阅读说明：本技术 一种数据分流方法、装置及相关设备 (Data distribution method, device and related equipment ) 是由 李有 秦海中 于 2021-06-28 设计创作，主要内容包括：本申请公开了一种数据分流方法,包括获取目标数据包,并确定所述目标数据包的目的地址；对所述目的地址进行哈希运算,获得哈希值；根据各数据链路的流量传输比例构建指向所述数据链路的路由分流数组；根据所述哈希值和所述路由分流数组计算获得目标数组元素；利用所述目标数组元素对应的数据链路将所述目标数据包发送至所述目的地址；该数据分流方法可以根据实际场景的路径带宽差异对流量进行合理分流,以充分发挥设备的数据转发性能。本申请还公开了一种数据分流装置、系统及计算机可读存储介质,均具有上述有益效果。(The application discloses a data distribution method, which comprises the steps of obtaining a target data packet and determining a destination address of the target data packet; carrying out Hash operation on the destination address to obtain a Hash value; constructing a route distribution array pointing to each data link according to the traffic transmission proportion of the data link; calculating according to the hash value and the routing distribution array to obtain a target array element; sending the target data packet to the destination address by using a data link corresponding to the target array element; the data distribution method can reasonably distribute the flow according to the path bandwidth difference of the actual scene so as to fully play the data forwarding performance of the equipment. The application also discloses a data distribution device, a system and a computer readable storage medium, which have the beneficial effects.)

1. A data distribution method is characterized by comprising the following steps:

acquiring a target data packet and determining a destination address of the target data packet;

carrying out Hash operation on the destination address to obtain a Hash value;

constructing a route distribution array pointing to each data link according to the traffic transmission proportion of the data link;

calculating according to the hash value and the routing distribution array to obtain a target array element;

and sending the target data packet to the destination address by using the data link corresponding to the target array element.

2. The data splitting method according to claim 1, wherein the performing a hash operation on the destination address to obtain a hash value includes:

and carrying out exclusive OR operation on each byte in the destination address to obtain the hash value.

3. The data offloading method of claim 1, wherein the calculating a target array element according to the hash value and the route offload array comprises:

counting the number of elements of the routing shunt array;

and performing remainder operation on the element number by using the hash value to obtain the target array element.

4. The data offloading method according to any one of claims 1 through 3, further comprising:

when receiving the link failure information, constructing a new route distribution array according to the flow transmission proportion of each residual data link;

calculating according to the hash value and the new route distribution array to obtain a new target array element;

and sending the target data packet to the destination address by using the data link corresponding to the new target array element.

5. The data offloading method of claim 1, wherein the destination address is an IP address, a MAC address, or a port address.

6. A data offloading device, comprising:

the data acquisition module is used for acquiring a target data packet and determining a destination address of the target data packet;

the hash operation module is used for carrying out hash operation on the destination address to obtain a hash value;

the array construction module is used for constructing a route distribution array pointing to the data links according to the flow transmission proportion of each data link;

the array determining module is used for calculating and obtaining a target array element according to the hash value and the routing distribution array;

and the data sending module is used for sending the target data packet to the destination address by using the data link corresponding to the target array element.

7. The data offloading device according to claim 6, wherein the hash operation module is specifically configured to perform an exclusive-or operation on each byte in the destination address to obtain the hash value.

8. The data offloading device according to claim 6, wherein the array construction module is specifically configured to count a number of elements of the route offloading array; and performing remainder operation on the element number by using the hash value to obtain the target array element.

9. A data offloading system, comprising:

a memory for storing a computer program;

a processor for implementing the steps of the data offloading method according to any of claims 1 to 5 when executing the computer program.

10. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, implements the steps of the data offloading method according to any one of claims 1 to 5.

Technical Field

The present application relates to the field of computer data processing technologies, and in particular, to a data offloading method, and further, to a data offloading device, a data offloading system, and a computer-readable storage medium.

