Optical link anomaly detection method, device and storage medium

Abstract

The embodiment of the present invention provides an optical link anomaly detection method, comprising the following steps: obtaining the first optical link fault information of the downlink port of the opposite device; obtaining the second optical link fault information of the port of the local device connected to the downlink port of the opposite device; determining the cause of the optical link fault according to the first optical link fault information and the second optical link fault information according to a predefined rule. At the same time, the embodiment of the present invention also provides an optical link anomaly detection device. The embodiment of the present invention allows the operation and maintenance personnel to obtain the optical link fault information between the local device and the opposite device in the most convenient and fast way. The solution reduces the operation and maintenance costs and the requirements for the technical capabilities of the operation and maintenance personnel, and improves work efficiency.

Description

Technical Field

[0001] The present invention relates to the field of data communication, and in particular to an optical link anomaly detection method, device and storage medium. Background Art

[0002] With the rapid development of communication technology, people have an increasingly strong demand for high bandwidth, which further promotes the evolution trend of "optical fiber replacing copper fiber". Fiber-to-the-home solves the communication layout design of the last mile and realizes the high-bandwidth experience of users. At the same time, due to the particularity of optical signals, the detection mechanism of optical anomalies has become increasingly important.

[0003] Specifically, most of the current access switches use optical links for uplink; the benefits of optical links for uplink include: increased bandwidth, and the uplink basically maintains the gigabit bandwidth level. With the popularization of VR / HD video / wifi6, gigabit uplinks are obviously insufficient in bandwidth. Optical links are based on 10 Gigabit and can meet bandwidth requirements; when cables are used for uplink, rewiring is required for bandwidth upgrades, while when optical links are used for uplink, bandwidth upgrades to 25G / 100G, etc. only require equipment replacement, greatly reducing construction costs; cables take up a lot of space, and optical uplinks effectively solve this problem.

[0004] Compared with traditional network deployment, the existing solution has released the active access switch from the weak current room on the floor, and deployed the all-optical access switch in each room through fiber-to-the-home. The all-optical access switch in the room and the core full link use the optical fiber channel. However, the number of optical links has increased, so the operation and maintenance of optical links is the key requirement of this solution.

[0005] In the actual topology, the distance of the optical link is very long, and the longest optical link can reach 100 kilometers, which brings a lot of difficulties to the analysis of optical link faults. Unlike network cables, the optical signal anomaly troubleshooting mechanism is relatively complex, including optical signal reception anomalies, transmission anomalies, module anomalies, etc., which brings a lot of challenges to operation and maintenance / repair. During deployment and operation and maintenance, if anomalies occur, the existing practices are based on the long-term experience accumulation of operation and maintenance personnel, and use external tools to check the anomalies one by one, which takes a long time; most switches can remind operation and maintenance personnel of the current module anomalies through logs, but this function is limited to identifying reception / transmission problems, and cannot further locate the specific link / device anomalies.

[0006] Therefore, a method that can conveniently detect light anomalies becomes particularly important. Summary of the invention

[0007] In order to solve the above technical problems, the embodiments of the present invention adopt the following technical solutions:

[0008] An optical link anomaly detection method, comprising:

[0009] Obtaining first optical link fault information of a downlink port of a peer device;

[0010] Acquire second optical link fault information of a port of the local device connected to the downlink port of the opposite device; determine the cause of the optical link fault according to the first optical link fault information and the second optical link fault information in accordance with a predefined rule.

[0011] Optional,

[0012] The step of obtaining the first optical link fault information of the downlink port of the opposite end device comprises:

[0013] Sending the local device identifier to a server, so that the server can determine the opposite device corresponding to the local device identifier according to predetermined network topology information, and send a request to the opposite device to obtain the first optical link fault information of the downlink port of the opposite device;

[0014] The first optical link failure information of the downlink port of the opposite device is obtained from the server.

[0015] Optional,

[0016] The step of sending the local device identifier to the server so that the server determines the opposite device corresponding to the local device identifier according to predetermined network topology information, and sending a request for obtaining the first optical link fault information of the downlink port of the opposite device to the opposite device comprises:

[0017] After scanning the QR code on the local device, the local device identification is obtained and sent to the server according to the information in the QR code, so that the server can determine the opposite device corresponding to the local device identification according to the predetermined network topology information, and send a request to the opposite device to obtain the first optical link fault information of the lower port of the opposite device.

[0018] Optional,

[0019] The step of obtaining the second optical link fault information of the port of the local device connected to the downlink port of the opposite device comprises:

[0020] Scan the QR code on the local device and select the second optical link fault information of the port of the local device connected to the downlink port of the opposite device according to the displayed drop-down box.

