CN114531414A - Terminal migration acceleration method and device - Google Patents

Abstract

The present invention discloses a method and device for accelerating terminal migration. The method is applied to switching equipment, comprising: when the terminal accesses the switching equipment for the first time, the media access control MAC authentication is passed; The Internet Protocol address IP and the media access control address MAC are stored in the chip as global user entries; and the MAC authentication module of the switching device sends an address resolution protocol ARP detection message to the terminal to perform the ARP entry. study. The embodiments of the present invention can solve the problem in the prior art that the terminal migration time is too long, resulting in an excessively long disconnection time.

Description

Method and device for accelerating terminal migration

technical field

The present invention relates to the field of data communication, in particular to a method and device for accelerating terminal migration.

Background technique

Media Access Control (MAC) address authentication is used in terminal access scenarios. Only the terminal can access the network after passing the MAC address authentication. After the authentication is passed, the Internet Protocol (IP) including the terminal is set. The user entries of the address, MAC, and PORT information of the access port are stored in the hardware chip of the switching device. Only the end users that meet the information of these user entries are allowed to access the network, and the user's traffic can be released in the switching device. Traffic is blocked.

After the terminal's MAC authentication is passed, the interface of the switching device accessed by the terminal may change or re-connect to the new switching device. Such changes in the interface of the terminal accessing the switching device or accessing the new switching device are collectively referred to as the terminal. Migration; especially in the scenario of downlinking the wireless WIFI network, as the user moves continuously, terminal migration will occur frequently.

During the migration, the terminal will be disconnected. For users, the disconnection time should be as short as possible to meet the continuous flow requirement in frequent migration scenarios. Therefore, how to maximize the migration speed and reduce the interruption time has become an urgent problem to be solved.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a method and an apparatus for accelerating terminal migration, which are used to solve the problem in the prior art that the terminal migration time is too long, resulting in an excessively long disconnection time.

According to an embodiment of the present invention, a method for accelerating terminal migration is provided, and the method is applied to a switching device, including:

After the media access control MAC authentication when the terminal accesses the switching device for the first time is passed, the Internet Protocol address IP and the media access control address MAC of the terminal are stored in the chip as global user entries; and

The MAC authentication module of the switching device sends an address resolution protocol ARP probe message to the terminal to learn ARP entries.

Optionally, the MAC authentication of the terminal includes:

After the chip learns the MAC address of the terminal, it sends a fast MAC address notification to the MAC authentication module of the switching device;

The MAC authentication module initiates MAC authentication.

Optionally, the method further includes:

When the access port PORT of the terminal changes, trigger the MAC violation event of the chip to send a migration notification to the MAC authentication module of the switching device;

After receiving the relocation announcement, the MAC authentication module sends an address resolution protocol ARP probe message to the terminal to learn ARP entries.

Optionally, the MAC authentication module sends an ARP probe packet to the terminal to learn ARP entries, including:

The MAC authentication module sends an ARP detection message to the terminal;

The terminal receives the ARP response message returned by the ARP detection message and performs ARP entry learning.

An embodiment of the present invention further provides an apparatus for accelerating terminal migration, the apparatus is applied to a switching device, and includes: a global user entry generation module and a MAC authentication module; wherein,

The global user entry generation module is used to use the terminal's Internet Protocol address IP and media access control address MAC as the global user entry after the MAC authentication when the terminal accesses the switching device for the first time is passed stored in the chip;

The MAC authentication module is used for sending an address resolution protocol ARP detection message to the terminal to learn ARP entries after the terminal has passed the MAC authentication when accessing the switching device for the first time.

Optionally, the apparatus further includes: a first sending module, configured to send a fast MAC address notification to the MAC authentication module of the switching device after the chip learns the MAC address of the terminal;

The MAC authentication module is further configured to initiate MAC authentication after receiving the fast MAC address announcement.

