 1 This is a flowchart of a time delay measurement method provided in one embodiment of this application. The time delay measurement method may include, but is not limited to, steps S110 to S130.

[0035] Step S110: Obtain the target time information carried by the first delay measurement message, wherein the target time information includes the first time information filled by the intermediate nodes on the transmission path and the second time information filled by the destination node. The first time information is used to obtain the dwell time of the first delay measurement message at the intermediate node, and the second time information is used to obtain the dwell time of the first delay measurement message at the destination node.

[0036] In this step, by obtaining the first time information filled by the intermediate node and the second time information filled by the destination node carried in the first delay measurement message traveling between the source node and the destination node, that is, by determining the dwell time of the first delay measurement message relative to the intermediate node and the destination node, the cumulative delay of the one-way link from the source node to the destination node can be obtained in subsequent steps based on the first time information and the second time information.

[0037] In one embodiment, the distinction between the source node, intermediate node, and destination node is based solely on their specific functions in the transmission path. That is, the source node, as the source node in the transmission path, the intermediate node, as the intermediate node in the transmission path, has the function of filling in the first time information, and the destination node, as the destination node in the transmission path, has the function of filling in the second time information. As for the specific parameters, content, and application methods of the source node, intermediate node, and destination node, those skilled in the art can make corresponding settings according to the specific scenario, and there are no limitations here.

[0038] In one embodiment, the specific types of the source node, intermediate node, and destination node can be various, and are not limited here. For example, any one of the source node, intermediate node, and destination node can be, but is not limited to, a transmitting terminal, an access terminal, a modulator, and a service unit, etc. When it is a transmitting terminal or an access terminal, it can be, but is not limited to, a user equipment (UE), a user unit, a user station, a mobile station, a mobile station, a remote station, a remote terminal, a mobile device, a user terminal, a wireless communication device, a user agent, or a user device, etc.

[0039] In one embodiment, the intermediate nodes may be one or more in a specific application scenario, but regardless of their number, they can all be used to fill the first time information. That is to say, the first time information included in the target time information may be one or more, which is not limited here, and does not affect its calculation of the cumulative delay of the one-way link.

[0040] In one embodiment, the type and content of the first delay measurement message can be set according to the specific scenario. The transmission path can be, but is not limited to, the target path used in the corresponding scenario, or other transmission paths with similar or nearly identical characteristics to the target path, etc., which are not limited here.

[0041] like Figure 2 As shown in the embodiment of this application, step S110 is further described. Step S110 includes, but is not limited to, steps S111 to S113.

[0042] Step S111: Send a first delay measurement message including a loopback marker to the destination node;

[0043] Step S112: Receive the first delay measurement message returned by the destination node according to the loopback mark. When the first delay measurement message resides in the intermediate node and the destination node on the transmission path, the intermediate node fills the first delay measurement message with the first time information, and the destination node fills the first delay measurement message with the second time information.

[0044] Step S113: Obtain target time information, including first time information and second time information, from the first time delay measurement message.

[0045] In this step, since the first delay measurement message carries a loopback marker, when the destination node receives the sent first delay measurement message, it can return the first delay measurement message to the source node according to the loopback marker. When the first delay measurement message resides at the intermediate node and the destination node on the transmission path, the intermediate node fills the first delay measurement message with the first time information, and the destination node fills the first delay measurement message with the second time information. Therefore, the first delay measurement message returned to the source node stores the first time information and the second time information, so that the target time information including the first time information and the second time information can be obtained from the returned first delay measurement message.

[0046] In one embodiment, the specific methods for sending a first delay measurement message including a loopback marker to the destination node and receiving the first delay measurement message returned by the destination node according to the loopback marker can be varied and are not limited here. For example, but not limited to: sending a first delay measurement message including a loopback marker to the destination node along the transmission path and receiving the first delay measurement message returned by the destination node along the transmission path according to the loopback marker, with intermediate nodes and the destination node set on the transmission path, that is, by sending the first delay measurement message on the transmission path and simultaneously receiving the first delay measurement message returned along the transmission path, the overall measurement of the first delay measurement message can be achieved, and the target time information including first time information and second time information can be reliably obtained when the first delay measurement message and the transmission path are coordinated. In one embodiment, using a loopback marker can ensure that the target node clearly and reliably returns the first delay measurement message along the original transmission path, thereby obtaining relevant information for calculating the cumulative delay of the one-way link from the returned first delay measurement message, which is beneficial to improving the stability of delay measurement; it is understood that the loopback marker is a communication medium well known to those skilled in the art, and will not be described in detail here.

[0047] One embodiment of this application further describes step S111, which includes, but is not limited to, step S1111.

[0048] Step S1111: Send a first delay measurement message, including a loopback marker, to the destination node along the transmission path.

[0049] In this step, considering that the transmission path and service conditions do not change, the unidirectional link cumulative delay corresponding to sending multiple first delay measurement messages is the same. That is to say, the measurement effect of sending the first delay measurement message each time is roughly the same. Therefore, in order to reduce the measurement workload, it is only necessary to send the first delay measurement message including the loopback mark once, which can improve the delay measurement efficiency. However, in order to improve the delay measurement accuracy, it is also possible to use the method of sending multiple first delay measurement messages including the loopback mark for measurement, which is not limited in this embodiment.