[0021] Optional,

[0022] The first optical link fault information is first indicator light status information corresponding to the optical link fault;

[0023] The second optical link fault information is second indicator light status information corresponding to the optical link fault;

[0024] The predefined rule is the fault cause corresponding to the first indicator light status information and the second indicator light status information.

[0025] Another aspect of an embodiment of the present invention is to provide an optical link abnormality detection device, including:

[0026] A first acquisition module, used to acquire first optical link fault information of a downlink port of an opposite end device;

[0027] A second acquisition module, used to acquire second optical link fault information of a port of the local device connected to the downlink port of the opposite device;

[0028] The determination module is used to determine the cause of the optical link failure according to the first optical link failure information and the second optical link failure information according to a predefined rule.

[0029] Optional,

[0030] The first acquisition module specifically includes:

[0031] a sending unit, configured to send the local device identifier to a server, so that the server determines the opposite device corresponding to the local device identifier according to predetermined network topology information, and sends a request to the opposite device to obtain the first optical link fault information of the downlink port of the opposite device,

[0032] The acquisition unit is used to acquire the first optical link fault information of the downlink port of the opposite end device from the server.

[0033] Optional,

[0034] The sending unit is specifically used for:

[0035] After scanning the QR code on the local device, the local device identification is obtained and sent to the server according to the information in the QR code, so that the server can determine the opposite device corresponding to the local device identification according to the predetermined network topology information, and send a request to the opposite device to obtain the first optical link fault information of the lower port of the opposite device.

[0036] Optional,

[0037] The second acquisition module is specifically used for:

[0038] Scan the QR code on the local device and select the second optical link fault information of the port of the local device connected to the downlink port of the opposite device according to the displayed drop-down box.

[0039] Optional,

[0040] The first optical link fault information is first indicator light status information corresponding to the optical link fault;

[0041] The second optical link fault information is second indicator light status information corresponding to the optical link fault;

[0042] The predefined rule is the fault cause corresponding to the first indicator light status information and the second indicator light status information.

[0043] Another aspect of an embodiment of the present invention is to provide a computer device, including:

[0044] A memory for storing program instructions;

[0045] The processor is used to call the program instructions stored in the memory and execute the method as described in the first aspect according to the obtained program instructions.

[0046] Another aspect of the embodiments of the present invention is to provide a computer-readable storage medium, wherein the storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the method as described in the first aspect.

[0047] The beneficial effects of the embodiments of the present invention are as follows: by obtaining the first optical link fault information of the downlink port of the opposite device; obtaining the second optical link fault information of the port of the local device connected to the downlink port of the opposite device; determining the cause of the optical link failure according to the first optical link fault information and the second optical link fault information according to predefined rules, the operation and maintenance personnel can obtain the optical link fault information between the local device and the opposite device (such as the local access switch and the opposite aggregation switch) in the most convenient and fastest way. This solution reduces the operation and maintenance costs and the requirements for the technical capabilities of the operation and maintenance personnel, and improves work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0049] Figure 1 A method flow chart provided for an embodiment of the present invention;

[0050] Figure 2 A structural diagram of a device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] An optical link anomaly detection method, such as Figure 1 As shown, including:

[0053] S101, obtaining first optical link fault information of a downlink port of a peer device;

[0054] S103, obtaining second optical link fault information of a port of the local device connected to the downlink port of the opposite device;

[0055] S105: Determine a cause of the optical link failure according to the first optical link failure information and the second optical link failure information according to a predefined rule.

[0056] Optional,

[0057] The step of obtaining the first optical link fault information of the downlink port of the opposite end device comprises:

[0058] Sending the local device identifier to a server, so that the server can determine the opposite device corresponding to the local device identifier according to predetermined network topology information, and send a request to the opposite device to obtain the first optical link fault information of the downlink port of the opposite device;

[0059] The first optical link failure information of the downlink port of the opposite device is obtained from the server.

[0060] Optional,

[0061] The step of sending the local device identifier to the server so that the server determines the opposite device corresponding to the local device identifier according to predetermined network topology information, and sending a request for obtaining the first optical link fault information of the downlink port of the opposite device to the opposite device comprises:

[0062] After scanning the QR code on the local device, the local device identification is obtained and sent to the server according to the information in the QR code, so that the server can determine the opposite device corresponding to the local device identification according to the predetermined network topology information, and send a request to the opposite device to obtain the first optical link fault information of the lower port of the opposite device.

