KR101160542B1 - System and method for contents delivery based on multiple Content Delivery Network providers, and content provider name server thereof - Google Patents

Abstract

The present invention relates to a content distribution system and method through a plurality of CDN providers, and to a content provider name server, wherein a client receives a page from a content server, parses it, and discovers a URL of an object included in the page to the content provider name server. When requesting the IP address of the server that will transfer the object, the content provider name server selects the CDN provider to provide the object among the plurality of CDN providers and delivers the domain name of the selected CDN provider to the local name server to replicate the CDN provider. It includes the process of receiving the object from the server, through which, no additional delay time occurs in the middle mile interval, it is possible to increase the reliability of the content transmission by eliminating the need for interoperation between CDN providers.

Description

System and method for contents delivery based on multiple Content Delivery Network providers, and content provider name server

The present invention relates to a content distribution system and method through a content delivery network (CDN) provider, and a content provider name server. In particular, a content provider name server in which a client requests an IP address of a server storing an object included in a page. A content distribution system through a plurality of CDN providers which selects a CDN provider to provide a corresponding object among a plurality of CDN providers and transmits the domain name of the selected CDN provider to a local name server on the client side so that the client receives the object; Method, and a content provider name server.

In general, the number of contents (eg, videos, music, files, etc.) that a content provider (CP) provides to a client is very large. There is a heavy load for a web server to provide some or all of these to each of the multiple clients one-to-one. This is because a web server is connected to a single Internet Service Provider (ISP), whereas clients requesting content exist in multiple ISPs.

Therefore, traffic between ISPs increases exponentially as the number of content providers and clients increases, and transmission delay and / or transmission failure rate due to traffic congestion increases. In the worst case, the web server may fail over.

The CDN (Content Delivery Network) has been introduced to overcome this problem. A CDN is a collection of content that is concentrated on a content provider's web server that is remote from clients, such as pictures, banners, video, or audio. Point-of-presence is stored in the host server which is widely distributed, and the client connects to the host server through the returned path by returning the path of the host server closest to the user when requested by the client. This service allows you to receive content. The host server is variously referred to as a cache server, a replication server, or a ghost server.

However, it would be expensive and time-consuming to install and operate a replica server that would allow a single CDN service provider to serve all regions of the world. To this end, content internetworking technology has been discussed.

Content interworking technology is a technology that enables CDN operators to interwork with each other, also referred to as 'content peering' technology. Content interworking technology is a technology used by a CDN provider when it cannot cover a global network with sufficient penetration depth and is a technology required to expand its content distribution area.

For details on content interoperability techniques, see Internet draft- "content internetworking architectural overview", "distribution requirements for content internetworking", "content distribution internetworking (CDI) AAA requirements" and RFC3570 "content distribution internetworking (CDI) scenarios", And standard documents.

Also, R. Buyya, AMK Pathan, J. Broberg, and Z. Tari, "A Case for Peering of Content Delivery Networks," IEEE Distributed Systems Online, Vol. . 7, No. 10, IEEE CS Press, Los Alamitos, CA, USA, October 2006, and discusses content interoperability technologies and systems that have been discussed from the past to the present.

The standard documents and references disclose the contents of CDN service providers in providing services to clients, and introduce a virtual organization model for redirection, distribution, and accounting. Is proposing.

According to these contents, previously discussed techniques are as follows. When a client in a specific region requests specific content to the content provider, the content request is redirected to the CDN provider contracted with the content provider, and the CDN provider selects a CDN provider that is geographically close to the client among other CDN providers that are interoperable with the content. Select this to redirect the content request and respond to the client's request.

This conventional method has the following problems.

Regardless of the location of the client requesting the content first, it is routed to the CDN provider contracted with the content provider, and then to the CDN provider closest to the client, thereby providing latency (RRT) in the middle mile section of the Internet. : Round Trip Time occurs.

Secondly, if the client's request is not properly responded during the interworking, the customer may have difficulty in identifying the responsibility for the inconvenience.

There is a need for a method for improving the above problems.

The present invention has been proposed to solve the above-mentioned problems, and the CDN provider to provide the corresponding object among the plurality of CDN providers in the content provider name server inquired the IP address of the server that stores the object contained in the page from the client The purpose of the present invention is to provide a content distribution system and method through a plurality of CDN providers, and to provide a content provider name server. have.

