CN109788078B

CN109788078B - Application server switching method, device and system

Info

Publication number: CN109788078B
Application number: CN201711116842.3A
Authority: CN
Inventors: 王辉; 孙德奎; 王秋红; 张春蕾
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-11-13
Filing date: 2017-11-13
Publication date: 2020-10-16
Anticipated expiration: 2037-11-13
Also published as: CN112291381B; CN109788078A; CN112291381A

Abstract

The application server switching method, device and system provided by the embodiment of the application server switching method, device and system can realize the timely switching of the application server in the scene that the terminal is switched from the source MEC platform to the target MEC platform for access, and the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform do not need to be subjected to adaptive development, so that conditions are created for the large-scale application of the MEC. The method comprises the following steps: the terminal receives a DNS refreshing message, wherein the DNS refreshing message carries a DNS record identifier and is used for indicating to refresh a source DNS record corresponding to the DNS record identifier; and the terminal refreshes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message to obtain the target DNS record.

Description

Application server switching method, device and system

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method, a device, and a system for switching an application server.

Background

Mobile Edge Computing (MEC) is a technology for deeply fusing an access network and internet services based on a 5rd generation (5G) evolution architecture. The method deploys the functions of service processing and resource scheduling of part of an Application Server (AS) and a mobile broadband (MBB) core network to the network edge close to an access network together, and provides reliable and extremely-low-delay service experience through service close to user processing.

Generally, to provide an ultimate business experience, application servers providing the same service need to be deployed on adjacent MEC platforms, and after a MEC platform switch occurs on a terminal, an accessed object can be quickly switched from a source application server deployed on a source MEC platform to a target application server deployed on a target MEC platform and providing the same service. In the prior art, when a terminal accesses a certain application server, the terminal generally accesses through a domain name of the application server. For example, assuming that the domain name of an application server is app.com, the process of the terminal accessing the application server is as follows: and step one, a user inputs app.com in a browser or directly opens a terminal application corresponding to the application server for access. And step two, the browser or the terminal application initiates a Domain Name System (DNS) request to obtain an Internet Protocol (IP) address corresponding to app.com. And step three, the terminal Operating System (OS) queries a local DNS cache, and if a DNS record corresponding to app.com is queried, the corresponding IP address is directly returned to the browser or the terminal application. Wherein, a mapping relation between a domain name and an IP address is a DNS record. And step four, if the DNS record corresponding to the app.com is not inquired in the step three, the terminal sends a DNS analysis request to the DNS server. And step five, after receiving a DNS analysis request from the terminal, the DNS server carries out DNS analysis, and sends the IP address corresponding to the app.com to the terminal through a DNS response message. And step six, after receiving a DNS analysis response from the DNS server, the terminal returns the IP address corresponding to the app.com to the browser or the terminal application, and simultaneously stores the corresponding DNS record in the terminal. The buffering time of the DNS record in the terminal may be set according to a Time To Live (TTL) parameter in the DNS response, or may be set by the OS or the terminal application. When the time for caching the DNS record in the terminal has expired, the DNS cache will be cleared or no longer valid. And step seven, the browser or the terminal application initiates a connection request to an application server corresponding to the IP address after obtaining the IP address corresponding to the app.com. Further, the application server may return the requested content to the terminal and display it by a browser or terminal application. And ending the process that the terminal accesses the application server. However, since the domain names of the application servers that provide the same service and are deployed on different MEC platforms are the same, and the corresponding IP addresses are different, after the terminal accesses a certain application server on the source MEC platform, the IP address in the DNS record stored by the terminal points to the application server deployed on the source MEC platform. Therefore, after the MEC platform switching of the subsequent terminal occurs, if the terminal still accesses through the domain name of the application server and the DNS record is still in the validity period, the terminal still accesses the application server on the source MEC platform according to the DNS record, and does not access the application server that provides the same service for the target MEC platform, thereby greatly affecting the business experience of the user. For example, if the IP addresses allocated to the application servers deployed on the source MEC platform and the target MEC platform are private network IP addresses, access failure of the application servers will be caused; if the IP addresses of the application servers deployed on the source MEC platform and the target MEC platform are public network IP addresses, the access path will be lengthened. To solve the above problems, the prior art provides the following two solutions:

the first scheme is to reduce the buffering time of the DNS record in the terminal by modifying the value of the TTL parameter in the DNS response message. Since the TTL parameter is used for representing the caching time of the DNS record in the terminal, after the TTL parameter is expired, the corresponding DNS record is removed or is no longer valid, so that when the terminal still accesses through the domain name of the application server, the application server with the same service is provided on the target MEC platform according to the process that the terminal accesses the application server, and therefore, the caching time of the DNS record in the terminal is reduced, and the switching of the application server can be accelerated. On one hand, however, even if the set TTL parameter is small, after the MEC platform handover occurs at the terminal, if the TTL parameter has not expired, the above problem still exists; on the other hand, if the value of the TTL parameter is too small, DNS resolution requests will be too frequent, and thus network pressure will be increased; in another aspect, some terminals may not determine the buffering time of the DNS record in the terminal according to the TTL parameter, and thus, modifying the value of the TTL parameter may not solve the above problem. Such as: an application on an android terminal can set the caching time of the DNS record in the terminal by itself, or even set to be always valid. That is, modifying the TTL parameter can only accelerate the switching of the application servers to a certain extent, which cannot solve the above problem fundamentally, and may cause side effects such as too frequent DNS resolution requests.

In the second scheme, the MEC switching information is obtained through interaction between the application server deployed on the MEC platform and the core network, and the application server switched on the MEC platform is switched through interaction between the application server deployed on the MEC platform and the terminal. However, in this solution, each application server deployed on the MEC platform needs to be adapted and developed first to support the application server to subscribe and receive MEC handover events from the core network and to support the application server and the terminal to interact with each other. Therefore, the cost and difficulty of the MEC are greatly increased, and the terminal application corresponding to the application server deployed on the MEC platform also needs to be adapted and developed to support the terminal to process the switching notification after receiving the switching notification of the application server, so that the willingness of an application manufacturer to use the MEC is influenced, and the large-scale application of the MEC is influenced.

Therefore, how to realize the timely switching of the application server in the scenario that the terminal is switched to access from the source MEC platform to the target MEC platform, and the adaptation development of the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform is not required, is a problem to be solved urgently at present.

Disclosure of Invention

The application server switching method, device and system provided by the embodiment of the application server switching method, device and system can realize the timely switching of the application server in the scene that the terminal is switched from the source MEC platform to the target MEC platform for access, and the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform do not need to be subjected to adaptive development, so that conditions are created for the large-scale application of the MEC.

In order to achieve the above purpose, the embodiments of the present application provide the following technical solutions:

in a first aspect, a method for switching an application server is provided, where the method is applied in a scenario where a terminal switches from a source mobile edge computing MEC platform to a target MEC platform for access, and the method includes: a terminal receives a Domain Name System (DNS) refreshing message, wherein the DNS refreshing message carries a DNS record identifier and is used for indicating and refreshing a source DNS record corresponding to the DNS record identifier, the source DNS record comprises a corresponding relation between a domain name of each application server in M application servers deployed on a source MEC platform and a corresponding source Internet Protocol (IP) address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer; and the terminal refreshes the source DNS record corresponding to the DNS record identifier according to the DNS refreshing message to obtain a target DNS record, wherein the target DNS record comprises the corresponding relation between the domain name of the application server which is also deployed on the target MEC platform in the M application servers and the corresponding target IP address, and the target IP address is the IP address associated with the target MEC platform. Based on the scheme, on one hand, after the MEC platform is switched, the source DNS record corresponding to the DNS record identifier can be refreshed in time to obtain the target DNS record, and then the application server deployed on the target MEC platform can be accessed according to the target DNS record, so that the application server can be switched in time; on the other hand, in the switching process of the application server, the terminal application and the application server deployed on the MEC platform do not need to be perceived, so that the terminal application and the application server deployed on the MEC platform do not need to be adapted and developed, and conditions can be created for large-scale application of the MEC. That is to say, based on the application server switching method, the application server can be switched in time in the scenario that the terminal is switched from the source MEC platform to the target MEC platform for access, and the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform do not need to be adapted and developed, thereby creating conditions for large-scale application of the MEC.

Optionally, if M is equal to 1, the application server switching method may be described as: a terminal receives a Domain Name System (DNS) refreshing message, wherein the DNS refreshing message carries a DNS record identifier and is used for indicating and refreshing a source DNS record corresponding to the DNS record identifier, the source DNS record comprises a corresponding relation between a domain name of an application server deployed on a source MEC platform and a corresponding source Internet Protocol (IP) address, and the source IP address is an IP address associated with the source MEC platform; and the terminal refreshes the source DNS record corresponding to the DNS record identifier according to the DNS refreshing message to obtain a target DNS record, wherein the target DNS record comprises the corresponding relation between the domain name of the application server deployed on the target MEC platform and the corresponding target IP address, and the target IP address is the IP address associated with the target MEC platform. The corresponding beneficial effects can refer to the beneficial effects of the application server switching method, and are not described herein again.

In a possible design, the terminal, according to the DNS refresh message, refreshes the source DNS record corresponding to the DNS record identifier to obtain the target DNS record, including: the terminal deletes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message; for each application server, which is also deployed on the target MEC platform and needs to be accessed by the terminal, of the M application servers, the terminal is processed in the following manner for the first application server: under the condition that a terminal needs to access the first application server, the terminal sends a DNS analysis request, wherein the DNS analysis request is used for requesting a target IP address corresponding to the domain name of the first application server; the terminal receives a target IP address corresponding to the domain name of the first application server, and stores the corresponding relation between the domain name of the first application server and the target IP address corresponding to the domain name of the first application server. Based on the scheme, after the MEC platform is switched, the terminal can delete the source DNS record corresponding to the DNS record identifier according to the DNS refresh message, so when the terminal determines that the corresponding application server needs to be accessed through a domain name corresponding to a certain deleted DNS record, the corresponding DNS record cannot be queried in the local cache, and therefore the DNS request is re-initiated, so that the source DNS record corresponding to the DNS record identifier can be refreshed in time to obtain the target DNS record.

In a possible design, the terminal, according to the DNS refresh message, refreshes the source DNS record corresponding to the DNS record identifier to obtain the target DNS record, including: according to the DNS refresh message, the terminal processes each application server that is also deployed on the target MEC platform among the M application servers and that the terminal needs to access, in the following manner for the first application server: under the condition that a terminal needs to access the first application server, the terminal sends a DNS analysis request, wherein the DNS analysis request is used for requesting a target IP address corresponding to the domain name of the first application server; the terminal receives a target IP address corresponding to the domain name of the first application server, and replaces a source IP address corresponding to the domain name of the first application server in a first DNS record with the target IP address corresponding to the domain name of the first application server to obtain a second DNS record, wherein the first DNS record is the corresponding relation between the domain name of the first application server and the source IP address corresponding to the domain name of the first application server; the second DNS record is a correspondence between the domain name of the first application server and the target IP address corresponding to the domain name of the first application server. Based on the scheme, after the MEC platform is switched, the terminal can also deploy the DNS request to each application server which is also deployed on the target MEC platform and needs to be accessed by the terminal again according to the DNS refresh message, so that the source DNS record corresponding to the DNS record identifier can be refreshed in time to obtain the target DNS record.

In one possible design, the terminal receives a DNS refresh message, including: and the terminal receives an application trigger request from the control equipment, wherein the application trigger request carries the DNS refresh message. Because the scheme can reuse the existing application trigger flow when the DNS refresh message is sent, the complexity of the implementation of the scheme is simplified, and the implementability of the scheme is increased.

In one possible design, the terminal receives a DNS refresh message, including: the terminal receives a DNS refresh message from the session management entity. The scheme does not need to limit the terminal to support the application triggering mechanism, so the application range of the scheme is expanded.

In a second aspect, an application server switching method is provided, which is applied in a scenario where a terminal switches from a source mobile edge computing MEC platform to a target MEC platform for access, and the method includes: the control equipment receives a switching notice from a session management entity, wherein the switching notice is used for indicating the terminal to have MEC platform switching; the control equipment acquires a Domain Name System (DNS) record identifier according to the switching notification; the control device sends a DNS refresh message to the terminal, wherein the DNS refresh message carries the DNS record identifier, the DNS refresh message is used for indicating a source DNS record corresponding to the DNS record identifier to be refreshed, the source DNS record comprises a corresponding relation between a domain name of each application server in M application servers deployed on the source MEC platform and a corresponding source Internet protocol IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer. For the corresponding beneficial effects, reference may be made to the description of the beneficial effects in the first aspect, which is not described herein again.

In one possible design, the controlling device sends the DNS refresh message to the terminal, including: and the control equipment sends an application trigger request to the terminal, wherein the application trigger request carries the DNS refresh message. Because the scheme can reuse the existing application trigger flow when the DNS refresh message is sent, the complexity of the implementation of the scheme is simplified, and the implementability of the scheme is increased.