[0063] Optional,

[0064] The step of obtaining the second optical link fault information of the port of the local device connected to the downlink port of the opposite device comprises:

[0065] Scan the QR code on the local device and select the second optical link fault information of the port of the local device connected to the downlink port of the opposite device according to the displayed drop-down box.

[0066] Optional,

[0067] The first optical link fault information is first indicator light status information corresponding to the optical link fault;

[0068] The second optical link fault information is second indicator light status information corresponding to the optical link fault;

[0069] The predefined rule is the fault cause corresponding to the first indicator light status information and the second indicator light status information.

[0070] In one embodiment of the present invention, the local device may be an access switch, and the opposite device may be an aggregation switch. In order to collect optical module fault information, the overall framework in each device may include three main modules: a main chip (MAC chip), an optical module, and an LED.

[0071] The main functions of the main chip include: 1. Identify whether an optical module is inserted; 2. Identify the type of optical module; 3. Control the light emission of the optical module; 4. Identify the abnormal TX / RX transmission of the optical module; 5. Data exchange between links; 6. Path abnormality lighting alarm mechanism;

[0072] Function of optical module: Photoelectric conversion, thereby realizing data interaction between access and aggregation switches;

[0073] LED function: under the control of the main chip, the lights of different colors can be turned on / flashed / off to intuitively inform users of link failure anomalies;

[0074] Based on the above three major modules, the process of collecting fault information in each switch is as follows:

[0075] 1. The operation process of each pin on the main chip is as follows:

[0076] Present is an input signal (an interrupt signal). This pin is connected to the in-position pin of the optical module. The pin is pulled high externally. When an optical module is inserted into the board, the pin level is pulled low, so that the main chip determines that a module is inserted at this time (an interrupt signal);

[0077] Tx-dis is the output signal, which is externally pulled up to a high level to control the on and off of the laser of the optical module. When working normally, Tx-dis is set to a low level and the optical module emits light. When the laser needs to be turned off, tx-dis is set to a high level.

[0078] Rx_los is an input signal (an interrupt signal), which is externally pulled up to a high level. When the optical module receives an abnormal signal, Rx_los is set high, and the main chip receives the abnormal information. The main chip lights up the yellow light of the optical operation and maintenance LED according to the abnormality reported by Rx_los.

[0079] Tx-fault is an input signal (an interrupt signal), which is pulled high externally. When the transmitting end of the optical module is abnormal, Tx_fault will be pulled high. The main chip obtains the abnormality of the transmitting end of the optical module. The main chip lights up the red light of the optical operation and maintenance LED according to the Tx_fault abnormal information (and when Rx_los and Tx_fault are abnormal at the same time, the red light flashes).

[0080] 2. Optical module

[0081] The optical module mainly realizes photoelectric conversion and realizes data interaction between the device and the docking device. The I2C bus of the optical module is connected to the main chip through a switch, and the in-position pin is directly connected to the main chip. The I2C bus is mainly used for the main chip to access the optical module, and the in-position signal is used to indicate whether an optical module is inserted into the board.

[0082] It should be noted that the main fault phenomena of optical fiber lines are core breakage and excessive loss; optical module failures are mainly divided into transmitter and receiver failures, among which the transmitter is mainly manifested in poor bias current, while the receiver failure is mainly reflected in the loss of received signals, and other abnormalities are mainly reflected in poor DDM (digital diagnostic monitoring). Users may not care about the specific details of optical module and optical fiber failures, such as where the optical module is faulty or where the optical fiber line is broken, but they want to know whether the optical fiber line or the optical module needs to be replaced. Therefore, the main problems solved by this solution are as follows:

[0083] The quick location of an optical link fault is to determine which optical module on the local or remote end is faulty.

[0084] Optical link fault: Quickly locate whether the optical fiber is faulty.

[0085] The fault information of the optical link is mainly parsed from the DDM information inside the optical module, which contains five information parameters, as shown in Table 1:

[0086] DDM parameters meaning temperature Optical module housing temperature Voltage Port supply voltage Bias Current Transmitting current of the optical module Transmit optical power Optical power transmitted by the optical module Received optical power Optical power received by the optical module

[0087] Table 1

[0088] The main factors that affect Link up are bias current and received optical power RX_POWER alarms. For DDM information escape, rules are defined. By default, red is considered the highest level of fault information, followed by yellow. The rules are defined as shown in Table 2 below:

[0089]

[0090] Table 2

[0091] In one embodiment of the present invention, the server may save in advance a network topology diagram including access switches and aggregation switches. The diagram may include a port connection relationship between the access switches and the aggregation switches.