Background

With the development of computers, more and more scientific and technical products are used in life, and the requirements on background support services such as network transmission, server capacity, response speed and the like are higher and higher while the diversity and convenience of life are enriched. Even though the performance of the current hardware devices is very strong, the capability provided by a single physical resource is limited, and for the processing of the same service, many physical devices are often required to be supported together for completion. Particularly, in the current cloud computing scenario with wide application, one data center often needs a plurality of gateway nodes to establish a plurality of gateway clusters to provide three-layer network forwarding service. In a gateway node cluster, all gateway nodes may provide the same forwarding service. Although the purpose of the data flow is the same, the flow paths are not the same, and the flow needs to be split. The shunting has the function of distributing the paths through which the flow flows, the three-layer flow needs to keep the stateful property of the flow, and in popular terms, the flow with the same property needs to keep the same path for forwarding.

Currently, the existing mainstream shunting mode is an equivalent Routing (ECMP) mode, and the method provides various shunting algorithms, such as quintuple-based and MAC-based. However, the practical use effect is that the flow allocated by multiple paths is the same, which has a disadvantage in a special scene. Because the forwarding capability provided by each path may be different in an actual usage scenario, if forwarding is provided according to the minimum path bandwidth, waste of device resources may be caused; if the forwarding is provided according to the maximum path bandwidth, some paths are congested and packet loss is caused, so that service interruption is caused.

This patent provides an unbalanced load sharing algorithm for this scenario. Under the condition of ensuring that the back-and-forth paths with the same flow are consistent, the flow can be shunted according to the path bandwidth difference of the actual scene and the specific proportion, so that the forwarding performance of the equipment is fully exerted.

Therefore, how to reasonably distribute traffic according to the path bandwidth difference of the actual scene and fully exert the forwarding performance of the device is a problem to be solved urgently by those skilled in the art.

Disclosure of Invention

The data distribution method can reasonably distribute the flow according to the path bandwidth difference of the actual scene so as to fully play the data forwarding performance of the equipment; another object of the present application is to provide a data offloading device, a system and a computer readable storage medium, all of which have the above advantages.

In a first aspect, the present application provides a data offloading method, including:

acquiring a target data packet and determining a destination address of the target data packet;

carrying out Hash operation on the destination address to obtain a Hash value;

constructing a route distribution array pointing to each data link according to the traffic transmission proportion of the data link;

calculating according to the hash value and the routing distribution array to obtain a target array element;

and sending the target data packet to the destination address by using the data link corresponding to the target array element.

Preferably, the performing a hash operation on the destination address to obtain a hash value includes:

and carrying out exclusive OR operation on each byte in the destination address to obtain the hash value.

Preferably, the obtaining of the target array element by calculating according to the hash value and the route splitting array includes:

counting the number of elements of the routing shunt array;

and performing remainder operation on the element number by using the hash value to obtain the target array element.

Preferably, the data offloading method further includes:

when receiving the link failure information, constructing a new route distribution array according to the flow transmission proportion of each residual data link;

calculating according to the hash value and the new route distribution array to obtain a new target array element;

and sending the target data packet to the destination address by using the data link corresponding to the new target array element.

Preferably, the destination address is an IP address, or a MAC address, or a port address.

In a second aspect, the present application also discloses a data offloading device, including:

the data acquisition module is used for acquiring a target data packet and determining a destination address of the target data packet;

the hash operation module is used for carrying out hash operation on the destination address to obtain a hash value;

the array construction module is used for constructing a route distribution array pointing to the data links according to the flow transmission proportion of each data link;

the array determining module is used for calculating and obtaining a target array element according to the hash value and the routing distribution array;

and the data sending module is used for sending the target data packet to the destination address by using the data link corresponding to the target array element.

Preferably, the hash operation module is specifically configured to perform an exclusive or operation on each byte in the destination address to obtain the hash value.

Preferably, the array construction module is specifically configured to count the number of elements of the route splitting array; and performing remainder operation on the element number by using the hash value to obtain the target array element.

In a third aspect, the present application further discloses a data offloading system, including:

a memory for storing a computer program;

a processor, configured to implement the steps of any of the data offloading methods described above when executing the computer program.

In a fourth aspect, the present application further discloses a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps of any of the data offloading methods described above.

