Managing content delivery network service providers

[0001] Generally described, computing devices and communication networks can be utilized to exchange information. In a common application, a computing device can request content from another computing device via the communication network. For example, a user at a personal computing device can utilize a software browser application to request a Web page from a server computing device via the Internet. In such embodiments, the user computing device can be referred to as a client computing device and the server computing device can be referred to as a content provider.

[0002] Content providers are generally motivated to provide requested content to client computing devices often with consideration of efficient transmission of the requested content to the client computing device and/or consideration of a cost associated with the transmission of the content. For larger scale implementations, a content provider may receive content requests from a high volume of client computing devices which can place a strain on the content provider's computing resources. Additionally, the content requested by the client computing devices may have a number of components, which can further place additional strain on the content provider's computing resources.

[0003] With reference to an illustrative example, a requested Web page, or original content, may be associated with a number of additional resources, such as images or videos, which are to be displayed with the Web page. In one specific embodiment, the additional resources of the Web page are identified by a number of embedded resource identifiers, such as uniform resource locators (“URLs”). In turn, software on the client computing devices typically processes embedded resource identifiers to generate requests for the content. Often, the resource identifiers associated with the embedded resources reference a computing device associated with the content provider such that the client computing device would transmit the request for the additional resources to the referenced content provider computing device. Accordingly, in order to satisfy a content request, the content provider(s) (or any service provider on behalf of the content provider(s)) would provide client computing devices data associated with the Web page and/or the data associated with the embedded resources.

[0004] Some content providers attempt to facilitate the delivery of requested content, such as Web pages and/or resources identified in Web pages, through the utilization of a network storage provider or a content delivery network (“CDN”) service provider. A network storage provider and a CDN server provider each typically maintain a number of computing devices in a communication network that can maintain content from various content providers. In turn, content providers can instruct, or otherwise suggest to, client computing devices to request some, or all, of the content provider's content from the network storage provider's or CDN service provider's computing devices.

[0005] As with content providers, network storage providers and CDN service providers are also generally motivated to provide requested content to client computing devices often with consideration of efficient transmission of the requested content to the client computing device and/or consideration of a cost associated with the transmission of the content. Accordingly, CDN service providers often consider factors such as latency of delivery of requested content in order to meet service level agreements or to generally improve the quality of delivery service.

[0013] Generally described, the present disclosure is directed to delivery of one or more resources associated with a content provider by selecting from available storage service providers and content delivery network (“CDN”) service providers. Specifically, aspects of the disclosure will be described with regard to the management of resource delivery by a network storage provider on behalf of a content provider as a function of request processing criteria. In one aspect, as a function of the request processing criteria, a network storage provider may identify a storage component associated with the network storage provider for processing a subsequent request by a client computing device. In another aspect, as a function of the request processing criteria, the network storage provider may select one or more CDN service providers for processing subsequent requests by a client computing device.

[0014] In an illustrative embodiment, the request processing criteria, or request processing information, can correspond to a financial cost attributed to the content provider for delivery of requested resources by the network storage provider or a CDN service provider. The request processing criteria can also correspond to quality of service characteristics associated with the delivery of requested resources by a network storage provider or CDN service provider including, but not limited to a volume of client computing device resource requests made to the network storage provider, available communication network bandwidth or communication network bandwidth utilization, measured or estimated latencies, error rates or counts, and the like. Still further, the request processing criteria can correspond to content provider or client computing device specified information, such as end user specified feedback. Although various aspects of the disclosure will be described with regard to illustrative examples and embodiments, one skilled in the art will appreciate that the disclosed embodiments and examples should not be construed as limiting.

[0015] FIG. 1 is a block diagram illustrative of content delivery environment 100 for the managing registration of content with a CDN service provider and subsequent processing of content requests. As illustrated in FIG. 1, the content delivery environment 100 includes a number of client computing devices 102 (generally referred to as clients) for requesting content from a content provider, a network storage provider 110, and/or a CDN service provider 106. In an illustrative embodiment, the client computing devices 102 can correspond to a wide variety of computing devices including personal computing devices, laptop computing devices, hand-held computing devices, terminal computing devices, mobile devices, wireless devices, various electronic devices and appliances and the like. In an illustrative embodiment, the client computing devices 102 include necessary hardware and software components for establishing communications over a communication network 108, such as a wide area network or local area network. For example, the client computing devices 102 may be equipped with networking equipment and browser software applications that facilitate communications via the Internet or an intranet.