Optionally, the apparatus further includes: a triggering module configured to trigger a MAC violation event of the chip to send a migration notification to the MAC authentication module of the switching device when the access port PORT of the terminal changes ;

The MAC authentication module is further configured to send an address resolution protocol ARP probe message to the terminal after receiving the relocation announcement to learn ARP entries.

Optionally, the MAC authentication module is configured to send an ARP probe packet to the terminal to learn ARP entries, and is specifically configured to: send an ARP probe packet to the terminal; receive the terminal according to the The ARP response packet returned by the ARP probe packet is used to learn ARP entries.

According to an embodiment of the present invention, an electronic device is also provided, the electronic device includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus;

memory for storing computer programs;

The processor is configured to implement the above method steps when executing the program stored in the memory.

According to an embodiment of the present invention, a computer-readable storage medium is further provided, where a computer program is stored in the computer-readable storage medium, and the computer program implements the above method steps when executed by a processor.

The beneficial effects of the present invention are as follows:

The method and device for accelerating terminal migration provided by the embodiments of the present invention, after the MAC authentication when the terminal accesses the switching device for the first time is passed, the Internet Protocol address IP and the media access control address MAC address of the terminal are passed. It is stored in the chip as a global user entry; and the MAC authentication module of the switching device sends an address resolution protocol ARP detection message to the terminal to learn the ARP entry. After the terminal accesses the network, the correct forwarding of the packet does not depend on the PORT information of the access port. Therefore, when the terminal accesses the switching device for the first time, the switching device in this embodiment of the present invention only uses the IP and MAC as the global user entry. The information is stored in the chip. When forwarding packets later, it only needs to match the global user entry. In this way, when the terminal migrates within the same switching device, since the global user entry does not store PORT information, it is avoided. The addition and deletion of hardware chip table entries reduces the time-consuming of migration; and when the switching device determines that a new terminal is connected, after the terminal MAC address authentication is passed, it will actively send an ARP probe packet to the terminal for ARP Compared with passively waiting for the terminal to initiate ARP learning, the learning of table entries can complete the learning of ARP table entries more quickly, speed up the migration speed, reduce the interruption time, and improve the reliability of services.

Description of drawings

1 is a flowchart of a method for accelerating terminal migration in an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an apparatus for accelerating terminal migration in an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of an electronic device shown in this application.

Detailed ways

Generally speaking, device migration includes two situations: intra-device migration and inter-device migration. The specific process is as follows:

1. In-device migration: The switching device accessed by the terminal remains unchanged, but only the interface of the connected switching device changes. At this time, the connected switching device first kicks off the original online user and deletes the user entry in the chip. , and then go online again to add a new user entry, and update the MAC table and the Address Resolution Protocol (ARP) table.

2. Migration between devices: The switching device accessed by the terminal changes. The new switching device first learns the MAC address, and then adds a new user entry after the MAC authentication is passed, and updates the new user entry to the MAC table and ARP table.

Regardless of intra-device migration or inter-device migration, the normal forwarding of packets with MAC authentication enabled depends not only on the user entry of the hardware chip, but also on the MAC address table and the Address Resolution Protocol (ARP) table. The establishment time of the entry will also affect the disconnection time after the migration. Therefore, in view of the problem of the disconnection time process caused by the excessively long terminal migration process in the prior art, it can be improved by accelerating the establishment of various forwarding entries after the migration. Therefore, the embodiment of the present invention provides a kind of acceleration method of terminal migration, the method is applied to switching equipment, by setting the user entry as a global user entry, and the switching equipment actively initiates an ARP table when it is determined that a new terminal is added. Instead of passively waiting for the terminal to initiate, to realize the rapid establishment of forwarding entries, the specific process is shown in Figure 1, and the execution steps are as follows:

Step 101, after the MAC authentication when the terminal accesses the switching device for the first time passes, the Internet Protocol address IP and the media access control address MAC of the terminal are stored in the chip as global user entries;

Specifically, when the switching device performs user forwarding, it does not rely on the PORT information. Therefore, in the embodiment of the present invention, the switching device only stores the IP and MAC of the terminal as the information of the global user entry in the chip, and then forwards the packet later. , it is only necessary to match the IP and MAC in the global user entry to complete packet forwarding. Therefore, in this embodiment of the present invention, the global user entry does not need to set PORT information. During migration, since the global user table entry does not store PORT information, that is, the global user table entry does not change at this time, thus avoiding the addition and deletion of hardware chip table entries and reducing the time-consuming of migration.