In one possible design, before the control device receives the handover notification from the session management entity, the method further includes: the control device sends a subscription request to the session management entity, wherein the subscription request is used for requesting to subscribe the switching event of the MEC platform. By subscribing the switching event of the MEC platform, customized service can be realized, so that the control equipment is informed in time under the condition that the MEC platform is switched at the terminal, and the application server is switched in time through the control equipment.

In one possible design, the switching notification carries a DNS record identifier; the control device obtains the DNS record identifier according to the switching notification, including: the control device obtains the DNS record identifier from the switching notification. Therefore, the control device can quickly acquire the DNS record identification.

In one possible design, the switchover notification carries an identification of the source MEC platform; the control device obtains the DNS record identifier according to the switching notification, including: and the control equipment determines the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier. Therefore, the control equipment can locally acquire the DNS record identifier after receiving the switching notification, the signaling interaction with external equipment is reduced, and the signaling resource is saved.

In one possible design, before the control device determines the DNS record identifier, the method further includes: the control device determines that the DNS record identification is within the validity period. Therefore, invalid operation caused by acquiring the DNS record identification which is not in the validity period can be avoided.

In one possible design, the switchover notification carries an identification of the source MEC platform; the control device obtains the DNS record identifier according to the switching notification, including: and the control equipment queries the DNS record identifier from the warehouse functional entity according to the identifier of the source MEC platform. Therefore, the DNS record identifier can not be carried in the switching notification, and the control equipment can be ensured to be capable of acquiring the DNS record identifier under the condition that the DNS record identifier cannot be acquired locally.

In a third aspect, a method for switching an application server is provided, where the method is applied in a scenario where a terminal switches from a source mobile edge computing MEC platform to a target MEC platform for access, and the method includes: a session management entity acquires a Domain Name System (DNS) record identifier; a session management entity sends a DNS refresh message to the terminal, where the DNS refresh message carries the DNS record identifier, and the DNS refresh message is used to indicate to refresh a source DNS record corresponding to the DNS record identifier, where the source DNS record includes a correspondence between a domain name of each application server in M application servers deployed on the source MEC platform and a corresponding source internet protocol IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer. For the corresponding beneficial effects, reference may be made to the description of the beneficial effects in the first aspect, which is not described herein again.

In one possible design, the session management entity obtains the DNS record identifier, including: and the session management entity determines the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier. Therefore, the session management entity can obtain the DNS record identifier from the local, the signaling interaction with external equipment is reduced, and the signaling resource is saved.

In one possible design, before the session management entity determines the 3DNS record identifier, the method further includes: the session management entity determines that the DNS record identification is within the validity period. Therefore, invalid operation caused by acquiring the DNS record identification which is not in the validity period can be avoided.

In one possible design, the session management entity obtains the DNS record identifier, including: and the session management entity queries the DNS record identifier from the warehouse functional entity according to the identifier of the source MEC platform. Therefore, the session management entity can be ensured to be capable of acquiring the DNS record identifier under the condition that the DNS record identifier cannot be locally acquired.

In a fourth aspect, a method for switching an application server is provided, where the method includes: a terminal receives a Domain Name System (DNS) refreshing message, wherein the DNS refreshing message carries a DNS record identifier and is used for indicating to refresh a source DNS record corresponding to the DNS record identifier, and the source DNS record comprises a corresponding relation between a domain name of a source application server and a corresponding source Internet Protocol (IP) address; and the terminal refreshes the source DNS record corresponding to the DNS record identifier according to the DNS refreshing message to obtain a target DNS record, wherein the target DNS record comprises the corresponding relation between the domain name of the target application server and the corresponding target IP address, and the domain name of the source application server is the same as the domain name of the target application server.

In a possible design, the terminal refreshes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message, including: the terminal deletes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message; under the condition that the terminal needs to access the target application server, the terminal sends a DNS analysis request, wherein the DNS analysis request is used for requesting a target IP address corresponding to the domain name of the target application server; and the terminal receives the target IP address and stores the corresponding relation between the domain name of the target application server and the corresponding target IP address so as to obtain a target DNS record.

In a possible design, the terminal refreshes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message, including: under the condition that the terminal needs to access the target application server, the terminal sends a DNS analysis request, wherein the DNS analysis request is used for requesting a target IP address corresponding to the domain name of the target application server; and the terminal receives the target IP address and replaces the source IP address in the source DNS record with the target IP address corresponding to the domain name of the first application server to obtain a target DNS record.

For specific implementation of the terminal receiving the DNS refresh message, reference may be made to the relevant description in the first aspect, and details are not described here again.

The technical effects brought by any one of the design manners in the fourth aspect can be referred to the technical effects brought by different design manners in the first aspect, and are not described herein again.

In a fifth aspect, a method for switching an application server is provided, where the method includes: the control equipment receives a switching notice from a session management entity, wherein the switching notice is used for indicating the terminal to generate AS switching; the control equipment acquires a Domain Name System (DNS) record identifier according to the switching notification; the control device sends a DNS refresh message to the terminal, wherein the DNS refresh message carries the DNS record identifier, and the DNS refresh message is used for indicating to refresh a source DNS record corresponding to the DNS record identifier, and the source DNS record comprises a corresponding relation between a domain name of a source application server and a corresponding source Internet Protocol (IP) address.

In one possible design, the controlling device sends the DNS refresh message to the terminal, including: and the control equipment sends an application trigger request to the terminal, wherein the application trigger request carries the DNS refresh message.

In one possible design, before the control device receives the handover notification from the session management entity, the method further includes: the control device sends a subscription request to the session management entity, wherein the subscription request is used for requesting to subscribe the switching event of the MEC platform.

The specific implementation of the control device obtaining the DNS record identifier according to the switching notification may refer to the related description in the second aspect, and is not described herein again.

The technical effects brought by any one of the design manners in the fifth aspect can be referred to the technical effects brought by different design manners in the second aspect, and are not described herein again.

In a sixth aspect, a method for switching application servers is provided, where the method includes: a session management entity acquires a Domain Name System (DNS) record identifier; and the session management entity sends a DNS refresh message to the terminal, wherein the DNS refresh message carries the DNS record identifier, and the DNS refresh message is used for indicating to refresh a source DNS record corresponding to the DNS record identifier, and the source DNS record comprises a corresponding relation between a domain name of a source application server and a corresponding source Internet Protocol (IP) address.

For specific implementation of the session management entity obtaining the DNS record identifier, reference may be made to the related description in the third aspect, which is not described herein again.

The technical effects brought by any one of the design manners in the sixth aspect can be referred to the technical effects brought by different design manners in the third aspect, and are not described herein again.

In a seventh aspect, a terminal is provided, where the terminal has a function of implementing the method of the first or fourth aspect. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.

In an eighth aspect, there is provided a terminal comprising: a processor and a memory; the memory is configured to store computer executable instructions, and when the terminal runs, the processor executes the computer executable instructions stored in the memory, so as to enable the terminal to perform the application server switching method according to any one of the first aspect or the fourth aspect.

A ninth aspect provides a computer-readable storage medium having stored therein instructions, which, when run on a computer, cause the computer to perform the application server switching method of any one of the first or fourth aspects.

A tenth aspect provides a computer program product comprising instructions which, when run on a computer, enable the computer to perform the application server switching method of any one of the first or fourth aspects.

In an eleventh aspect, a chip system is provided, where the chip system includes a processor configured to enable a terminal to implement the functions recited in the foregoing aspects, for example, to refresh a source DNS record corresponding to a DNS record identifier according to a DNS refresh message. In one possible design, the system-on-chip further includes a memory for storing program instructions and data necessary for the terminal. The chip system may be constituted by a chip, or may include a chip and other discrete devices.

For technical effects brought by any one of the design manners in the seventh aspect to the eleventh aspect, reference may be made to technical effects brought by different design manners in the first aspect, and details are not described here.

In a twelfth aspect, there is provided a control apparatus having a function of implementing the method of the second or fifth aspect. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.

In a thirteenth aspect, there is provided a control apparatus comprising: a processor and a memory; the memory is configured to store computer-executable instructions, and when the control device is running, the processor executes the computer-executable instructions stored in the memory, so as to enable the control device to execute the application server switching method according to any one of the second aspect and the fifth aspect.

In a fourteenth aspect, a computer-readable storage medium is provided, which has instructions stored therein, and when the computer-readable storage medium runs on a computer, the computer is enabled to execute the application server switching method of any one of the second aspect or the fifth aspect.

In a fifteenth aspect, there is provided a computer program product containing instructions which, when run on a computer, enable the computer to perform the application server switching method of any one of the second or fifth aspects.

In a sixteenth aspect, a chip system is provided, where the chip system includes a processor, configured to support a control device to implement the functions recited in the foregoing aspects, for example, to obtain a DNS record identifier of a domain name system according to a handover notification. In one possible design, the system-on-chip further includes a memory for storing program instructions and data necessary for controlling the device. The chip system may be constituted by a chip, or may include a chip and other discrete devices.

For technical effects brought by any one of the design manners in the twelfth aspect to the sixteenth aspect, reference may be made to technical effects brought by different design manners in the second aspect, and details are not described herein.

A seventeenth aspect provides a session management entity having the functionality to implement the method of the third or sixth aspect. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.

In an eighteenth aspect, there is provided a session management entity, comprising: a processor and a memory; the memory is configured to store computer-executable instructions, and when the session management entity runs, the processor executes the computer-executable instructions stored in the memory, so that the session management entity executes the application server switching method according to any one of the third aspect and the sixth aspect.

A nineteenth aspect provides a computer-readable storage medium having instructions stored therein, which when run on a computer, cause the computer to perform the application server switching method of any one of the third or sixth aspects.

A twentieth aspect provides a computer program product containing instructions which, when run on a computer, causes the computer to perform the application server switching method of any one of the third or sixth aspects.

In a twenty-first aspect, a chip system is provided, where the chip system includes a processor for enabling a session management entity to implement the functions referred to in the foregoing aspects, such as obtaining a domain name system DNS record identifier. In one possible design, the system-on-chip further includes a memory for storing program instructions and data necessary for the session management entity. The chip system may be constituted by a chip, or may include a chip and other discrete devices.

For technical effects brought by any one of the design manners in the seventeenth aspect to the twenty-first aspect, reference may be made to technical effects brought by different design manners in the third aspect, and details are not described here.

In a twenty-second aspect, there is provided an application server switching system comprising a terminal and a control device as shown in the above-mentioned aspect; alternatively, the application server switching system comprises a terminal and a session management entity as described in the above aspect.

These and other aspects of the present application will be more readily apparent from the following description of the embodiments.

Drawings

Fig. 1 is a schematic diagram of a switching process of a conventional MEC platform;

FIG. 2 is a flow chart illustrating a conventional application triggering mechanism;

fig. 3 is a schematic architecture diagram of an application server switching system according to an embodiment of the present application;

fig. 4 is a schematic view of an application architecture of an application server switching system in 5G according to an embodiment of the present application;

fig. 5 is a schematic hardware structure diagram of a communication device according to an embodiment of the present application;

fig. 6 is a first flowchart illustrating an application server switching method according to an embodiment of the present application;

fig. 7 is a second flowchart illustrating an application server switching method according to an embodiment of the present application;

fig. 8 is a third schematic flowchart of a method for switching an application server according to an embodiment of the present application;

FIG. 9 is a schematic structural diagram of an apparatus according to an embodiment of the present disclosure;

fig. 10 is a schematic structural diagram of a control device provided in an embodiment of the present application;

fig. 11 is a schematic structural diagram of a session management entity according to an embodiment of the present application.

Detailed Description

To facilitate understanding of the technical solutions of the embodiments of the present application, a brief description of the related art of the present application is first given as follows.

An MEC platform:

the MEC platform is a platform formed by deploying the functions of service processing and resource scheduling of the application server and the MBB core network part to the network edge close to the access side together. Generally, a User Plane Function (UPF) entity, various application servers and DNS Proxy (DNSP) entities, etc. may be deployed on the MEC platform, which is not specifically limited in this embodiment of the present invention.

Optionally, the MEC platform in the embodiment of the present application may also be referred to as an MEC system or another, which is not specifically limited in the embodiment of the present application.

The terminal application:

the terminal application refers to a software product installed on the terminal and used for accessing the service provided by the application server, and may also be referred to as an application client on the terminal, for example, a wechat client on the terminal or a browser on the terminal, and may be used for accessing the service provided by the wechat server, which is described herein in a unified manner and will not be described in detail below.

An application server:

the application server in the embodiment of the present application refers to a carrier capable of providing a corresponding service. For example, the wechat server may be a carrier capable of providing wechat services.

The carrier in this embodiment of the present application may be a virtual device or an entity device, which is not specifically limited in this embodiment of the present application. The virtual device may be, for example, a virtual machine or a container, and this is not particularly limited in this embodiment of the present application.