[0016] Although not illustrated in FIG. 1, each client computing device 102 utilizes some type of local DNS resolver component, such as a DNS nameserver, that generates the DNS queries attributed to the client computing device. In one embodiment, the local DNS resolver component may be provide by an enterprise network to which the client computing device 102 belongs. In another embodiment, the local DNS resolver component may be provided by an Internet Service Provider (ISP) that provides the communication network connection to the client computing device 102.

[0017] The content delivery environment 100 can also include a content provider 104 in communication with the one or more client computing devices 102 via the communication network 108. The content provider 104 illustrated in FIG. 1 corresponds to a logical association of one or more computing devices associated with a content provider. Specifically, the content provider 104 can include a web server component 112 corresponding to one or more server computing devices for obtaining and processing requests for content (such as Web pages) from the client computing devices 102. The content provider 104 can further include an origin server component 114 and associated storage component 116 corresponding to one or more computing devices for obtaining and processing requests for network resources. One skilled in the relevant art will appreciate that the content provider 104 can be associated with various additional computing resources, such additional computing devices for administration of content and resources, DNS nameservers, and the like. For example, as further illustrated in FIG. 1, the content provider 104 can be associated with one or more DNS nameserver components 118 that would receive DNS queries associated with the domain of the content provider 104 and be authoritative to resolve client computing device DNS queries corresponding to a domain of the content provider 104 (e.g., return an IP address responsive to the DNS query). A DNS nameserver component is considered to be authoritative to a DNS query if the DNS nameserver can completely resolve the query by providing a responsive IP address. Additionally, the content provider 104 may include multiple components or eliminate some components altogether, such as origin server 114.

[0018] With continued reference to FIG. 1, the content delivery environment 100 can further include a CDN service provider 106 in communication with the one or more client computing devices 102, the content provider 104, and the network storage provider 110 via the communication network 108. The CDN service provider 106 illustrated in FIG. 1 corresponds to a logical association of one or more computing devices associated with a CDN service provider. Specifically, the CDN service provider 106 can include a number of Point of Presence (“POP”) locations 120, 126, 132 that correspond to nodes on the communication network 108. Each POP 120, 126, 132 includes a DNS component 122, 128, 134 made up of a number of DNS nameserver computing devices for resolving DNS queries from the client computers 102. Each POP 120, 126, 132 also includes a resource cache component 124, 130, 136 made up of a number of cache server computing devices for storing resources from content providers or network storage providers and transmitting various requested resources to various client computers. The DNS components 122, 128, 134 and the resource cache components 124, 130, 136 may further include additional software and/or hardware components that facilitate communications including, but not limited, load balancing or load sharing software/hardware components.

[0019] In an illustrative embodiment, the DNS component 122, 128, 134 and resource cache component 124, 130, 136 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, although the POPs 120, 126, 132 are illustrated in FIG. 1 as logically associated with the CDN service provider 106, the POPs will be geographically distributed throughout the communication network 108 in a manner to best serve various demographics of client computing devices 102. Additionally, one skilled in the relevant art will appreciate that the CDN service provider 106 can be associated with various additional computing resources, such additional computing devices for administration of content and resources, and the like.

[0020] With further continued reference to FIG. 1, the content delivery environment 100 can also include a network storage provider 110 in communication with the one or more client computing devices 102, the CDN service provider 106, and the content provider 104 via the communication network 108. The network storage provider 110 illustrated in FIG. 1 also corresponds to a logical association of one or more computing devices associated with a network storage provider. Specifically, the network storage provider 110 can include a number of network storage provider Point of Presence (“NSP POP”) locations 138, 144, 150 that correspond to nodes on the communication network 108. Each NSP POP 138, 144, 150 can include a storage management (“SM”) component 140, 146, 152 for obtaining requests for resources from the client computing devices 102 and determining whether the requested resource should be provided by a CDN service provider 106 or from a storage component associated with the network storage provider 110. In an illustrative embodiment, the storage management components 138, 144, 150 can be associated with one or more DNS nameserver components that are operative to receive DNS queries related to registered domain names associated with the network storage provider 110. The one or more DNS nameservers can be authoritative to resolve client computing device DNS queries corresponding to the registered domain names of the network storage provider 110. As similarly set forth above, a DNS nameserver component is considered to be authoritative to a DNS query if the DNS nameserver can resolve the query by providing a responsive IP address.