Step 102, the MAC authentication module of the switching device sends an address resolution protocol ARP probe message to the terminal to learn ARP entries.

After the terminal's MAC address authentication is passed, the MAC address authentication module actively sends an ARP probe message to the terminal to learn ARP entries. Compared with passively waiting for the terminal to initiate ARP learning, the MAC address authentication module has better stability and processing performance. higher, the learning of ARP entries can be completed more quickly.

It should be understood that step 101 and step 102 do not have a strict sequential execution order, and may also be performed in parallel.

Wherein, the MAC authentication of the terminal includes:

After the chip learns the MAC address of the terminal, it sends a fast MAC address notification to the MAC authentication module of the switching device;

The MAC authentication module initiates MAC authentication; here, after receiving the fast MAC address announcement, the MAC authentication module can directly obtain the MAC address from the fast MAC address announcement and perform MAC authentication. The address is notified to the MAC address management module, such as the bridge module, and then the MAC address management module is notified to the MAC authentication module, which reduces the processing flow of other modules in the middle, and can complete the device migration more quickly.

Optionally, the method further includes:

When the access port PORT of the terminal changes, a MAC violation event of the chip is triggered to send a migration notification to the MAC authentication module of the switching device; here, the MAC violation event is triggered by the change of the terminal PORT When the MAC violation event is triggered, a migration notification will be sent to inform the MAC authentication module that it needs to re-learn ARP entries.

After receiving the relocation announcement, the MAC authentication module sends an address resolution protocol ARP probe message to the terminal to learn ARP entries.

Optionally, the MAC authentication module sends an ARP probe packet to the terminal to learn ARP entries, including:

The MAC authentication module sends an ARP detection message to the terminal;

The terminal receives the ARP response message returned by the ARP detection message and performs ARP entry learning.

In the acceleration method for terminal migration provided by the embodiment of the present invention, after the MAC authentication when the terminal accesses the switching device for the first time is passed, the Internet Protocol address IP and the media access control address MAC of the terminal are used as the global The user entry is stored in the chip; and the MAC authentication module of the switching device sends an address resolution protocol ARP probe message to the terminal to learn the ARP entry. After the terminal accesses the network, the correct forwarding of the packet does not depend on the PORT information of the access port. Therefore, when the terminal accesses the switching device for the first time, the switching device in this embodiment of the present invention only uses IP and MAC as the global user entry. The information is stored in the chip. When forwarding packets later, it only needs to match the global user entry. In this way, when the terminal migrates within the same switching device, since the global user entry does not store PORT information, it is avoided. The addition and deletion of hardware chip entries reduces the time-consuming of migration; and when the switching device determines that there is a new terminal access, after the terminal MAC address authentication is passed, it will actively send an ARP detection packet to the terminal for ARP Compared with passively waiting for the terminal to initiate ARP learning, the learning of table entries can quickly complete the learning of ARP table entries, speed up the migration speed, reduce the interruption time, and improve the reliability of services.