[0092] After the user uses a mobile terminal to scan the QR code on the local access switch, the local device identifier is obtained and sent to the server according to the information in the QR code, so that the server determines the opposite device corresponding to the local device identifier according to the predetermined network topology information, and sends a request to the opposite device to obtain the first optical link fault information of the downlink port of the opposite device;

[0093] The first optical link fault information of the downlink port of the opposite aggregation switch is obtained from the server.

[0094] After obtaining the first optical link fault information, the user can use the mobile terminal to scan the QR code on the local access switch and select the second optical link fault information of the port of the local access switch connected to the downlink port of the opposite aggregation switch according to the displayed drop-down box.

[0095] By scanning, the optical link information of the uplink port of the access switch fault link connected to the downlink port of the opposite-end aggregation switch can be parsed, and it is escaped. Combined with the lighting status of the local access switch, the mobile terminal provides a lighting drop-down box to select the lighting status, and finally determines whether it is an optical module problem or an optical fiber problem. The specific judgment process is shown in Table 3 below, where the optical module is divided into two types in this embodiment: bidi optical module and dual-fiber optical module. Bidi optical module refers to a single optical fiber and bidirectional transmission (that is, the input and output are the same port, and an optical fiber is connected externally), while dual-fiber optical module refers to two optical fibers and bidirectional transmission (that is, the input and output are separated and two optical fibers are connected externally). In this way, the cause of the fault can also be divided into the cause of the fault for the bidi optical module and the cause of the fault for the dual-fiber optical module. If the type of the optical module is a bidi optical module or a dual-fiber optical module is not marked in the cause of the fault (in the brackets after the cause of the fault), then the cause of the fault exists in both optical modules. At the same time, both optical modules have an A end (this end) and a B end (the opposite end).

[0096] In another embodiment of the present invention, the fault causes and suggestions jointly determined by the indicator light states of the A end and the B end are shown in Table 3, where RX represents receiving and TX represents sending.

[0097]

[0098]

[0099] Table 3

[0100] In Table 3, a cell may correspond to a fault cause and troubleshooting suggestion jointly determined by the status of the indicator lights at the A end and the B end. For example, if the indicator light at the A end is off and the indicator light at the B end is always yellow, the fault cause may be: the optical module is not inserted; suggestion: confirm whether the module at the A end is inserted normally; in addition, some cells correspond to normal status, for example, if the indicator light at the A end is always green and the indicator light at the B end is also always green, then the corresponding status in the corresponding cell is normal and there is no fault. Finally, some cells correspond to non-existent status, that is, in this case, the indicator light status at the A end and the indicator light status at the B end cannot appear at the same time in practice, and this status does not exist. By analogy, other status confirmation results are shown in Table 3, which are not described one by one here.

[0101] The beneficial effects of the embodiments of the present invention are as follows: by obtaining the first optical link fault information of the downlink port of the opposite device; obtaining the second optical link fault information of the port of the local device connected to the downlink port of the opposite device; determining the cause of the optical link failure according to the first optical link fault information and the second optical link fault information according to predefined rules, the operation and maintenance personnel can obtain the optical link fault information between the local device and the opposite device (such as the local access switch and the opposite aggregation switch) in the most convenient and fastest way. This solution reduces the operation and maintenance costs and the requirements for the technical capabilities of the operation and maintenance personnel, and improves work efficiency.

[0102] Another aspect of the present invention is to provide an optical link abnormality detection device, such as Figure 2 As shown, including:

[0103] A first acquisition module 201 is used to acquire first optical link fault information of a downlink port of an opposite device;

[0104] The second acquisition module 203 is used to obtain the second optical link fault information of the port of the local device connected to the downlink port of the opposite device;

[0105] The determination module 205 is configured to determine the cause of the optical link failure according to the first optical link failure information and the second optical link failure information according to a predefined rule.

[0106] The first acquisition module specifically includes:

[0107] a sending unit, configured to send the local device identifier to a server, so that the server determines the opposite device corresponding to the local device identifier according to predetermined network topology information, and sends a request to the opposite device to obtain the first optical link fault information of the downlink port of the opposite device,

[0108] The acquisition unit is used to acquire the first optical link fault information of the downlink port of the opposite end device from the server.

[0109] Optional,

[0110] The sending unit is specifically used for:

[0111] After scanning the QR code on the local device, the local device identification is obtained and sent to the server according to the information in the QR code, so that the server can determine the opposite device corresponding to the local device identification according to the predetermined network topology information, and send a request to the opposite device to obtain the first optical link fault information of the lower port of the opposite device.

[0112] Optional,

[0113] The second acquisition module is specifically used for:

[0114] Scan the QR code on the local device and select the second optical link fault information of the port of the local device connected to the downlink port of the opposite device according to the displayed drop-down box.