The data distribution method comprises the steps of obtaining a target data packet and determining a destination address of the target data packet; carrying out Hash operation on the destination address to obtain a Hash value; constructing a route distribution array pointing to each data link according to the traffic transmission proportion of the data link; calculating according to the hash value and the routing distribution array to obtain a target array element; and sending the target data packet to the destination address by using the data link corresponding to the target array element.

Therefore, the data distribution method provided by the application constructs the routing distribution array which can be used for realizing flow transmission according to the proportion according to the flow transmission proportion of each data link, and further determines the data link corresponding to the data packet by combining the destination address of the data packet to be transmitted, so as to realize the transmission of the data packet.

The data distribution device, the data distribution system and the computer readable storage medium provided by the application all have the beneficial effects, and are not described herein again.

Drawings

In order to more clearly illustrate the technical solutions in the prior art and the embodiments of the present application, the drawings that are needed to be used in the description of the prior art and the embodiments of the present application will be briefly described below. Of course, the following description of the drawings related to the embodiments of the present application is only a part of the embodiments of the present application, and it will be obvious to those skilled in the art that other drawings can be obtained from the provided drawings without any creative effort, and the obtained other drawings also belong to the protection scope of the present application.

Fig. 1 is a schematic flow chart of a data offloading method provided in the present application;

fig. 2 is a gateway cluster topology diagram provided in the present application;

fig. 3 is a schematic flow chart of another data offloading method provided in the present application;

fig. 4 is a schematic structural diagram of a data offloading device provided in the present application;

fig. 5 is a schematic structural diagram of a data offloading system provided in the present application.

Detailed Description

The core of the application is to provide a data distribution method, which can reasonably distribute traffic according to the path bandwidth difference of an actual scene so as to fully exert the data forwarding performance of equipment; another core of the present application is to provide a data offloading device, a system and a computer readable storage medium, which also have the above beneficial effects.

In order to more clearly and completely describe the technical solutions in the embodiments of the present application, the technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The embodiment of the application provides a data distribution method.

Referring to fig. 1, fig. 1 is a schematic flow chart of a data offloading method provided in the present application, where the data offloading method may include:

s101: acquiring a target data packet and determining a destination address of the target data packet;

this step aims to achieve the acquisition of the target data packet and to determine its destination address. The destination data packet is a data packet that needs to be forwarded or transmitted, and the destination address is an address that the destination data packet needs to access. Specifically, when a target data packet is received, the destination address of the target data packet may be determined by analyzing the target data packet, or the destination address may be received together with the target data packet; the target data packet may be a data packet sent by other devices, or may also be a data packet sent by the user based on the user front end, which is not limited in the present application.

As a preferred embodiment, the destination address may be an IP address, or a MAC address, or a port address.

It is understood that the specific type of the destination address is not unique, and the destination data packet can be sent to the corresponding destination address according to actual requirements, including but not limited to an IP address, a MAC address, a port address, and the like.

S102: carrying out Hash operation on the destination address to obtain a Hash value;

the step aims to realize the hash operation of the destination address, and a corresponding hash value is obtained by performing the hash operation on the destination address. The hash operation may be a hash operation on each byte bit of the destination address. It can be understood that the difference of the destination address types does not affect the implementation of the present technical solution, and the corresponding hash value can be obtained by performing hash operation on the destination address.

As a preferred embodiment, the performing the hash operation on the destination address to obtain the hash value may include: and carrying out exclusive OR operation on each byte in the destination address to obtain a hash value.

The preferred embodiment provides a hash operation method for a destination address, which is to perform an exclusive or operation on each byte in the destination address to obtain a corresponding hash value. The hash value can be calculated in this way regardless of the IP address, the MAC address, or the port address. For example, if the destination IP address of the destination packet is 110.242.68.4, the xor operation is performed on IP bytes, and there are: 1^1^10^110^242^68^4 ^ 215, namely the hash value is 215.