Based on the same inventive concept, an embodiment of the present invention provides an acceleration device for terminal migration, which can be applied to a switching device. The structure is shown in FIG. 2 , including: a global user entry generation module 21 and a MAC authentication module 22; wherein ,

The global user table entry generation module 21 is configured to use the terminal's Internet Protocol address IP and media access control address MAC as the global user table after the terminal's first access to the switching device has passed the MAC authentication. The item is stored in the chip; specifically, when the switching device performs user forwarding, it does not rely on the PORT information. Therefore, in the embodiment of the present invention, the switching device only stores the IP and MAC of the terminal as the information of the global user table entry into the chip, When forwarding a packet subsequently, it only needs to match the IP and MAC of the global user entry to complete the packet forwarding. Therefore, in this embodiment of the present invention, the global user entry does not need to set PORT information. In this way, when the terminal When migrating within the same switching device, since the global user entry does not store PORT information, that is, the global user entry does not change at this time, thus avoiding the addition and deletion of hardware chip entries and reducing the migration time. .

The MAC authentication module 22 is configured to send an address resolution protocol ARP detection message to the terminal to learn ARP entries after the terminal has passed the MAC authentication when accessing the switching device for the first time. After the terminal's MAC address authentication is passed, the MAC address authentication module actively sends an ARP probe message to the terminal to learn ARP entries. Compared with passively waiting for the terminal to initiate ARP learning, the MAC address authentication module has better stability and processing performance. higher, the learning of ARP entries can be completed more quickly.

Optionally, the apparatus further includes: a first sending module, configured to send a fast MAC address notification to the MAC authentication module of the switching device after the chip learns the MAC address of the terminal;

The MAC authentication module is further configured to initiate MAC authentication after receiving the fast MAC address announcement. Here, after receiving the fast MAC address announcement, the MAC authentication module can directly obtain the MAC address from the fast MAC address announcement and perform MAC authentication. Compared with the chip notifying the MAC address to the MAC address management module, such as The bridege module is then notified by the MAC address management module to the MAC authentication module, which reduces the processing flow of other intermediate modules and can complete the device migration more quickly.

Optionally, the apparatus further includes: a triggering module configured to trigger a MAC violation event of the chip to send a migration notification to the MAC authentication module of the switching device when the access port PORT of the terminal changes Here, the MAC violation event refers to an event triggered by the change of the terminal PORT. When the MAC violation event is triggered, a migration notification will be sent to inform the MAC authentication module that it needs to re-learn ARP entries.

The MAC authentication module is further configured to send an address resolution protocol ARP probe message to the terminal after receiving the relocation announcement to learn ARP entries.

Optionally, the MAC authentication module is configured to send an ARP probe packet to the terminal to learn ARP entries, and is specifically configured to: send an ARP probe packet to the terminal; receive the terminal according to the The ARP response packet returned by the ARP probe packet is used to learn ARP entries.

It should be understood that the implementation principle and process of the apparatus for accelerating terminal migration provided by the embodiment of the present invention are similar to the above-mentioned FIG. 1 and the embodiment shown, and details are not described herein again.

The method and device for accelerating terminal migration provided by the embodiments of the present invention, after the MAC authentication when the terminal accesses the switching device for the first time is passed, the Internet Protocol address IP and the media access control address MAC address of the terminal are passed. It is stored in the chip as a global user entry; and the MAC authentication module of the switching device sends an address resolution protocol ARP probe message to the terminal to learn the ARP entry. After the terminal accesses the network, the correct forwarding of the packet does not depend on the PORT information of the access port. Therefore, when the terminal accesses the switching device for the first time, the switching device in this embodiment of the present invention only uses IP and MAC as the global user entry. The information is stored in the chip. When forwarding packets later, it only needs to match the global user entry. In this way, when the terminal migrates within the same switching device, since the global user entry does not store PORT information, it is avoided. The addition and deletion of hardware chip entries reduces the time-consuming of migration; and when the switching device determines that there is a new terminal access, after the terminal MAC address authentication is passed, it will actively send an ARP detection packet to the terminal for ARP Compared with passively waiting for the terminal to initiate ARP learning, the learning of table entries can quickly complete the learning of ARP table entries, speed up the migration speed, reduce the interruption time, and improve the reliability of services.

