CN113301098A

CN113301098A - Path planning method, CDN connection establishing method, device and storage medium

Info

Publication number: CN113301098A
Application number: CN202110009154.7A
Authority: CN
Inventors: 郝保平; 李松林
Original assignee: Alibaba Group Holding Ltd
Current assignee: Alibaba Group Holding Ltd
Priority date: 2021-01-05
Filing date: 2021-01-05
Publication date: 2021-08-24

Abstract

The embodiment of the application provides a path planning method, a CDN connection establishing method, equipment and a storage medium. In the embodiment of the application, the CDN network includes not only CDN nodes participating in path planning but also backup CDN nodes not participating in path planning; when a path planning request is received, firstly, dynamic path planning is carried out based on CDN nodes participating in path planning in a CDN network, and under the condition that the path planning fails, appropriate backup CDN nodes are selected from backup CDN nodes not participating in the path planning, the backup CDN nodes are used as relay CDN nodes between the CDN nodes requesting the path planning and a source station so as to obtain a back-source path, the back-source path can be successfully planned based on the backup CDN nodes not participating in the path planning while the back-source path is dynamically planned for the CDN nodes, and conditions are provided for accelerating dynamic contents such as videos and the like by adopting the CDN network.

Description

Path planning method, CDN connection establishing method, device and storage medium

Technical Field

The present application relates to the field of network communication technologies, and in particular, to a path planning method, a CDN connection establishment method, a device, and a storage medium.

Background

A Content Delivery Network (CDN) is an intelligent virtual Network built on the basis of an existing Network, and a user can obtain required Content nearby by using edge servers (i.e., CDN nodes) deployed in various places, so that the response speed of user access is increased. In addition, in the CDN network, the CDN nodes adopt a multi-level cache structure, and when a content required by a user is not cached in a CDN node at a lower level, a corresponding content is requested to a CDN node at an upper level thereof until a source station (Origin Server) and returned to the user, thereby improving a user access success rate.

With the development of video applications such as live broadcasting and on-demand broadcasting, a large amount of video contents gradually become one of the most bandwidth-consuming transmission forms on the internet, and the problems of long buffer time, slow start time, frequent interruption and the like exist, so that the watching experience of a user is seriously influenced. In order to improve the viewing experience of users, service providers such as video on demand and live broadcast will rely more on the CDN network to speed up the distribution of video content.

However, in the video applications such as live broadcast and on-demand, the user groups are dispersed, which breaks through the hierarchical boundary between CDN nodes in the CDN network, and a static back-to-source path pre-configured according to the hierarchical relationship between the original CDN nodes is not applicable, so how to plan the back-to-source path for the CDN nodes is the problem that is primarily solved when the CDN network is used to accelerate dynamic content such as video.

Disclosure of Invention

Various aspects of the present application provide a path planning method, a CDN connection establishment method, a device, and a storage medium, so as to dynamically plan a back-source path for a CDN node, improve a path planning success rate, and provide conditions for accelerating dynamic content such as a video using a CDN network.

The embodiment of the application provides a path planning method, which comprises the following steps: receiving a path planning request initiated by a first CDN node in a CDN network, wherein the path planning request is used for requesting to plan a back-to-source path from the first CDN node to a source station; if the CDN node participating in the path planning in the CDN network does not have a regulation to plan or cannot plan a back-to-source path meeting the conditions, selecting a second CDN node from pre-configured standby CDN nodes not participating in the path planning; taking the second CDN node as a relay CDN node between the first CDN node and the source station to obtain a back-to-source path from the first CDN node to the source station; and sending the information of the back source path to the first CDN node so that the first CDN node establishes connection with the source station through the second CDN node.

The embodiment of the present application further provides a CDN connection establishment method, which is applicable to a first CDN node in a CDN network, and includes: according to the received resource request, sending a path planning request to a routing device to request to plan a back-to-source path from a first CDN node to a source station; receiving information of a back-source path returned by the routing equipment, wherein the information of the back-source path comprises information of a second CDN node, and the second CDN node is a relay CDN node which is configured in advance by the routing equipment and is selected for a first CDN node and a source station from standby CDN nodes which do not participate in path planning; and establishing connection with the source station through the second CDN node according to the information of the second CDN node so as to request resource content corresponding to the resource request from the source station.

An embodiment of the present application further provides a routing device, including: a memory and a processor; a memory for storing a computer program; a processor coupled with the memory for executing the computer program for: receiving a path planning request initiated by a first CDN node in a CDN network, wherein the path planning request is used for requesting to plan a back-to-source path from the first CDN node to a source station; if the CDN node participating in the path planning in the CDN network does not have a regulation to plan or cannot plan a back-to-source path meeting the conditions, selecting a second CDN node from pre-configured standby CDN nodes not participating in the path planning; taking the second CDN node as a relay CDN node between the first CDN node and the source station to obtain a back-to-source path from the first CDN node to the source station; and sending the information of the back source path to the first CDN node so that the first CDN node establishes connection with the source station through the second CDN node.

The embodiment of the present application further provides a CDN node, which may be implemented as a first CDN node in a CDN network, where the CDN node includes: a memory and a processor; a memory for storing a computer program; a processor coupled with the memory for executing the computer program for: according to the received resource request, sending a path planning request to a routing device to request to plan a back-to-source path from a first CDN node to a source station; receiving information of a back-source path returned by the routing equipment, wherein the information of the back-source path comprises information of a second CDN node, and the second CDN node is a relay CDN node which is configured in advance by the routing equipment and is selected for a first CDN node and a source station from standby CDN nodes which do not participate in path planning; and establishing connection with the source station through the second CDN node according to the information of the second CDN node so as to request resource content corresponding to the resource request from the source station.

Embodiments of the present application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to implement the steps in the methods provided by the embodiments of the present application.

In the embodiment of the application, the CDN network includes not only CDN nodes participating in path planning but also backup CDN nodes not participating in path planning; when a path planning request is received, firstly, dynamic path planning is carried out based on CDN nodes participating in path planning in a CDN network, and under the condition that the path planning fails, appropriate backup CDN nodes are selected from backup CDN nodes not participating in the path planning, the backup CDN nodes are used as relay CDN nodes between the CDN nodes requesting the path planning and a source station so as to obtain a back-source path, the back-source path can be successfully planned based on the backup CDN nodes not participating in the path planning while the back-source path is dynamically planned for the CDN nodes, and conditions are provided for accelerating dynamic contents such as videos and the like by adopting the CDN network.

Drawings

The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:

fig. 1 is a schematic structural diagram of a CDN network system according to an exemplary embodiment of the present disclosure;

fig. 2a is a schematic diagram of a back-source path and a state existing between partial nodes in a CDN network system according to an exemplary embodiment of the present disclosure;

fig. 2b is a schematic diagram of a back-to-source path and a state existing between partial nodes after being established based on a backup CDN node according to an exemplary embodiment of the present disclosure;

fig. 2c is a schematic diagram of a process of establishing a connection between a CDN node and a source station according to an exemplary embodiment of the present disclosure;

fig. 3 is a schematic architecture diagram of a video live broadcast system based on a CDN network according to an exemplary embodiment of the present disclosure;

fig. 4a is a schematic flowchart of a path planning method according to an exemplary embodiment of the present application;

fig. 4b is a schematic flowchart of a CDN connection establishing method according to an exemplary embodiment of the present disclosure;

fig. 5a is a schematic structural diagram of a path planning apparatus according to an exemplary embodiment of the present application;

FIG. 5b is a schematic structural diagram of a routing device according to an exemplary embodiment of the present application;

fig. 6a is a schematic structural diagram of a CDN connection establishing apparatus according to an exemplary embodiment of the present disclosure;

fig. 6b is a schematic structural diagram of a CDN node according to an exemplary embodiment of the present disclosure.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the technical solutions of the present application will be described in detail and completely with reference to the following specific embodiments of the present application and the accompanying drawings. It should be apparent that the described embodiments are only some of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The embodiment of the application provides a CDN network system, which can be regarded as a distributed cache system, can provide distributed cache services for its clients, and can enable a user to obtain required content nearby through functions of load balancing, content distribution, scheduling, and the like, thereby reducing network congestion and improving user access response speed and hit rate. In the CDN network system provided in the embodiment of the present application, a client may be a provider of resource content, for example, a live video service provider, a video on demand service provider, and other service providers that provide dynamic resource content, and these service providers may accelerate distribution of the dynamic resource content provided by the service providers by using the CDN network system. Certainly, the CDN network system of this embodiment may also accelerate the distribution of static resource content, such as large files or software. In the following embodiments of the present application, a description is given by taking a CDN network as an example to accelerate distribution of dynamic resource content.