[0050] like Figure 3 As shown in one embodiment of this application, when the target time information also includes a first sending timestamp and a first receiving timestamp filled by the source node, step S113 is further described. Step S113 includes, but is not limited to, step S1131.

[0051] Step S1131: Obtain target time information including first time information, second time information, first sending timestamp and first receiving timestamp from the first delay measurement message.

[0052] In this step, since the first sending timestamp and the first receiving timestamp filled by the source node can respectively characterize the time when the source node sends the first delay measurement message and the time when it receives the first delay measurement message, that is, it can be reflected in the overall time of the round trip of the measurement message on the transmission path. Therefore, it can be used as the target time information. That is, by combining the delay information of the subsequent nodes such as the first time information and the second time information, the cumulative delay of the one-way link from the source node to the destination node can be calculated, which is beneficial to improving the accuracy of delay measurement.

[0053] In one embodiment, the timing of filling the first sending timestamp and the first receiving timestamp corresponds to the transmission status of the first delay measurement message on the transmission path. For example, when the transmission of the first delay measurement message to the exit of the source node is detected, the first sending timestamp is filled at this time; when the transmission of the first delay measurement message to the entry of the source node is detected, the first receiving timestamp is filled at this time.

[0054] Step S120: Obtain the cumulative one-way link delay from the source node to the destination node based on the first time information and the second time information.

[0055] In this step, since the first time information filled by the intermediate nodes on the transmission path and the second time information filled by the destination node have been determined in step S110, that is, the dwell time of the intermediate nodes and the destination node on the transmission path has been determined, the one-way link cumulative delay from the source node to the destination node can be obtained based on the first time information and the second time information, so that the one-way delay from the source node to the destination node can be calculated by the destination node based on the one-way link cumulative delay in subsequent steps.

[0056] One embodiment of this application further illustrates step S120, which includes, but is not limited to, step S121.

[0057] Step S121: Send the first time information and the second time information to the network controller so that the network controller can obtain the cumulative one-way link delay from the source node to the destination node based on the first time information and the second time information.

[0058] In this step, since the network controller can perform real-time management based on the background, that is, the network controller has a high degree of intelligence and has sufficient and complete background operation functions, including calculation and coordination, the first time information and the second time information are sent to the network controller so that the network controller can accurately and reliably obtain the one-way link cumulative delay from the source node to the destination node based on the first time information and the second time information. This can eliminate the trouble of calculating the one-way link cumulative delay through other channels and is conducive to obtaining more accurate delay measurement results.

[0059] In one embodiment, the type of network controller can be various and is not limited here. For example, the network controller can be, but is not limited to, a network interface card (NIC). A NIC is computer hardware that allows computers to communicate on a computer network. It has a MAC address, enabling users to connect to each other via cable or wirelessly. The NIC can house a processor and memory (including RAM and ROM). Communication between the NIC and the local area network (LAN) can be serial via cable or twisted pair, while communication between the NIC and the computer can be parallel via the I / O bus on the computer motherboard. In other words, the NIC can perform serial / parallel conversion, and the data rate on the network and the data rate on the computer bus may differ. Therefore, the NIC can store data rates using a data caching memory chip for later retrieval.

[0060] One embodiment of this application further describes step S120, which includes, but is not limited to, step S122.

[0061] Step S122: Based on the first time information, the second time information, the first sending timestamp, and the first receiving timestamp, obtain the cumulative one-way link delay from the source node to the destination node.

[0062] In this step, since the first sending timestamp and the first receiving timestamp filled by the source node can respectively characterize the time when the source node sends the first delay measurement message and the time when it receives the first delay measurement message, that is, it can be reflected in the overall time of the round trip of the measurement message on the transmission path. Therefore, when it is used as the target time information, the delay information such as the first time information and the second time information can be combined to obtain the unidirectional link cumulative delay from the source node to the destination node, which is beneficial to improving the accuracy of delay measurement.

[0063] like Figure 4 As shown, in one embodiment of this application, when the first time information includes a first entry timestamp and a first exit timestamp, and the second time information includes a second entry timestamp and a second exit timestamp, step S122 is further described. Step S122 includes, but is not limited to, step S1221.

[0064] Step S1221: Based on the difference between the first exit timestamp and the first entry timestamp, the difference between the second exit timestamp and the second entry timestamp, and the difference between the first receiving timestamp and the first sending timestamp, obtain the cumulative one-way link delay from the source node to the destination node.

[0065] In this step, since the difference between the first exit timestamp and the first entry timestamp represents the overall round-trip time of the measurement message on the transmission path, the difference between the second exit timestamp and the second entry timestamp represents the dwell time of the first delay measurement message at the intermediate node on the transmission path, and the difference between the first receive timestamp and the first send timestamp represents the dwell time of the first delay measurement message at the destination node on the transmission path, it can be determined that the other times in the overall round-trip time excluding the relevant dwell time are the corresponding one-way cumulative delay from the source node to the destination node on the transmission path, thus the one-way cumulative delay from the source node to the destination node can be accurately obtained.