[0021] Each NSP POP 138, 144, 150 also includes a storage component 142, 148, 154 made up of a number of storage devices for storing resources from content providers which will be processed by the network storage provider 110 and transmitted to various client computers. The storage components 142, 148, 154 may further include additional software and/or hardware components that facilitate communications including, but not limited to, load balancing or load sharing software/hardware components. In an illustrative embodiment, the storage components 142, 148, 154 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, the network storage provider 110 may include a stand alone SM component 156 that provides CDN service provider recommendations to content providers 104, such as via a Web service.

[0022] Additionally, although the NSP POPs 138, 144, 150 are illustrated in FIG. 1 as logically associated with the network storage provider 110, the NSP POPs will be geographically distributed throughout the communication network 108 in a manner to best serve various demographics of client computing devices 102. Additionally, the network storage provider 110 can be associated with various additional computing resources, such additional computing devices for administration of content and resources, additional DNS nameservers, and the like. Even further, the components of the network storage provider 110 and components of the CDN service provider 106 can be managed by the same or different entities.

[0023] One skilled in the relevant art will appreciate that the components and configurations provided in FIG. 1 are illustrative in nature. Accordingly, additional or alternative components and/or configurations, especially regarding the additional components, systems and subsystems for facilitating communications may be utilized.

[0024] With reference now to FIGS. 2-6, the interaction between various components of the content delivery environment 100 of FIG. 1 will be illustrated. For purposes of the example, however, the illustration has been simplified such that many of the components utilized to facilitate communications are not shown. One skilled in the relevant art will appreciate that such components can be utilized and that additional interactions would accordingly occur without departing from the spirit and scope of the present disclosure.

[0025] With reference to FIG. 2, an illustrative interaction for registration of a content provider 104 with the network storage provider 110 will be described. As illustrated in FIG. 2, the storage provider content registration process begins with registration of the content provider 104 with the network storage provider 110. In an illustrative embodiment, the content provider 104 utilizes a registration application program interface (“API”) to register with the network storage provider 110 such that the network storage provider 110 can provide content on behalf of the content provider 104. The registration API includes the identification of the origin server 114 of the content provider 104 that will provide requested resources to the network storage provider 110. In addition or alternatively, the registration API includes the content to be stored by the network storage provider 110 on behalf of the content provider 104.

[0026] One skilled in the relevant art will appreciate that upon storage of the content by the network storage provider 110, the content provider 104 can begin to direct requests for content from client computing devices 102 to the network storage provider 110. Specifically, in accordance with DNS routing principles, a client computing device DNS request corresponding to a resource identifier would eventually be directed toward a storage component 140, 144, 148 of a NSP POP 138, 142, 146 associated with the network storage provider 110 (e.g., resolved to an IP address corresponding to a storage component).

[0027] In an illustrative embodiment, upon receiving the registration API, the network storage provider 110 obtains and processes the content provider registration information. In an illustrative embodiment, the network storage provider 110 can then generate additional information that will be used by the client computing devices 102 as part of the content requests. The additional information can include, without limitation, content provider identifiers, such as content provider identification codes, storage provider identifiers, such as storage provider identification codes, executable code for processing resource identifiers, such as script-based instructions, and the like. One skilled in the relevant art will appreciate that various types of additional information may be generated by the network storage provider 110 and that the additional information may be embodied in any one of a variety of formats.

[0028] The network storage provider 110 returns an identification of applicable domains for the network storage provider (unless it has been previously provided) and any additional information to the content provider 104. In turn, the content provider 104 can then process the stored content with content provider specific information. In one example, the content provider 104 translates resource identifiers originally directed toward a domain of the origin server 114 to a domain corresponding to the network storage provider 110. The modified URLs are embedded into requested content in a manner such that DNS queries for the modified URLs are received by a DNS nameserver corresponding to the network storage provider 110 and not a DNS nameserver corresponding to the content provider 104.