As shown in fig. 1, a CDN network system 100 provided in the embodiment of the present application includes: a source station 101, a plurality of CDN nodes 102, a Domain Name System (DNS) server 103, a load balancing device 104, and a routing device 105.

The source station 101 is a core of the CND network system 100, and is a source of resource content provided by a service provider in the CND network system 100, that is, the resource content provided by the service provider is uploaded to the source station 101 first, and all resource content on the CDN node 102 comes from the source station 101; in physical implementation, the source station 101 may be any computer device with computing, storage, and communication capabilities, such as a conventional server, a cloud server, an array of servers, and so on. For example, the following steps are carried out: if the service provider is a live video service provider, the source station 101 may be a server accessed by a live broadcast end and is responsible for storing live video content of the live broadcast end; if the facilitator is a video-on-demand facilitator, the source station 101 may be a server accessed by the on-demand facilitator responsible for storing on-demand content provided by the on-demand facilitator. In the CDN network system 100, the number of source stations 101 may be one or multiple, and is illustrated as one example in fig. 1. In addition, in the CDN network system 100, the source station 101 may be dynamically changed, that is, the source station 101 may be dynamically generated when needed or dynamically disappeared when not needed.

The DNS server 103 is responsible for providing domain name resolution services for users. In this embodiment, a demander of resource content is simply referred to as a user, and a resource request initiated by the user first reaches the DNS server 103; the DNS server 103 performs DNS analysis on the resource request of the user and returns the IP address of the load balancing equipment 104 to the user; a user initiates a resource request to the load balancing device 104; the load balancing device 104 selects an appropriate CDN node 102 for the user to provide service for the user, and returns an IP address of the CDN node 102 to the user, so that the user initiates a resource request to the CDN node 102.

Optionally, as shown in fig. 1, the DNS server 103 of this embodiment includes a local DNS server 103a and a root DNS server 103 b; the local DNS server 103a is a DNS server of the user side; root DNS server 103b is a DNS server dedicated to the CDN network. Specifically, a domain name resolution request initiated by a user reaches the local DNS server 103a first, and the local DNS server 103a will hand the domain name resolution right to the root DNS server 103 b; root DNS server 103b returns the IP address of load balancing device 104 to the user.

The basis for the load balancing device 104 to select the CDN node 102 for the user includes, but is not limited to, the following: according to the IP address of the user, selecting a CDN node 102 which is closest or close to the user to provide service for the user; according to the content name carried in the URL in the resource request, selecting a CDN node 102 with the resource content required by the user to provide service for the user; querying the load condition of each CDN node 102, and selecting a CDN node 102 with service capability to provide service for a user; and so on.

The CDN nodes 102 are distributed in different locations, and may be any computer device with computing, communication and storage capabilities, such as edge servers, terminal devices, edge computing devices, and the like deployed in various places. These CDN nodes 102 are closer to the user and are responsible for responding to resource requests initiated by the user and providing the user with the required resource content. After receiving a resource request initiated by a user, the CDN node 102 may determine whether the local area has resource content requested by the user; if the CDN node 102 locally has the resource content requested by the user, directly returning the resource content required by the user to the user; if the CDN node 102 does not locally have the resource content requested by the user, the CDN node 102 needs to obtain the resource content from another CDN node 102 or the source station 101 by using a back-to-source mechanism and return the resource content to the user.

In this embodiment, multiple paths may exist between CDN nodes 102 and between CDN node 102 and source station 101. Then, when CDN node 102 executes the back-to-source mechanism, a path planning problem is involved. In the embodiment of the present application, path planning refers to a process of finding a back-to-source path between a CDN node 102 that originates a request and a source station 101. In addition, when the CDN network system 100 is applied to dynamic resource scenes such as live video and video on demand, which CDN node 102 may become the closest CDN node to the user due to the dispersion of the user population in these scenes, the hierarchical relationship between the CDN nodes 102 cannot be set in advance according to the distance between the CDN nodes 102 and the user, and even if the hierarchical relationship between the CDN nodes 102 is configured in advance, the hierarchical boundary between the CDN nodes 102 is broken due to the dispersion of the user population. That is, when the CDN network system 100 is applied to a dynamic resource scenario such as live video or video on demand, the CDN nodes 102 are actually in a peer-to-peer relationship and are not limited by a hierarchical relationship, and a back-to-source path between the CDN node 102 and the source station 101 dynamically changes due to the dispersion of user groups. Accordingly, the back-to-source path between the CDN node 102 and the source station 101 cannot be determined through the hierarchical relationship between the CDN nodes 102.

In this embodiment, the CDN network system 100 is additionally provided with the routing device 105, and the routing device 105 performs dynamic path planning for the CDN node 102 according to the path planning request of the CDN node 102. For any CDN node 102, if it receives a resource request initiated by a user and finds that there is no resource content requested by the user locally, it may initiate a path planning request to the routing device 105 to request the routing device 105 to plan a back-to-source path to the source station 101 for the routing device, so as to obtain the resource content from other CDN nodes or the source station 101 on the back-to-source path and return the resource content to the user. For convenience of description and distinction, in the embodiment of the present application, a CDN node in the CDN network system 100 that receives a resource request initiated by a user is referred to as an originating CDN node. In addition to this, in the CDN network system 100, there may be some actual access paths between some origin CDN nodes 102 and the origin station 101, and these access paths may also include other CDN nodes. In actual use, the relay CDN node may be disconnected from its next hop due to factors such as a link failure and a network failure, and at this time, the relay CDN node may also initiate a path planning request to the routing device 105 to request the routing device 105 to plan a back-to-source path to the source station 101, so that the starting CDN node can continue to obtain resource content requested by the user from the relay CDN node or the source station on the back-to-source path and return the resource content to the user. For convenience of description and distinction, a CDN node that initiates a path planning request is denoted as a first CDN node. In this embodiment, the first CDN node may be an originating CDN node, or may be a relay CDN node on an access path actually existing between the originating CDN node and the source station.

In this embodiment, the routing device 105 may receive a path planning request initiated by the first CDN node, where the path planning request includes identification information of the first CDN node and information pointing to the source station. The identification information of the first CDN node may be an IP address, an MAC address, and the like of the first CDN node. Taking a live application as an example, the information pointing to the source station may include information such as a URL of a live end, a name of a live stream, and an application name, and these information may point to a unique source station. In this embodiment, the routing device 105 may obtain the network topology relationship of the CDN network system 100, obtain information such as the state of each CDN node, and perform path planning for the first CDN node based on the information. Further, the routing device 105 may perform path planning for the first CDN node by using a certain path planning policy. The path planning strategies that the routing device 105 can adopt include, but are not limited to: a shortest path planning strategy, an optimal path planning strategy, a global path planning strategy and the like. In this embodiment, the routing device 105 may dynamically plan a back-to-source path from the first CDN node to the corresponding source station according to the path planning request of the first CDN node. In some cases, routing device 105 may successfully plan a back-to-source path from the first CDN node to the source station, and the back-to-source path may be multiple. However, in some application scenarios, the routing device 105 may not be able to successfully plan a back-to-source path from the first CDN node to the source station.

As shown in fig. 2a, a back-to-source path exists between partial nodes in the CDN network system 100, in this example, nodes E1-E3 represent 3 originating CDN nodes, nodes R4-R8 represent 5 relaying CDN nodes, and node S9 represents a source station; in this example, the originating CDN nodes E1-E3 each request resource content from the source station S9. In fig. 2a, nodes E1-E3 can initiate a path planning request to routing device 105, and routing device 105 successfully plans a back-source path for nodes E1-E3 as shown in fig. 2 a: there are 4 back-source paths between node E1 and node S9: e1- > R4- > R7- > R8- > S9, E1- > R4- > R5- > R8- > S9, E1- > E2- > R5- > R8- > S9 and E1- > E2- > R6- > R8- > S9; there are 2 back-to-source paths between node E2 and node S9: e2- > R5- > R8- > S9, E2- > R6- > R8- > S9; there are 1 back-to-source paths between node E3 and node S9: e3- > R6- > R8- > S9.