[0066] In one embodiment, the cumulative one-way link delay from the source node to the destination node can be obtained in the following manner, but is not limited to: the cumulative one-way link delay is equal to the difference between the first exit timestamp and the first entry timestamp, minus the difference between the second exit timestamp and the second entry timestamp, minus the difference between the first receive timestamp and the first send timestamp, and finally divided by two.

[0067] In one embodiment, the timing of filling the first exit timestamp and the first entry timestamp, and the timing of filling the second exit timestamp and the second entry timestamp, correspond to the transmission status of the first delay measurement message on the transmission path. For example, when the first delay measurement message is detected to be transmitted to the entry of an intermediate node, the first entry timestamp is filled at this time; when the first delay measurement message is detected to be transmitted to the exit of an intermediate node, the first exit timestamp is filled at this time; the same applies when the first delay measurement message returns on the transmission path. When the first delay measurement message is detected to be transmitted to the entry of a destination node, the second entry timestamp is filled at this time; when the first delay measurement message is detected to be transmitted to the exit of a destination node, the second exit timestamp is filled at this time; the same applies when the first delay measurement message returns on the transmission path.

[0068] The following are several specific examples to illustrate the working principles and processes of the above embodiments.

[0069] Example 1:

[0070] like Figure 5 As shown, Figure 5 This is a schematic diagram illustrating the principle of a time delay measurement method provided in one embodiment of this application.

[0071] Reference Figure 5 Source node A sends a first delay measurement message with a loopback or round-trip marker to destination node C. The first delay measurement message is sent back to source node A from destination node C via the reverse path. When the first delay measurement message is sent from or received from a port, a timestamp is added to the first delay measurement message. That is, during the charging process of the first delay measurement message from source node A to destination node C, a timestamp t1 is added at the exit of source node A, an entry timestamp t2 and an exit timestamp t3 are added at intermediate node B, and an entry timestamp t4 is added at destination node C. Similarly, during the process of the first delay measurement message being sent back to source node A, timestamps t5, t6, t7 and t8 are added at the corresponding nodes C, B and A in the same way. The processing delays of the round-trip directions of intermediate nodes are allowed to be inconsistent. For example, at intermediate node B, t7-t6 ≠ t3-t2.

[0072] Assuming that the delay of the link portion in the transmission path is symmetrical, the cumulative delay L of the one-way link is... 1DM It can be calculated using the following formula:

[0073] L 1DM =((t8-t1)-(t3-t2)-(t5-t4)-(t7-t6)) / 2;

[0074] As can be seen from the above example, since the subtraction operation involving all timestamps is performed within the relevant nodes, there is no need for time synchronization between nodes. In other words, reliable measurement of the cumulative delay of a one-way link can be achieved without time synchronization, thereby improving the measurement accuracy of the cumulative delay of a one-way link and filling the technical gap in related methods.

[0075] Example 2:

[0076] like Figure 6 As shown, Figure 6 A schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application.

[0077] Reference Figure 6 Node A is the source node, node B is intermediate node 1, node C is intermediate node 2, and node D is the destination node. If the round-trip time of the first delay measurement message is consistent across all nodes, then:

[0078] Node A -> Node D direction: Node A's exit timestamp is 0, Node B's entry and exit timestamps are 2 and 3 respectively, Node C's entry and exit timestamps are 4 and 6 respectively, and Node D's entry timestamp is 7.

[0079] Node D -> Node A direction: Node D's exit timestamp is 9, Node C's entry and exit timestamps are 10 and 12, Node B's entry and exit timestamps are 13 and 14, and Node A's entry timestamp is 16.

[0080] Then, the one-way link cumulative delay L calculated by node A based on the first delay measurement message. 1DM for:

[0081] L 1DM =(16-0-(3-2)-(6-4)-(9-7)-(12-10)-(14-13)) / 2=4.

[0082] Example 3:

[0083] like Figure 7 As shown, Figure 7 A schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application.

[0084] Reference Figure 7 Node A is the source node, node B is intermediate node 1, node C is intermediate node 2, and node D is the destination node. If the round-trip time of the first delay measurement message is consistent across all nodes, then:

[0085] Node A -> Node D direction: Node A's exit timestamp is 0, Node B's entry and exit timestamps are 2 and 3 respectively, Node C's entry and exit timestamps are 4 and 6 respectively, and Node D's entry timestamp is 7.

[0086] Node D -> Node A direction: Node D's exit timestamp is 9, Node C's entry and exit timestamps are 11 and 14, Node B's entry and exit timestamps are 13 and 15, and Node A's entry timestamp is 18.