S103: constructing a route distribution array pointing to the data links according to the traffic transmission proportion of each data link;

the step aims to realize the construction of the route shunting array, namely the construction is carried out according to the traffic transmission proportion of each data link in the system, wherein the traffic transmission proportion can be the link bandwidth proportion. In the specific implementation process, the link bandwidth of each data link is firstly obtained, the sum of the link bandwidths of all the data links is further calculated, and the quotient of the sum and the greatest common divisor of all the link bandwidths is calculated, wherein the quotient is the number of elements in the route splitting array, and each element in the array points to the corresponding data link. For example, if there are three data links in the system, and the bandwidths are 40M/s, 25M/s, and 100M/s, respectively, the number of elements in the route splitting array is (40+25+100)/5 ═ 33, so that a route splitting array a [33] can be constructed; further, assigning values to each element in the array according to the traffic transmission ratio of the data link, wherein the link bandwidth ratio of each data link is 8:5:20, and the following steps are performed: a [0-7] points to a data link with a link bandwidth of 40M/s, A [8-12] points to a data link with a link bandwidth of 25M/s, and A [13-32] points to a data link with a link bandwidth of 100M/s.

S104: calculating according to the hash value and the routing distribution array to obtain a target array element;

the step aims to realize the calculation of the target routing shunt array, and the target array element can be calculated and obtained according to the hash value of the target address and the routing shunt array, wherein the target array element is used for realizing the determination of the target data link, and the data link pointed by the target array element is the target data link, namely the data link used for realizing the transmission of the target data packet.

As a preferred embodiment, the obtaining of the target array element according to the hash value and the route splitting array calculation may include: counting the number of elements of the routing shunt array; and carrying out remainder operation on the number of the elements by utilizing the hash value to obtain the target array elements.

The preferred embodiment provides a method for realizing calculation of target array elements. Specifically, the number of elements (element number) in the route split array is counted first, and further, the element number is subjected to a remainder operation by using the hash value of the destination address to obtain a corresponding value, which is the target array element. For example, the hash value of the target address 110.242.68.4 is 215, and for the example of three links in the system (the bandwidths are 40M/s, 25M/s, and 100M/s, respectively), 215 takes the remainder of the element number 33 to obtain 17, and then the target array element is a [17 ].

S105: and sending the target data packet to a destination address by using a data link corresponding to the target array element.

Specifically, after the target array element is determined, the target data link to which the target data packet points is determined according to the target array element, and thus the target data packet is sent to the destination address by using the target data link. As described above, the destination array element is A [17] and points to a data link with a link bandwidth of 100M/s, so that the destination data packet can be sent to the destination address using the data link with the link bandwidth of 100M/s.

As a preferred embodiment, the data offloading method may further include: when receiving the link failure information, constructing a new route distribution array according to the flow transmission proportion of each residual data link; calculating according to the hash value and the new route distribution array to obtain a new target array element; and sending the target data packet to the destination address by using the data link corresponding to the new target array element.

When the data link fails, a new route distribution array can be reconstructed by using the remaining data links which normally operate, so that a new data link is determined, and the transmission of the target data packet is completed. Further, when the failed data link returns to normal, the new routing shunt array can be constructed again to transmit the target data packet. Therefore, under the condition of sufficient shunting, the quick switching of the fault is further realized, and the millisecond switching can be achieved by monitoring the state of the data link.

Therefore, the data distribution method provided by the application constructs the routing distribution array which can be used for realizing flow transmission according to the proportion according to the flow transmission proportion of each data link, and further determines the data link corresponding to the data packet by combining the destination address of the data packet to be transmitted, so as to realize the transmission of the data packet.

Based on the foregoing embodiments, the present application provides another data offloading method.

The embodiment of the application specifically introduces the data distribution method by taking three-layer forwarding load distribution based on a gateway cluster as an example.

Referring to fig. 2, fig. 2 is a gateway cluster topology diagram provided in the present application, where the topology diagram shows a data plane splitting effect. As shown in fig. 2, data traffic can be SNAT converted by three gateways gw1192.168.1.1, gw2192.168.1.2 and gw3192.168.1.3 to be sent to a physical gateway for accessing Internet. The data plane flow process is described below for the virtual machine on HV1 as an example.

