CN114157343A - Working method of CDN network system based on satellite communication - Google Patents

Working method of CDN network system based on satellite communication Download PDF

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Publication number
CN114157343A
CN114157343A CN202111465909.0A CN202111465909A CN114157343A CN 114157343 A CN114157343 A CN 114157343A CN 202111465909 A CN202111465909 A CN 202111465909A CN 114157343 A CN114157343 A CN 114157343A
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China
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resource
user
remote
request
server
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CN202111465909.0A
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杨永杰
路易
肖李鹏
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Nantong Research Institute for Advanced Communication Technologies Co Ltd
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Nantong Research Institute for Advanced Communication Technologies Co Ltd
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/14Relay systems
    • H04B7/15Active relay systems
    • H04B7/185Space-based or airborne stations; Stations for satellite systems
    • H04B7/1851Systems using a satellite or space-based relay
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04BTRANSMISSION
    • H04B7/00Radio transmission systems, i.e. using radiation field
    • H04B7/14Relay systems
    • H04B7/15Active relay systems
    • H04B7/185Space-based or airborne stations; Stations for satellite systems
    • H04B7/1851Systems using a satellite or space-based relay
    • H04B7/18519Operations control, administration or maintenance
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L67/00Network arrangements or protocols for supporting network services or applications
    • H04L67/01Protocols
    • H04L67/06Protocols specially adapted for file transfer, e.g. file transfer protocol [FTP]

Abstract

The invention discloses a working method of a CDN network system based on satellite communication, which comprises the following specific steps: a remote user accesses a satellite communication system containing CDN service through access equipment; a remote user requests a resource service; after receiving the user request, the remote resource server checks whether the resource of the user request is contained; after receiving the request of the remote station server, the ground center server checks whether the ground center station server contains the requested resource; and the remote resource server receives the response of the ground central station, stores the data and responds to the user to complete one request of the user. On the premise of ensuring that a remote user can be interconnected and intercommunicated with the outside through a satellite link, the invention introduces the Internet content acceleration system and constructs a set of CDN network system suitable for satellite communication, so that the remote user does not need to obtain the same resource from a source station when requesting the same resource again, thereby achieving the purposes of caching for multiple times, saving satellite bandwidth resources, reducing operation cost and the like.