[0087] Then, the one-way link cumulative delay L calculated by node A based on the first delay measurement message. 1DM for:

[0088] L 1DM =(18-0-(3-2)-(6-4)-(9-7)-(14-11)-(15-13)) / 2=4;

[0089] As can be seen from this example in conjunction with Example 2, regardless of whether the round-trip delay of the first delay measurement message is consistent within the node, the cumulative delay of the one-way link can be calculated correctly, and the cumulative delay values ​​of the one-way link obtained in each instance are completely equal. Therefore, compared with related technologies, the embodiments of this application do not require the delays in the round-trip direction on the transmission path to be equal. In other words, even if the delays in the round-trip direction on the transmission path are not equal, the embodiments of this application can still be applied, which greatly broadens the applicable network scenarios.

[0090] like Figure 8 As shown, in one embodiment of this application, when the source node stores the second sending timestamp when sending the first delay measurement message and the second receiving timestamp when receiving the first delay measurement message, step S120 is further described. Step S120 includes, but is not limited to, steps S123 to S124.

[0091] Step S123: Obtain the second sending timestamp and the second receiving timestamp;

[0092] Step S124: Based on the second sending timestamp, the second receiving timestamp, the first time information, and the second time information, obtain the cumulative one-way link delay from the source node to the destination node.

[0093] In this step, since the source node stores the second sending timestamp when sending the first delay measurement message and the second receiving timestamp when receiving the first delay measurement message, which means that the overall round-trip time of the measurement message can be reflected in the transmission path, it can be used as the target time information. That is, by combining the delay information of the first time information, the second time information and other subsequent nodes, the cumulative delay of the one-way link from the source node to the destination node can be obtained, which is beneficial to improving the accuracy of delay measurement.

[0094] In one embodiment, the timing of filling in the second sending timestamp and the second receiving timestamp corresponds to the transmission status of the first delay measurement message on the transmission path. For example, when the transmission of the first delay measurement message to the exit of the source node is detected, the second sending timestamp is filled at this time; when the transmission of the first delay measurement message to the entry of the source node is detected, the second receiving timestamp is filled at this time.

[0095] like Figure 9 As shown, in one embodiment of this application, when the first time information includes a third entry timestamp and a third exit timestamp, and the second time information includes a fourth entry timestamp and a fourth exit timestamp, step S124 is further described. Step S124 includes, but is not limited to, step S1241.

[0096] Step S1241: Based on the difference between the second receiving timestamp and the second sending timestamp, the difference between the third exit timestamp and the third entry timestamp, and the difference between the fourth exit timestamp and the fourth entry timestamp, obtain the cumulative one-way link delay from the source node to the destination node.

[0097] In this step, since the difference between the second receiving timestamp and the second sending timestamp represents the overall round-trip time of the measurement message on the transmission path, the difference between the third exit timestamp and the third entry timestamp represents the dwell time of the first delay measurement message at the intermediate node on the transmission path, and the difference between the fourth exit timestamp and the fourth entry timestamp represents the dwell time of the first delay measurement message at the destination node on the transmission path, it can be determined that the other times in the overall round-trip time, excluding the relevant dwell time, are the corresponding one-way cumulative delay of the link from the source node to the destination node on the transmission path, thus the one-way cumulative delay of the link from the source node to the destination node can be accurately obtained.

[0098] In one embodiment, the timing of filling the third exit timestamp and the third entry timestamp, and the timing of filling the fourth exit timestamp and the fourth entry timestamp, correspond to the transmission status of the first delay measurement message on the transmission path. For example, when the first delay measurement message is detected to be transmitted to the entry of the intermediate node, the third entry timestamp is filled at this time; when the first delay measurement message is detected to be transmitted to the exit of the intermediate node, the third exit timestamp is filled at this time; the same applies when the first delay measurement message returns on the transmission path. When the first delay measurement message is detected to be transmitted to the entry of the destination node, the fourth entry timestamp is filled at this time; when the first delay measurement message is detected to be transmitted to the exit of the destination node, the fourth exit timestamp is filled at this time; the same applies when the first delay measurement message returns on the transmission path.

[0099] The following is a specific example to illustrate the working principle and process of the above embodiments.

[0100] Example 4:

[0101] like Figure 10 As shown, Figure 10 A schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application.

[0102] Similar to the implementation principle of Example 1 above, in order to prevent the reduction of the effective payload of the sent message so as to facilitate its application in large-scale networks, this example only records the round-trip cumulative delay of intermediate nodes in the first delay measurement message, and the sending time and receiving time of the first delay measurement message of the source node are maintained locally at the source node.

[0103] Reference Figure 10 Assuming the first delay measurement of the packet in node A is t1 and t2 respectively, the round-trip delay in node B is T1 and T2 respectively, and the delay in node C is T3, then the cumulative delay of the nodes is T = T1 + T2 + T3. Therefore, the cumulative delay of the one-way link is L. 1DM It can be calculated using the following formula:

[0104] L 1DM = (t2-t1-T) / 2;

[0105] Understandably, since the cumulative delay values ​​of the one-way link obtained by sending multiple round-trip measurement messages are equal, the above measurement process only needs to be performed once for a single service path, which can significantly improve measurement efficiency.

[0106] Step S130: Send a second delay measurement message including the one-way link cumulative delay to the destination node, so that the destination node can obtain the one-way delay from the source node to the destination node based on the one-way link cumulative delay.