Content distribution method through a plurality of CDN operators of the present invention for achieving the above object, the storage step of receiving and storing the object contained in the page from the content server at least one copy server of the plurality of CDN operators, the content The content provider name server that receives the IP address query of the server that stores the object from the local name server on the client side that receives the page from the server, selects the object among the plurality of CDN providers by referring to the location of the client. A delivery step of selecting a CDN provider to be transmitted and transferring the domain name information of the selected CDN provider to the local name server, and receiving the IP address query of a replication server storing the object from the local name server in the domain name. The one or more replica servers in the corresponding operator name server The IP address of a particular replica server send the body via the local name server and a transmission step of transmitting to the client.

In the content distribution method through a plurality of CDN providers of the present invention, the delivering step, characterized in that the content provider name server refers to the location of the client using the IP address information of the client.

In the content distribution method through a plurality of CDN providers of the present invention, the delivering step, the content provider name server is one or more information of the service area information of the plurality of CDN providers and object information serviced by the plurality of CDN providers The CDN service provider for transmitting the object may be selected by referring to a global network map including a network map.

In the content distribution method through a plurality of CDN providers of the present invention, the delivering step, characterized in that the content provider name server delivers the CDN provider domain name information in the CNAME resource record to the local name server. .

In the content distribution method through a plurality of CDN providers of the present invention, the transmitting step, the local name server to query the IP address of the replication server with reference to the CDN provider domain name information included in the CNAME resource record It is characterized by.

In the content distribution method through a plurality of CDN providers of the present invention, the transmitting step, the data traffic information of the at least one replica server in the provider name server, local proximity information between the at least one replica server and the client and the at least one The IP address of the specific replication server may be transmitted to the local name server in consideration of one or more pieces of object information stored by each of the replication servers.

Content distribution system through a plurality of CDN operators of the present invention for achieving the above object, a content server for providing a page and the objects contained in the page, a plurality of CDN for receiving and storing the object from the content server Receiving an IP address query of a server storing the object from at least one copy server of a provider and a local name server of a client receiving the page from the content server, the plurality of CDN providers by referring to the location of the client A content provider name server for selecting a CDN provider to which the object is to be transmitted and transferring the domain name information of the selected CDN provider to the local name server, and an IP address query of a replication server storing the object from the local name server. When received, transmit the object among the one or more replication servers The IP address of a particular replica server via the local name server and a provider name server corresponding to the domain name to be transmitted to the client.

In the content distribution system through a plurality of CDN providers of the present invention, the content provider name server is characterized by referring to the location of the client using the IP address information of the client.

In a content distribution system through a plurality of CDN providers of the present invention, the content provider name server may include a global network including at least one of service area information of the plurality of CDN providers and object information serviced by the plurality of CDN providers. The CDN operator for transmitting the object is selected by referring to the work map.

In the content distribution system through a plurality of CDN providers of the present invention, the content provider name server is characterized by including the CDN provider domain name information in the CNAME resource record to deliver to the local name server.

In the content distribution system through a plurality of CDN providers of the present invention, the local name server is characterized by querying the IP address of the replication server by referring to the CDN provider domain name information included in the CNAME resource record. .

In the content distribution system through a plurality of CDN providers of the present invention, the service provider name server, the data traffic information of the one or more replication server, local proximity information between the one or more replication server and the client and each of the one or more replication server The IP address of the specific replica server is transmitted to the local name server in consideration of one or more pieces of stored object information.

Content provider name server of the present invention for achieving the above object, the transmission and reception unit for transmitting and receiving data, the service area information of a plurality of CDN operators, and stores the information of one or more of the object information serviced by the plurality of CDN providers Receiving an IP address query of a server storing the object through the transceiver unit from a local name server on the client side receiving a page from a global network map database and a content server, the location of the client and the global network map data are received. And a control unit which selects a CDN provider to transmit the object from among the plurality of CDN providers by referring to the information stored in the base, and delivers the domain name information of the selected CDN providers to the local name server.

In the content provider name server of the present invention, the controller refers to the location of the client using IP address information of the client.