An embodiment of the present application further provides an electronic device, as shown in FIG. 3 , including a processor 510, a communication interface 520, a memory 530, and a communication bus 540, wherein the processor 510, the communication interface 520, and the memory 530 pass through the communication bus 540 completes the mutual communication.

a memory 530 for storing computer programs;

The processor 510 is configured to implement the acceleration method for terminal migration described in any one of the foregoing embodiments when executing the program stored in the memory 530 .

The communication interface 520 is used for communication between the above-mentioned electronic device and other devices.

The memory may include random access memory (Random Access Memory, RAM), and may also include non-volatile memory (Non-Volatile Memory, NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

The above-mentioned processor may be a general-purpose processor, including a central processing unit (Central Processing Unit, CPU), a network processor (Network Processor, NP), etc.; may also be a digital signal processor (Digital Signal Processing, DSP), an application-specific integrated circuit (Application Specific Integrated Circuit, ASIC), Field-Programmable Gate Array (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components.

In this solution, the switching device only stores the IP and MAC as the information of the global user entry in the chip. When forwarding packets later, it only needs to match the global user entry. In this way, when the terminal migrates within the same switching device When the PORT information is not stored in the global user table, the operation of adding and deleting hardware chip table entries is avoided, and the migration time is reduced. Moreover, when the switching device determines that a new terminal is connected, the MAC address of the terminal is authenticated. After passing, it actively sends ARP detection packets to the terminal to learn ARP entries. Compared with passively waiting for the terminal to initiate ARP learning, the learning of ARP entries can be completed quickly, which speeds up migration and reduces interruptions. Streaming duration improves service reliability.

Correspondingly, an embodiment of the present application further provides a computer-readable storage medium, where instructions are stored in the computer-readable storage medium, and when the computer-readable storage medium runs on a computer, the computer enables the computer to perform the terminal migration described in any of the foregoing embodiments. acceleration method.

In this solution, the switching device only stores the IP and MAC as the information of the global user entry in the chip. When forwarding packets later, it only needs to match the global user entry. In this way, when the terminal migrates within the same switching device When the PORT information is not stored in the global user table, the operation of adding and deleting hardware chip table entries is avoided, and the migration time is reduced. Moreover, when the switching device determines that a new terminal is connected, the MAC address of the terminal is authenticated. After passing, it actively sends ARP detection packets to the terminal to learn ARP entries. Compared with passively waiting for the terminal to initiate ARP learning, the learning of ARP entries can be completed quickly, which speeds up migration and reduces interruptions. Streaming duration improves service reliability.

Those of ordinary skill in the art can understand that the accompanying drawing is only a schematic diagram of an embodiment, and the modules or processes in the accompanying drawing are not necessarily necessary to implement the present invention.

From the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software plus a necessary general hardware platform. Based on this understanding, the technical solutions of the present invention can be embodied in the form of software products in essence or the parts that make contributions to the prior art. The computer software products can be stored in storage media, such as ROM/RAM, magnetic disks, etc. , CD, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of the present invention.

Each embodiment in this specification is described in a progressive manner, and the same and similar parts between the various embodiments may be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the apparatus or system embodiments, since they are basically similar to the method embodiments, the description is relatively simple, and reference may be made to some descriptions of the method embodiments for related parts. The apparatus and system embodiments described above are only illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, It can be located in one place, or it can be distributed over multiple network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution in this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort.

In addition, in some of the processes described in the above embodiments and the accompanying drawings, multiple operations appearing in a specific order are included, but it should be clearly understood that these operations may be performed out of the order in which they appear in this document or performed in parallel , the sequence numbers of the operations, such as 201, 202, 203, etc., are only used to distinguish different operations, and the sequence numbers themselves do not represent any execution order. Additionally, these flows may include more or fewer operations, and these operations may be performed sequentially or in parallel. It should be noted that the descriptions such as "first" and "second" in this document are used to distinguish different messages, devices, modules, etc., and do not represent a sequence, nor do they limit "first" and "second" are different types.