Edge application server and central application server:

the edge application server refers to an application server deployed on the MEC platform, and the central application server is relative to the edge server, and may interact with the edge application server, for example, may issue control information or synchronization data to the edge application server, so the edge application server generally has all functions or part of functions of the central application server, which is not specifically limited in this embodiment of the present invention. In addition, because the edge application server is deployed at the edge of the network close to the access network side, that is, the deployment position is low, better services, such as lower delay, higher rate, and the like, can be provided for the user.

It should be noted that, in the following description in the embodiments of the present application, an application server deployed on an MEC platform may be described as an edge application server, or may be directly described as an application server deployed on an MEC platform, which is not specifically limited in the embodiments of the present application. The description is unified here, and will not be repeated below.

DNS record:

a terminal accesses an application server usually through a domain name, and when accessing through the domain name, an IP address of a corresponding application server needs to be obtained through a DNS resolution request, where a mapping relationship between a domain name and an IP address is a DNS record.

DNS caching:

the terminal usually caches the DNS record for a certain time after obtaining the DNS record, and the terminal can directly use the cached DNS record when accessing the domain name again in the time without initiating a new DNS analysis request to obtain the IP address of the corresponding application server.

Address assignment of edge application server:

the IP address of the edge application server is usually allocated by the MEC platform when the edge application server is deployed, but may be uniformly allocated by other address allocation devices. The IP address of the edge application server may be a private network IP address or a public network IP address, which is not specifically limited in this embodiment of the present application.

In one possible implementation, the IP address of the application server deployed on each MEC platform may be in one or more IP address segments, and the IP addresses of the application servers deployed on different MEC platforms may be different. For example, the deployment system may allocate IP address segments 1.1.0.1-1.1.255.255 for application servers on the MEC platform 1 and IP address segments 2.2.0.1-2.2.255.255 for application servers on the MEC platform 2. Furthermore, when the MEC platform 1 deploys the application server on the MEC platform 1, the IP address of the application server corresponding to app.com may be allocated to be 1.1.1.2; when the MEC platform 2 deploys the application servers on the MEC platform 2, the IP address of the application server corresponding to app.com may be allocated to 2.2.1.2.

DNS proxy on MEC platform:

each MEC platform may be deployed with a DNSP entity, each application server, when deployed to the MEC platform, may be assigned with a private domain name by the deployment system, where the private domain name is determined by the real domain name of the application server and an identifier of the MEC platform on which the application server is deployed, and the format is usually the real domain name +. MECID > of the application server, for example, the real domain name of an application server is app.com, and when deployed to the MEC platform 1, may be assigned with a private domain name app.com.mec1, and the DNSP entity may store a mapping relationship between app.com and app.com.mec1, and a mapping relationship between app.com.mec1 and an IP address of the application server deployed to the MEC platform 1. When the terminal initiates a DNS resolution request of app.com, the UPF entity on the MEC platform 1 forwards the DNS resolution request to the DNSP entity, and the DNSP entity finds its private domain name app.com.mec1 through app.com, finds the IP address of the application server deployed to the MEC platform 1 through app.com.mec1, and sends the IP address to the terminal through a DNS resolution response.

It should be noted that, in this embodiment of the present application, the identifier of the MEC platform is used to uniquely identify one MEC platform, and may be, for example, location information of a UPF entity deployed on the MEC platform or a Data Network Access Identifier (DNAI), and the like, which is not limited in this embodiment of the present application. The description is unified here and will not be repeated below.

It should be noted that in this embodiment of the application, when a terminal accesses a certain application server, the terminal generally accesses through a domain name of the application server, where the domain name of the application server refers to a real domain name of the application server, and the description is not repeated herein in a unified manner.

And switching the MEC platform:

the handover of the MEC platform may be caused by the handover of the access device, or may be caused by other reasons, which is not specifically limited in this embodiment of the present application. Here, taking an example that the handover of the MEC platform is caused by the handover of the access device, the handover flow of the MEC platform may be as shown in fig. 1:

s101, configuring a corresponding relation between the access equipment and the mark of the MEC platform in advance on a Session Management Function (SMF) entity in a core network. The correspondence is used to characterize which MEC platform provides services when accessed through which access device.

S102, the terminal triggers the access device to be switched due to the reason of moving and the like, for example, the access device is switched from the source access device to the target access device to be accessed.

S103, the target access equipment sends a path switching request (path switching request) to the AMF entity in the core network, so that the AMF entity receives the path switching request from the target access equipment.

S104, the AMF entity sends a bearer modification request (modify bearer request) to the SMF entity in the core network, so that the SMF entity receives the bearer modification request from the AMF entity.

S105, the SMF entity determines that the access equipment is switched, determines whether the MEC platform is required to be switched according to the corresponding relation between the access equipment and the marks of the MEC platform, and sends a session establishment request (create session request) to a target UPF entity deployed on the target MEC platform if the MEC platform is required to be switched so that the target UPF entity receives the session establishment request from the SMF entity.

S106, the target UPF entity sends a session establishment response (create session response) to the SMF entity, so that the SMF entity receives the session establishment response from the target UPF entity.

S107, the SMF entity sends a bearer modification response (modify bearer response) to the AMF entity, so that the AMF entity receives the bearer modification response from the SMF entity.

S108, the AMF entity sends a path switch response (path switch response) to the target access equipment, so that the target access equipment receives the path switch response from the AMF entity.

S109, the SMF entity sends a session deletion request (deletion request) to the source UPF entity deployed on the source MEC platform, so that the source UPF entity receives the session deletion request from the SMF entity.

S110, the source UPF entity sends a session deletion response (delete session response) to the SMF entity, so that the SMF entity receives the session deletion response from the source UPF entity.

So far, the basic flow of MEC switching ends. The specific implementation of steps S101 to S110 may refer to the switching process of the existing MEC platform, which is not described herein again.

It should be noted that, because the deployment position of the MEC platform is low, and the coverage area of each MEC platform is limited, the switching of the MEC platform is easily triggered when the terminal moves, and the description is unified here and will not be repeated below.

Application trigger (application trigger) mechanism:

an application triggering mechanism provides a method for controlling a terminal-oriented active push message by an application server through a core network, and the mechanism is described in detail in 3rd generation partnership project (3 GPP) 23.5014.4.5 and 23.5025.2.6.1. The main flow is shown in fig. 2, and comprises the following steps:

s201, an application server sends an application trigger request (application trigger request) to a network outside function (NEF) entity, so that the NEF entity receives the application trigger request from the application server.

The application trigger request may include a terminal identifier, a requester identifier, a validity period of the message, an identifier of a terminal application, a trigger load (trigger load), and the like, where the terminal identifier may be, for example, an International Mobile Subscriber Identity (IMSI) or an IP address of the terminal, and is used to indicate to which terminal the message is pushed; the requester identifier may be, for example, an IP address or a name of the application server, and is used to indicate which application server the message originates, where the requester identifier is generally an identifier allocated by the operator or negotiated by both the operator and the operator after the application server signs a contract with the operator, and may be used to authenticate, quota control, or charge the message sender; the validity period of the message is used for indicating how long the message is valid, and if the message is failed to be sent and is still in the validity period, the core network is required to retransmit the message; the identifier of the terminal application may be, for example, a digital identifier or a domain name, and is also a globally unique identifier that is allocated by an operator or negotiated by both parties after the application server signs a contract with the operator, and is used to indicate to which terminal application on the terminal the message needs to be sent; the trigger load is content that needs to be processed by the terminal application, and reference may be made to the existing scheme, which is not described herein again.

S202, the NEF entity acquires relevant information of the terminal from Unified Data Management (UDM) according to the terminal identification carried in the application trigger request.

The related information of the terminal may be, for example, core network element information for providing a service for the terminal, such as which access and mobility management function (AMF) provides the service for the terminal.

S203, the NEF entity sends the application trigger request to the AMF entity serving the terminal, so that the AMF entity receives the application trigger request from the NEF entity.

S204, the AMF entity sends an application trigger request to the terminal, so that the terminal receives the application trigger request from the AMF entity.

S205, the terminal sends an application trigger response (application trigger response) to the AMF entity, so that the AMF entity receives the application trigger response from the terminal. Wherein the application trigger response is used for indicating that the terminal has successfully received the application trigger request.

S206, the AMF entity sends the application trigger response to the NEF entity, so that the NEF entity receives the application trigger response from the AMF entity.

S207, the NEF entity sends the application trigger response to the application server, so that the application server receives the application trigger response from the NEF entity.

At this point, the basic flow of the application triggering mechanism ends. The specific implementation of steps S201 to S207 may refer to the existing application triggering mechanism process, which is not described herein again.

It should be noted that the terminal that must support the application triggering mechanism can use the application triggering procedure. How to enable the terminal to support the application triggering mechanism may have various implementation manners, for example, after receiving a non-access stratum (NAS) message, the baseband chip of the terminal recognizes that the message is an application triggering request, and may send the application triggering request to the terminal OS for processing. Furthermore, a service provided by the terminal OS may process the application trigger request, where the service provided by the terminal OS is a function or a function module provided by the operating system, and implements some specific functions, such as device control, message notification function, and the like, which are described in a unified manner and are not described in detail below. Or after receiving the application trigger request, the terminal OS may send the application trigger request to a specific terminal application for processing according to the identifier of the terminal application carried in the application trigger request, which is not specifically limited in this embodiment of the present application. Since the terminal application for processing the application trigger request is a special application, the identifier of the corresponding terminal application may be a special identifier allocated by an operator, such as "0", which is described herein in a unified manner and is not described in detail below.

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. Where in the description of the present application, "/" indicates an OR meaning, for example, A/B may indicate A or B; "and/or" herein is merely an association describing an associated object, and means that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. Also, in the description of the present application, "a plurality" means two or more than two unless otherwise specified. In addition, in order to facilitate clear description of technical solutions of the embodiments of the present application, in the embodiments of the present application, terms such as "first" and "second" are used to distinguish the same items or similar items having substantially the same functions and actions. Those skilled in the art will appreciate that the terms "first," "second," etc. do not denote any order or quantity, nor do the terms "first," "second," etc. denote any order or importance.

The network architecture and the service scenario described in the embodiment of the present application are for more clearly illustrating the technical solution of the embodiment of the present application, and do not form a limitation on the technical solution provided in the embodiment of the present application, and as a person of ordinary skill in the art knows that along with the evolution of the network architecture and the appearance of a new service scenario, the technical solution provided in the embodiment of the present application is also applicable to similar technical problems.

As shown in fig. 3, for an application server switching system 30 provided in the embodiment of the present application, the application server switching system 30 includes a terminal, one or more application servers deployed in a source MEC platform, one or more application servers deployed in a target MEC platform, and a session management entity deployed in a core network. The one or more application servers deployed in the source MEC platform may include, for example, source application server 1, … …, source application server k, and application server p; the one or more application servers deployed in the target MEC platform may include, for example, target application server 1, … …, target application server k, and application server q, etc., where p, q, k are positive numbers.

It should be noted that the numbers behind the application server or the source application server or the target application server in fig. 3 are used to distinguish the application servers providing different services, and if the numbers are the same, the same service may be considered to be provided. For example, the source application server 1 and the target application server 1 provide the same service, and the source application server k and the target application server k provide the same service. Of course, in the embodiment of the present application, some application servers may also be deployed only on one of the source MEC platform and the target MEC platform, and are not deployed on both the source MEC platform and the target MEC platform. For example, as shown in fig. 3, an application server p is deployed on a source MEC platform, and a corresponding application server is not deployed on a target MEC platform; the application server q is deployed on the target MEC platform, and a corresponding application server is not deployed on the source MEC platform, which is not specifically limited in this embodiment of the present application.

Optionally, in a possible implementation manner, in a scenario where the terminal is switched to access from the source MEC platform to the target MEC platform, the session management entity is configured to obtain a DNS record identifier and send a DNS refresh message to the terminal, where the DNS refresh message carries the DNS record identifier and is used to instruct to refresh the source DNS record corresponding to the DNS record identifier. The source DNS record includes a correspondence between a domain name of each of M application servers deployed on the source MEC platform and a corresponding source IP address, where the source IP address is an IP address associated with the source MEC platform, and M is a positive integer.

And the terminal is used for receiving the DNS refresh message from the session management entity and refreshing the source DNS record corresponding to the DNS record identifier according to the DNS refresh message so as to obtain the target DNS record. The target DNS record includes a correspondence between a domain name of each application server in the M application servers, which is also deployed on the target MEC platform, and a corresponding target IP address, where the target IP address is an IP address associated with the target MEC platform.

It should be noted that, in the embodiment of the present application, application servers providing the same function or service are deployed on different MEC platforms, and may have different IP addresses. When an application server X is deployed on any MEC platform Y, we call application server X associated with the MEC platform Y, and the IP address of the application server X is the IP address associated with the MEC platform Y. For example, the source IP address is an IP address associated with the source MEC platform, specifically, the source IP address is an IP address of an application server deployed on the source MEC platform; the target IP address is an IP address associated with the target MEC platform, specifically, the target IP address is an IP address of an application server deployed on the target MEC platform, which is described in a unified manner herein and is not described in detail below.