Description

Working method of CDN network system based on satellite communication
Technical Field
The invention relates to the technical field of communication, in particular to a working method of a CDN network system based on satellite communication.
Background
With the increasing development of the internet, the information requirements of the life and work entertainment of vast netizens are met by streaming media on-line audio-visual, network games, massive news information and the like; video sharing, blogs, forums and the like enable vast network names to participate in the prosperity of the whole internet content; the enterprise can see the benefit growth point of the internet application by ubiquitous network marketing means such as online shopping, network advertisements and the like. The popularity and usage of the internet is increasing, resulting in a continuous increase in the overall traffic outlets.
As an important result of modern communication technology, satellite communication is developed on the basis of ground microwave communication and space technology, and has the advantages of large communication coverage area, long communication distance, wide communication frequency band, large capacity and the like. However, satellite communication also has the disadvantages of prolonged transmission time, easy signal attenuation, large error rate, and short bandwidth resource, and if a user needs to download a large-flow file or experience streaming media service, the problems of slow loading, reduced access speed, easy error, and the like occur, which leads to reduced user experience.
A cdn (content Delivery network), which is an intelligent virtual network constructed on the basis of an existing network, and enables a user to obtain required content nearby by using resource servers deployed in various regions and through functional modules of load balancing, content Delivery, scheduling, and the like of a central platform, thereby reducing network congestion and improving the corresponding speed of user access and user experience.
Disclosure of Invention
The invention aims to provide a working method of a CDN network system based on satellite communication, which particularly leads a user to directly obtain request resources from a remote station resource server without obtaining the request resources from a source station through a satellite link by introducing an internet content acceleration technology into the satellite communication system, greatly improves the speed of re-accessing the same resource, reduces network time delay, provides user experience, saves satellite bandwidth resources and reduces satellite link pressure.
In order to achieve the purpose, the invention adopts the technical scheme that: the working method of the CDN network system based on satellite communication has the innovation points that the specific steps are as follows:
s1, the remote user accesses the satellite communication system containing CDN service through the access device;
s2, the remote user requests resource service;
s3, after receiving the user request, the remote resource server checks whether the resource contains the resource requested by the user; if yes, returning a user request resource completion request; if not, requesting user content from the ground central station through the satellite link;
s4, after receiving the request of the remote station server, the ground center server checks whether the ground center station server contains the requested resource; if yes, returning a remote resource server request resource completion request through the satellite link; if not, the resources are downloaded from the Internet and returned to the remote resource server through the satellite link, and simultaneously, the resource data are stored in the ground central station server by the central station in a file type;
s5, the remote resource server receives the response of the ground central station, stores the data and responds to the user to complete the primary request of the user; when the remote user subsequently requests the same resource again, the remote resource server can directly provide the request, so that the content acceleration effect is realized.
Furthermore, the remote user refers to a user who is in a middle and far sea or a remote mountain area and cannot receive a base station signal, and can only establish contact with the outside through satellite communication; the access device comprises a mobile phone, a tablet computer or a computer.
Further, in step S2, the remote user initiates a DNS resolution request for browsing a specific resource, and the request information is sent to the remote resource server in a port mirror image or a split bypass manner.
Further, after the remote resource server receives the request information in step S3, the redirection analysis control module of the system determines whether to provide service for the requested information according to the content of the user request and the system setting requirement, i.e. the white list; if the content data belongs to the white list range, the redirection analysis control module sends 302 a redirection data packet to the user, and guides the user to send an access request to the cache module again. After receiving the user request, the cache module sends the address of the cache server to the user if the local request resource is detected, and guides the user to directly access the cache resource server through the intranet to obtain the resource.
Further, the redirection analysis control module analyzes the monitored uplink access data of the remote user and redirects the user access request to the cache module.
Further, if the redirection analysis control module detects that the content data is not in the white list range, the cache acceleration service is not provided, and the request is directly directed to the resource source station, that is, the remote user directly obtains the required resource from the source station.
Further, the satellite link includes a transmission link composed of a remote transceiver station, an uplink, a satellite transponder, a downlink and a ground transceiver station.
Further, in step S4, the ground central station server receives the resource request information from the remote station, first queries whether there is a matching resource on the local cache server, and if there is a matching resource, returns the resource data to the remote resource server through the satellite link; if not, the resource data are directly downloaded from the source station through the Internet, stored on the local resource cache server in a file type mode, and then returned to the remote resource server through the satellite link.
Furthermore, when the resource requested by the remote user has a cache on the local resource server, the user can directly obtain the resource from the resource server.
The invention has the beneficial effects that:
compared with the existing satellite communication system, the invention innovatively introduces the CDN of the Internet content acceleration system and constructs a set of CDN network systems suitable for satellite communication on the premise of ensuring that the remote user can be interconnected and communicated with the outside through a satellite link, so that the remote user does not need to obtain from a source station when requesting the same resource again, thereby achieving the purposes of once caching and multiple utilization, saving satellite bandwidth resources, reducing operation cost and the like.
Drawings
FIG. 1 is a general flow chart of the present invention;
FIG. 2 is a flow chart of a remote user requesting resources in accordance with the present invention;
fig. 3 is a flow chart of the ground hub station responding to a resource request according to the present invention.
Detailed Description
The invention will be further described with reference to the accompanying drawings.
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and the detailed description. It should be understood that the detailed description and specific examples, while indicating the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.
Example 1
Referring to fig. 1, a working method of a CDN network system based on satellite communication includes the following specific steps:
s1, the remote user accesses the satellite communication system containing CDN service through the access device;
s2, the remote user requests resource service;
s3, after receiving the user request, the remote resource server checks whether the resource contains the resource requested by the user; if yes, returning a user request resource completion request; if not, requesting user content from the ground central station through the satellite link;