[0029] Generally, the identification of the resources originally directed to the content provider 104 will be in the form of a resource identifier that can be processed by the client computing device 102, such as through a browser software application. In an illustrative embodiment, the resource identifiers can be in the form of a uniform resource locator (“URL”). Because the resource identifiers are included in the requested content directed to the content provider, the resource identifiers can be referred to generally as the “content provider URL.” For purposes of an illustrative example, the content provider URL can identify a domain of the content provider 104 (e.g., contentprovider.com), a name of the resource to be requested (e.g., “resource.xxx”) and a path where the resource will be found (e.g., “path”). In this illustrative example, the content provider URL has the form of:

[0030] http://www.contentprovider.com/path/resource.xxx

[0031] During an illustrative translation process, the content provider URL is modified such that requests for the resources associated with the modified URLs resolve to a POP associated with the network storage provider 110. In one embodiment, the modified URL identifies the domain of the network storage provider 110 (e.g., “storageprovider.com”), the same name of the resource to be requested (e.g., “resource.xxx”) and the same path where the resource will be found (e.g., “path”). Additionally, the modified URL can include additional processing information (e.g., “additional information”). The modified URL would have the form of:

[0032] http://additional information.storageprovider.com/path/resource.xxx

[0033] In another embodiment, the information associated with the network storage provider 110 is included in the modified URL, such as through prepending or other techniques, such that the modified URL can maintain all of the information associated with the original URL. In this embodiment, the modified URL would have the form of:

[0034] http://additional information.storageprovider.com/www.contentprovider.com/path/resource.xxx

[0035] With reference now to FIG. 3, after completion of the registration and translation processes illustrated in FIG. 2, a first client computing device 102A subsequently generates a content request that is received and processed by the content provider 104, such as through the Web server 112. In accordance with an illustrative embodiment, the request for content can be in accordance with common network protocols, such as the hypertext transfer protocol (“HTTP”). Upon receipt of the content request, the content provider 104 identifies the appropriate responsive content. In an illustrative embodiment, the requested content can correspond to a Web page that is displayed on the client computing device 102A via the processing of information, such as hypertext markup language (“HTML”), extensible markup language (“XML”), and the like. The requested content can also include a number of embedded resource identifiers, described above, that corresponds to resource objects that should be obtained by the client computing device 102A as part of the processing of the requested content. The embedded resource identifiers will generally in the form of the modified URLs, described above.

[0036] Alternatively, the embedded resource identifiers can remain in the form of the content provider URLs that would be received and processed by a DNS nameserver associated with the content provider 104. In this alternative embodiment, the receiving DNS nameserver would use a canonical name record (“CNAME”) that would identify the network storage component 110. Upon receipt of the returned CNAME, the client computing device 102A subsequently transmits a DNS query corresponding to the received CNAME. The client computing device 102A can then process the received CNAME in a manner similar to the modified URLs, described below. For ease of illustration, however, the alternative embodiment will not be described in further detail and the additional processing steps will only be described with regard to the modified URL. One skilled in the relevant will appreciate that the below description may be applicable to CNAMEs as described in the alternative embodiment.

[0037] With reference now to FIG. 4A, upon receipt of the requested content, the client computing device 102A, such as through a browser software application, begins processing any of the markup code included in the content and attempts to acquire the resources identified by the embedded resource identifiers (e.g., the embedded, modified URLs). Accordingly, the first step in acquiring the content correspond to the issuance, by the client computing device 102 (through its local DNS resolver), a DNS query for the Original URL resource identifier that results in the identification of a DNS nameserver authoritative to the “.” and the “com” portions of the modified URL. After partially resolving the modified URL according to the “.” and “com” portions of the embedded URL, the client computing device 102A then issues another DNS query for the resource URL that results in “.storageprovider” portion of the embedded, modified URL. The issuance of DNS queries corresponding to the “.” and the “com” portions of a URL, such as the modified URL, are well known and have not been illustrated.

[0038] In an illustrative embodiment, the identification of the identification of a DNS nameserver authoritative to the “storageprovider” corresponds to an IP address of a DNS nameserver associated with the network storage provider 110. In one embodiment, the IP address is a specific network address unique to a DNS nameserver component of a POP. In another embodiment, the IP address can be shared by one or more POPs. In this embodiment, a further DNS query to the shared IP address utilizes a one-to-many network routing schema, such as anycast, such a specific POP will receive the request as a function of network topology. For example, in an anycast implementation, a DNS query issued by a client computing device 102A to a shared IP address will arrive at a DNS nameserver component of the network storage provider 110 logically having the shortest network topology distance, often referred to as network hops, from the client computing device. The network topology distance does not necessarily correspond to geographic distance. However, in some embodiments, the network topology distance can be inferred to be the shortest network distance between a client computing device 102A and a network storage provider POP. With continued reference to FIG. 4A, once one of the DNS nameservers in the network storage provider 110 receives the request, the specific DNS nameserver attempts to resolve the request.