In this embodiment, a back-to-back hop relationship exists between adjacent nodes on a back-to-source path, that is, one node is a previous hop of another node, and the other node is a next hop of the node; in this embodiment, according to the path trend of the back-to-source path, the up-down-hop relationship between the nodes may be referred to as a parent-child relationship, the previous-hop node in the up-down-hop relationship may be referred to as a child node, and the next-hop node may be referred to as a parent node. For example, for the provenance path E1- > R4- > R7- > R8- > S9, node E1 is a child node of node R4, node R4 is a parent node of node E1, while node R4 is also a child node of node R7; node R7 is the parent of node R4 but is a child of node R8, and so on.

In practical applications, assuming that the connection between the node R8 and the node S9 is broken, the node R8 may initiate a path planning request to the routing device 105 to request the routing device 105 to plan a path for it. In the example shown in fig. 2a, since CDN nodes connected to the node R8, that is, the nodes R6-R7 are all child nodes of the node R8, and the child nodes of the node R8 are CDN nodes that use the node R8 as a next hop node in a back source path, in this case, a loop is formed between the nodes, and the routing device 105 cannot successfully plan a back source path from the node R8 to the node S9.

As can be seen from the example shown in fig. 2a, in the process of planning the back source path for the first CDN node, the routing device 105 may analyze whether CDN nodes connected to the first CDN node are all child nodes of the first CDN node; and if the CDN nodes connected with the first CDN node are all child nodes of the first CDN node and the first CDN node forms a loop, determining that a back-to-source path from the first CDN node to the source station is drawn out without regulation. Optionally, in some cases, CDN nodes connected to the first CDN node may not be all child nodes of the first CDN node, and only a part of the CDN nodes may be selected to participate in the path planning of the first CDN node in the path planning process, that is, a part of the CDN nodes connected to the first CDN node may be selected as next hop nodes of the first part of CDN nodes, and if the next hop nodes planned for the first CDN node are all child nodes of the first CDN node, in this case, the first CDN node may also form a loop, and it may also be determined that a back-to-source path from the first CDN node to the source station is planned without a rule.

If the routing device 105 does not regularly plan a back-to-source path from the first CDN node to the source station, the first CDN node will not be able to provide the required resource content for the user, which may cause interruption or hitching of the user service, and reduce the service experience of the user on the CDN network system 100. In addition to this, there may be some situations where there may be certain requirements on the back source path due to application requirements. For example, the client requires that the hop count of the back-source path is less than or equal to the set hop count threshold, so as to ensure the back-source delay. For another example, a CDN node in the CDN network is heavily loaded, is in charge of delivering an important data stream, or has a fault temporarily, and the back-to-source path is required to avoid the CDN node, that is, the back-to-source path cannot include a designated CDN node. In view of this, although the routing device 105 may plan a back-to-source path from the first CDN node to the source station, the planned back-to-source path does not necessarily meet the condition; if the planned back-to-source path from the first CDN node to the source station does not meet the condition, the first CDN node cannot provide the required resource content for the user through the back-to-source path, which may also cause interruption or suspension of user service, thereby reducing the service experience of the user on the CDN network system 100.

In order to ensure the service quality of the CDN network system 100, in this embodiment, the CDN nodes 102 are divided into two types, one type is a conventional CDN node that normally participates in path planning, and the other type is a backup CDN node that does not participate in path planning, as shown in fig. 1. Which CDN nodes may become backup CDN nodes that do not participate in path planning may be preconfigured. Optionally, the backup CDN node may also be dynamically adjusted. The backup CDN nodes that do not participate in the path planning may serve as bottom-of-pocket nodes, and these backup CDN nodes may serve as relay CDN nodes between the first CDN node and the source station under the condition that the routing device 105 does not regularly plan a back-source path from the first CDN node to the source station or does not regularly plan a back-source path that meets the conditions, so as to connect the first CDN node and the source station together to form the back-source path.

For the routing device 105, when receiving a path planning request initiated by a first CDN node, the routing device may dynamically perform path planning for the first CDN node based on a conventional CDN node that can participate in the path planning in the CDN network, specifically, dynamically perform path planning for the first CDN node based on a topological relation between the conventional CDN nodes and other information; if a back-source path from the first CDN node to the source station is successfully planned based on the topological relation among the conventional CDN nodes and other information, or a back-source path meeting the conditions from the first CDN node to the source station is successfully planned based on the topological relation among the conventional CDN nodes and other information, returning the information of the planned back-source path to the first CDN node so that the first CDN node establishes connection with the source station based on the information of the back-source path. Further, if a back-source path from the first CDN node to the source station is drawn based on a topological relation between conventional CDN nodes and other information without rules, or a back-source path that meets conditions is drawn from the first CDN node to the source station without rules, a backup CDN node may be selected from backup CDN nodes that are configured in advance and do not participate in path planning, and for convenience of description, the selected backup CDN node is referred to as a second CDN node; further, a second CDN node is used as a relay CDN node between the first CDN node and the source station to obtain a source return path from the first CDN node to the source station; and finally, sending the information of the back source path to the first CDN node so that the first CDN node establishes connection with the source station through the second CDN node. Optionally, if the hop count of the back-to-source path from the first CDN node to the source station, which is planned based on the topological relation between CDN nodes participating in path planning in the CDN network and other information, is greater than a set hop count threshold, the back-to-source path does not meet the condition; or, if the back-to-source path planned from the first CDN node to the source station based on the topological relation between CDN nodes participating in path planning in the CDN network and other information includes the specified CDN node, the back-to-source path also does not meet the condition. Of course, what kind of return path is eligible can be flexibly set according to the application requirement, which is not limited, and the foregoing is only an example.

Continuing with the example shown in fig. 2a, in the case of finding that a back-to-source path from node R8 to node S9 is ruleless planned due to a loop occurring at node R8, routing device 105 selects a second CDN node from backup CDN nodes B1-Bn that do not participate in the path planning, taking backup CDN node Bn as an example, taking backup CDN node Bn as a relay node between node R8 and source station S9, after node R8 is connected to backup node Bn, CDN backup CDN node Bn is directly connected to source station S9, and there are no other intermediate nodes between node R8 and source station S9, as shown in fig. 2B.

When a second CDN node is selected from the backup CDN nodes, connectivity of the backup CDN nodes needs to be considered, and a backup CDN node that is simultaneously communicated with the first CDN node and the source station needs to be selected as the second CDN node. The communication here mainly means having physical connection relationship, and means having physical basis for establishing logical connection; the connectivity of the backup CDN node may be measured by the number of other nodes or source stations to which the backup CDN node is physically connected; the greater the number of other nodes or source stations to which the backup CDN node is physically connected, the greater the number of the backup CDN nodes.

Further optionally, if a plurality of backup CDN nodes are simultaneously connected to the first CDN node and the source station, one of the backup CDN nodes may be randomly selected as the second CDN node; alternatively, one of the plurality of backup CDN nodes may be selected as the second CDN node according to at least one parameter of operator compatibility, a location, and network performance of the CDN node. The operator compatibility of the CDN node refers to which mobile communication operators the CDN node supports, for example, whether the CDN node supports only a certain mobile communication operator, or supports multiple mobile communication operators and which mobile communication operators are specifically supported; the greater the number of mobile communication operators supported by the CDN node, the better the operator compatibility of the CDN node. The network performance of the CDN node may be embodied by at least one of a network delay, a packet loss rate, an available bandwidth, a current load amount, and the like of the CDN node. Generally, the smaller the network delay, the lower the packet loss rate, the more available bandwidth, and the smaller the current load, the better the network performance of the CDN node is.

Optionally, when a plurality of standby CDN nodes are simultaneously communicated with the first CDN node and the source station, one of the plurality of standby CDN nodes with better operator compatibility may be selected as the second CDN node; or, one of the backup CDN nodes with better network performance may be selected as the second CDN node; or, one of the backup CDN nodes whose position is closest to the first CDN node may be selected as the second CDN node; or, the comprehensive scores of the multiple backup CDN nodes may also be calculated according to the operator compatibility, the network performance, and the positions of the multiple backup CDN nodes; selecting one of the backup CDN nodes with the highest comprehensive score as a second CDN node; and so on.