[0107] In this step, by acquiring the first time information filled by the intermediate node and the second time information filled by the destination node carried in the first delay measurement message traveling between the source node and the destination node, that is, by determining the dwell time of the first delay measurement message at the intermediate node and the destination node, the one-way cumulative delay from the source node to the destination node can be obtained based on the first time information and the second time information. Then, by sending a second delay measurement message including the acquired one-way cumulative delay to the destination node, the one-way delay from the source node to the destination node is determined. Since the acquisition of the one-way cumulative delay or one-way delay involved in the measurement process is carried out within the relevant nodes, that is, it is not necessary to achieve time synchronization between the nodes. Instead, the relevant nodes accurately and reliably obtain the final one-way delay according to the actual delay scenario. Therefore, the embodiments of this application can achieve reliable measurement of one-way delay without time synchronization, improve the measurement accuracy of one-way delay, and thus fill the technical gap in related methods.

[0108] like Figure 11 As shown in the embodiment of this application, step S130 is further described, and step S130 includes, but is not limited to, step S131.

[0109] Step S131: Send a second delay measurement message including the one-way link cumulative delay to the destination node, so that the destination node sends the one-way link cumulative delay to the network controller to obtain the one-way delay from the source node to the destination node.

[0110] In this step, since the network controller can perform real-time management based on the background, that is, the network controller has a high degree of intelligence and has sufficient and complete background operation functions, including calculation and coordination, the one-way link accumulated delay is sent to the network controller so that the network controller can accurately and reliably obtain the one-way delay from the source node to the destination node based on the one-way link accumulated delay. This can eliminate the trouble of calculating the one-way delay through other channels and is conducive to obtaining more accurate delay measurement results.

[0111] In one embodiment, the network controller can be of various types, and is not limited here; since the foregoing embodiments have already described this, it will not be repeated here to avoid redundancy.

[0112] like Figure 12 As shown in the embodiment of this application, step S130 is further described. Step S130 includes, but is not limited to, steps S132 to S134.

[0113] Step S132: Generate a second delay measurement message including the cumulative delay field;

[0114] Step S133: Fill the cumulative delay of the one-way link into the cumulative delay field;

[0115] Step S134: Send a second delay measurement message including a cumulative delay field to the destination node so that the destination node can obtain the one-way delay from the source node to the destination node based on the information in the cumulative delay field. When the second delay measurement message resides on a node in the transmission path, the node will add up the residence time of the second delay measurement message to fill the cumulative delay field.

[0116] In this step, by using the cumulative delay field of the second delay measurement message sent unidirectionally, the dwell time of the second delay measurement message at each node can be continuously added to the cumulative delay field during the transmission of the second delay measurement message to the destination node. Finally, the cumulative delay field is filled with the dwell time of all nodes. At this time, the cumulative delay field can characterize the overall delay of the transmission path. Therefore, the destination node can accurately and reliably calculate the unidirectional delay from the source node to the destination node based on the information in the cumulative delay field.

[0117] In one embodiment, the method of sending a second delay measurement message including a cumulative delay field to the destination node can be varied and is not limited here. For example, it can be, but is not limited to, sending a second delay measurement message including a cumulative delay field to the destination node along the transmission path, wherein intermediate nodes and the destination node are set on the transmission path. That is, by sending a second delay measurement message on the transmission path, the destination node on the transmission path can better obtain the information in the cumulative delay field and obtain the one-way delay from the source node to the destination node based on the information in the cumulative delay field.

[0118] In one embodiment, the cumulative delay field may be, but is not limited to, pre-encapsulated in the second delay measurement message, or may be included in the second delay measurement message by other means. Using the cumulative delay field for measurement calculation will be more convenient, that is, by simply adding the dwell time of the second delay measurement message to the cumulative delay field, there is no need to obtain a new timestamp for calculation, thus greatly improving the efficiency of delay measurement.

[0119] The following is a specific example to illustrate the working principle and process of the above embodiments.

[0120] Example 5:

[0121] Building upon Examples 1 to 4, the end-to-end one-way delay is measured by sending a one-way second delay measurement message, which includes a field 1. DMThis field records the cumulative delay of a one-way link. The initial value of this field is the measured cumulative delay of the one-way link, L1DM. The dwell time of each node is accumulated in this field after passing through each node.

[0122] like Figure 13 As shown, Figure 13 This is a schematic diagram of a time delay measurement method provided in another embodiment of this application, wherein node A is the source node, node B is the intermediate node, and node C is the destination node.

[0123] Reference Figure 13 If the dwell time of the second delay measurement message in node A is T1, in node B is T2, and in node C is T3, then it can be known that when node C receives the second delay measurement message, 1 DM The value of the field is:

[0124] 1 DM =L 1DM +T1+T2+T3;

[0125] Therefore, the one-way end-to-end delay obtained in this measurement process, that is, the one-way delay from source node A to destination node C, is 1. DM .