[0039] As will be explained in detail below, to resolve the DNS query, the SM components 140, 146, 152, 156 (such as via the DNS nameserver component associated with the SM components) of the network storage provider 110 can maintain request processing criteria regarding the processing of requests for each resource, or a subset of resources, provided by the content provider 104. In an illustrative embodiment, the SM components 140, 146, 152, 156 utilizes the request processing criteria to determine whether a subsequent request for the resource should be processed by a storage component of the network storage provider 110 or whether the subsequent request for the resource should be processed by a CDN service provider 106. The request processing criteria can include the total number of requests obtained by the network storage provider 110 for a resource over a defined period of time, trends regarding an increase/decrease in requests for the resource, a current financial cost associated with the delivery of the resource by the network storage provider, quality of service metrics measured by the network storage provider 110 or CDN service provider 106, additional criteria provided by the content provider 104, and various combinations or alternatives thereof. An alternative in which the SM components 140, 146, 152, 156 select a CDN service provider 106 will be described with regard to FIGS. 5A-5C.

[0040] With continued reference to FIG. 4A, based on the request processing criteria maintained by the SM components 140, 146, 152, 156 (either individually maintained or shared), in some embodiments, the network storage provider 110 can utilize processing criteria to select that a storage component associated with the network storage provider 110 should process the subsequent request for the resource by the client computing devices 102A. In an illustrative embodiment, the receiving DNS nameserver can resolve the DNS query by identifying an IP address of a network storage provider storage component 142, 148, 154 (FIG. 1) that will process the request for the requested resource. The DNS nameserver of the SM components 140, 146, 152, 156 can utilize at least a portion of request processing criteria to the specific IP address of a network storage provider storage component 142, 148, 154 (FIG. 1). Additionally, the SM components 140, 146, 152, 156 can further utilize additional request processing criteria associated only with the selection of the network storage provider storage component 142, 148, 154 and not utilized to select between the network storage provider 110 or the CDN service provider 106. Still further, the SM components 140, 146, 152, 156 can utilize additional request routing methodologies such as current communication network conditions, often referred to as “Internet weather,” or other selection methodologies, such as round-robin selection or prioritized lists.

[0041] With reference now to FIG. 4B, upon receipt of the successful resolution of the DNS query to the storage provider component (e.g., a DNS query corresponding to the modified URL http://additional information.storageprovider.com/path/resource.xxx), the client computing device 102A transmits embedded resource requests to the network storage provider storage component 142, 148, 154 (FIG. 1) corresponding to the previously provided IP address. In turn, the receiving network storage provider storage component can process the request by providing the requested content obtained from the origin server 114 of the content provider 104. The requested content can be transmitted to the requesting client computing device 102A via the communication network 108.

[0042] With reference now to FIGS. 5A-5C, assume that the content provider has authorized (directly or indirectly) the utilization of a CDN service provider 106. In one embodiment, the content provider 104 can authorize the implementation of a CDN server provider 106 in accordance with APIs or graphical user interfaces that facilitate the authorization and initialization of one or more CDN service providers 106. Additionally, the content provider 104 can implement logic, or programmatic instructions, that facilitate the authorization and initialization of one or more CDN service providers 106 without requiring human interaction. Subsequent to the authorization of the utilization of the CDN service provider 106, a client computing device, illustratively client computing device 102B, repeats the request for a resource and is returned the requested resource with a number of embedded resource (similar to the interaction illustrated in FIG. 3).

[0043] With reference to FIG. 5A, to obtain the requested resources, the client computing device 102B transmits a DNS query for an embedded resource (e.g., (e.g., http://additional information.storageprovider.com/path/resource.xxx), which is received by a DNS nameserver at the network storage provider 110, such as the DNS nameserver component associated with one of the SM components 140, 144, 150, 156. As described above with regard to FIG. 4A, the receiving DNS nameserver attempts to resolve the client computing device DNS query. As also described above, to resolve the DNS query, the SM components 140, 146, 152, 156 (such as via the DNS nameserver component associated with the SM components) of the network storage provider 110 can maintain request processing criteria regarding the processing of requests for each resource, or a subset of resources, provided by the content provider 104. In an illustrative embodiment, the SM components 140, 146, 152, 156 utilizes the request processing criteria to determine whether a subsequent request for the resource should be processed by a storage component of the network storage provider 110 or whether the subsequent request for the resource should be processed by a CDN service provider 106.