When VM1 and VM2 need access to the Internet in hundredths, the source IP is 1.1.1.10 for www.baidu.com. According to fig. 2, since the visited non-home network segment IP is, three layers of forwarding are required, wherein three routes forwarded by one layer are respectively 0.0.0.0/0via 192.168.1.1, 0.0.0/0via192.168.1.2 and 0.0.0/24via 192.168.1.3, the three link bandwidths are all 100M/s, and according to a normal load splitting manner, 1: 1: 1, splitting, wherein link bandwidths when traffic is forwarded to a physical router after arriving at a gateway are respectively 40M/s, 25M/s and 100M/s, and it is conceivable that gw2 causes service exception due to link congestion packet loss when the traffic split to three gateways is greater than 25M/s; when the flow equally distributed to the three gateways is more than 40M/s, the gw1 and the gw2 cause abnormal service due to traffic congestion packet loss; the performance of gw3 is fully exploited when the traffic split to the three gateways equals 100M/s.

Based on this, according to the actual environment, the network administrator may perform flow splitting limitation on the traffic matching the three routes, so that the traffic reaching gw1(192.168.1.1) is 40 parts, the traffic reaching gw2(192.168.1.2) is 25 parts, and the traffic reaching gw3(192.168.2.3) is 100 parts, thereby reaching 40: 25: 100, in a ratio of one to the other. Furthermore, when the message sent from gw1 returns, the message still returns to gw1, the message sent from gw2 still returns to gw2, and the message sent from gw3 returns to gw3, so the round-trip traffic is forwarded according to the allocation ratio, and the device performance is fully exerted.

Further, referring to fig. 3, fig. 3 is a schematic flow chart of another data offloading method provided in the present application, and a specific implementation flow of the method is as follows:

1. with reference to fig. 2, when the gateway (1.1.1.1) on the HV device receives traffic arriving outside, it needs to forward to the gateway gw1, gw2 or gw3, at which time the diversion is needed.

2. The referenced elements (IP address based, MAC address based, port address based, other parameters) are determined according to the configured offload algorithm, here exemplified by the IP address, assuming the source IP is 1.1.1.10 and the destination IP is 110.242.68.4 (www.baidu.com).

3. Performing exclusive-or according to the IP byte bit, then: 1^1^10^110^242^68^4 ^ 215, obtain a value within 0 xFF.

4. According to the proportion A of the distribution flow: b: c calculating to obtain a specific value: (specific value ═ a + B + C)/greatest common divisor)), the proportion of the three gateway node traffic in fig. 2 is 40: 25: 100, whereby a specific value of 33((40+25+100)/5 ═ 33) was calculated. Further, an array ActiveList [33] of the route distribution is created according to the specific value 33, then the array is subjected to assignment operation according to the flow ratio, ActiveList [0-7] points to the route 0.0.0.0/0via 192.168.1.1, ActiveList [8-12] points to the route 0.0.0.0/0via 192.168.1.2, and ActiveList [13-32] points to 0.0.0.0/0via 192.168.1.3. Finally, the diversion calculation is carried out, the value 215 obtained by the exclusive OR in the step 3 is used for obtaining the value 17 after the 33 is left, and therefore, the route needing to be matched can be obtained by directly using ActiveList [17], namely the route corresponds to 0.0.0.0/0 via192.168.1.3.

5. When the gateway node fails, the data and the specific value of the ActiveList are adjusted. E.g., gw2, then the particular value is equal to 7((40+ 100)/20-7). Further, the value is assigned to the array ActiveList again, and ActiveList [0-1] points to the route 0.0.0.0/0via 192.168.1.1, and ActiveList [2-6] points to 0.0.0.0/0via 192.168.1.3. Finally, when the split calculation is carried out, the value 215 obtained by the exclusive OR in the step 3 is used for obtaining the remainder of 7 to obtain 5, so that the route needing to be matched can be obtained by directly using ActiveList [5], namely the route corresponds to 0.0.0.0/0via 192.168.1.3.

6. After the fault is recovered, the data and the specific value of the ActiveList can be readjusted, and then the flow can be shunted again.