[0126] One-way delay measurement can be performed multiple times, and the measurement frequency can be determined according to actual needs. For example, the source node can send multiple one-way second delay measurement messages according to the planned measurement frequency, but is not limited to this. The processing process of each second delay measurement message is as shown in Example 5. It is clear that due to the jitter of node processing delay, the results of each one-way delay measurement are not necessarily the same. This can reflect the real-time changes in node processing time and is within an acceptable range.

[0127] Compared to related technologies, the embodiments of this application do not require correlating the theoretical and actual values ​​of the one-way transmission delay of the reference message, but directly measuring it. Even if the reference message has jitter or other reasons, it will not affect the normal execution of the embodiments of this application, and has higher measurement stability. Furthermore, the embodiments of this application do not require assuming other delays besides the queuing delay as constant values, and then applying algorithms such as differential fitting to estimate the queuing delay, which can greatly reduce measurement errors.

[0128] Example 6:

[0129] like Figure 14 As shown, Figure 14 A schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application.

[0130] Reference Figure 14Node A is the source node, node B is intermediate node 1, node C is intermediate node 2, and node D is the destination node.

[0131] If the one-way link delay has been measured to be 4, then the one-way delay field 1 will be... DM The initial value is set to 4. The dwell time of the second delay measurement message at each node is as follows: 2 in node A, 2 in node B, 1 in node C, and 2 in node D. Therefore, in node D, the one-way delay field 1 of the second delay measurement message... DM The value is:

[0132] 1 DM =4+2+2+1+2=11.

[0133] Example 7:

[0134] like Figure 15 As shown, Figure 15 A schematic diagram illustrating the principle of a time delay measurement method provided in another embodiment of this application.

[0135] Reference Figure 15 Node A is the source node, node B is intermediate node 1, node C is intermediate node 2, and node D is the destination node.

[0136] If the one-way link delay has been measured to be 4, then the one-way delay field 1 will be... DM The initial value is set to 4. The dwell time of the second delay measurement message at each node is as follows: 2 in node A, 3 in node B, 2 in node C, and 1 in node D. Therefore, in node D, the one-way delay field 1 of the second delay measurement message... DM The value is:

[0137] 1 DM =4+2+3+2+1=12;

[0138] As can be seen from Example 6, the one-way delay obtained in each measurement is different, which can accurately reflect the changes in node processing delay.

[0139] In one embodiment, both the first delay measurement message and the second delay measurement message can be, but are not limited to, Operation Administration and Maintenance (OAM) protocol measurement messages. The OAM protocol measurement message includes a measurement type flag field. When the measurement type flag field is set to a first preset value, the OAM protocol measurement message is configured as a first delay measurement message; when the measurement type flag field is set to a second preset value, the OAM protocol measurement message is configured as a second delay measurement message. That is, the sending of either a first delay measurement message or a second delay measurement message can be determined based on the measurement type flag field. Since the measurement functions of the first delay measurement message and the second delay measurement message are different, in practical applications, the specific message to be sent can be selected according to the specific scenario. This improves the convenience and reliability of the measurement operation and helps optimize the overall measurement process of this application embodiment.

[0140] In one embodiment, the OAM protocol measurement message further includes an ingress timestamp field and an egress timestamp field. The ingress timestamp field is used to fill in the timestamp when the OAM protocol measurement message is received, and the egress timestamp field is used to fill in the timestamp when the OAM protocol measurement message is sent. By setting the ingress and egress timestamp fields, the timestamps when the OAM protocol measurement message is received and when it is sent can be filled in respectively, ensuring that timestamps can be stably and reliably applied in the corresponding scenarios.

[0141] In one embodiment, the OAM protocol measurement message also includes a dwell time field, which is used to fill in the dwell time of the OAM protocol measurement message in the node. By setting the dwell time field, the dwell time of the OAM protocol measurement message in the node can be filled in, ensuring that the dwell time can be accumulated stably and reliably when passing through each node. Finally, a cumulative delay field filled with the dwell time of all nodes is obtained, which allows the destination node to accurately and reliably calculate the one-way delay from the source node to the destination node based on the information in the cumulative delay field.

[0142] In one embodiment, there are no restrictions on the OAM protocol carrier used and the specific encapsulation format of the above-mentioned fields in the OAM protocol measurement message. For example, novel flow detection technologies such as alternating marking and in-situ OAM can process messages in the middle, so such OAM protocols can be extended as the carrier of the measurement process in the embodiments of this application. However, it is not excluded that other OAM protocols can be used as the carrier of the measurement message used in the embodiments of this application. For example, for alternating marking technology, the measurement message type can be marked with 1 bit in the message, and each node reports the processing delay of the forward and reverse nodes to the network controller. The network controller calculates the one-way link cumulative delay and one-way delay according to the corresponding formula in the above example. For example, the Trace Option-type header of in-situ OAM can be easily extended to mark the measurement message type and record the outgoing and incoming timestamps of the message of each node. That is to say, the choice of which OAM technology to use depends on the actual needs of those skilled in the art. Here, there are no restrictions on the specific utilization of the above OAM protocol, the specific definition of the protocol fields, etc., and they will not be described in detail.