In the embodiment of the application, when the backup CDN nodes that do not participate in path planning are configured, the backup CDN nodes in different geographic areas may be guaranteed as much as possible according to the area coverage principle. One embodiment is: according to the regional coverage principle, CDN nodes located in different geographic regions are selected from existing CDN nodes in a CDN network to serve as standby CDN nodes. The other implementation mode is as follows: and deploying new CDN nodes in different geographic areas covered by the CDN network as standby CDN nodes according to an area coverage principle. Of course, a combination of the two approaches may also be implemented.

Further, for each geographic area, when a backup CDN node is selected from existing CDN nodes in the geographic area, the backup CDN node may be selected from CDN nodes located in the geographic area according to connectivity of the CDN nodes. Optionally, the CDN node with the best or better connectivity may be preferentially selected as the backup CDN node. Further optionally, when selecting the backup CDN node, in addition to considering the connectivity of the CDN node, the backup CDN node may also be combined with other attributes of the CDN node, for example, at least one of operator compatibility, location, and network performance of the CDN node may also be combined at the same time. In a specific embodiment, for each geographic area, according to the connectivity of CDN nodes, a candidate CDN node that meets the connectivity requirement may be selected from CDN nodes located in the geographic area; further, if there are a plurality of candidate CDN nodes, a spare CDN node is selected from the candidate CDN nodes according to at least one parameter of operator compatibility, a location, and network performance of the CDN node.

In practical applications, the number, deployment location, and/or connectivity relationship of CDN nodes in a CDN network may vary. In view of this, in some embodiments of the present application, the spare CDN node may be dynamically adjusted according to the number of CDN nodes in the CDN network, the deployment location, and/or change information of the connectivity relationship, so that a CDN node that meets requirements better can be selected as the spare CDN node. For example, when a CDN node with better connectivity is newly added to the CDN network, the newly added CDN node may be used as a standby CDN node, or the newly added CDN node may replace an existing standby CDN node. For another example, when a CDN node in the CDN network is deployed in the geographic area D1 and is selected as a backup CDN node in the geographic area D1, when the deployment location of the CDN node changes, for example, the CDN node is handed over from the geographic area D1 to another geographic area D2, the CDN node is no longer suitable as a backup CDN node in the geographic area D1 and needs to be deleted from the backup CDN node in the geographic area D1.

Further, in order to facilitate management, maintenance and dynamic adjustment of the standby CDN node, a visual configuration interface may be provided for a user (e.g., a relevant administrator), where the configuration interface is used for the user to manage, maintain and dynamically adjust the standby CDN node. For example, through the configuration interface, a user may configure a standby CDN node, delete the standby CDN node, enter relevant information of the standby CDN node, and the like, and may also dynamically configure an adjustment policy of the standby CDN node, so that the standby CDN node can be dynamically adjusted according to the adjustment policy. Optionally, the configuration interface may include a policy configuration item, and the user may add at least one adjustment policy by triggering the policy configuration item. The adjustment strategy can be that when a CDN node is newly added in the CDN network, a standby CDN node is added; or, when a CDN node whose connectivity meets a set connectivity condition occurs in the CDN network, adding the CDN node as a standby CDN node; or, when a CDN node with better connectivity appears in a certain geographic area, replacing one with the worst connectivity among existing backup CDN nodes in the geographic area with the CDN node, and so on. Based on this, a configuration interface can be displayed for a user, a configuration operation of the user on the configuration interface is responded, an adjustment strategy of the spare CDN node is obtained, and then the spare CDN node is dynamically adjusted according to the adjustment strategy and by combining the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

In this embodiment, the CDN network includes not only CDN nodes participating in path planning, but also backup CDN nodes not participating in path planning; when a path planning request is received, firstly, dynamic path planning is carried out based on CDN nodes participating in path planning in a CDN network, and under the condition that the path planning fails, appropriate backup CDN nodes are selected from backup CDN nodes not participating in the path planning, the backup CDN nodes are used as relay CDN nodes between the CDN nodes requesting the path planning and a source station so as to obtain a back-source path, the back-source path can be successfully planned based on the backup CDN nodes not participating in the path planning while the back-source path is dynamically planned for the CDN nodes, and conditions are provided for accelerating dynamic contents such as videos and the like by adopting the CDN network.

After planning a back-source path to the source station for the first CDN node, the routing device 105 may further send information of the back-source path to the first CDN node, so that the first CDN node establishes a connection with the source station based on the back-source path. The information of the back-to-source path comprises information of a first CDN node, a source station and a relay CDN node from the first CDN node to the source station, and a jump relation among the first CDN node, the relay CDN node and the source station.

For the first CDN node, the information of the back-to-source path returned by the routing device 105 may be received, and according to the information of the back-to-source path, the next hop and the information of the next hop of the first CDN node are determined, and further, the path information after the next hop may be determined; on one hand, connection is established with the next hop according to the information of the next hop of the first CDN node, and on the other hand, the path information after the next hop is sent to the next hop so that the next hop continues to establish connection with the next hop based on the path information after the next hop until the next hop reaches a relay CDN node or a source station on a back-to-source path, wherein the relay CDN node or the source station has resource content required by a user. In fig. 2a, a procedure of establishing CDN connection between the node E1 and the node S9 and 4 back-source paths between the node E1 and the node S9 is taken as an example for explanation. As shown in fig. 2c, after the node E1 initiates a path planning request to the routing device 105, the routing device 105 dynamically plans 4 back-to-source paths for the node E1 and returns information of the 4 back-to-source paths to the node E1; assuming that the node E1 selects the back source path E1- > R4- > R7- > R8- > S9, and establishes the CDN connection with the node S9 according to the information of the back source path, the process is: the node E1 establishes connection with the node R4, and sends the path information R7- > R8- > S9 behind the node R4 to the node R4; the node R4 establishes connection with the node R7, and sends the path information R8- > S9 behind the node R7 to the node R8; the node R8 establishes a connection with the node S9. Here, in this example, the routing device 105 provides all the information of the 4 back-to-source paths dynamically planned for the node E1 to the node E1, but the invention is not limited thereto. For example, the selection device 105 may also use a path selection policy, select one or part of the back-source paths from the planned back-source paths, and return information of the selected back-source path to the node E1. Accordingly, in this example, the node E1 selects to establish the CDN connection with the source station according to the information of one of the back-to-source paths when acquiring the information of the multiple back-to-source paths, but is not limited to this. For example, the node E1 may also select to establish two or more CDN connections with the source station according to information of two or more back-to-source paths, or may even select to establish multiple CDN connections with the source station according to information of received multiple back-to-source paths. When two or more CDN connections exist between the node E1 and the source station, one of the CDN connections may be selected for resource content transmission, and the remaining CDN connections are reserved; alternatively, two or more CDN connections may be used at the same time to transmit the resource content at the same time, which is not limited.

It should be noted that, in this embodiment, the back-to-source path received by the first CDN node may be planned by the routing device 105 based on a conventional CDN node participating in path planning, or may be planned by the routing device 105 based on a backup CDN node not participating in path planning. If the back-to-source path received by the first CDN node is planned for the routing device 105 based on a backup CDN node that does not participate in path planning, the relay CDN node on the back-to-source path is a second CDN node selected by the routing device 105 from the backup CDN nodes, and information of the back-to-source path includes information of the second CDN node. For the first CDN node, a connection may be established with the source station through the second CDN node according to information of the second CDN node, so as to request resource content corresponding to the resource request from the source station. Further, the information of the back-to-source path further includes a jump relationship indicating that the second CDN node is a next hop of the first CDN node and is a previous hop of the source station. Based on this, the process of establishing a connection with the source station via the second CDN node according to the information of the second CDN node includes: and establishing connection with a second CDN node according to the jump relation and the information of the second CDN node, and sending the information of a source station which is used as a next jump of the second CDN node to the second CDN node so as to establish connection between the second CDN node and the source station. The connection establishment procedure is similar to that shown in fig. 2c, except that the relay CDN nodes and their number are different.