Alternatively, optionally, in another possible implementation manner, as shown in fig. 3, the application switching system 30 provided in the embodiment of the present application may further include a control device. The control device is used for receiving a switching notification from the session management entity, wherein the switching notification is used for indicating the terminal to have MEC platform switching.

And the control device is further configured to obtain a DNS record identifier according to the switching notification, and send a DNS refresh message to the terminal, where the DNS refresh message carries the DNS record identifier and is used to instruct to refresh a source DNS record corresponding to the DNS record identifier. The source DNS record includes a correspondence between a domain name of each of M application servers deployed on the source MEC platform and a corresponding source IP address, where the source IP address is an IP address associated with the source MEC platform, and M is a positive integer.

And the terminal is used for receiving the DNS refresh message from the control equipment and refreshing the source DNS record corresponding to the DNS record identifier according to the DNS refresh message so as to obtain the target DNS record. The target DNS record includes a correspondence between a domain name of an application server, which is also deployed on the target MEC platform, among the M application servers and a corresponding target IP address, where the target IP address is an IP address associated with the target MEC platform.

Optionally, the control device in this embodiment of the present application may be an application server or an Application Function (AF) entity, and this is not specifically limited in this embodiment of the present application. The description is unified here and will not be repeated below.

Optionally, in this embodiment of the application, the M application servers deployed on the source MEC platform may be part or all of the application servers deployed on the source MEC platform, and this is not specifically limited in this embodiment of the application. The description is unified here and will not be repeated below.

Optionally, in this embodiment of the application, for an application server deployed on a source MEC platform and an application server also deployed on a target MEC platform, after a terminal is switched over to an MEC platform, a part or all of the application servers may be switched over. For example, after the MEC platform switching occurs at the terminal, the source application server k deployed on the source MEC platform may be switched, and the source application server 1 deployed on the source MEC platform may not be switched; or, both the source application server k and the source application server 1 deployed on the source MEC platform are switched, which is not specifically limited in this embodiment of the present application. The description is unified here and will not be repeated below. In this embodiment, the switching of the application server refers to that the terminal can quickly switch the accessed object from the source application server deployed on the source MEC platform to the target application server deployed on the target MEC platform and providing the same service, which is described in a unified manner herein and is not described in detail below.

Optionally, in this embodiment of the present application, the source IP address and the target IP address may be private network IP addresses or public network IP addresses, which is not specifically limited in this embodiment of the present application. The description is unified here and will not be repeated below.

Optionally, each device in the application server switching system provided in the embodiment of the present application may communicate directly with each other, or communicate through forwarding of other devices, which is not specifically limited in the embodiment of the present application.

In the application server switching system provided by the embodiment of the application server switching method and system, when the terminal is switched to access from the source MEC platform to the target MEC platform, the control device or the session management entity can send the DNS refresh message to the terminal, so that the terminal can refresh the source DNS record corresponding to the DNS record identifier according to the DNS refresh message to obtain the target DNS record. On one hand, after the MEC platform is switched, the source DNS record corresponding to the DNS record identifier can be refreshed in time to obtain the target DNS record, and then the application server deployed on the target MEC platform can be accessed according to the target DNS record, so that the application server can be switched in time; on the other hand, in the switching process of the application server, the terminal application and the application server deployed on the MEC platform do not need to be perceived, so that the terminal application and the application server deployed on the MEC platform do not need to be adapted and developed, and conditions can be created for large-scale application of the MEC. That is to say, based on the application server switching system, in a scenario where the terminal is switched from the source MEC platform to the target MEC platform for access, the application server can be switched in time, and the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform do not need to be adapted and developed, which creates conditions for large-scale application of the MEC.

Alternatively, the application switching system shown in fig. 3 may be applied to a 5G network and other networks in the future, and this is not particularly limited in this embodiment of the present application.

Taking the application switching system shown in fig. 3 applied to a 5G network as an example, as shown in fig. 4, the session management entity in fig. 3 may be specifically a Session Management Function (SMF) entity. In addition, as shown in fig. 4, the core network may further include an access and mobility management function (AMF) entity, an NEF entity, a network function repository (NRF) entity, and the like; the source MEC platform may further include a source UPF entity, a first DNSP entity, and the like, and the target MEC platform may further include a target UPF entity, a second DNSP entity, and the like, which is not specifically limited in this embodiment of the present application.

Before the MEC platform switching of the terminal occurs, the terminal is accessed to a source MEC platform through first access equipment; after the MEC platform switching of the terminal occurs, the terminal is accessed to a target MEC platform through second access equipment; the first access equipment communicates with a source UPF entity through a Next generation network (N) interface 3 (N3 for short); the second access equipment communicates with the target UPF entity through an N interface 3 (N3 for short); the first access equipment and the second access equipment are communicated with the AMF entity through an N interface 2 (N2 for short); the AMF entity communicates with the SMF entity via an N interface 11 (abbreviated N11), and the SMF entity may communicate with the NRF entity. Application servers deployed on the source MEC platform (such as application server q, source application server 1, … …, source application server k) and application servers deployed on the target MEC platform (such as application server q, target application server 1, … …, target application server k) may communicate through the NEF entity and the NRF entity; the SMF entity may communicate with the control device through the NEF entity, and the NRF entity may communicate with the control device through the NEF entity.

It should be noted that, the embodiment shown in fig. 4 is exemplified by the control device, the application server deployed on the source MEC platform, and the NEF entity through which the application server deployed on the target MEC platform communicates with the NRF entity being the same NEF entity, but the NEF entity may be deployed in a distributed manner. For example, the application server deployed on the source MEC platform may communicate with the NRF entity through the NEF entity deployed on the source MEC platform, and the application server deployed on the target MEC platform may communicate with the NRF entity through the NEF entity deployed on the target MEC platform, which is described in a unified manner and will not be described in detail below. Optionally, in the embodiment shown in fig. 4, the example is described as that the terminal is accessed through different access devices before the MEC platform of the terminal is switched and after the MEC platform of the terminal is switched, and of course, the terminal may also be accessed through the same access device before the MEC platform of the terminal is switched and after the MEC platform of the terminal is switched, which is not specifically limited in the embodiment of the present application.

It should be noted that the interface name between each network element in fig. 4 is only an example, and the interface name may be other names in a specific implementation, which is not specifically limited in this embodiment of the present application.

It should be noted that the access device, SMF entity, UPF entity, AMF entity, NEF entity, NRF entity, etc. in fig. 4 are only names, and the names do not limit the device itself. In the 5G network and other networks in the future, the network elements or entities corresponding to the access device, the SMF entity, the UPF entity, the AMF entity, the NEF entity, and the NRF entity may also be other names, which is not specifically limited in this embodiment of the present application.

Optionally, the terminal (terminal) referred to in the embodiments of the present application may include various handheld devices with wireless communication functions, vehicle-mounted devices, wearable devices, computing devices, or other processing devices connected to a wireless modem; subscriber units (subscriber units), cellular phones (cellular phones), smart phones (smart phones), wireless data cards, Personal Digital Assistants (PDAs), tablet computers, wireless modems (modems), handheld devices (dhhandles), laptop computers (laptops), cordless phones (cordsets) or Wireless Local Loop (WLL) stations, Machine Type Communication (MTC) terminals, User Equipment (UE), Mobile Stations (MSs), terminal devices (terminal devices), and the like may also be included. For convenience of description, the above-mentioned devices are collectively referred to as a terminal in this application.

Optionally, the access device referred to in this embodiment refers to a device accessing a core network, and may be, for example, a base station, a broadband network service gateway (BNG), an aggregation switch, a non-third generation partnership project (3rd generation partnership project, 3GPP) access device, and the like. The base stations may include various forms of base stations, such as: macro base stations, micro base stations (also referred to as small stations), relay stations, access points, etc.

Optionally, the terminal, the session management entity, or the control device in fig. 3 may be implemented by one entity device, may also be implemented by multiple entity devices together, and may also be a logic function module in one entity device, which is not specifically limited in this embodiment of the present application.

For example, the terminal, the session management entity or the control device in fig. 3 may be implemented by the communication device in fig. 5. Fig. 5 is a schematic diagram illustrating a hardware structure of a communication device according to an embodiment of the present application. The communication device 500 includes at least one processor 501, communication lines 502, memory 503, and at least one communication interface 504.

The processor 501 may be a general-purpose Central Processing Unit (CPU), a microprocessor, an application-specific integrated circuit (ASIC), or one or more ics for controlling the execution of programs in accordance with the present disclosure.

The communication link 502 may include a path for transmitting information between the aforementioned components.

The communication interface 504 may be any device, such as a transceiver, for communicating with other devices or communication networks, such as an ethernet, a Radio Access Network (RAN), a Wireless Local Area Network (WLAN), etc.

The memory 503 may be, but is not limited to, a read-only memory (ROM) or other type of static storage device that can store static information and instructions, a Random Access Memory (RAM) or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disc, laser disc, optical disc, digital versatile disc, blu-ray disc, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory may be separate and coupled to the processor via a communication line 502. The memory may also be integral to the processor.

The memory 503 is used for storing computer-executable instructions for executing the present application, and is controlled by the processor 501 to execute. The processor 501 is configured to execute computer-executable instructions stored in the memory 503, so as to implement the application server switching method provided by the following embodiments of the present application.

Optionally, the computer-executable instructions in the embodiments of the present application may also be referred to as application program codes, which are not specifically limited in the embodiments of the present application.

In particular implementations, processor 501 may include one or more CPUs such as CPU0 and CPU1 in fig. 5 as an example.

In particular implementations, communication device 500 may include multiple processors, such as processor 501 and processor 508 in fig. 5, for example, as an example. Each of these processors may be a single-core (single-CPU) processor or a multi-core (multi-CPU) processor. A processor herein may refer to one or more devices, circuits, and/or processing cores for processing data (e.g., computer program instructions).

In particular implementations, communication device 500 may also include an output device 505 and an input device 506, as one embodiment. An output device 505, which is in communication with the processor 501, may display information in a variety of ways. For example, the output device 505 may be a Liquid Crystal Display (LCD), a Light Emitting Diode (LED) display device, a Cathode Ray Tube (CRT) display device, a projector (projector), or the like. The input device 506 is in communication with the processor 501 and may receive user input in a variety of ways. For example, the input device 506 may be a mouse, a keyboard, a touch screen device, or a sensing device, among others.

The communication device 500 may be a general purpose device or a special purpose device. In a specific implementation, the communication device 500 may be a desktop, a laptop, a web server, a Personal Digital Assistant (PDA), a mobile phone, a tablet, a wireless terminal device, an embedded device, or a device with a similar structure as in fig. 5. The embodiment of the present application does not limit the type of the communication device 500.

The application server switching method provided in the embodiment of the present application will be specifically described below with reference to fig. 1 to 5.

It should be noted that, a name of a message between network elements in the following embodiments of the present application is only an example, and other names may also be used in a specific implementation, and this is not specifically limited in this embodiment of the present application.

It should be noted that fig. 6 to fig. 8 corresponding to the following embodiments of the present application only exemplarily show network elements required for relevant description, and network elements not involved in the description, such as a source access device, a source UPF entity and a first DNSP entity disposed on a source MEC platform, are not shown, and are collectively described herein and will not be described again below.

Taking the application architecture of the application server switching system shown in fig. 4 in the 5G network as an example, as shown in fig. 6, a method for switching an application server provided in the embodiment of the present application includes the following steps:

s601, configuring information related to the application server on the SMF entity.

Optionally, in this embodiment of the present application, the information related to the application server may include domain names of the application servers deployed on the source MEC platform and the target MEC platform, or IP addresses or IP address fields of the application servers deployed on the source MEC platform and the target MEC platform, and this is not specifically limited in this embodiment of the present application.

For example, the information related to the application server may be, for example, that the IP address field of the application server deployed on the source MEC platform is 1.1.1.1 to 1.1.255.255, and the IP address field of the application server deployed on the target MEC platform is 2.2.1.1 to 2.2.255.255.

Optionally, in this embodiment of the application, the information related to the application server may be automatically configured by an MEC application management network element (responsible for deployment and management of the application server on the MEC), or may be manually configured by an operation and maintenance person, which is not specifically limited in this embodiment of the application.

Optionally, the MEC application management network element in the embodiment of the present application may be, for example, the control device in fig. 4 or an independent MEC application deployment and management functional entity, which is not specifically limited in the embodiment of the present application.

It should be noted that step S601 in the embodiment of the present application is an optional step, that is, step S601 may not be included in the embodiment of the present application, which is described herein in a unified manner and is not described again below.

S602, after deploying the application server a on the source MEC platform, the application server a deployed on the source MEC platform registers information such as a domain name of the application server a and a corresponding IP address to the NRF entity, for example, the information may be appa.com.mec11.1.1.2, where appa.com is a real domain name of the application server a; MEC1 is the identification of the source MEC platform; 1.1.1.2 is the IP address of application Server A deployed on the Source MEC platform.