In the content provider name server of the present invention, the global network map database further includes IP address information corresponding to service areas of the plurality of CDN service providers.

In the content provider name server of the present invention, the controller selects a CDN provider to which the object is to be transmitted by further referring to the IP address information.

In the content provider name server of the present invention, the control unit includes the CDN service provider domain name information in a CNAME resource record and transmits the same to the local name server.

According to the present invention, the content provider's name server selects the most appropriate CDN provider to respond to the client's object request and routes the corresponding content request, so that no additional delay time occurs in the middle mile section, This eliminates the need for interworking, thereby increasing the reliability of content delivery.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the detailed description of known functions and configurations incorporated herein will be omitted when it may unnecessarily obscure the subject matter of the present invention. In addition, the same reference numerals are used for parts having similar functions and functions throughout the drawings.

1 is a block diagram of a content distribution system through a plurality of CDN operators according to an embodiment of the present invention. Referring to FIG. 1, the content distribution system according to the present embodiment includes a client 110, a local name server 120, a replication server 130, a business name server 140, a content provider name server 150, and a content server ( 160 and network 170.

The client 110 refers to equipment such as a computer that receives information from a server connected to the network 170. The client 110 includes a browser and a resolver. When a URL (Uniform Resource Locater) for requesting specific content is input to the browser of the client 110, a resolver connected to the browser accesses a local name server 120 that is registered in advance. It converts the name into an Internet Protocol (IP) address of the content server 160 providing the corresponding content.

In the present invention, when the client 110 receives a page from the content server 160 using the IP address of the content server 160, the client 110 parses the page and stores the object using the URL of the object included in the page. The local name server 120 is queried for the server's IP address. Then, when receiving the IP address of the server storing the object included in the page from the local name server 120, it receives the object using this.

The local name server 120 refers to a DNS (Domain Name Server) for converting a domain name into an IP address, and converts a symbolic name into a numeric address used by a machine to inform the name server. It is a kind. The local name server 120 receiving the domain name information of the content server 160 from the resolver of the client 110 receives the IP (Internet Protocol) address of the content server 160 corresponding to the domain name. Return).

In addition, when the local name server 120 receives the domain name information of the CDN provider to respond to the object request of the client 110 from the content provider name server 150 which is a name server of a content provider (CP), Requests the IP address of the replication server 130 to provide the object to the provider name server 140, which is the name server of the CDN provider side using the domain name, and delivers it to the client 110.

The replication server 130 is also called a cache server, for example, and stores a copy of an object stored and managed by the content server 160 to quickly provide a content request from the client 110. It plays a role.

The business name server 140 has IP address information of the replication server 130. When the business name server 140 receives an IP address of the replication server 130 to transmit an object from the local name server 120, the business name server 140 selects a replication server 130 suitable for responding to the object request, and selects the corresponding replication server 130. The IP address is transmitted to the client 110 via the local name server 120.

In this case, the selection of the replication server 130 includes data traffic information of one or more replication servers including the replication server 130, local proximity information between the client 110 and one or more replication servers including the replication server 130, and the replication server ( One or more replication servers, including 130) are made in consideration of one or more pieces of object information stored in each.

The content server 160 stores a web page provided by a content provider and an embedded object included in the page, and transmits the web page to the client 110 when a content request is received from the client 110. A server that plays a role.

The content provider of the present invention makes a contract with a plurality of CDN providers and transmits and stores an object included in a page from the content server 160 to a replication server held by each CDN provider. This is to allow a quick response through the replication server 130 when the client 110 requests a specific object.

The content provider name server 150 is a type of name server having domain name information of a plurality of CDN providers contracted with a content provider. When the content provider name server 150 receives an IP address of the content server 160 storing the page from the local name server 120, the content provider name server 150 returns the corresponding IP address. In addition, when the content provider name server 150 receives the IP address of the server that stores the object included in the page from the local name server 120, the content provider name server 150 refers to the location of the client 110. The CDN provider suitable for transmitting the object is selected at 110 and the domain name information of the selected CDN provider is transmitted to the local name server 120.