[0044] With continued reference to FIG. 5A, based on the request processing criteria maintained by the SM components 140, 146, 152, 156 (either individually maintained or shared), in some embodiments, the network storage provider 110 can utilize processing criteria to select that a resource cache component associated with the CDN service provider 106 should process the subsequent request for the resource by the client computing devices 102B (as opposed to a network storage component of the network storage provider 110). Accordingly, instead of resolving the DNS query by providing an IP address associated with a storage provider storage component 142, 148, 154, the network storage provider 110 can maintain sets of various alternative resource identifiers corresponding to one or more CDN service providers 106. The alternative resource identifiers can be provided by the network storage provider 110 to the client computing device 102B such that a subsequent DNS query on the alternative resource identifier will partially resolve to a DNS nameserver component within the CDN service provider's network. The network storage provider 110 may select (or otherwise obtain) an alternative resource identifier that is intended to resolve to an appropriate DNS nameserver of the CDN service provider 106 based on a variety of criteria. For example, the network storage provider may select an alternative resource identifier based on a regional service plan or service level information obtained from the content provider. As will be described further below, this additional information may also be used for further request routing.

[0045] In an illustrative embodiment, the alternative resource identifiers are in the form of one or more CNAME records. In one embodiment, each CNAME record identifies a domain of the CDN service provider 106 (e.g., “cdnprovider.com” or “cdnprovider-1.com”). As will be explained in greater detail below, the domain in the CNAME does not need to be the same domain found in original URL. Additionally, each CNAME record includes additional information, such as request routing information, (e.g., “request routing information”). An illustrative CNAME record can have the form of:

• • [0046] http://additional information.storageprovider.com/path/resource.xxx CNAME request_routing_information.cdnprovider.com

[0047] In accordance with this illustrative embodiment, the network storage provider 110 maintains a data store that defines CNAME records for various URLs corresponding to embedded resources stored by the network storage provider 110. If a DNS query corresponding to a particular URL matches an entry in the data store, the network storage provider 110 returns a CNAME record to the client computing device 102B that will direct the client computing device to a CDN service provider 106.

[0048] The returned CNAME can also include request routing information that is different from or in addition to the information provided in URL of the current DNS query. For example, if the CNAME selection is based on a regional service plan or a service level plan selected by the content provider 104, a specific identifier can be included in the “request_routing_information” portion of the specific CNAME record. In another embodiment, request routing information can be found in the identification of a CDN service provider 106 domain different from the domain found in the original URL. For example, if the CNAME is based on a regional plan, a specific regional plan domain (e.g., “cdnprovder-region1.com”) could be used in the domain name portion of the specific CNAME record. Any additional request routing information can be prepended to the existing request routing information in the original URL such that the previous request routing information would not be lost (e.g., http://serviceplan.regionalplan.cdnprovider.com). One skilled in the relevant art will appreciate that additional or alternative techniques and/or combination of techniques may be used to include the additional request routing information in the CNAME record that is identified by the network storage provider 110.

[0049] With reference now to FIG. 5B, once the client computing device 102B obtains the returned CNAME, the client computing device generates a subsequent DNS query corresponding to the CNAME. As previously discussed with regard to FIG. 4A, the DNS query process could first start with DNS queries for the “.” and “com” portions, followed by a query for the “cdnprovider” portion of the CNAME. To the extent, however, that the results of a previous DNS queries can be cached (and remain valid), the client computing device 102B can utilize the cached information and does not need to repeat the entire process. Similar to the process described with regard to FIGS. 4A and 5A, the client computing device 102B issues a DNS query for the resource URL that results in “.cdnprovider” portion of the CNAME.

[0050] In an illustrative embodiment, the identification of the identification of a DNS nameserver authoritative to the “cdnprovider” corresponds to an IP address of a DNS nameserver associated with the CDN server provider, such as DNS nameserver components 122, 128, 134 (FIG. 1). In one embodiment, the IP address is a specific network address unique to a DNS nameserver component of a POP. In another embodiment, the IP address can be shared by one or more POPs. In this embodiment, a further DNS query to the shared IP address utilizes a one-to-many network routing schema, such as anycast, such a specific POP will receive the request as a function of network topology. For example, in an anycast implementation, a DNS query issued by a client computing device 102B to a shared IP address will arrive at a DNS nameserver component 122, 128, 134 (FIG. 1) of the CDN service provider 106 logically having the shortest network topology distance, often referred to as network hops, from the client computing device. As previously discussed, the network topology distance does not necessarily correspond to geographic distance. However, in some embodiments, the network topology distance can be inferred to be the shortest network distance between a client computing device 102B and a network storage provider POP 120, 126, 132 (FIG. 1).