s4, after receiving the request of the remote station server, the ground center server checks whether the ground center station server contains the requested resource; if yes, returning a remote resource server request resource completion request through the satellite link; if not, the resources are downloaded from the Internet and returned to the remote resource server through the satellite link, and simultaneously, the resource data are stored in the ground central station server by the central station in a file type;
s5, the remote resource server receives the response of the ground central station, stores the data and responds to the user to complete the primary request of the user; when the remote user subsequently requests the same resource again, the remote resource server can directly provide the request, so that the content acceleration effect is realized.
In this embodiment, the remote user refers to a user who is in the middle and far seas or remote mountainous areas and cannot receive a base station signal, and can only establish contact with the outside through satellite communication; the access device comprises a mobile phone, a tablet computer or a computer.
In this embodiment, in step S2, the remote user initiates a DNS resolution request for browsing a specific resource, and request information is sent to the remote resource server in a port mirror image or a split-beam bypass manner.
In this embodiment, after the remote resource server receives the request information in step S3, the redirection analysis control module of the system determines whether to provide service for the requested information according to the content of the user request and the system setting requirement, i.e., the white list; if the content data belongs to the white list range, the redirection analysis control module sends 302 a redirection data packet to the user, and guides the user to send an access request to the cache module again. After receiving the user request, the cache module sends the address of the cache server to the user if the local request resource is detected, and guides the user to directly access the cache resource server through the intranet to obtain the resource.
In this embodiment, the redirection analysis control module analyzes the monitored uplink access data of the remote user, and redirects the user access request to the cache module.
In this embodiment, if the redirection analysis control module detects that the content data is not in the white list range, the cache acceleration service is not provided, and the request is directly directed to the resource source station, that is, the remote user directly obtains the required resource from the source station.
In this embodiment, the satellite link includes a transmission link composed of a remote transceiver station, an uplink, a satellite transponder, a downlink, and a ground transceiver station. The transmission link is mainly used for establishing contact between users in middle and far seas or remote mountainous areas and the outside to realize interconnection; the CDN central station service is deployed on a ground transceiver station server and used for returning source to download content resources and providing acceleration service; the CDN remote station server is deployed on the remote receiving and transmitting station server and used for providing cache acceleration service for remote users; the uplink and downlink and the satellite transponder are mainly used for building a satellite link, and the remote user establishes contact with the outside through the satellite link to realize interconnection.
In this embodiment, in step S4, the ground central station server receives the resource request information from the remote station, first queries whether there is a matching resource on the local cache server, and if there is a matching resource, returns the resource data to the remote resource server through the satellite link; if not, the resource data are directly downloaded from the source station through the Internet, stored on the local resource cache server in a file type mode, and then returned to the remote resource server through the satellite link.
In the embodiment, when the resource requested by the remote user is cached on the local resource server, the user can directly acquire the resource from the resource server, so that the satellite link bandwidth does not need to be occupied again to go to the source station to acquire the resource, the purposes of caching for multiple times and saving the satellite bandwidth are achieved, the time delay of the user for accessing the internet is shortened, and the user experience is improved.
Example 2
Referring to fig. 2, the working method of the CDN network system based on satellite communication according to the present invention includes the following steps:
remote users in the middle and far seas or remote mountainous areas access the satellite communication system through mobile phones, tablet computers and other electronic terminal devices and attempt to access related resources through a satellite network.
Resource information requested by a remote user is sent to a remote station resource server in a port mirror image or light splitting bypass mode, after a CDN service on the remote station resource server captures the request information of the user, a redirection analysis module of a system determines whether to provide acceleration service for the requested information according to the request content of the user and the white list setting of the system. If the request content is not contained in the white list, the request of the user is directly directed to the source station, and the remote user acquires related resources from the source station through the satellite link; if the requested content is contained in the white list, the redirection analysis module sends 302 a redirection packet to the user.
After receiving 302 the redirection data packet, the remote user resends an access request to the system cache module, after receiving the user request, the cache module checks whether the local cache data of the resource is contained, and if the local cache data of the resource is contained, the cache module sends the address of the cache server to the client to guide the remote user to directly access the cache resource server through the intranet, so as to obtain the required resource; and if not, sending the request information to the ground central station resource server through the satellite link.
Referring to fig. 3, the working method of the CDN network system based on satellite communication provided by the present invention includes the following steps:
after receiving a resource request of a remote user, a CDN service on a ground central station server checks whether a local server contains the requested resource.
If the request resource contains the corresponding request resource, the resource is sent to the remote station resource server through the satellite link and is returned to the remote user, and the user request is completed.
If the remote station resource server does not contain the corresponding request resource, the corresponding resource is downloaded back to the source through the Internet, the resource data is stored on the central station resource server according to the file type, and meanwhile, the resource is sent to the remote station resource server through the satellite link and is returned to the remote user, so that the user request is completed.
After the resource information request is completed according to the steps, if the remote user accesses the same resource again, the remote user can directly obtain the resource from the local server through the intranet without occupying the satellite resource to the source station again, so that the purposes of once caching and multiple utilization, satellite bandwidth resource saving, operation cost reduction and the like can be realized.
Example 4
When a remote user requests a certain resource for the first time, the CDN service requests the resource from a source station and stores cache files on a ground central station server and a remote resource server; when the remote user requests a certain resource again, the CDN service guides the user to directly obtain the resource from the local resource server in a redirection mode without occupying the satellite link bandwidth again to obtain the resource from the source station, so that the time delay of the user for accessing the Internet is shortened, the acceleration effect is realized, and the user experience is improved.
The above description is only for the purpose of illustrating the technical solutions of the present invention and not for the purpose of limiting the same, and other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention should be covered within the scope of the claims of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims (9)