7. The above example is three gateway nodes, but the scheme may support M + N gateway nodes, where M is active, N is inactive, and N may be equal to 0. Under the condition of sufficient shunting, the fault can be quickly switched, and millisecond switching can be achieved by monitoring the link state.

It can be seen that, according to the data offloading method provided in the embodiment of the present application, a route offloading array capable of implementing traffic transmission in proportion is constructed according to a traffic transmission ratio of each data link, and then a data link corresponding to a data packet is determined in combination with a destination address of the data packet to be transmitted, thereby implementing transmission of the data packet, thereby implementing reasonable offloading of traffic according to a traffic transmission difference of an actual scene, further fully playing data forwarding performance of a device, effectively avoiding problems of empty waste of part of devices and full load blocking of part of devices, and improving a device utilization rate.

To solve the above technical problem, the present application further provides a data offloading device, please refer to fig. 4, where fig. 4 is a schematic structural diagram of the data offloading device provided in the present application, and the data offloading device may include:

the data acquisition module 1 is used for acquiring a target data packet and determining a destination address of the target data packet;

the hash operation module 2 is used for carrying out hash operation on the destination address to obtain a hash value;

the array construction module 3 is used for constructing a route distribution array pointing to the data link according to the flow transmission proportion of each data link;

the array determining module 4 is used for calculating and obtaining a target array element according to the hash value and the routing distribution array;

and the data sending module 5 is configured to send the target data packet to the destination address by using the data link corresponding to the target array element.

It can be seen that, the data offloading device provided in this embodiment of the present application constructs a route offloading array capable of implementing traffic transmission in proportion according to a traffic transmission ratio of each data link, and then determines a data link corresponding to a data packet in combination with a destination address of the data packet to be transmitted, thereby implementing transmission of the data packet, thereby implementing reasonable offloading of traffic according to a traffic transmission difference of an actual scene, further fully playing data forwarding performance of a device, effectively avoiding problems of empty waste of part of devices and full load blocking of part of devices, and improving device utilization.

As a preferred embodiment, the hash operation module 2 may be specifically configured to perform an exclusive or operation on each byte in the destination address to obtain a hash value.

As a preferred embodiment, the array construction module 3 may be specifically configured to count the number of elements of the route splitting array; and carrying out remainder operation on the number of the elements by utilizing the hash value to obtain the target array elements.

As a preferred embodiment, the data offloading device may further include a failure re-offloading module, configured to, when receiving link failure information, construct a new routing offload array according to a traffic transmission ratio of each remaining data link; calculating according to the hash value and the new route distribution array to obtain a new target array element; and sending the target data packet to the destination address by using the data link corresponding to the new target array element.

As a preferred embodiment, the destination address may be an IP address, or a MAC address, or a port address.

For the introduction of the apparatus provided in the present application, please refer to the above method embodiments, which are not described herein again.

To solve the above technical problem, the present application further provides a data offloading system, please refer to fig. 5, where fig. 5 is a schematic structural diagram of the data offloading system provided in the present application, and the data offloading device may include:

a memory 10 for storing a computer program;

the processor 20, when executing the computer program, may implement the steps of any of the data offloading methods described above.

For the introduction of the system provided by the present application, please refer to the above method embodiment, which is not described herein again.

To solve the above problem, the present application further provides a computer-readable storage medium, where a computer program is stored, and when the computer program is executed by a processor, the steps of any one of the data offloading methods described above can be implemented.

The computer-readable storage medium may include: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

For the introduction of the computer-readable storage medium provided in the present application, please refer to the above method embodiments, which are not described herein again.

The embodiments are described in a progressive manner in the specification, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. The device disclosed by the embodiment corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

Those of skill would further appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both, and that the various illustrative components and steps have been described above generally in terms of their functionality in order to clearly illustrate this interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in Random Access Memory (RAM), memory, Read Only Memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

The technical solutions provided by the present application are described in detail above. The principles and embodiments of the present application are explained herein using specific examples, which are provided only to help understand the method and the core idea of the present application. It should be noted that, for those skilled in the art, without departing from the principle of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall into the protection scope of the present application.