Optionally, the application server a in step S602 may be any one application server deployed on the source MEC platform, such as the source application server 1 in fig. 4; alternatively, source application server k in fig. 4; alternatively, the application server p in fig. 4, etc., are not particularly limited in this embodiment of the present application.

Optionally, as shown in fig. 6, when the application server a deployed on the source MEC platform registers information such as a domain name and a corresponding IP address of the application server a with the NRF entity, forwarding through the NEF entity is required, which is not specifically limited in this embodiment of the present application.

Optionally, each application server deployed on the source MEC platform may be executed according to the method of step S602, which is not described in detail herein.

S603, after deploying the application server B on the target MEC platform, the application server B deployed on the target MEC platform registers information such as a domain name of the application server B and a corresponding IP address to the NRF entity, for example, the information may be appb.com.mec 22.2.1.2, where appb.com is a real domain name of the application server B; MEC2 is the identification of the target MEC platform; 2.2.1.2 is the IP address of application server B deployed on the target MEC platform.

Optionally, the application server B in step S603 may be any one application server deployed on the target MEC platform, for example, may be the target application server 1 in fig. 4; alternatively, target application server k in fig. 4; alternatively, the application server q in fig. 4, etc., are not particularly limited in this embodiment of the present application.

Optionally, as shown in fig. 6, when the application server B deployed on the target MEC platform registers information such as a domain name and a corresponding IP address of the application server B with the NRF entity, forwarding through the NEF entity is required, which is not specifically limited in this embodiment of the present application.

Optionally, each application server deployed on the target MEC platform may be executed according to the method of step S603, and details are not repeated here.

Optionally, the application server a in step S602 and the application server B in step S603 may be the same application server or may be different application servers, which is not specifically limited in this embodiment of the application.

The specific implementation of the registration in step S602 and step S603 may refer to an existing implementation manner, which is not described herein again.

S604, the control device sends a subscription request to an SMF entity deployed in the core network, so that the SMF entity receives the subscription request from the control device. The subscription requesting application requests a subscription to a handover event of the MEC platform.

Optionally, in this embodiment of the application, the subscription request may carry an identifier of the MEC platform, that is, the subscription may be performed according to the identifier of the MEC platform. For example, the subscription request may carry an identifier of the MEC platform a, so that if any terminal switches from the MEC platform a to another MEC platform for access, or switches from another MEC platform to the MEC platform a for access, the SMF entity may be triggered to send a switching notification to the control device; or, the subscription request may carry an identifier of the MEC platform a and an identifier of the MEC platform B, so that if any terminal switches from the MEC platform a to the MEC platform B for access, or switches from the MEC platform B to the MEC platform a for access, the SMF entity may be triggered to send a switching notification to the control device. The mark of the MEC platform is carried in the subscription request, so that the customized service of the MEC platform corresponding to the mark of the MEC platform can be realized, and the timely switching of the application server can be realized when the MEC platform switched is included in the MEC platform.

Or, optionally, in this embodiment of the application, the subscription request may carry a terminal identifier, that is, the subscription may be performed according to the terminal identifier. For example, the subscription request may carry a terminal a identifier, so that if the terminal a is switched from any MEC platform to another MEC platform for access, the SMF entity may be triggered to send a switching notification to the control device. By carrying the terminal identification in the subscription request, the customized service of the terminal corresponding to the terminal identification can be realized, so that the timely switching of the application server can be realized when the terminal switched by the MEC platform is the terminal.

Or, optionally, in this embodiment of the present application, the terminal identifier and the identifier of the MEC platform may also be simultaneously carried, that is, the subscription may be performed according to the identifier of the MEC platform and the terminal identifier. For example, the subscription request may carry the identifier of the terminal a and the identifier of the MEC platform a, so that if the terminal a is switched from the MEC platform a to another MEC platform for access, or from another MEC platform to the MEC platform a for access, the SMF entity may be triggered to send a switching notification to the control device; or, the subscription request may carry the identifier of the terminal a, the identifier of the MEC platform a, and the identifier of the MEC platform B, so that if the terminal a is switched from the MEC platform a to the MEC platform B for access, or from the MEC platform B to the MEC platform a for access, the SMF entity may be triggered to send the switching notification to the control device. Through carrying the terminal identification and the identification of the MEC platform in the subscription request, the customized service of the terminal corresponding to the terminal identification on the MEC platform corresponding to the identification of the MEC platform can be realized, so that the terminal switched by the MEC platform can be the terminal, and the application server can be switched in time when the MEC platform is included in the MEC platform switched by the MEC platform.

Optionally, in this embodiment of the present application, the identifier of the MEC platform may be any information that can identify the MEC platform, for example, the identifier may be a globally unique MEC Identifier (ID) or a Data Network Access Identifier (DNAI) of a network where the MEC platform is located, and this is not specifically limited in this embodiment of the present application.

The description of the terminal identifier may refer to the embodiment shown in fig. 2, and is not repeated here.

Optionally, as shown in fig. 6, sending, by the control device, the subscription request to the SMF entity needs to be forwarded by the NEF entity, which is not specifically limited in this embodiment of the present application.

And S605, the terminal is switched from the source MEC platform to the target MEC platform for access.

The specific implementation of step S605 may refer to the embodiment shown in fig. 1, and is not described herein again.

Assuming that the subscription request in step S604 carries at least one of the terminal identifier, the identifier of the source MEC platform, or the identifier of the target MEC platform, the application switching method provided in the embodiment of the present application further includes the following steps:

s606, the SMF entity sends a handover notification to the control device, so that the control device receives the handover notification from the SMF entity. The switching notification is used for indicating the terminal to switch the MEC platform.

In the embodiment of the application, the switching notification carries a terminal identifier, and the terminal identifier is used for indicating a terminal where the MEC platform is switched.

Optionally, in this embodiment of the application, the switching notification may further carry an identifier of the source MEC platform, where the identifier of the source MEC platform is used to subsequently obtain the DNS record identifier, and specific reference may be made to the description of the subsequent embodiment, which is not described herein again.

Optionally, in this embodiment of the application, if the SMF entity is configured with an IP address or an IP address field of the application server deployed on the source MEC platform, or a domain name of the application server deployed on the source MEC platform, etc. in step S601, the switching notification at this time may also carry a DNS record identifier, which is not specifically limited in this embodiment of the application.

It should be noted that, in the embodiment of the present application, a DNS record identifier is an identifier corresponding to a source DNS record, where the source DNS record includes a correspondence between a domain name of each application server in M application servers deployed on a source MEC platform and a corresponding source IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer, which is described herein in a unified manner and is not described in detail below.

Optionally, the DNS record identifier in this embodiment of the present application may include, for example, domain names of M application servers deployed on the source MEC platform, or at least one of IP addresses or IP address sections of the M application servers deployed on the source MEC platform, which is not specifically limited in this embodiment of the present application.

Optionally, as shown in fig. 6, sending, by the SMF entity, the handover notification to the control device needs to be forwarded by the NEF entity, which is not specifically limited in this embodiment of the present application.

It should be noted that step S604 in the embodiment of the present application is an optional step, that is, step S604 may not be included in the embodiment of the present application, and step S606 is directly executed after the terminal is switched to access from the source MEC platform to the target MEC platform (step S605), which is not specifically limited in the embodiment of the present application.

S607, the control device obtains the DNS record identifier according to the switching notice.

Optionally, in a possible implementation manner, the DNS record identifier is carried in the handover notification in step S606, and then the control device obtains the DNS record identifier according to the handover notification at this time, which may specifically include: the control device obtains the DNS record identifier from the handover notification.

Or, optionally, in a possible implementation manner, assuming that the DNS record identifier is not carried in the switching notification in step S606 but carries an identifier of the MEC platform, at this time, the control device obtains the DNS record identifier according to the switching notification, which may specifically include: and the control equipment determines the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier.

For example, if the control device itself is responsible for deployment and management of the application server on the MEC platform, after the MEC platform is deployed, the control device may store the correspondence between the identifier of the source MEC platform and the DNS record identifier. In this way, after receiving the switching notification carrying the identifier of the source MEC platform, the control device may determine the DNS record identifier according to the identifier of the source MEC platform and the correspondence between the identifier of the source MEC platform and the DNS record identifier. In this case, the M application servers are typically all application servers deployed on the source MEC platform.

Or, for example, the control device may store the correspondence between the identifier of the source MEC platform and the DNS record identifier after querying the DNS record identifier from the NRF entity deployed in the core network for the previous time. Thus, if the DNS record identifier is within the validity period, after the control device receives the switching notification carrying the identifier of the source MEC platform, the DNS record identifier may be determined according to the identifier of the source MEC platform and the correspondence between the identifier of the source MEC platform and the DNS record identifier. In this case, the M application servers are also typically all application servers deployed on the source MEC platform.

Or, optionally, in a possible implementation manner, if none of the foregoing manners can determine the DNS record identifier, the control device obtains the DNS record identifier according to the switching notification at this time, which may specifically include: and the control equipment queries the DNS record identifier from the NRF entity according to the identifier of the source MEC platform. In this case, the M application servers are also typically all application servers deployed on the source MEC platform. Optionally, after the control device queries the DNS record identifier from the NRF entity, the corresponding relationship between the DNS record identifier and the identifier of the source MEC platform may be cached locally for a period of time, and when the DNS record identifier is subsequently required, the DNS record identifier may be obtained locally according to the above implementation manner, so that the number of times that the control device queries the core network may be reduced, where the caching time is determined by the control device itself, which is not specifically limited in this embodiment of the present application.

And S608, the control device sends an application trigger request to the terminal, so that the terminal receives the application trigger request from the control device. The application trigger request carries a DNS refresh message, and the DNS refresh message carries a DNS record identifier and is used for indicating to refresh a source DNS record corresponding to the DNS record identifier.

Optionally, the application trigger request in the embodiment of the present application may refer to an application trigger request in an application trigger mechanism shown in fig. 2, where the application trigger request may carry a DNS refresh message in a trigger load of the application trigger request in addition to the parameter shown in fig. 2, and this is not specifically limited in the embodiment of the present application.

Optionally, the DNS refresh message in the embodiment of the present application may indicate a refresh action. For example, a "refresh action" field may be defined in the DNS refresh message, so that after the terminal parses the application trigger request to obtain the DNS refresh message, according to the "refresh action" field, it may be determined that the source DNS record corresponding to the DNS record identifier needs to be refreshed. Or, the refresh action may be implicitly indicated by an identifier of the terminal application carried in the application trigger request, specifically, after the terminal parses the application trigger request, the identifier of the terminal application may be obtained, and then the DNS refresh request may be sent to the corresponding terminal application according to the identifier of the terminal application, where the terminal application is used to specially process the application trigger request, and the following description of step S609 may be specifically referred to, and details are not repeated here.

Optionally, in this embodiment of the present application, if M is a positive integer not less than 2, the DNS record identifier may be an aggregated IP address field, so that the length or number of contents in the DNS refresh message may be reduced, and thus signaling resources may be saved. For example, if the source IP address corresponding to each application server in the M application servers is 1.1.1.1, 1.1.1.2, 1.1.1.3, 1.1.1.4, and 1.1.1.5, respectively, the source IP addresses may be converged to 1.1.1.1-1.1.1.5; or, if the IP address segment of the source IP address corresponding to each application server in the M application servers is 1.1.1.1 to 1.1.1.100 and 1.1.1.111 to 1.1.1.200, the IP address segments may be aggregated into 1.1.1.1 to 1.1.1.200, and the aggregation manner is not particularly limited in this embodiment of the present application. If the DNS record identifier is carried in the handover notification, the IP address aggregation process may be implemented by the SMF entity or the control device; if the DNS record is acquired locally in the control equipment, the process of the IP address convergence is realized by the control equipment; if the DNS record is obtained by querying from an NRF entity, the above IP address aggregation process is implemented by the control device, or may be implemented by the NRF entity, which is not specifically limited in this embodiment of the present application.

Optionally, as shown in fig. 6, sending, by the control device, the application trigger request to the terminal needs to be forwarded through the NEF entity, the AMF entity, and the target access device, where the control device may be replaced with the application server in fig. 2, which may specifically refer to the application trigger flow shown in fig. 2, and details are not described here again.

And S609, the terminal deletes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message carried in the application trigger request.

As described in fig. 2, a terminal that must support an application triggering mechanism may use the application triggering procedure shown in fig. 2. Therefore, in the embodiment of the present application, if the application trigger request in the application trigger mechanism is to be reused, the terminal must support the application trigger mechanism, for example, as described in fig. 2, a specific terminal application or a service provided by the terminal OS may be provided for processing the application trigger request. Meanwhile, in the embodiment of the application, because the DNS refresh message is carried in the application trigger request, the terminal application or the service provided by the terminal OS is required to have a function or a service for processing the DNS refresh message, so that after the terminal OS system obtains the application trigger request, the source DNS record corresponding to the DNS record identifier can be searched according to the DNS refresh message carried in the application trigger request, and the source DNS record corresponding to the DNS record identifier is deleted; or after the terminal OS obtains the application trigger request, the application trigger request may be sent to the corresponding terminal application, and the terminal application searches for the source DNS record corresponding to the DNS record identifier according to the DNS refresh message carried in the application trigger request, and then deletes the source DNS record corresponding to the DNS record identifier.