Further optionally, in this embodiment, the backup CDN node may be specially marked to distinguish it from the regular CDN node. For example, a "backup" flag may be added to the identifier of the backup CDN node, and the implementation of the "backup" flag is not limited, and may be any flag information that can be recognized by a user or a network administrator. Based on this, the first CDN node may output information of the back-source path to a user or a network administrator or other related personnel, in addition to establishing the CDN connection with the source station according to the information of the back-source path returned by the routing device 105. When the back-to-source path is planned by the routing device 105 based on a backup CDN node that does not participate in path planning, the information of the back-to-source path includes information of a second CDN node, where the information of the second CDN node includes a marker of the backup CDN node, and a user or a network administrator can know, through the marker, that the back-to-source path is established through the backup CDN node, instead of a conventional CDN node. Further, for a network administrator, it can be known that a loop occurs in the first CDN node according to the label of the exposed backup CDN node, and a loop solution is further adopted to solve the loop problem.

Fig. 3 is a schematic architecture diagram of a video live broadcast system based on a CDN network according to an exemplary embodiment of the present application. As shown in fig. 3, the system includes: a live terminal 301, a live service end 302, a viewing terminal 303, and a CDN network system 300.

In this embodiment, the implementation forms of the live terminal 301, the live service end 302, and the viewing terminal 303 are not limited. For example, the live terminal 301 may be, but is not limited to: smart phones, tablet computers, desktop computers, smart televisions, and the like. For example, the live server 302 may be a conventional server, a cloud server, or a server array. For example, the viewing terminal 303 may be, but is not limited to: smart phones, tablet computers, desktop computers, smart televisions, and the like.

In this embodiment, the live terminal 301 and the live service end 302 and the viewing terminal 303 and the live service end 302 are in communication connection. The live terminal 301 is mainly responsible for recording live video and providing the live video to the viewing terminal 303. In this embodiment, the content of the live video is not limited, and may be, for example, remote education content, live shopping content, live video conference, live entertainment content, or the like, which is not limited. Regardless of the content of the live video, while the live video belongs to a streaming media, that is, the live terminal 301 transmits the live video on line in real time, the watching terminal 303 needs to continuously receive and watch or listen to the transmitted live video. The live broadcast server 302 is a key device for ensuring that the live broadcast terminal 301 successfully provides live broadcast video to the viewing terminal 303 as a core system in the live broadcast system of this embodiment. The live broadcast server 302 is located between the live broadcast terminal 301 and the viewing terminal 303, and is mainly responsible for managing a live broadcast room, processing instant messages between the live broadcast terminal and the viewing terminal, performing real-time video processing, controlling and managing a live broadcast room microphone connecting process, and the like. The viewing terminal 303 is equipped with a live broadcast application, and can respond to an operation of a user viewing a live broadcast video through the live broadcast application, display a live broadcast interface, acquire the live broadcast video, and play the live broadcast video on the live broadcast interface.

In this embodiment, the CDN network system 300 is used to deliver the live video to the viewing terminal 303, so as to improve the efficiency of the viewing terminal 303 acquiring the live video. As shown in fig. 3, the CDN network system 300 at least includes: source station 304, CDN node 305, routing device 306, and DNS server 307. In this embodiment, the live terminal 301 uploads the recorded live video to the source station 304; the source station 304 is responsible for storing live video recorded by the live terminal 301. When a user wishes to watch a live video, a live application on the watching terminal 303 may be opened to enter an application interface (e.g., a home page), and an entry of the live video that the user wishes to watch (e.g., a live icon, a live URL, a live moving picture, or the like) is selected on the application interface; the watching terminal 303 responds to the trigger of the user to the entry of the live video, and initiates a DSN resolution request to the DNS server 307, where the resolution request includes a URL corresponding to the live video; the DNS server 307 redirects the viewing terminal 303 to a regular CDN node 305 close to the viewing terminal 303 by analyzing the URL, and marks as a first CDN node; the viewing terminal 303 initiates a resource request to the first CDN node.

In an initial stage, the first CDN node does not locally have a live video provided by the live terminal 301, so after receiving the resource request, the first CDN node initiates a path planning request to the routing device 306 to request to plan a back-to-source path from the first CDN node to the source station 304. The routing device 306 first plans a back-to-source path from the first CDN node to the source station 304 in the conventional CDN nodes by using a certain path planning policy based on a topological relationship between the first CDN node and the conventional CDN nodes that can participate in path planning. The resource request includes a unique identifier pointing to the live video, which may be, for example, a live URL, a stream identifier, and an identifier of the live application.

If the back source path is successfully planned, sending information of the back source path to a first CDN node; the first CDN node establishes a connection with the source station 304 through at least one relay CDN node (the relay CDN node in this case is a conventional CDN node) according to the information of the back-to-source path, and acquires a live video provided by the live broadcast terminal 301 from the source station 304 based on the connection, where each relay CDN node on the back-to-source path and the first CDN node both locally cache the live video.

If the back-source path cannot be successfully planned based on the conventional CDN node, selecting a backup CDN node from the backup CDN nodes, marking the backup CDN node as a second CDN node, taking the second CDN node as a relay CDN node between the first CDN node and the source station 304, forming the back-source path between the first CDN node and the source station 304, and sending information of the back-source path to the first CDN node; the first CDN node establishes a connection with the source station 304 through at least one relay CDN node (the relay CDN node in this case is a conventional CDN node) according to the information of the back-to-source path, and acquires a live video provided by the live broadcast terminal 301 from the source station 304 based on the connection, where each relay CDN node on the back-to-source path and the first CDN node both locally cache the live video.

No matter what path planning is performed, the CDN node 305 in this embodiment may be used as a cache node, and when receiving a live video, the live video is locally cached. If other watching terminals 303 initiate a live broadcast request for requesting the same live broadcast video to the first CDN node in the following process, because the live broadcast video is locally cached in the first CDN node, the first CDN node can directly return the live broadcast video to other watching terminals 303 in the following process, so that the efficiency of the watching terminal 303 acquiring the live broadcast video can be improved, delay and blockage are reduced, watching fluency is improved, and watching experience of a user is improved. It should be noted that the CDN network system 300 of this embodiment may provide video acceleration service for multiple live broadcast terminals 301 at the same time, and each CDN node 305 may locally cache multiple video streams, which may be specifically distinguished by identifiers of the video streams.

Further, in the process that the CDN node 305 provides the live video to the viewing terminal 303 through the CDN connection with the source station 304, a situation that the CDN connection is disconnected may occur, and for the CDN node that the CDN connection is disconnected, the CDN node may also serve as a first CDN node to initiate a path planning request to the routing device 306, so as to request the routing device 306 to plan a return-to-source path to the source station 306 again for the CDN node, so that the live video can be continuously provided to the viewing terminal 303 from a disconnected point based on the new return-to-source path. For the routing device 306, the reason why the first CDN node initiates the path planning request does not need to be paid attention to, and a back-source path may be planned for the first CDN node by using the same path planning method on the basis of the conventional CDN node and the backup CDN node. In this embodiment, while the routing device 306 dynamically plans the back-source path for the CDN node, the back-source path can be guaranteed to be successfully planned based on the backup CDN node, which provides a condition for accelerating a live video using the CDN network.

Fig. 4a is a schematic flowchart of a path planning method according to an exemplary embodiment of the present disclosure. As shown in fig. 4a, the method comprises:

41a, receiving a path planning request initiated by a first CDN node in a CDN network, wherein the path planning request is used for requesting to plan a back-to-source path from the first CDN node to a source station;

42a, if a back-to-source path meeting the conditions cannot be planned or planned based on the CDN nodes participating in the path planning in the CDN network without regulations, selecting a second CDN node from pre-configured standby CDN nodes not participating in the path planning;

43a, taking the second CDN node as a relay CDN node between the first CDN node and the source station, and obtaining a back-to-source path from the first CDN node to the source station;

and 44a, sending the information of the back source path to the first CDN node so that the first CDN node establishes connection with the source station through the second CDN node.

In an optional embodiment, the first CDN node is an originating CDN node in the CDN network, or a relay CDN node on an access path actually existing between the originating CDN node and the source station; the starting CDN node is a CDN node that receives a resource request initiated by a user.

In an optional embodiment, the method provided by this implementation further includes: if the CDN nodes connected with the first CDN node are all child nodes of the first CDN node, determining that a back-to-source path from the first CDN node to the source station is drawn out without regulation; or if the next hop nodes planned for the first CDN node are all child nodes of the first CDN node, determining that a back-to-source path from the first CDN node to the source station is planned without regulations; the child node of the first CDN node is a CDN node that uses the first CDN node as a next hop node in the back-to-source path.