The device embodiments described above are only illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed over multiple network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution in this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block in the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to the processor of a general purpose computer, special purpose computer, embedded processor or other programmable data processing device to produce a machine such that the instructions executed by the processor of the computer or other programmable data processing device produce Means for implementing the functions specified in a flow or flow of a flowchart and/or a block or blocks of a block diagram.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions The apparatus implements the functions specified in the flow or flow of the flowcharts and/or the block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in the flow or blocks of the flowcharts and/or the block or blocks of the block diagrams.

Although alternative embodiments of the present invention have been described, additional changes and modifications to these embodiments may occur to those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be construed to include alternative embodiments and all changes and modifications that fall within the scope of the present invention.

Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the embodiments of the present invention. Thus, provided that these modifications and variations of the embodiments of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims (10)

1. A method for accelerating terminal migration, wherein the method is applied to a switching device, comprising: After the media access control MAC authentication when the terminal accesses the switching device for the first time is passed, the Internet Protocol address IP and the media access control address MAC of the terminal are stored in the chip as global user entries; and The MAC authentication module of the switching device sends an address resolution protocol ARP probe message to the terminal to learn ARP entries. 2. The method according to claim 1, wherein the MAC authentication of the terminal comprises: After the chip learns the MAC address of the terminal, it sends a fast MAC address notification to the MAC authentication module of the switching device; The MAC authentication module initiates MAC authentication. 3. The method according to claim 1, wherein the method further comprises: When the access port PORT of the terminal changes, trigger the MAC violation event of the chip to send a migration notification to the MAC authentication module of the switching device; After receiving the relocation announcement, the MAC authentication module sends an address resolution protocol ARP probe message to the terminal to learn ARP entries. 4. The method according to any one of claims 1 to 3, wherein the MAC authentication module sends an ARP probe message to the terminal to learn ARP entries, comprising: The MAC authentication module sends an ARP detection message to the terminal; The terminal receives the ARP response message returned by the ARP detection message and performs ARP entry learning. 5. An acceleration device for terminal migration, wherein the device is applied to a switching device, comprising: a global user entry generation module and a MAC authentication module; wherein, The global user entry generation module is used to use the terminal's Internet Protocol address IP and media access control address MAC as the global user entry after the MAC authentication when the terminal accesses the switching device for the first time is passed stored in the chip; The MAC authentication module is used for sending an address resolution protocol ARP detection message to the terminal to learn ARP entries after the terminal has passed the MAC authentication when accessing the switching device for the first time. 6 . The device according to claim 5 , wherein the device further comprises: a first sending module, configured to send a fast MAC address notification to the terminal after the chip learns the MAC address of the terminal. 7 . The MAC authentication module of the switching device; The MAC authentication module is further configured to initiate MAC authentication after receiving the fast MAC address announcement. 7 . The device according to claim 5 , wherein the device further comprises: a triggering module, configured to trigger a MAC violation event of the chip to send when the access port PORT of the terminal changes. 8 . migrating notification to the MAC authentication module of the switching device; The MAC authentication module is further configured to send an address resolution protocol ARP probe message to the terminal after receiving the relocation announcement to learn ARP entries. 8. The apparatus according to any one of claims 5 to 7, wherein the MAC authentication module is configured to send an ARP probe message to the terminal to learn ARP entries, and is specifically configured to: send an ARP Send the detection message to the terminal; and receive the ARP response message returned by the terminal according to the ARP detection message to learn ARP entries. 9. An electronic device, characterized in that the electronic device comprises a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; memory for storing computer programs; The processor is configured to implement the method steps of any one of claims 1-4 when executing the program stored in the memory. 10. A computer-readable storage medium, wherein a computer program is stored in the computer-readable storage medium, and when the computer program is executed by a processor, the method steps of any one of claims 1-4 are implemented.

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