In this case, the content provider name server 150 checks the location of the client 110 in consideration of, for example, the IP address of the client 110. In addition, a specific CDN provider is selected to provide an object to the client 110 by referring to a global network map including service area information of a plurality of CDN providers contracted with a content provider. For example, the global network map may store contents of service area information of each CDN service provider, content information stored in the replication server 130 of each CDN service provider, and the like.

The content provider name server 150 may transmit the CDN provider domain name information to the local name server 120 by using, for example, a CNAME (Canonical NAME) method. CNAME stands for the DNS database record of the alias representing the host name.

The network 170 transmits data and exchanges information between the client 110, the local name server 120, the replication server 130, the operator name server 140, the content provider name server 150, and the content server 160. Means a data communication network.

The configuration and operation of the content provider name server 150 according to an embodiment of the present invention will be described in more detail with reference to FIG. 2.

2 is a block diagram of the content provider name server 150 shown in FIG. 1 according to an embodiment of the present invention. 1 and 2, the content provider name server 150 according to the present embodiment includes a transceiver 210, a controller 220, and a global network map database 230.

The transceiver 210 has an interface for data transmission, message transmission and the like through the network 170.

The global network map database 230 includes a global information including at least one of service area information of a plurality of CDN providers contracted by a content provider, storage object information serviced by each CDN service provider, and IP address information of a client corresponding to each service area. It is a repository of network map information.

When the controller 220 receives an IP address of the content server 160 to transmit a page from the local name server 120 through the transceiver 210, the controller 220 transfers the IP address of the content server 160 to the local name server 120. send.

Subsequently, when the controller 220 receives an inquiry of the IP address of the server storing the object included in the page from the local name server 120 through the transceiver 210, the controller 220 determines the location of the client 110. The location of the client 110 is checked by checking the IP address of the client 110.

The controller 220 selects a specific CDN provider to transmit the corresponding object to the client 110 among the plurality of CDN providers by referring to the identified location of the client 110 and global network map information stored in the global network map database 230. do.

Thereafter, the controller 220 may include the domain name information of the selected CDN operator in the CNAME resource record and transmit the domain name information to the local name server 120 at the client 110 through the transceiver 210.

Information of the global network map included in the global network map database 230 will be described in more detail with reference to FIG. 3.

3 is an example of global network map 300 information stored in the global network map database shown in FIG. 2 of the present invention. The global network map 300 is map information referred to by the content provider name server 150 in the process of selecting a CDN service provider to respond to an object request of the client 110.

Referring to FIG. 3, the global network map 300 of the present embodiment includes continent information 310, country information 320, region information 330, CDN service provider information 340, storage object information 350, and IP address. It consists of a column of 360.

The continental information 310 item is a field containing information of each continent of the world.

The country information 320 item is a field containing country information included in each continent.

The area information 330 item is a field containing detailed area information included in each country.

The CDN provider information 340 item is a field containing CDN provider information including a replication server 130 that can provide CDN service to each region.

The storage object information 350 item is a field containing content information stored in a replication server of a CDN service provider providing a CDN service in each region.

The IP address 360 item is a field containing IP address information of a terminal and the like located in each region of the region information 330.

Referring to the global network map 300, the country information 320 corresponding to the North American continent in the continental information 310 item includes a country such as the United States, Canada, .... In addition, it can be seen that the New York, California, ... etc. belong to the regional information 330 corresponding to the item of the national information 320 of the United States. In addition, the provider of the CDN provider information 340 corresponding to the New York state of the area information 330 is 'XXX', which is a provider that provides services to the New York State among the providers of CDN services for the content provider's contents. Indicates that it is 'XXX'. And referring to the storage object information 350, it can be seen that the content stored in the replica server 130 of the 'XXX' operators that provide the CDN service to New York State is 'AAA', 'BBB'. In addition, referring to the IP address 360, the IP address of the terminal located in the New York State area is 'X.X.X'. In this case, 'X.X.X' represents one or more pieces of IP address information, and another IP address of the IP address 360 item also includes one or more pieces of IP address information.

If the client 110 located in New York State queries the IP address of the server that stores the specific object included in the page, the local name server 120 of the client 110 receiving the query may use the content provider name. The server 150 queries the server's IP address that stores the object.