In an optional embodiment, if the hop count of a back-to-source path planned based on a CDN node participating in path planning in the CDN network is greater than a set hop count threshold, the back-to-source path does not meet a condition; or if a back-source path planned based on the CDN nodes participating in the path planning in the CDN network includes a designated CDN node, the back-source path does not meet the condition.

In an optional embodiment, the pre-configuring a standby CDN node that does not participate in path planning includes: according to the regional coverage principle, CDN nodes in different geographic regions are selected from existing CDN nodes in a CDN network to serve as standby CDN nodes; and/or deploying new CDN nodes in different geographic areas covered by the CDN network as standby CDN nodes according to the area coverage principle.

In an optional embodiment, selecting CDN nodes located in different geographic areas from existing CDN nodes in a CDN network as backup CDN nodes includes: and aiming at each geographic area, selecting a standby CDN node from CDN nodes in the geographic area according to the connectivity of the CDN nodes.

In an optional embodiment, selecting a backup CDN node from CDN nodes located in the geographic area according to connectivity of the CDN nodes includes: according to the connectivity of the CDN nodes, selecting candidate CDN nodes meeting the connectivity requirements from CDN nodes located in the geographic area; and selecting a standby CDN node from the candidate CDN nodes according to at least one parameter of operator compatibility, position and network performance of the CDN node.

In an optional embodiment, the method further comprises: and dynamically adjusting the spare CDN nodes according to the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

Further optionally, dynamically adjusting the spare CDN nodes according to the number of CDN nodes in the CDN network, the deployment location, and/or change information of the connectivity relationship, includes: displaying a configuration interface for a user to configure an adjustment strategy of the standby CDN node; responding to the configuration operation on the configuration interface, and acquiring an adjustment strategy of the standby CDN node; and according to the adjustment strategy, dynamically adjusting the spare CDN nodes by combining the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

In an optional embodiment, selecting the second CDN node from pre-configured backup CDN nodes that do not participate in the path planning includes: and selecting a standby CDN node which is simultaneously communicated with the first CDN node and the source station from the standby CDN nodes as a second CDN node.

In an optional embodiment, selecting, from the backup CDN nodes, a backup CDN node that is simultaneously in communication with the first CDN node and the source station, as the second CDN node includes: if a plurality of standby CDN nodes are simultaneously communicated with the first CDN node and the source station, one of the standby CDN nodes is selected as a second CDN node according to at least one parameter of operator compatibility, position and network performance of the CDN nodes.

Fig. 4b is a schematic flowchart of a CDN connection establishment method according to an exemplary embodiment of the present disclosure, where the method is applied to a first CDN node in a CDN network. As shown in fig. 4b, the method comprises:

41b, sending a path planning request to the routing device according to the received resource request so as to request to plan a back-source path from the first CDN node to the source station;

42b, receiving information of a back-source path returned by the routing device, wherein the information of the back-source path comprises information of a second CDN node, and the second CDN node is a relay CDN node which is configured in advance by the routing device and is selected for a first CDN node and a source station from standby CDN nodes which do not participate in path planning;

and 43b, establishing connection with the source station through the second CDN node according to the information of the second CDN node so as to request the source station for resource content corresponding to the resource request.

In an optional embodiment, before sending the path planning request to the routing device, the method provided in this embodiment further includes: and determining that the first CDN node does not locally have resource content corresponding to the resource request according to the received resource request, and the first CDN node and the source station are in an unconnected state.

In an optional embodiment, the information of the back source path further includes: indicating that the second CDN node is the next hop of the first CDN node and is the jump relation of the last hop of the source station; establishing connection with the source station through the second CDN node according to the information of the second CDN node, comprising: and establishing connection with the second CDN node according to the jump relation and the information of the second CDN node, and sending the information of the source station to the second CDN node so as to establish connection between the second CDN node and the source station.

In the embodiment of the application, the CDN node may request the routing device to dynamically plan a back-to-source path to the source station by sending a path planning request to the routing device; the route selection equipment can ensure that a back-source path can be successfully planned for the CDN node based on a backup CDN node which does not participate in path planning; after the CDN node acquires the complete back-to-source path information, on one hand, connection is established with the adjacent next hop, on the other hand, the subsequent path information is sequentially issued, so that the next hop can continue to establish connection with the next hop according to the subsequent path information until the establishment of the CDN connection is completed, the CDN node along the way can be ensured to be accurately established according to the back-to-source path, and conditions are provided for accelerating dynamic contents such as videos by adopting a CDN network.

It should be noted that the execution subjects of the steps of the methods provided in the above embodiments may be the same device, or different devices may be used as the execution subjects of the methods. For example, the execution subjects of steps 41a to 43a may be device a; for another example, the execution subject of

steps

41a and 42a may be device a, and the execution subject of step 43a may be device B; and so on.

In addition, in some of the flows described in the above embodiments and the drawings, a plurality of operations are included in a specific order, but it should be clearly understood that the operations may be executed out of the order presented herein or in parallel, and the sequence numbers of the operations, such as 41a, 42a, etc., are merely used for distinguishing various operations, and the sequence numbers themselves do not represent any execution order. Additionally, the flows may include more or fewer operations, and the operations may be performed sequentially or in parallel. It should be noted that, the descriptions of "first", "second", etc. in this document are used for distinguishing different messages, devices, modules, etc., and do not represent a sequential order, nor limit the types of "first" and "second" to be different.

Fig. 5a is a schematic structural diagram of a path planning apparatus according to an exemplary embodiment of the present application. As shown in fig. 5a, the apparatus comprises: a receiving module 51a, a path planning module 52a, an obtaining module 53a and a sending module 54 a.

A receiving module 51a, configured to receive a path planning request initiated by a first CDN node in a CDN network, where the path planning request is used to request to plan a back-to-source path from the first CDN node to a source station;

the path planning module 52a is configured to select a second CDN node from pre-configured backup CDN nodes that do not participate in path planning if a CDN node participating in path planning in the CDN network does not regularly plan or cannot plan a back-to-source path that meets a condition;

an obtaining module 53a, configured to use the second CDN node as a relay CDN node between the first CDN node and the source station, to obtain a back-to-source path from the first CDN node to the source station;

the sending module 54a is configured to send information of the back-to-source path to the first CDN node, so that the first CDN node establishes a connection with the source station through the second CDN node.

In an optional embodiment, the path planning module 52a is further configured to: under the condition that CDN nodes connected with the first CDN node are all child nodes of the first CDN node, a source returning path from the first CDN node to a source station is determined to be drawn out without regulation; or determining that a back-source path from the first CDN node to the source station is drawn without regulation under the condition that the next hop nodes drawn for the first CDN node are all child nodes of the first CDN node; the child node of the first CDN node is a CDN node that uses the first CDN node as a next hop node in the back-to-source path.

In an optional embodiment, the apparatus further comprises: and the configuration module is used for configuring standby CDN nodes which do not participate in path planning in advance. Specifically, the configuration module is configured to: according to the regional coverage principle, CDN nodes in different geographic regions are selected from existing CDN nodes in a CDN network to serve as standby CDN nodes; and/or deploying new CDN nodes in different geographic areas covered by the CDN network as standby CDN nodes according to the area coverage principle.

Further optionally, when the configuration module selects CDN nodes located in different geographic areas from existing CDN nodes in the CDN network as the standby CDN node, the configuration module is specifically configured to: and aiming at each geographic area, selecting a standby CDN node from CDN nodes in the geographic area according to the connectivity of the CDN nodes.

Further optionally, when the configuration module selects a standby CDN node from CDN nodes located in the geographic area according to connectivity of the CDN nodes, the configuration module is specifically configured to: according to the connectivity of the CDN nodes, selecting candidate CDN nodes meeting the connectivity requirements from CDN nodes located in the geographic area; and selecting a standby CDN node from the candidate CDN nodes according to at least one parameter of operator compatibility, position and network performance of the CDN node.