S610, the terminal sends an application trigger response to the control device, so that the control device receives the trigger response from the terminal and the application trigger response. Wherein the application trigger response is used for indicating that the terminal has received the application trigger request.

Optionally, as shown in fig. 6, sending, by the terminal, the application trigger response to the control device needs to be forwarded through the target access device, the AMF entity, and the NEF entity, where the control device may be replaced with the application server in fig. 2, which may specifically refer to the application trigger flow shown in fig. 2, and details are not described here again.

S611, the terminal determines that the first application server needs to be accessed, where the first application server is one of the M application servers that is also deployed on the target MEC platform.

Since the terminal has deleted the corresponding relationship between the domain name of the first application server and the corresponding source IP address in step S609, after the terminal determines that the first application server needs to be accessed, the corresponding DNS record will not be queried in the local cache, and step S612 will be executed.

S612, the terminal sends a DNS resolution request to a second DNSP entity on the target MEC platform, so that the second DNSP entity receives the DNS resolution request from the terminal. The DNS resolution request is for requesting a target IP address corresponding to a domain name of the first application server.

Optionally, the DNS resolution request may carry a domain name of the first application server or other information that may be used to uniquely identify the first application server, which is not specifically limited in this embodiment of the present application.

Optionally, as shown in fig. 6, the terminal sends the DNS resolution request to the second DNSP entity and needs to forward the DNS resolution request through the target access device and the target UPF entity deployed on the target MEC platform, specifically, after the terminal sends the DNS resolution request, the target UPF entity identifies the DNS resolution request and forwards the DNS resolution request to the second DNSP entity for processing, which is transparent to the terminal, and this is not specifically limited in this embodiment of the present application.

S613, the second DNSP entity sends a DNS resolution response to the terminal, so that the terminal receives the DNS resolution response from the second DNSP entity. And the DNS analysis response carries a target IP address corresponding to the domain name of the first application server.

Optionally, as shown in fig. 6, sending, by the second DNSP entity, the DNS resolution response to the terminal needs to be forwarded through the target UPF entity and the target access device, which is not specifically limited in this embodiment of the present application.

S614, the terminal stores a second DNS record, and the second DNS record is the corresponding relation between the domain name of the first application server and the corresponding target IP address.

In this way, in the validity period of the second DNS record, if the terminal needs to access the first application server, the terminal may directly initiate a connection request to the first application server corresponding to the target IP address in the second DNS record according to the second DNS record, which may specifically refer to the existing implementation manner and is not described herein again.

Optionally, in this embodiment of the application, each application server that needs to be accessed by a terminal that is also deployed on the target MEC platform among the M application servers may be executed according to the manner of steps S611 to S614, which is not described herein again.

Optionally, in this embodiment of the application, after the terminal deletes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message carried in the application trigger request (step S609), for each application server of the M application servers that is also deployed on the target MEC platform, the execution is directly performed in the manner of steps S612 to S614, which is not specifically limited in this embodiment of the application.

Optionally, in this embodiment of the application, for an application server that is not deployed on the target MEC platform among the M application servers, the terminal may also send a DNS resolution request to the second DNSP entity, and since the application server is not deployed on the target MEC platform, the second DNSP entity may send the DNS resolution request to an actual DNS server and send the obtained IP address to the terminal, which is not specifically limited in this embodiment of the application.

In the application server switching method provided by the embodiment of the application server, the control device may send the DNS refresh message to the terminal when the terminal is switched to access from the source MEC platform to the target MEC platform, so that the terminal may refresh the source DNS record corresponding to the DNS record identifier according to the DNS refresh message to obtain the target DNS record. On one hand, after the MEC platform is switched, the source DNS record corresponding to the DNS record identifier can be refreshed in time to obtain the target DNS record, and then the application server deployed on the target MEC platform can be directly accessed according to the target DNS record, so that the application server can be switched in time; on the other hand, in the switching process of the application server, the terminal application and the application server deployed on the MEC platform do not need to be perceived, so that the terminal application and the application server deployed on the MEC platform do not need to be adapted and developed, and conditions can be created for large-scale application of the MEC. That is to say, based on the application server switching method, the application server can be switched in time in the scenario that the terminal is switched from the source MEC platform to the target MEC platform for access, and the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform do not need to be adapted and developed, thereby creating conditions for large-scale application of the MEC. Meanwhile, when the scheme sends the DNS refresh message, the existing application trigger flow can be reused, so that the implementation complexity of the scheme is simplified, and the implementability of the scheme is increased.

The actions of the terminal and the control device in steps S601 to S614 may be executed by the processor 501 in the communication device 500 shown in fig. 5 calling the application program code stored in the memory 503, which is not limited in this embodiment of the present application.

Optionally, taking an application architecture of the application server switching system shown in fig. 4 in a 5G network as an example, as shown in fig. 7, another application server switching method provided in the embodiment of the present application is provided, where the method includes the following steps:

S701-S708 and the synchronization steps S601-S608 refer to the embodiment shown in fig. 6, which is not described herein again.

S709 and the synchronization step S610 may refer to the embodiment shown in fig. 6, which are not described herein again.

S710-S712, similar to steps S611-S613, except that in the embodiment shown in fig. 6, after step S610, the terminal may delete the DNS refresh message; in the embodiment shown in fig. 7, after step S708, the terminal needs to cache the DNS refresh message. In this way, after the terminal determines that the first application server needs to be accessed (step S710), since the terminal further stores the corresponding relationship between the domain name of the first application server and the corresponding source IP address, the terminal must determine whether the DNS record needs to be refreshed by combining the DNS refresh message, for example, if the first application server is one of the M application servers and the first application server is also deployed on the target MEC platform, the terminal may continue to perform subsequent steps S711-S712, otherwise, a connection request is initiated to the application server corresponding to the source IP address, which is not specifically limited in this embodiment of the present application.

Or, optionally, in this embodiment of the application, after step S708, the terminal may also not cache the DNS refresh message, but after obtaining the DNS refresh message, add a flag in the source DNS record corresponding to the DNS record identifier according to the DNS record identifier carried in the DNS refresh message, so as to distinguish that the source DNS record is to be refreshed. In this way, after the terminal determines that the first application server needs to be accessed (step S710), if the corresponding source DNS record has the flag, it may be determined that the source DNS record needs to be refreshed, and then the terminal may continue to execute subsequent steps S711-S712, otherwise, a connection request is initiated to the application server corresponding to the source IP address, which is not specifically limited in this embodiment of the application.

Or, optionally, after step S708, the terminal may also not cache the DNS refresh message, but after acquiring the DNS refresh message, modify, according to the DNS record identifier carried in the DNS refresh message, the TTL parameter of the source DNS record corresponding to the DNS record identifier to an invalid value. In this way, after the terminal determines that the first application server needs to be accessed (step S710), if the TTL parameter in the corresponding source DNS record is an invalid value, it may be determined that the source DNS record needs to be refreshed, and then the terminal may continue to perform subsequent steps S711-S712, otherwise, a connection request is initiated to the application server corresponding to the source IP address, which is not specifically limited in this embodiment of the application.

The specific implementation of steps S710-S712 can refer to the embodiment shown in fig. 6, and is not described herein again.

S713, the terminal replaces the source IP address corresponding to the domain name of the first application server in the first DNS record with the target IP address corresponding to the domain name of the first application server to obtain a second DNS record.

The first DNS record is the corresponding relation between the domain name of the first application server and the corresponding source IP address; the second DNS record is a correspondence between the domain name of the first application server and the corresponding target IP address.

Optionally, in this embodiment of the application, each application server that needs to be accessed by a terminal that is also deployed on the target MEC platform among the M application servers may be executed according to the manner of steps S710 to S713, which is not described herein again.

Optionally, in this embodiment of the application, after the terminal receives the application trigger request from the control device, according to the DNS refresh message carried in the application trigger request, each application server, which is also deployed on the target MEC platform, in the M application servers may be directly executed according to the manner of steps S711 to S713, which is not specifically limited in this embodiment of the application.

In the application server switching method provided by the embodiment of the application server, the control device may send the DNS refresh message to the terminal when the terminal is switched to access from the source MEC platform to the target MEC platform, so that the terminal may refresh the source DNS record corresponding to the DNS record identifier according to the DNS refresh message to obtain the target DNS record. On one hand, after the MEC platform is switched, the source DNS record corresponding to the DNS record identifier can be refreshed in time to obtain the target DNS record, and then the application server deployed on the target MEC platform can be directly accessed according to the target DNS record, so that the application server can be switched in time; on the other hand, in the switching process of the application server, the terminal application and the application server deployed on the MEC platform do not need to be perceived, so that the terminal application and the application server on the MEC platform do not need to be adapted and developed, and conditions can be created for large-scale application of the MEC. That is to say, based on the application server switching method, the application server can be switched in time in the scenario that the terminal is switched from the source MEC platform to the target MEC platform for access, and the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform do not need to be adapted and developed, thereby creating conditions for large-scale application of the MEC. Meanwhile, when the scheme sends the DNS refresh message, the existing application trigger flow can be reused, so that the implementation complexity of the scheme is simplified, and the implementability of the scheme is increased.

The actions of the terminal and the control device in steps S701 to S713 may be executed by the processor 501 in the communication device 500 shown in fig. 5 calling the application program code stored in the memory 503, which is not limited in this embodiment of the present application.

Optionally, taking an application architecture of the application server switching system shown in fig. 4 in a 5G network as an example, as shown in fig. 8, another application server switching method provided in the embodiment of the present application is provided, where the method includes the following steps:

s801 to S803 and synchronization steps S601 to S603 may refer to the embodiment shown in fig. 6, and are not described herein again.

S804 and the synchronization step S605 refer to the embodiment shown in fig. 6, which are not described herein again.

S805, the SMF entity acquires the DNS record identification.

Optionally, in a possible implementation manner, the acquiring, by the SMF entity, the DNS record identifier may specifically include: and the SMF entity determines the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier.

For example, if the SMF entity configures information related to the application server deployed on the source MEC platform in step S801, the SMF entity may store a correspondence between the identifier of the source MEC platform and the DNS record identifier. Thus, after determining that the MEC platform is switched, the SMF entity may determine the DNS record identifier according to the identifier of the source MEC platform and the correspondence between the identifier of the source MEC platform and the DNS record identifier. In this case, the M application servers are typically all application servers deployed on the source MEC platform.

Or, for example, the SMF entity may store the correspondence between the identifier of the source MEC platform and the DNS record identifier after querying the DNS record identifier from the NRF entity deployed in the core network for the previous time. Thus, if the DNS record identifier is within the validity period, after the SMF entity determines that the MEC platform is switched, the DNS record identifier may be determined according to the identifier of the source MEC platform and the correspondence between the identifier of the source MEC platform and the DNS record identifier. In this case, the M application servers are also typically all application servers deployed on the source MEC platform.

Or, optionally, in a possible implementation manner, if none of the foregoing manners can determine the DNS record identifier corresponding to the source DNS record, the obtaining, by the SMF entity, the DNS record identifier may specifically include: and the SMF entity queries the DNS record identification from the NRF entity according to the identification of the source MEC platform. In this case, the M application servers are also typically all application servers deployed on the source MEC platform. Optionally, after the SMF entity queries the DNS record identifier from the NRF entity, the corresponding relationship between the DNS record identifier and the identifier of the source MEC platform may be cached locally for a period of time, and when the DNS record identifier is subsequently required, the DNS record identifier may be locally obtained according to the above implementation manner, so that the number of times that the SMF entity queries the core network may be reduced, where the caching time is determined by the SMF entity itself, which is not specifically limited in this embodiment of the present application.

S806, the SMF entity sends a handover notification to the AMF entity, so that the AMF entity receives the handover notification from the SMF entity. The switching notification carries a DNS refreshing message, and the DNS refreshing message carries a DNS record identifier and is used for indicating to refresh a source DNS record corresponding to the DNS record identifier.

Optionally, in this embodiment of the present application, if M is a positive integer not less than 2, the DNS record identifier may be an aggregated IP address field, so that the length or number of contents in the DNS refresh message may be reduced, and thus signaling resources may be saved. The related description may refer to the embodiment shown in fig. 6, and will not be repeated herein.

S807, the AMF entity sends NAS message 1 to the terminal, so that the terminal receives NAS message 1 from the AMF entity. The NAS message 1 carries a DNS refresh message, and the DNS refresh message carries a DNS record identifier, which is used to indicate to refresh a source DNS record corresponding to the DNS record identifier.

Optionally, in this embodiment of the present application, the DNS refresh message may be carried in an additional information (additional information) cell or other fields of the NAS message 1, which is not specifically limited in this embodiment of the present application.