[0143] The following is a specific example to illustrate the working principle and process of the above embodiments.

[0144] Example 8:

[0145] like Figure 16 As shown, Figure 16 This is a schematic diagram showing the encapsulation of fields required for a delay measurement method provided in one embodiment of this application in an OAM protocol measurement message.

[0146] Taking the in-situ OAM protocol as an example, the existing encapsulation of in-situ OAM has defined a loopback flag field to indicate the remote message loopback operation. Therefore, when this field is set, it can indicate the first delay measurement message, and when this field is set to zero, it can indicate the second delay measurement message.

[0147] Reference Figure 16 (a) The In-situ OAM encapsulation draft has defined the Trace Option-type header to support recording information of each node in a specified format. This example uses this encapsulation header to record the in and out timestamp information of each node.

[0148] Reference Figure 16 (b) The In-situ OAM draft defines the Proof-of-Transit Option-type, whose header carries fields that can be modified at each intermediate node. This example uses this encapsulation header to carry the round-trip cumulative delay field and the one-way cumulative delay field.

[0149] In the Trace Option-type header, IOAM-Trace-Type indicates the position, length, and format of the fields inserted into the measurement message at each node. IOAM-Trace-Type consists of 24 bits; each bit set to 1 indicates that a value is inserted into the node information. For example:

[0150] Bit 0 indicates that the measurement message carries a shorthand for hop_limit and node ID;

[0151] The first bit indicates that the ingress_if_id and egress_if_id are carried in the measurement message;

[0152] The second bit represents the seconds portion of the timestamp carried in the measurement message, and so on...

[0153] Currently, bits 0-11 and 22 have been defined, bits 12-21 are not yet defined, and bit 23 must be set to 0. Therefore, bits 12-21 can be defined to carry the required information. All information must be a multiple of 4 bytes, for example:

[0154] The 12th bit is defined to represent the node entry timestamp carried in the measurement message, which occupies 4 bytes;

[0155] The 13th bit is defined as representing the node's egress timestamp carried in the measurement message, which occupies 4 bytes.

[0156] Assuming bits 0-11 and 14-22 of IOAM-Trace-Type are all set to 0, and bits 12-13 are set, then the encapsulation format of the IOAM message at each node is as follows: Figure 16 As shown in (c).

[0157] In the Proof-of-Transit Option-type header, IOAM-PoT-Type indicates the information carried in the header, including the order, length, and meaning of fields. IOAM-PoT-Type has 8 bits. Currently, IOAM-PoT-Type = 0 is defined, and the remaining values ​​are undefined. This example can define the following:

[0158] like Figure 16 As shown in (d), IOAM-PoT-Type=1 indicates that the Pot-option-data field carries round-trip node accumulative delay information, which occupies 4 bytes;

[0159] like Figure 16 As shown in (e), IOAM-PoT-Type=2 indicates that the Pot-option-data field carries the one-way delay field information, which occupies 4 bytes.

[0160] In addition, such as Figure 17 As shown, one embodiment of this application also discloses a time delay measurement device 100, including: at least one processor 110; at least one memory 120 for storing at least one program; when the at least one program is executed by the at least one processor 110, it implements the time delay measurement method as in any of the preceding embodiments.

[0161] In addition, one embodiment of this application discloses a computer-readable storage medium storing computer-executable instructions for performing the delay measurement method as described in any of the preceding embodiments.

[0162] Furthermore, one embodiment of this application also discloses a computer program product, including a computer program or computer instructions, which are stored in a computer-readable storage medium. A processor of a computer device reads the computer program or computer instructions from the computer-readable storage medium and executes the computer program or computer instructions, causing the computer device to perform the delay measurement method as described in any of the preceding embodiments.

[0163] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

Claims

1. A time delay measurement method, comprising: Obtain the target time information carried in the first delay measurement message, wherein the target time information includes first time information filled by intermediate nodes on the transmission path and second time information filled by the destination node, the first time information is used to obtain the dwell time of the first delay measurement message at the intermediate node, and the second time information is used to obtain the dwell time of the first delay measurement message at the destination node. The cumulative one-way link delay from the source node to the destination node is obtained based on the first time information and the second time information. A second delay measurement message including the one-way link accumulated delay is sent to the destination node so that the destination node can obtain the one-way delay from the source node to the destination node based on the one-way link accumulated delay; The step of sending a second delay measurement message including the one-way link accumulated delay to the destination node, so that the destination node can obtain the one-way delay from the source node to the destination node based on the one-way link accumulated delay, includes: Generate a second delay measurement message that includes a cumulative delay field; Fill the cumulative delay of the unidirectional link into the cumulative delay field; A second delay measurement message including the cumulative delay field is sent to the destination node so that the destination node can obtain the one-way delay from the source node to the destination node based on the information in the cumulative delay field. When the second delay measurement message resides at a node on the transmission path, the node accumulates the residence time of the second delay measurement message and fills it into the cumulative delay field.