In an optional embodiment, the configuration module is further configured to: and dynamically adjusting the spare CDN nodes according to the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

Further optionally, the configuration module is specifically configured to, when dynamically adjusting the standby CDN node: displaying a configuration interface for a user to configure an adjustment strategy of the standby CDN node; responding to the configuration operation on the configuration interface, and acquiring an adjustment strategy of the standby CDN node; and according to the adjustment strategy, dynamically adjusting the spare CDN nodes by combining the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

In an optional embodiment, when the configuration module selects the second CDN node from the preconfigured backup CDN nodes that do not participate in the path planning, the configuration module is specifically configured to: and selecting a standby CDN node which is simultaneously communicated with the first CDN node and the source station from the standby CDN nodes as a second CDN node.

Further optionally, the configuration module selects, from the spare CDN nodes, a spare CDN node that is simultaneously communicated with the first CDN node and the source station, and when the spare CDN node is used as the second CDN node, is specifically configured to: if a plurality of standby CDN nodes are simultaneously communicated with the first CDN node and the source station, one of the standby CDN nodes is selected as a second CDN node according to at least one parameter of operator compatibility, position and network performance of the CDN nodes.

Having described the internal functions and structure of the path planner, as shown in fig. 5b, in practice, the path planner can be implemented as a routing device, comprising: memory 54, processor 55, and communications component 56.

A memory 54 for storing computer programs and can be configured to store other various data to support operations on the routing device. Examples of such data include instructions for any application or method operating on the routing device, contact data, phonebook data, messages, pictures, videos, and so forth.

The memory 54 may be implemented by any type or combination of volatile or non-volatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disks.

A processor 55 coupled to the memory 54 for executing computer programs in the memory 54 for: receiving, by the communication component 56, a path planning request initiated by a first CDN node in the CDN network, where the path planning request is used to request planning of a back-to-source path from the first CDN node to the source station; if the CDN node participating in the path planning in the CDN network does not have a regulation to plan or cannot plan a back-to-source path meeting the conditions, selecting a second CDN node from pre-configured standby CDN nodes not participating in the path planning; taking the second CDN node as a relay CDN node between the first CDN node and the source station to obtain a back-to-source path from the first CDN node to the source station; the information of the back-to-source path is sent to the first CDN node through the communication component 56, so that the first CDN node establishes a connection with the source station through the second CDN node.

In an alternative embodiment, processor 55 is further configured to: if the CDN nodes connected with the first CDN node are all child nodes of the first CDN node, determining that a back-to-source path from the first CDN node to the source station is drawn out without regulation; or if the next hop nodes planned for the first CDN node are all child nodes of the first CDN node, determining that a back-to-source path from the first CDN node to the source station is planned without regulations; the child node of the first CDN node is a CDN node that uses the first CDN node as a next hop node in the back-to-source path.

In an optional embodiment, when the standby CDN node not participating in the path planning is configured in advance, the processor 55 is specifically configured to: according to the regional coverage principle, CDN nodes in different geographic regions are selected from existing CDN nodes in a CDN network to serve as standby CDN nodes; and/or deploying new CDN nodes in different geographic areas covered by the CDN network as standby CDN nodes according to the area coverage principle.

Further optionally, when the processor 55 selects CDN nodes located in different geographic areas from CDN nodes existing in the CDN network as backup CDN nodes, the processor is specifically configured to: and aiming at each geographic area, selecting a standby CDN node from CDN nodes in the geographic area according to the connectivity of the CDN nodes.

Further optionally, when the processor 55 selects a spare CDN node from CDN nodes located in the geographic area according to connectivity of the CDN node, the spare CDN node is specifically configured to: according to the connectivity of the CDN nodes, selecting candidate CDN nodes meeting the connectivity requirements from CDN nodes located in the geographic area; and selecting a standby CDN node from the candidate CDN nodes according to at least one parameter of operator compatibility, position and network performance of the CDN node.

In an alternative embodiment, processor 55 is further configured to: and dynamically adjusting the spare CDN nodes according to the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

Further optionally, when dynamically adjusting the standby CDN node, the processor 55 is specifically configured to: displaying a configuration interface for a user to configure an adjustment strategy of the standby CDN node; responding to the configuration operation on the configuration interface, and acquiring an adjustment strategy of the standby CDN node; and according to the adjustment strategy, dynamically adjusting the spare CDN nodes by combining the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

In an optional embodiment, when the processor 55 selects the second CDN node from the pre-configured backup CDN nodes that do not participate in the path planning, the processor is specifically configured to: and selecting a standby CDN node which is simultaneously communicated with the first CDN node and the source station from the standby CDN nodes as a second CDN node.

Further optionally, the processor 55 selects a standby CDN node that is simultaneously communicated with the first CDN node and the source station from the standby CDN nodes, and when the standby CDN node is used as the second CDN node, the processor is specifically configured to: if a plurality of standby CDN nodes are simultaneously communicated with the first CDN node and the source station, one of the standby CDN nodes is selected as a second CDN node according to at least one parameter of operator compatibility, position and network performance of the CDN nodes.

Further, as shown in fig. 5b, the routing device further comprises: display 57, power supply components 58, audio components 59, and the like. Only some of the components are schematically shown in fig. 5b, and the routing device is not meant to comprise only the components shown in fig. 5 b.

Accordingly, the present application also provides a computer readable storage medium storing a computer program, and the computer program can implement the steps that can be executed by the routing device in the embodiment of the method shown in fig. 4a when being executed.

Fig. 6a is a schematic structural diagram of a CDN connection establishing apparatus according to an exemplary embodiment of the present disclosure. As shown in fig. 6a, the apparatus comprises: a sending module 61a, a receiving module 62a and a connection establishing module 63 a.

The sending module 61a is configured to send a path planning request to the routing device according to the received resource request, so as to request to plan a back-to-source path from the first CDN node to the source station;

the receiving module 62a is configured to receive information of a back-to-source path returned by the routing device, where the information of the back-to-source path includes information of a second CDN node, and the second CDN node is a relay CDN node selected for the first CDN node and the source station from backup CDN nodes that do not participate in path planning and are configured in advance by the routing device;

the connection establishing module 63a is configured to establish a connection with the source station through the second CDN node according to the information of the second CDN node, so as to request resource content corresponding to the resource request from the source station.

In an optional embodiment, the apparatus further comprises: and determining a module. The determining module is configured to send a path planning request to the routing device at the sending module 61a, and determine that the first CDN node does not locally have resource content corresponding to the resource request according to the received resource request, and the first CDN node and the source station are in an unconnected state.

In an optional embodiment, the information of the back source path further includes: and indicating that the second CDN node is the next hop of the first CDN node and is the jump relation of the last hop of the source station. Based on this, when establishing a connection with the source station via the second CDN node according to the information of the second CDN node, the connection establishing module 63a is specifically configured to: and establishing connection with the second CDN node according to the jump relation and the information of the second CDN node, and sending the information of the source station to the second CDN node so as to establish connection between the second CDN node and the source station.

The internal functions and structures of the CDN connection establishing apparatus are described above, and as shown in fig. 6b, in practice, the CDN connection establishing apparatus may be implemented as a first CDN node in a CDN network, and includes: memory 64, processor 65, and communication component 66.

Memory 64 for storing computer programs and may be configured to store other various data to support operations on CDN nodes. Examples of such data include instructions for any application or method operating on the CDN node, contact data, phonebook data, messages, pictures, videos, and so forth.

The memory 64 may be implemented by any type or combination of volatile or non-volatile memory devices such as Static Random Access Memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic or optical disks.

A processor 65, coupled to the memory 64, for executing computer programs in the memory 64 for: according to the received resource request, sending a path planning request to a routing device to request to plan a back-to-source path from a first CDN node to a source station; receiving, by the communication component 66, information of a back-to-source path returned by the routing device, where the information of the back-to-source path includes information of a second CDN node, and the second CDN node is a relay CDN node selected for the first CDN node and the source station from backup CDN nodes that do not participate in path planning and are configured in advance by the routing device; and establishing connection with the source station through the second CDN node according to the information of the second CDN node so as to request resource content corresponding to the resource request from the source station.

In an alternative embodiment, the processor 65 is further configured to, before sending the path planning request to the routing device: and determining that the first CDN node does not locally have resource content corresponding to the resource request according to the received resource request, and the first CDN node and the source station are in an unconnected state.