[0051] In an illustrative embodiment, the DNS nameserver components, illustratively DNS nameserver component 128, can utilize a variety of information in selecting a resource cache component. In one example, the DNS nameserver component 128 can default to a selection of a resource cache component of the same POP. In another example, the DNS nameserver components can select a resource cache component based on various load balancing or load sharing algorithms. Still further, the DNS nameserver components can utilize network performance metrics or measurements to assign specific resource cache components. The IP address selected by a DNS nameserver component may correspond to a specific caching server in the resource cache. Alternatively, the IP address can correspond to a hardware/software selection component (such as a load balancer).

[0052] With reference now to FIG. 5C, in an illustrative example, assume that the CDN service provider 106 has selected the resource cache component 130 of POP 126 (FIG. 1). Upon receipt of the IP address for the resource cache component 130, the client computing device 102B transmits requests for the requested content to the resource cache component 130. The resource cache component 130 processes the request in a manner described above and the requested content is transmitted to the client computing device 102B.

[0053] As previously described, the network storage provider 110 maintains the table of alternative resource identifiers (e.g. CNAMES) that are used to direct a client computing device 102 to a CDN service provider 106. In an illustrative embodiment, the network storage provider 110 can manage the list of alternative resource identifiers such that the content provider 104 can utilize a different CDN service provider 106. For example, the network storage provider 110 can continuously calculate a cost associated with processing requests for specific resources and make updated recommendations regarding the utilization of a CDN service provider 106 or the utilization of a different CDN service provider.

[0054] With reference now to FIG. 6, a flow diagram illustrative of a resource DNS query processing routine 600 implemented by a network storage provider 110 will be described. One skilled in the relevant art will appreciate that actions/steps outlined for routine 600 may be implemented by one or many computing devices/components that are associated with the network storage provider 110. Accordingly, routine 600 has been logically associated as being performed by the network storage provider 110.

[0055] At block 602, one of the DNS nameservers at one of the SM components 140, 146, 152, 156 (or corresponding to the network storage provider 110) receives a DNS query corresponding to resource identifier. As previously discussed, the resource identifier can be a URL that has been embedded in content requested by the client computing device 102 and previously provided by the content provider 104. At decision block 604, a test is conducted to determine whether the receiving DNS nameserver is authoritative to resolve the DNS query. In an illustrative embodiment, the receiving DNS nameserver can determine whether it is authoritative to resolve the DNS query if there are no CNAME records corresponding to the received resource identifier. As previously discussed, for purposes of the routine 600, a DNS nameserver component is considered to be authoritative to a DNS query if the DNS nameserver can resolve the query by providing a responsive IP address associated with network storage provider storage component 142, 148, 154 (FIG. 1). In this context, the DNS nameserver may be operative to receive DNS queries on behalf network storage provider 110, but not authoritative if the DNS query cannot be completely resolved by providing a responsive IP address.

[0056] As previously described, to determine whether the DNS query can be resolved to an IP address of the network storage provider storage component 142, 148, 154 (FIG. 1) or whether an alternate resource identifier should be provided, the receiving DNS nameserver utilizes request processing criteria to make such a determination. In an illustrative embodiment, the receiving DNS nameserver will utilize the cost information, at least in part, to make such a determination. The cost information corresponds to a financial cost attributable to the content provider 104 for the delivery of resources by the network storage provider 110 and the CDN service provider 106. The financial cost may be defined in a variety of ways and can be obtained by the SM components 140, 146, 152, 156 in a variety of ways.

[0057] In one example, the cost information may designate that the content provider 104 has requested that the SM components 140, 146, 152, 156 select the service provider (generally referred to as either the network storage provider 110 or a CDN service provider 106) associated with the lowest current financial cost to provide the requested resource. Accordingly, the SM components 140, 146, 152, 156 could obtain cost information for at least a portion of the POPs and select the server provider (e.g., the network storage provider 110 or the CDN service provider 106) associated with the lowest financial cost. The financial cost information utilized to select the lowest financial costs may be based on a current financial costs or projected financial costs. The projected financial costs can be based on criteria, such as time of day, characteristics of the resource (e.g., size of the data, type of data, etc.), anticipated data throughput volumes, current loads experienced by each service provider, and the like. For example, if a service provider's POP resources are at an optimal capacity, the service provider may project financial cost at a premium cost level (e.g., a highest cost level) because any additional data traffic would cause the resources to operate above optimal rates. Conversely, the service provider may project lower financial costs for specific POPs according to historically known low volume times (e.g., time of day, days of the month, time of the year, special days/holidays, etc.). The financial cost information may be a single cost projected for each identifiable service provider. Alternatively, the financial cost information may be a set of costs associated with one or more identifiable components of each service provider (e.g., financial information for one or more POPs associated with a service provider).