Optionally, the DNS refresh message in the embodiment of the present application may indicate a refresh action. For example, a "refresh action" field may be defined in the DNS refresh message, so that after the terminal parses the NAS message 1 to obtain the DNS refresh message, according to the "refresh action" field, it may be determined that the source DNS record corresponding to the DNS record identifier needs to be refreshed. Or, the refresh action may be implicitly indicated by carrying the identifier of the terminal application in the handover notification and the NAS message 1, specifically, after the terminal parses the NAS message 1, the terminal may obtain the identifier of the terminal application, and then may send the DNS refresh message to the corresponding terminal application according to the identifier of the terminal application, where the terminal application is used to specially process the DNS refresh message, and specifically, reference may be made to the description of step S808, which is not described herein again.

Optionally, as shown in fig. 8, sending, by the AMF entity, the NAS message 1 to the terminal needs to be forwarded by the target access device, which is not specifically limited in this embodiment of the present application.

And S808, the terminal deletes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message carried in the NAS message 1.

Optionally, in this embodiment of the present application, a specific terminal application or terminal OS may be provided to provide a service for processing the DNS refresh message. In this way, the terminal baseband chip recognizes that the message is the DNS refresh message after receiving the NAS message 1, and can transmit the DNS refresh message to the terminal OS. Thus, after the terminal OS system acquires the DNS refresh message, it can search for the source DNS record corresponding to the DNS record identifier according to the DNS refresh message, and then delete the source DNS record corresponding to the DNS record identifier; or after the terminal OS obtains the DNS refresh message, the terminal OS may send the DNS refresh message to a corresponding terminal application, and the terminal application searches for the source DNS record corresponding to the DNS record identifier according to the DNS refresh message, and then deletes the source DNS record corresponding to the DNS record identifier, which is not specifically limited in this embodiment of the present application.

Optionally, in this embodiment of the present application, if a specific terminal application is provided to process the DNS refresh message, the NAS message 1 may also carry an identifier of the terminal application, which is not specifically limited in this embodiment of the present application.

And S809, the terminal sends the NAS message 2 to the AMF entity so that the AMF entity receives the NAS message 2 from the terminal. Wherein, the NAS message 2 carries the DNS refresh response. The DNS refresh response application indicates that the terminal has received the DNS refresh request.

Optionally, in this embodiment of the present application, the DNS refresh response may be carried in an additional information cell or other fields of the NAS message 2, which is not specifically limited in this embodiment of the present application.

Optionally, as shown in fig. 8, the terminal sends the NAS message 2 to the AMF entity and needs to forward the message through the target access device, which is not specifically limited in this embodiment of the present application.

S810-S813 and synchronization steps S611-S614 refer to the embodiment shown in fig. 6, and are not described herein again.

Optionally, in this embodiment of the present application, in a process of switching the terminal from the source MEC platform to the target MEC platform for access, step S805 may be executed before step S107 shown in fig. 2, and further, the DNS refresh message is carried in the bearer modification response in step S107, so that step S806 in this embodiment of the present application may not be executed, thereby saving signaling resources, which is not specifically limited in this embodiment of the present application. For example, the DNS refresh message may be carried in the bearer modification response by adding a DNS refresh message field in the bearer modification response; the DNS refresh message may also be carried in a Protocol Configuration Option (PCO) cell in the bearer modification response, which is not specifically limited in this embodiment of the present invention.

Optionally, in this embodiment of the application, after the terminal receives the NAS message 1 from the AMF entity, reference may be made to steps S710 to S713 shown in fig. 7 to refresh the source DNS record corresponding to the DNS record identifier, which may specifically refer to the embodiment shown in fig. 7, and this embodiment of the application is not described herein again.

In the application server switching method provided by the embodiment of the application server switching method, the SMF entity may send the DNS refresh message to the terminal when the terminal is switched from the source MEC platform to the target MEC platform for access, so that the terminal may refresh the source DNS record corresponding to the DNS record identifier according to the DNS refresh message to obtain the target DNS record. On one hand, after the MEC platform is switched, the source DNS record corresponding to the DNS record identifier can be refreshed in time to obtain the target DNS record, and then the application server deployed on the target MEC platform can be directly accessed according to the target DNS record, so that the application server can be switched in time; on the other hand, in the switching process of the application server, the terminal application and the application server deployed on the MEC platform do not need to be perceived, so that the terminal application and the application deployed on the MEC platform do not need to be adapted and developed, and conditions can be created for large-scale application of the MEC. That is to say, based on the application server switching method, the application server can be switched in time in the scenario that the terminal is switched from the source MEC platform to the target MEC platform for access, and the application server deployed on the MEC platform and the terminal application corresponding to the application server deployed on the MEC platform do not need to be adapted and developed, thereby creating conditions for large-scale application of the MEC. Meanwhile, compared with the embodiments shown in fig. 6 or fig. 7, the embodiments of the present application do not need to limit that the terminal must support the application triggering mechanism, thereby expanding the application range of the scheme.

The actions of the terminal and the SMF entity in steps S801 to S813 may be executed by the processor 501 in the communication device 500 shown in fig. 5 calling the application program code stored in the memory 503, which is not limited in this embodiment of the present application.

It should be noted that, in the embodiments of the present application, the provided application server switching method is applied to the MEC platform as an example, and of course, the application server switching method may also be applied to other scenarios similar to the MEC platform, and the embodiments of the present application are not limited to this specifically.

The above-mentioned scheme provided by the embodiment of the present application is introduced mainly from the perspective of interaction between network elements. It is to be understood that the terminal, the session management function entity and the control device include corresponding hardware structures and/or software modules for performing the respective functions in order to realize the functions. Those of skill in the art would readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. 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.

In the embodiment of the present application, the terminal, the session management function entity, and the control device may be divided into function modules according to the above method example, for example, each function module may be divided corresponding to each function, or two or more functions may be integrated into one processing module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. It should be noted that, in the embodiment of the present application, the division of the module is schematic, and is only one logic function division, and there may be another division manner in actual implementation.

For example, in the case of dividing the functional modules in an integrated manner, fig. 9 shows a schematic structural diagram of an apparatus 90. The device 90 may be a terminal, or may be a chip in the terminal, which is not specifically limited in this embodiment of the present application. Wherein the device 90 comprises: a transceiver module 901 and a processing module 902. A transceiver module 901, configured to receive a DNS refresh message, where the DNS refresh message carries a DNS record identifier, and the DNS refresh message is used to indicate to refresh a source DNS record corresponding to the DNS record identifier; a processing module 902, configured to refresh, according to the DNS refresh message, a source DNS record corresponding to the DNS record identifier to obtain a target DNS record. For the description of the source DNS record and the target DNS record, reference may be made to the above method embodiment, which is not described herein again.

Optionally, the processing module 902 is specifically configured to: deleting a source DNS record corresponding to the DNS record identifier according to the DNS refresh message; for each application server, which is also deployed on the target MEC platform among the M application servers and needs to be accessed by the terminal, the following processing is performed for the first application server: under the condition that a terminal needs to access a first application server, sending a DNS analysis request, wherein the DNS analysis request is used for requesting a target IP address corresponding to a domain name of the first application server; and receiving a target IP address corresponding to the domain name of the first application server, and storing the corresponding relation between the domain name of the first application server and the target IP address corresponding to the domain name of the first application server.

Optionally, the transceiver module 901 is specifically configured to: and receiving an application trigger request from the control equipment, wherein the application trigger request carries a DNS refresh message.

Or, optionally, the transceiver module 901 is specifically configured to: a DNS refresh message is received from a session management entity.

All relevant contents of each step related to the above method embodiment may be referred to the functional description of the corresponding functional module, and are not described herein again.

In the present embodiment, the apparatus 90 is presented in the form of dividing each functional module in an integrated manner. A "module" as used herein may refer to an application-specific integrated circuit (ASIC), an electronic circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other devices that provide the described functionality.

In a simple embodiment, one skilled in the art will appreciate that the device 90 may take the form shown in FIG. 5.

For example, the processor 501 in fig. 5 may execute the instructions by calling a computer stored in the memory 503, so that the apparatus 90 executes the application server switching method in the above method embodiment.

In particular, the functions/implementation procedures of the transceiver module 901 and the processing module 902 in fig. 9 can be implemented by the processor 501 in fig. 5 calling a computer executing instruction stored in the memory 503. Alternatively, the function/implementation procedure of the processing module 902 in fig. 9 may be implemented by the processor 501 in fig. 5 calling a computer executing instruction stored in the memory 503, and the function/implementation procedure of the transceiving module 902 in fig. 9 may be implemented by the communication interface 504 in fig. 5.

Alternatively, when the apparatus 90 is a chip, the functions/implementation processes of the transceiver module 901 can also be implemented by pins or circuits. Alternatively, when the apparatus 90 is a chip, the memory 503 may be a storage unit in the chip, such as a register, a cache, and the like. Of course, when the apparatus 90 is a terminal, the memory 503 may be a storage unit located outside the chip in the terminal, and this embodiment of the present application is not particularly limited thereto.

Since the apparatus provided in the embodiment of the present application can be used to execute the method for switching the application server, the technical effects obtained by the apparatus can refer to the method embodiment, and are not described herein again.

For example, in the case where the respective functional modules are divided in an integrated manner, fig. 10 shows a schematic configuration of a control apparatus 100. The control device 100 may comprise a transceiver module 1001 and a processing module 1002. A transceiver module 1001, configured to receive a handover notification from a session management entity, where the handover notification is used to indicate that MEC platform handover occurs in a terminal; a processing module 1002, configured to obtain a DNS record identifier according to the switching notification; the transceiving module 1001 is further configured to send a DNS refresh message to the terminal, where the DNS refresh message carries a DNS record identifier, and the DNS refresh message is used to indicate to refresh a source DNS record corresponding to the DNS record identifier, where reference may be made to the above method embodiment for a description related to the source DNS record, and details are not described here again.

Optionally, the transceiver module 1001 is configured to send a DNS refresh message to the terminal, and includes: the terminal is used for sending an application trigger request to the terminal, and the application trigger request carries a DNS refresh message.

Optionally, the transceiver module 1001 is further configured to send a subscription request to the session management entity, where the subscription request is used to request a subscription to a handover event of the MEC platform.

In one possible implementation, the switching notification carries a DNS record identifier; the processing module 1002 is specifically configured to: and obtaining the DNS record identification from the switching notice.

In one possible implementation, the switching notification carries an identifier of the source MEC platform; the processing module 1002 is specifically configured to: and determining the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier.

Optionally, the processing module 1002 is further configured to determine that the DNS record identifier is within the validity period.

In one possible implementation, the switching notification carries an identifier of the source MEC platform; the processing module 1002 is specifically configured to: and inquiring the DNS record identification from the warehouse functional entity according to the identification of the source MEC platform.

In the present embodiment, the control apparatus 100 is presented in the form of dividing each functional module in an integrated manner. A "module" herein may refer to a particular ASIC, a circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other device that provides the described functionality. In a simple embodiment, one skilled in the art will appreciate that the control device 100 may take the form shown in FIG. 5.

For example, the processor 501 in fig. 5 may cause the control device 100 to execute the application server switching method in the above-described method embodiment by calling a computer stored in the memory 503 to execute the instructions.

In particular, the functions/implementation procedures of the processing module 1002 and the transceiver module 1001 in fig. 10 may be implemented by the processor 501 in fig. 5 calling a computer executing instructions stored in the memory 503. Alternatively, the function/implementation procedure of the processing module 1002 in fig. 10 may be implemented by the processor 501 in fig. 5 calling a computer executing instruction stored in the memory 503, and the function/implementation procedure of the transceiving module 1001 in fig. 10 may be implemented by the communication interface 504 in fig. 5.

Since the control device provided in the embodiment of the present application can be used to execute the method for switching the application server, the technical effect obtained by the control device can refer to the method embodiment, and will not be described herein again.

For example, in a case where the functional modules are divided in an integrated manner, fig. 11 shows a schematic structural diagram of the session management entity 110. The session management entity 110 may comprise a transceiver module 1101 and a processing module 1102. A processing module 1102, configured to obtain a DNS record identifier; the transceiver module 1101 is configured to send a DNS refresh message to the terminal, where the DNS refresh message carries a DNS record identifier, and the DNS refresh message is used to indicate to refresh a source DNS record corresponding to the DNS record identifier, where reference may be made to the above method embodiment for related description of the source DNS record, and details are not described here again.

In a possible implementation manner, the processing module 1102 is specifically configured to: and determining the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier.

Optionally, the processing module 1102 is further configured to determine that the DNS record identifier is within the validity period.

In a possible implementation manner, the processing module 1102 is specifically configured to: and inquiring the DNS record identification from the warehouse functional entity according to the identification of the source MEC platform.

In the present embodiment, the session management entity 110 is presented in a form of dividing each functional module in an integrated manner. A "module" herein may refer to a particular ASIC, a circuit, a processor and memory that execute one or more software or firmware programs, an integrated logic circuit, and/or other device that provides the described functionality. In a simple embodiment, the session management entity 110 may take the form shown in fig. 5, as will be appreciated by those skilled in the art.