In an optional embodiment, the information of the back source path further includes: indicating that the second CDN node is the next hop of the first CDN node and is the jump relation of the last hop of the source station; when establishing a connection with the source station via the second CDN node according to the information of the second CDN node, the processor 65 is specifically configured to: and establishing connection with the second CDN node according to the jump relation and the information of the second CDN node, and sending the information of the source station to the second CDN node so as to establish connection between the second CDN node and the source station.

Further, as shown in fig. 6b, the first CDN node further includes: display 67, power supply 68, audio 69, and the like. Only a part of the components is schematically shown in fig. 6b, and it is not meant that the routing device comprises only the components shown in fig. 6 b.

Accordingly, the present application further provides a computer readable storage medium storing a computer program, where the computer program is capable of implementing the steps that can be executed by the first CDN node in the method embodiment shown in fig. 4b when executed.

The communication components of fig. 5b and 6b described above are configured to facilitate communication between the device in which the communication component is located and other devices in a wired or wireless manner. The device where the communication component is located can access a wireless network based on a communication standard, such as a WiFi, a 2G, 3G, 4G/LTE, 5G and other mobile communication networks, or a combination thereof. In an exemplary embodiment, the communication component receives a broadcast signal or broadcast related information from an external broadcast management system via a broadcast channel. In one exemplary embodiment, the communication component further includes a Near Field Communication (NFC) module to facilitate short-range communications. For example, the NFC module may be implemented based on Radio Frequency Identification (RFID) technology, infrared data association (IrDA) technology, Ultra Wideband (UWB) technology, Bluetooth (BT) technology, and other technologies.

The displays in fig. 5b and 6b described above include screens, which may include a Liquid Crystal Display (LCD) and a Touch Panel (TP). If the screen includes a touch panel, the screen may be implemented as a touch screen to receive an input signal from a user. The touch panel includes one or more touch sensors to sense touch, slide, and gestures on the touch panel. The touch sensor may not only sense the boundary of a touch or slide action, but also detect the duration and pressure associated with the touch or slide operation.

The power supply components of fig. 5b and 6b described above provide power to the various components of the device in which the power supply components are located. The power components may include a power management system, one or more power supplies, and other components associated with generating, managing, and distributing power for the device in which the power component is located.

The audio components of fig. 5b and 6b described above may be configured to output and/or input audio signals. For example, the audio component includes a Microphone (MIC) configured to receive an external audio signal when the device in which the audio component is located is in an operational mode, such as a call mode, a recording mode, and a voice recognition mode. The received audio signal may further be stored in a memory or transmitted via a communication component. In some embodiments, the audio assembly further comprises a speaker for outputting audio signals.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

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

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The above description is only an example of the present application and is not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A method of path planning, comprising:

receiving a path planning request initiated by a first CDN node in a CDN network, wherein the path planning request is used for requesting to plan a back-to-source path from the first CDN node to a source station;

if a back-to-source path meeting the conditions cannot be planned or planned based on the fact that CDN nodes participating in path planning in the CDN network are not regulated, selecting a second CDN node from pre-configured standby CDN nodes not participating in path planning;

taking the second CDN node as a relay CDN node between the first CDN node and the source station to obtain a source return path from the first CDN node to the source station;

and sending the information of the back-source path to the first CDN node so that the first CDN node establishes connection with the source station through the second CDN node.

2. The method of claim 1, wherein the first CDN node is an originating CDN node in a CDN network, or a relay CDN node on an access path that actually exists between the originating CDN node and a source station; the starting CDN node is a CDN node which receives a resource request initiated by a user.

3. The method of claim 1, further comprising:

if the CDN nodes connected with the first CDN node are all child nodes of the first CDN node, determining that a back-to-source path from the first CDN node to the source station is drawn out without regulation;

or

If the next hop nodes planned for the first CDN node are all child nodes of the first CDN node, determining that a back source path from the first CDN node to the source station is planned without regulations;

the child node of the first CDN node is a CDN node that uses the first CDN node as a next hop node in a back-to-source path.

4. The method of claim 1,

if the hop count of a back-source path planned by the CDN node participating in path planning in the CDN network is greater than a set hop count threshold value, the back-source path does not meet the condition;

if a back-source path planned based on the CDN nodes participating in path planning in the CDN network contains the designated CDN node, the back-source path does not meet the condition.

5. The method of claim 1, wherein pre-configuring a backup CDN node that does not participate in path planning comprises:

according to the regional coverage principle, CDN nodes in different geographic regions are selected from existing CDN nodes in a CDN network to serve as standby CDN nodes;

and/or

And deploying new CDN nodes in different geographic areas covered by the CDN network as standby CDN nodes according to an area coverage principle.

6. The method of claim 5, wherein selecting CDN nodes located in different geographic regions from existing CDN nodes in the CDN network as backup CDN nodes comprises:

and aiming at each geographic area, selecting a standby CDN node from CDN nodes in the geographic area according to the connectivity of the CDN nodes.

7. The method of claim 6, wherein selecting a backup CDN node from CDN nodes located in the geographic region according to CDN node connectivity comprises:

according to the connectivity of the CDN nodes, selecting candidate CDN nodes meeting the connectivity requirements from CDN nodes located in the geographic area;

and selecting a spare CDN node from the candidate CDN nodes according to at least one parameter of operator compatibility, position and network performance of the CDN node.

8. The method of any one of claims 5-7, further comprising:

and dynamically adjusting the spare CDN nodes according to the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

9. The method of claim 8, wherein dynamically adjusting the backup CDN nodes according to the number of CDN nodes in the CDN network, a deployment location, and/or change information of connectivity comprises:

displaying a configuration interface for a user to configure an adjustment strategy of the standby CDN node;

responding to the configuration operation on the configuration interface, and acquiring an adjustment strategy of the standby CDN node;

and according to the adjustment strategy, dynamically adjusting the spare CDN nodes by combining the number of CDN nodes in the CDN network, the deployment position and/or the change information of the communication relation.

10. The method of any of claims 1-7, wherein selecting the second CDN node from pre-configured backup CDN nodes that do not participate in path planning comprises:

and selecting a standby CDN node which is simultaneously communicated with the first CDN node and the source station from the standby CDN nodes as a second CDN node.

11. The method of claim 10, wherein selecting a backup CDN node from the backup CDN nodes that is in communication with both the first CDN node and the source station as a second CDN node comprises:

if a plurality of standby CDN nodes are simultaneously communicated with the first CDN node and the source station, one of the standby CDN nodes is selected as a second CDN node according to at least one parameter of operator compatibility, position and network performance of the CDN nodes.

12. A CDN connection establishment method is suitable for a first CDN node in a CDN network, and is characterized by comprising the following steps:

according to the received resource request, sending a path planning request to a routing device to request to plan a back-to-source path from a first CDN node to a source station;

receiving information of a back-to-source path returned by the routing device, wherein the information of the back-to-source path includes information of a second CDN node, and the second CDN node is a relay CDN node which is selected for the first CDN node and the source station from spare CDN nodes which do not participate in path planning and are configured in advance by the routing device;

and according to the information of the second CDN node, establishing connection with the source station through the second CDN node so as to request the source station for resource content corresponding to the resource request.

13. The method of claim 12, further comprising, prior to sending the path planning request to the routing device:

according to the received resource request, it is determined that the first CDN node does not locally have resource content corresponding to the resource request, and the first CDN node and the source station are in an unconnected state.

14. The method of claim 12 or 13, wherein the first CDN node is an originating CDN node in a CDN network or a relay CDN node on an access path actually existing between the originating CDN node and a source station; the starting CDN node is a CDN node which receives a resource request initiated by a user.

15. The method according to claim 12 or 13, wherein the information of the back-source path further comprises: indicating that the second CDN node is a next hop of the first CDN node and is a jump relation of a previous hop of the source station;

establishing a connection with the source station through the second CDN node according to the information of the second CDN node, including:

and establishing connection with the second CDN node according to the jump relation and the information of the second CDN node, and sending the information of the source station to the second CDN node so that the second CDN node can establish connection with the source station.

16. A routing device, comprising: a memory and a processor;

the memory for storing a computer program;

the processor, coupled with the memory, to execute the computer program to:

17. A CDN node can be implemented as a first CDN node in a CDN network, and is characterized by comprising: a memory and a processor;

the memory for storing a computer program;

the processor, coupled with the memory, to execute the computer program to:

18. A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, causes the processor to carry out the steps of the method according to any one of claims 1 to 15.