[0115] Optional,

[0116] The first optical link fault information is first indicator light status information corresponding to the optical link fault;

[0117] The second optical link fault information is second indicator light status information corresponding to the optical link fault;

[0118] The predefined rule is the fault cause corresponding to the first indicator light status information and the second indicator light status information.

[0119] Another aspect of an embodiment of the present invention is to provide a computer device, including:

[0120] A memory for storing program instructions;

[0121] The processor is used to call the program instructions stored in the memory, and execute the optical link anomaly detection method provided in the above embodiment according to the obtained program instructions.

[0122] Another aspect of the embodiments of the present invention is to provide a computer-readable storage medium, wherein the storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the optical link anomaly detection method provided in the above embodiments.

[0123] The beneficial effects of the embodiments of the present invention are as follows: by obtaining the first optical link fault information of the downlink port of the opposite device; obtaining the second optical link fault information of the port of the local device connected to the downlink port of the opposite device; determining the cause of the optical link failure according to the first optical link fault information and the second optical link fault information according to predefined rules, the operation and maintenance personnel can obtain the optical link fault information between the local device and the opposite device (such as the local access switch and the opposite aggregation switch) in the most convenient and fastest way. This solution reduces the operation and maintenance costs and the requirements for the technical capabilities of the operation and maintenance personnel, and improves work efficiency.

[0124] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0125] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0126] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process in the computer or other programmable device. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0127] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for detecting anomalies in an optical link, characterized in that: include: Sending a local device identifier to a server, wherein the local device identifier is used by the server to send a request to obtain first optical link fault information of a downlink port of the opposite device to the opposite device after the server determines the opposite device corresponding to the local device identifier; Acquire first optical link fault information of the downlink port of the opposite device from the server; Obtaining second optical link fault information of a port of the local device connected to the downlink port of the opposite device; The cause of the optical link failure is determined according to the first optical link failure information and the second optical link failure information according to a predefined rule.

2. The method according to claim 1, characterized in that The sending the local device identifier to the server includes: The local device identification is obtained and sent to the server according to the information in the QR code on the local device; the local device identification is used by the server to send a request to obtain the first optical link fault information of the downlink port of the opposite device after determining the opposite device corresponding to the local device identification according to predetermined network topology information.

3. The method according to claim 1, characterized in that The step of obtaining the second optical link fault information of the port of the local device connected to the downlink port of the opposite device comprises: Scan the QR code on the local device and select the second optical link fault information of the port of the local device connected to the downlink port of the opposite device according to the displayed drop-down box.

4. The method according to claim 1, characterized in that The first optical link fault information is first indicator light status information corresponding to the optical link fault; The second optical link fault information is second indicator light status information corresponding to the optical link fault; The predefined rule is the fault cause corresponding to the first indicator light status information and the second indicator light status information.

5. An optical link anomaly detection device, characterized in that: include: A first acquisition module, configured to send the local device identifier to a server, wherein the local device identifier is used by the server to send a request for acquiring first optical link fault information of a downlink port of the opposite device to the opposite device after the server determines the opposite device corresponding to the local device identifier; The first acquisition module is further used to obtain the first optical link fault information of the downlink port of the opposite device from the server; A second acquisition module, used to acquire second optical link fault information of a port of the local device connected to the downlink port of the opposite device; The determination module is used to determine the cause of the optical link failure according to the first optical link failure information and the second optical link failure information according to a predefined rule.

6. The device according to claim 5, characterized in that The first acquisition module is specifically used for: The local device identifier is obtained and sent to the server based on the information in the QR code on the local device; the local device identifier is used by the server to send a request to obtain the first optical link fault information of the downlink port of the opposite device after determining the opposite device corresponding to the local device identifier based on predetermined network topology information.

7. The device according to claim 5, characterized in that The second acquisition module is specifically used for: Scan the QR code on the local device and select the second optical link fault information of the port of the local device connected to the downlink port of the opposite device according to the displayed drop-down box.

8. The device according to claim 5, characterized in that The first optical link fault information is first indicator light status information corresponding to the optical link fault; The second optical link fault information is second indicator light status information corresponding to the optical link fault; The predefined rule is the fault cause corresponding to the first indicator light status information and the second indicator light status information.

9. A computer device, characterized in that: include: A memory for storing program instructions; The processor is used to call the program instructions stored in the memory, and execute the method according to any one of claims 1 to 4 according to the obtained program instructions.

10. A computer-readable storage medium, characterized in that: The storage medium stores computer-executable instructions, and the computer-executable instructions are used to enable a computer to execute the method according to any one of claims 1 to 4.

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