1. A working method of a CDN network system based on satellite communication is characterized by comprising the following specific steps:
s1, the remote user accesses the satellite communication system containing CDN service through the access device;
s2, the remote user requests resource service;
s3, after receiving the user request, the remote resource server checks whether the resource contains the resource requested by the user; if yes, returning a user request resource completion request; if not, requesting user content from the ground central station through the satellite link;
s4, after receiving the request of the remote station server, the ground center server checks whether the ground center station server contains the requested resource; if yes, returning a remote resource server request resource completion request through the satellite link; if not, the resources are downloaded from the Internet and returned to the remote resource server through the satellite link, and simultaneously, the resource data are stored in the ground central station server by the central station in a file type;
s5, the remote resource server receives the response of the ground central station, stores the data and responds to the user to complete the primary request of the user; when the remote user subsequently requests the same resource again, the remote resource server can directly provide the request, so that the content acceleration effect is realized.
2. The method of claim 1, wherein the CDN network system based on satellite communication is configured to: the remote user refers to a user who is in a middle and far sea or a remote mountain area and cannot receive a base station signal, and can only establish contact with the outside through satellite communication; the access device comprises a mobile phone, a tablet computer or a computer.
3. The method of claim 1, wherein the CDN network system based on satellite communication is configured to: in step S2, the remote user initiates a DNS resolution request for browsing a specific resource, and the request information is sent to the remote resource server in a port mirror image or a split bypass manner.
4. The method of claim 1, wherein the CDN network system based on satellite communication is configured to: after the remote resource server receives the request information in step S3, the redirection analysis control module of the system determines whether to provide service for the requested information according to the content of the user request and the system setting requirement, i.e. the white list; if the content data belongs to the white list range, the redirection analysis control module sends 302 a redirection data packet to the user, and guides the user to send an access request to the cache module again. After receiving the user request, the cache module sends the address of the cache server to the user if the local request resource is detected, and guides the user to directly access the cache resource server through the intranet to obtain the resource.
5. The method of claim 4, wherein the CDN network system based on satellite communication is configured to: the redirection analysis control module analyzes the monitored uplink access data of the remote user and redirects the user access request to the cache module.
6. The method of claim 4, wherein the CDN network system based on satellite communication is configured to: and if the redirection analysis control module detects that the content data is not in the white list range, the cache acceleration service is not provided, and the request is directly directed to a resource source station, namely, a remote user directly obtains the required resource from the source station.
7. The method of claim 1, wherein the CDN network system based on satellite communication is configured to: the satellite link comprises a transmission link consisting of a remote transceiver station, an uplink, a satellite transponder, a downlink and a ground transceiver station.
8. The method of claim 1, wherein the CDN network system based on satellite communication is configured to: in step S4, the ground central station server receives the resource request information from the remote station, first queries whether there is a matching resource on the local cache server, and if there is a matching resource, returns the resource data to the remote resource server through the satellite link; if not, the resource data are directly downloaded from the source station through the Internet, stored on the local resource cache server in a file type mode, and then returned to the remote resource server through the satellite link.
9. The method of claim 1, wherein the CDN network system based on satellite communication is configured to: when the resource requested by the remote user has a cache on the local resource server, the user can directly acquire the resource from the resource server.
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