The content provider name server 150 receiving the query determines the location of the client 110 using the IP address of the client 110, and the client 110 in the IP address 360 item of the global network map 300. Search for an IP address that matches the IP address.

The region corresponding to the corresponding IP address is searched by referring to the continental information 310, the country information 320, and the region information 330, and the CDN service provider 340 provides CDN service information that provides a service to the searched area. Search in the item.

Thereafter, the content held by the searched CDN service provider is searched in the storage object information 350 item, and if there is content that matches the object requested by the client 110, the domain name information of the searched CDN service provider is transmitted to the local name server 120. do. On the contrary, if there is no content that matches the object requested by the client 110, the CDN service provider selects the CDN service provider by searching whether the CDN service provider providing the service in another region stores the object and the domain name information of the CDN service provider. Will be transmitted to the local name server 120.

Since other information included in the global network map 300 also contains the above information, a detailed description thereof will be omitted.

A content distribution process through a plurality of CDN providers according to an embodiment of the present invention will be described in more detail with reference to FIG. 4.

4 is a flowchart illustrating a content distribution method through a plurality of CDN providers according to an embodiment of the present invention. Referring to FIG. 4, the replication server 130 receives and stores an object included in a web page of a content provider from the content server 160 (S400). Content transmission in step S400, for example, when there is a request from the replication server 130, may be set to be made every time, when an object in the content server 160 is updated (update), etc. have.

Thereafter, when the browser of the client 110 receives a URL for requesting content from the content server 160, the resolver of the client 110 queries the local name server 120 for the IP address of the content server 160. (S405).

The local name server 120 that receives the query for the IP address of the content server 160 in step S405 queries the content server name server 150 for the content server 160 IP address. (S410).

The content provider name server 150 receiving the query in step S410 transmits the IP address of the content server 160 to the local name server 120 (S415), and receives the IP address of the content server 160. The local name server 120 transmits the IP address of the content server 160 to the client 110 (S420).

In step S420, the client 110, which has received the IP address of the content server 160, requests the content from the content server 160 using the content server 160 (S425), and the content server 160 sends the page to the client 110. Transmit to (S430).

The client 110 receiving the page in step S430 parses the page (S435). If the client 110 finds the URL of the object included in the page while parsing the page in step S435, it queries the local name server 120 for the IP address of the server storing the object included in the page. (S440).

Upon receiving the IP address query in step S440, the local name server 120 queries the content provider name server 150 for the IP address of the server storing the object (S445).

Receiving the IP address query in step S445, the content provider name server 150 selects a CDN provider to transmit the corresponding object among the plurality of CDN providers by referring to the location of the client 110 (S450), and selects the selected CDN provider. The domain name information of the server is transferred to the local name server 120 (S455).

In step S450, for example, the location of the client 110 may be determined using the IP address information of the client 110. In operation S450, a CDN provider may be selected by referring to a global network map including at least one of service area information of a plurality of CDN providers and object information serviced by the plurality of CDN providers.

In operation S455, for example, the domain name information of the selected CDN provider may be included in the CNAME resource record and transmitted to the local name server 120.

The local name server 120 that has received the domain name information of the CDN provider in step S455 is a replica server for transmitting the object included in the page to the provider name server 140 which is the name server of the CDN provider corresponding to the corresponding domain name. The IP address is queried (S460).

The operator name server 140 receiving the query in step S460 selects a replication server 130 to transmit the corresponding object to the client 110 among one or more replication servers (S465). In step S465, for example, one or more pieces of data traffic information of one or more replication servers, local proximity information between one or more replication servers and the client 110, and object information stored by each of the one or more replication servers are considered. By selecting the optimal replication server 130.

The operator name server 140 transmits the IP address of the selected replication server 130 to the local name server 120 (S470), and the local name server 120 transmits the IP address of the received replication server 130. It transmits to the client 110 (S475).

The client 110 receiving the IP address in step S475 uses the same to request an object included in the page from the replication server 130 (S480), and the replication server 130 transmits the object to the client 110. It is transmitted to (S485).

According to the present invention, a content provider name server may select a particular provider from among a plurality of CDN providers to provide an object included in a page, and through this, a content provider may contract with a CDN provider who does not have a global network infrastructure. Even if it is concluded, it is possible to quickly respond to the content request of the client without a separate middle mile response delay.