2. The time delay measurement method according to claim 1, characterized in that, The step of obtaining the target time information carried in the first delay measurement message includes: Send the first delay measurement message, including a loopback marker, to the destination node; When the destination node receives the first delay measurement message returned by the loopback marker, wherein the first delay measurement message resides in the intermediate node and the destination node on the transmission path, the intermediate node fills the first delay measurement message with the first time information, and the destination node fills the first delay measurement message with the second time information; The target time information, including the first time information and the second time information, is obtained from the first delay measurement message.

3. The time delay measurement method according to claim 2, characterized in that, The target time information also includes the first sending timestamp and the first receiving timestamp filled by the source node; The step of obtaining the target time information, including the first time information and the second time information, from the first delay measurement message includes: The target time information, including the first time information, the second time information, the first sending timestamp, and the first receiving timestamp, is obtained from the first delay measurement message.

4. The time delay measurement method according to claim 3, characterized in that, The step of obtaining the cumulative one-way link delay from the source node to the destination node based on the first time information and the second time information includes: Based on the first time information, the second time information, the first sending timestamp, and the first receiving timestamp, the cumulative one-way link delay from the source node to the destination node is obtained.

5. The time delay measurement method according to claim 4, characterized in that, The first time information includes a first entry timestamp and a first exit timestamp, and the second time information includes a second entry timestamp and a second exit timestamp; The step of obtaining the cumulative one-way link delay from the source node to the destination node based on the first time information, the second time information, the first sending timestamp, and the first receiving timestamp includes: The cumulative one-way link delay from the source node to the destination node is calculated based on the difference between the first exit timestamp and the first entry timestamp, the difference between the second exit timestamp and the second entry timestamp, and the difference between the first receive timestamp and the first send timestamp.

6. The time delay measurement method according to claim 1, characterized in that, The source node stores a second sending timestamp when sending the first delay measurement message and a second receiving timestamp when receiving the first delay measurement message; The step of obtaining the cumulative one-way link delay from the source node to the destination node based on the first time information and the second time information includes: Obtain the second sending timestamp and the second receiving timestamp; The cumulative one-way link delay from the source node to the destination node is obtained based on the second sending timestamp, the second receiving timestamp, the first time information, and the second time information.

7. The time delay measurement method according to claim 6, characterized in that, The first time information includes a third entry timestamp and a third exit timestamp, and the second time information includes a fourth entry timestamp and a fourth exit timestamp; The step of obtaining the cumulative one-way link delay from the source node to the destination node based on the second sending timestamp, the second receiving timestamp, the first time information, and the second time information includes: The cumulative one-way link delay from the source node to the destination node is calculated based on the difference between the second receiving timestamp and the second sending timestamp, the difference between the third exit timestamp and the third entry timestamp, and the difference between the fourth exit timestamp and the fourth entry timestamp.

8. The time delay measurement method according to claim 1, characterized in that, Both the first latency measurement message and the second latency measurement message are operation and maintenance management protocol measurement messages. The operation and maintenance management protocol measurement message includes a measurement type flag field. When the value of the measurement type flag field is a first preset value, the operation and maintenance management protocol measurement message is configured as the first latency measurement message; when the value of the measurement type flag field is a second preset value, the operation and maintenance management protocol measurement message is configured as the second latency measurement message.

9. The time delay measurement method according to claim 8, characterized in that, The operation and maintenance management protocol measurement message also includes an ingress timestamp field and an egress timestamp field. The ingress timestamp field is used to fill in the timestamp when the operation and maintenance management protocol measurement message is received, and the egress timestamp field is used to fill in the timestamp when the operation and maintenance management protocol measurement message is sent.

10. The time delay measurement method according to claim 8, characterized in that, The operation and maintenance management protocol measurement message also includes a residence time field, which is used to fill in the residence time of the operation and maintenance management protocol measurement message in the node.

11. The time delay measurement method according to claim 1, characterized in that, The step of obtaining the cumulative one-way link delay from the source node to the destination node based on the first time information and the second time information includes: The first time information and the second time information are sent to the network controller so that the network controller can obtain the cumulative one-way link delay from the source node to the destination node based on the first time information and the second time information.

12. The time delay measurement method according to claim 1, characterized in that, Sending a second delay measurement message, including the one-way link accumulated delay, to the destination node so that the destination node can obtain the one-way delay from the source node to the destination node based on the one-way link accumulated delay includes: A second delay measurement message including the one-way link accumulated delay is sent to the destination node, causing the destination node to send the one-way link accumulated delay to the network controller to obtain the one-way delay from the source node to the destination node.

13. A time delay measurement device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the computer program, implements the time delay measurement method as described in any one of claims 1 to 12.

14. A computer-readable storage medium storing computer-executable instructions for performing the time delay measurement method according to any one of claims 1 to 12.

15. A computer program product, comprising a computer program or computer instructions, characterized in that, The computer program or the computer instructions are stored in a computer-readable storage medium, and the processor of the computer device reads the computer program or the computer instructions from the computer-readable storage medium. The processor executes the computer program or the computer instructions, causing the computer device to perform the delay measurement method as described in any one of claims 1 to 12.

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