For example, the processor 501 in fig. 5 may cause the session management entity 110 to execute the application server switching method in the above-described method embodiment by calling a computer executing instruction stored in the memory 503.

In particular, the functions/implementation processes of the processing module 1102 and the transceiver module 1101 in fig. 11 may be implemented by the processor 501 in fig. 5 calling a computer executing instructions stored in the memory 503. Alternatively, the function/implementation procedure of the processing module 1102 in fig. 11 may be implemented by the processor 501 in fig. 5 calling a computer executing instruction stored in the memory 503, and the function/implementation procedure of the transceiver module 1101 in fig. 11 may be implemented by the communication interface 504 in fig. 5.

Since the session management entity provided in the embodiment of the present application can be used to execute the method for switching the application server, the technical effect obtained by the session management entity can refer to the method embodiment, and will not be described herein again.

In the above-described embodiment, the apparatus 90, the control device 100, and the session management entity 110 are each presented in the form of dividing each functional module in an integrated manner. Of course, the embodiment of the present application may also correspond to each function partitioning apparatus, each control device, and each function module of the session management entity, and this is not specifically limited in the embodiment of the present application.

Optionally, an embodiment of the present application provides a chip system, where the chip system includes a processor, and is configured to support a control device to implement the foregoing application server switching method, for example, to obtain a DNS record identifier according to a switching notification. In one possible design, the system-on-chip further includes a memory. The memory is used for storing program instructions and data necessary for controlling the device. The chip system may be formed by a chip, and may also include a chip and other discrete devices, which is not specifically limited in this embodiment of the present application.

Optionally, an embodiment of the present application provides a chip system, where the chip system includes a processor, and is configured to support a session management entity to implement the foregoing application server switching method, for example, to obtain a DNS record identifier. In one possible design, the system-on-chip further includes a memory. The memory is used for storing program instructions and data necessary for the session management entity. The chip system may be formed by a chip, and may also include a chip and other discrete devices, which is not specifically limited in this embodiment of the present application.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented using a software program, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. The procedures or functions described in accordance with the embodiments of the present application are all or partially generated upon loading and execution of computer program instructions on a computer. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or can comprise one or more data storage devices, such as a server, a data center, etc., that can be integrated with the medium. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

While the present application has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a review of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the word "a" or "an" does not exclude a plurality. A single processor or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Although the present application has been described in conjunction with specific features and embodiments thereof, it will be evident that various modifications and combinations can be made thereto without departing from the spirit and scope of the application. Accordingly, the specification and figures are merely exemplary of the present application as defined in the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the present application. It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. An application server switching method is applied to a scene that a terminal is switched to access from a source mobile edge computing MEC platform to a target MEC platform, and is characterized by comprising the following steps:

the terminal receives a Domain Name System (DNS) refreshing message, wherein the DNS refreshing message carries a DNS record identifier and is used for indicating and refreshing a source DNS record corresponding to the DNS record identifier, the source DNS record comprises a corresponding relation between a domain name of each application server in M application servers deployed on a source MEC platform and a corresponding source Internet Protocol (IP) address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer;

and the terminal refreshes a source DNS record corresponding to the DNS record identifier according to the DNS refreshing message to obtain a target DNS record, wherein the target DNS record comprises a corresponding relation between a domain name of an application server which is also deployed on the target MEC platform in the M application servers and a corresponding target IP address, and the target IP address is an IP address associated with the target MEC platform.

2. The method according to claim 1, wherein the terminal refreshes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message to obtain the target DNS record, including:

the terminal deletes the source DNS record corresponding to the DNS record identifier according to the DNS refresh message;

for each application server, which is also deployed on the target MEC platform among the M application servers and needs to be accessed by the terminal, the terminal processes the application servers in the following manner for the first application server:

under the condition that the terminal needs to access the first application server, the terminal sends a DNS analysis request, wherein the DNS analysis request is used for requesting a target IP address corresponding to the domain name of the first application server;

and the terminal receives the target IP address corresponding to the domain name of the first application server and stores the corresponding relation between the domain name of the first application server and the target IP address corresponding to the domain name of the first application server.

3. Method according to claim 1 or 2, wherein the terminal receives a DNS refresh message comprising:

and the terminal receives an application trigger request from control equipment, wherein the application trigger request carries the DNS refresh message.

4. Method according to claim 1 or 2, wherein the terminal receives a DNS refresh message comprising:

and the terminal receives the DNS refresh message from a session management entity.

5. An application server switching method is applied to a scene that a terminal is switched to access from a source mobile edge computing MEC platform to a target MEC platform, and is characterized by comprising the following steps:

the control equipment receives a switching notice from a session management entity, wherein the switching notice is used for indicating the terminal to generate MEC platform switching;

the control equipment acquires a Domain Name System (DNS) record identifier according to the switching notification;

the control device sends a DNS refresh message to the terminal, wherein the DNS refresh message carries a DNS record identifier, the DNS refresh message is used for indicating to refresh a source DNS record corresponding to the DNS record identifier, the source DNS record comprises a corresponding relation between a domain name of each application server in M application servers deployed on the source MEC platform and a corresponding source Internet protocol IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer.

6. The method of claim 5, wherein the controlling device sends a DNS refresh message to the terminal, comprising:

and the control equipment sends an application trigger request to the terminal, wherein the application trigger request carries the DNS refreshing message.

7. The method according to claim 5 or 6, wherein before the control device receives the handover notification from the session management entity, the method further comprises:

the control device sends a subscription request to the session management entity, wherein the subscription request is used for requesting to subscribe a switching event of the MEC platform.

8. The method according to any of claims 5-7, wherein the handover notification carries the DNS record identity;

the control device obtains a DNS record identifier according to the switching notification, including:

and the control equipment acquires the DNS record identifier from the switching notice.

9. The method according to any of claims 5-7, wherein the handover notification carries an identification of the source MEC platform;

and the control equipment determines the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier.

10. The method of claim 9, prior to the control device determining the DNS record identification, further comprising:

the control device determines that the DNS record identification is within a validity period.

11. The method according to any of claims 5-7, wherein the handover notification carries an identification of the source MEC platform;

the control device obtains a DNS record identifier according to the switching notification, including: and the control equipment queries the DNS record identifier from a warehouse functional entity according to the identifier of the source MEC platform.

12. An application server switching method is applied to a scene that a terminal is switched to access from a source mobile edge computing MEC platform to a target MEC platform, and is characterized by comprising the following steps:

a session management entity acquires a Domain Name System (DNS) record identifier;

the session management entity sends a DNS refresh message to the terminal, wherein the DNS refresh message carries a DNS record identifier, and the DNS refresh message is used for indicating to refresh a source DNS record corresponding to the DNS record identifier, wherein the source DNS record comprises a corresponding relation between a domain name of each application server in M application servers deployed on the source MEC platform and a corresponding source Internet protocol IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer.

13. The method of claim 12, wherein the session management entity obtaining the DNS record identifier comprises:

and the session management entity determines the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier.

14. The method of claim 13, prior to the session management entity determining the DNS record identification, further comprising:

the session management entity determines that the DNS record identification is within a validity period.

15. The method of claim 12, wherein the session management entity obtaining the DNS record identifier comprises:

and the session management entity queries the DNS record identifier from a warehouse functional entity according to the identifier of the source MEC platform.

16. A terminal, characterized in that the terminal comprises: a transceiver module and a processing module;

the receiving and sending module is configured to receive a domain name system DNS refresh message, where the DNS refresh message carries a DNS record identifier, and the DNS refresh message is used to indicate to refresh a source DNS record corresponding to the DNS record identifier, where the source DNS record includes a correspondence between a domain name of each application server in M application servers deployed on a source mobile edge computing MEC platform and a corresponding source internet protocol IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer;

the processing module is configured to refresh, according to the DNS refresh message, a source DNS record corresponding to the DNS record identifier to obtain a target DNS record, where the target DNS record includes a correspondence between a domain name of an application server that is also deployed on a target MEC platform among the M application servers and a corresponding target IP address, and the target IP address is an IP address associated with the target MEC platform.

17. The terminal of claim 16, wherein the processing module is specifically configured to:

deleting the source DNS record corresponding to the DNS record identifier according to the DNS refresh message;

for each application server, which is also deployed on the target MEC platform among the M application servers and needs to be accessed by the terminal, processing the application servers in the following manner for the first application server:

sending a DNS analysis request under the condition that the terminal needs to access the first application server, wherein the DNS analysis request is used for requesting a target IP address corresponding to the domain name of the first application server;

and receiving the target IP address corresponding to the domain name of the first application server, and storing the corresponding relation between the domain name of the first application server and the target IP address corresponding to the domain name of the first application server.

18. The terminal according to claim 16 or 17, wherein the transceiver module is specifically configured to:

and receiving an application trigger request from the control equipment, wherein the DNS refresh message is carried in the application trigger request.

19. The terminal according to claim 16 or 17, wherein the transceiver module is specifically configured to:

receiving the DNS refresh message from a session management entity.

20. A control apparatus, characterized in that the control apparatus comprises: a transceiver module and a processing module;

the receiving and sending module is used for receiving a switching notice from a session management entity, wherein the switching notice is used for indicating that the mobile edge computing MEC platform switching occurs in a terminal;

the processing module is used for acquiring a domain name system DNS record identifier according to the switching notification;

the receiving and sending module is further configured to send a DNS refresh message to the terminal, where the DNS refresh message carries the DNS record identifier, and the DNS refresh message is used to indicate to refresh a source DNS record corresponding to the DNS record identifier, where the source DNS record includes a correspondence between a domain name of each application server in M application servers deployed on a source MEC platform and a corresponding source internet protocol IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer.

21. The control device according to claim 20, wherein the transceiving module is configured to send a DNS refresh message to the terminal, and comprises:

and the terminal is used for sending an application trigger request to the terminal, wherein the application trigger request carries the DNS refresh message.

22. The control apparatus according to claim 20 or 21,

the transceiver module is further configured to send a subscription request to the session management entity, where the subscription request is used to request a subscription to a handover event of the MEC platform.

23. The control device according to any of claims 20-22, wherein the switching notification carries the DNS record identity; the processing module is specifically configured to:

and acquiring the DNS record identifier from the switching notice.

24. The control apparatus according to any of claims 20-22, wherein the switching notification carries an identification of the source MEC platform; the processing module is specifically configured to:

and determining the DNS record identifier according to the identifier of the source MEC platform and the corresponding relation between the identifier of the source MEC platform and the DNS record identifier.

25. The control device of claim 24, wherein the processing module is further configured to determine that the DNS record identification is within a validity period.

26. The control apparatus according to any of claims 20-22, wherein the switching notification carries an identification of the source MEC platform; the processing module is specifically configured to:

and inquiring the DNS record identifier from a warehouse functional entity according to the identifier of the source MEC platform.

27. A session management entity, characterized in that the session management entity comprises: the device comprises a processing module and a transmitting-receiving module;

the processing module is used for acquiring a domain name system DNS record identifier;

the receiving and sending module is configured to send a DNS refresh message to a terminal, where the DNS refresh message carries a DNS record identifier, and the DNS refresh message is used to indicate to refresh a source DNS record corresponding to the DNS record identifier, where the source DNS record includes a correspondence between a domain name of each application server in M application servers deployed on a source mobile edge computing MEC platform and a corresponding source internet protocol IP address, the source IP address is an IP address associated with the source MEC platform, and M is a positive integer.

28. The session management entity of claim 27, wherein the processing module is specifically configured to:

29. The session management entity of claim 28, wherein the processing module is further configured to determine that the DNS record identifier is within a validity period.

30. The session management entity of claim 27, wherein the processing module is specifically configured to:

31. An application server apparatus, comprising a processor and a memory;

the memory is configured to store computer-executable instructions, and when the apparatus is running, the processor executes the computer-executable instructions stored by the memory to cause the apparatus to perform the application server switching method according to any one of claims 1 to 4.

32. The apparatus of claim 31, wherein the apparatus comprises a terminal or a chip within the terminal.

33. A control device, characterized in that the control device comprises a processor and a memory;

the memory is used for storing computer-executable instructions, and when the control device runs, the processor executes the computer-executable instructions stored by the memory to cause the control device to execute the application server switching method according to any one of claims 5 to 11.

34. A session management entity, characterized in that the session management entity comprises a processor and a memory;

the memory is configured to store computer-executable instructions, and when the session management entity is running, the processor executes the computer-executable instructions stored in the memory to cause the session management entity to perform the application server switching method according to any one of claims 12 to 15.

35. An application server switching system, characterized in that the application server switching system comprises a terminal according to any of claims 16-18 and a control device according to any of claims 20-26;

alternatively, the application server switching system comprises a terminal according to any of claims 16, 17 or 19 and a session management entity according to any of claims 27-30;

alternatively, the application server switching system comprises the terminal according to claim 32 and the control device according to claim 33;

alternatively, the application server switching system comprises a terminal according to claim 32 and a session management entity according to claim 34.