1 is a block diagram of a content distribution system through a plurality of CDN operators according to an embodiment of the present invention.

FIG. 2 is a block diagram of a content provider name server shown in FIG. 1.

FIG. 3 is a configuration diagram of global network map information stored in the global network map database shown in FIG. 2.

4 is a flowchart illustrating a content distribution method according to an embodiment of the present invention.

Claims (17)

A storage step of receiving and storing an object included in a page from a content server by one or more replication servers of a plurality of content delivery network (CDN) providers; After the content provider name server that receives the IP (Internet Protocol) address query of the server storing the object from the local name server of the client that has received the page from the content server, confirms the location of the client, Based on a global network map including service area information of a CDN service provider, a CDN service provider including the location of the client as service area information is selected, and domain name information of the selected CDN service provider is transferred to the local name server. A delivery step of delivering; And The local name server obtains an IP address of a specific replication server to which the object is to be transmitted from the one or more replication servers in a provider name server corresponding to the domain name receiving the IP address query of the replication server storing the object from the local name server. A transmission step of transmitting to the client through; Content distribution method through a plurality of CDN providers comprising a. The method of claim 1, wherein the delivering step And the content provider name server refers to the location of the client using the IP address information of the client. delete The method of claim 1, wherein the delivering step The content provider name server includes the CDN provider domain name information in the CNAME (Canonical NAME) resource record and delivers to the local name server, Content distribution method through a plurality of CDN providers. The method of claim 4, wherein the transmitting step And the local name server queries the IP address of the replication server with reference to the CDN provider domain name information included in the CNAME resource record. The method of claim 1, wherein the transmitting step The specific replication server in consideration of at least one of data traffic information of the one or more replication servers, local proximity information between the one or more replication servers and clients, and object information stored by each of the one or more replication servers in the service provider name server. Transmitting the IP address to the local name server. A content server providing a page and an object included in the page; One or more replication servers of a plurality of CDN providers for receiving and storing the object from the content server; When receiving the IP address query of the server that stores the object from the local name server of the client that receives the page from the content server, after confirming the location of the client, including the service area information of the plurality of CDN operators A content provider name server configured to select a CDN provider including a location of the client as service area information based on a global network map, and to transfer domain name information of the selected CDN provider to the local name server; And Receiving an IP address query of a replica server storing the object from the local name server, transmitting the IP address of a specific replica server to which the object is to be transmitted from the one or more replica servers to the client via the local name server. A provider name server corresponding to the domain name; Content distribution system through a plurality of CDN operators comprising a. The method of claim 7, wherein the content provider name server And a location of the client by using the IP address information of the client. delete The method of claim 7, wherein the content provider name server And delivering the CDN service provider domain name information to the local name server by including the CNAME resource record in the CNAME resource record. 11. The method of claim 10, wherein the local name server And querying the IP address of the replication server with reference to the CDN provider domain name information included in the CNAME resource record. The method of claim 7, wherein the service provider name server The IP address of the specific replication server is determined in consideration of at least one of data traffic information of the one or more replication servers, local proximity information between the one or more replication servers and clients, and object information stored by each of the one or more replication servers. Content distribution system through a plurality of CDN providers, characterized in that the transmission to the name server. Transceiver for transmitting and receiving data; A global network map database storing service area information of a plurality of CDN operators; And When receiving the IP address query of the server storing the object included in the page from the local name server on the client side receiving the page from the content server, after confirming the location of the client, the global network map database A control unit configured to select a CDN service provider including the location of the client as service area information and to transmit domain name information of the selected CDN service provider to the local name server through the transceiver; Content provider name server comprising a. The method of claim 13, wherein the control unit And the location of the client is referred to using the IP address information of the client. 14. The system of claim 13, wherein the global network map database is The content provider name server, further comprising IP address information corresponding to the service area of the plurality of CDN providers. The method of claim 15, wherein the control unit And a CDN provider for transmitting the object by further referring to the IP address information. The method of claim 13, wherein the control unit And providing the CDN provider domain name information in the CNAME resource record to the local name server.

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