[0058] In another example, the cost information may designate the content provider 104 has requested that the cost associated with the providing the requested resource be maintained below one or more cost thresholds or cost tiers. Accordingly, the SM components 140, 146, 152, 156 could obtain financial cost information for the available service providers and select only those service providers with a financial cost at or below the cost thresholds. The SM components 140, 146, 152, 156 could then utilize other request processing criteria to select from the selected DNS nameserver (if more than one DNS nameserver is identified) or selected in accordance with other selections methodologies (e.g., random, round robin, etc.).

[0059] In another embodiment, the SM components 140, 146, 152, 156 can a determined/projected volume of request information for selecting a service provider. The determined/projected volume of request information can include the total number of requests obtained by the network storage provider 110 for a resource over a defined period of time, trends regarding an increase/decrease in requests for the resource, and various combinations or alternatives thereof.

[0060] In a further embodiment, the SM components 140, 146, 152, 156 can utilize geographic criteria for selecting a service provider. The geographic criteria can correspond to geographic-based regional service plans available between the service providers and the content provider 104. Accordingly, a client computing device 102 DNS query received in a region not corresponding to the content provider's regional plan may be better processed by a DNS nameserver in region corresponding to the content provider's regional plan. In this example, the SM components 140, 146, 152, 156 also obtain geographic information from the client directly (such as information provided by the client computing device or ISP) or indirectly (such as inferred through a client computing device's IP address).

[0061] In yet another embodiment, the SM components 140, 146, 152, 156 can utilize service level criteria for selecting a service provider. The service level criteria can correspond to service or performance metrics contracted between the available service providers and the content provider 104. Examples of performance metrics can include latencies of data transmission between the service provider POPs and the client computing devices 102, total data provided on behalf of the content provider 104 by the service provider POPs, error rates for data transmissions, and the like.

[0062] In still a further embodiment, the SM components 140, 146, 152, 156 can utilize network performance criteria for selecting a service provider. The network performance criteria can correspond to measurements of network performance for transmitting data from the service provider POPs to the client computing device 102. Examples of network performance metrics can include network data transfer latencies (measured by the client computing device or the service providers, network data error rates, and the like.

[0063] In another embodiment, the SM components 140, 146, 152, 156 can utilize content provider specified criteria for selecting a service provider. The content provider specified criteria can correspond to a variety of measurements or metrics specified by the content provider 104 and related to the delivery of resources on behalf of the content provider. The measurements or metrics can include content provider specified quality metrics (e.g., error rates), user complaints or error reports, and the like.

[0064] In accordance with an illustrative embodiment, the DNS nameserver maintains a data store that defines CNAME records for various URLs. If a DNS query corresponding to a particular URL matches an entry in the data store, the SM components 140, 146, 152, 156 returns a CNAME record as defined in the data store. In an illustrative embodiment, the data store can include multiple CNAME records corresponding to a particular original URL. The multiple CNAME records would define a set of potential candidates that can be returned to the client computing device. In an illustrative embodiment, each the SM component 140, 146, 152, 156 maintains the same data stores that define CNAME records, which can be managed centrally by the network storage provider 110. Alternatively, each SM component 140, 146, 152, 156 can maintain specific data stores that define CNAME records, which can be managed centrally by the network storage provider 110 or locally at the SM component 140, 146, 152, 156.

[0065] The returned CNAME can also include request routing information that is different from or in addition to the information provided in URL/CNAME of the current DNS query. For example, if the CNAME selection is based on regional plan, a specific regional plan can be identified in the “request_routing_information” portion of the specific CNAME record. A similar approach could be taken to identify service level plans and file management by including a specific identifier in the “request_routing_information” portion of the CNAME record. In another embodiment, request routing information can be found in the identification of a CDN service provider 106 domain different from the domain found in the current URL/CNAME. For example, if the CNAME is based on regional plan, a specific regional plan domain (e.g., “cdnprovder-region1.com”) could be used in the domain name portion of the specific CNAME record. Any additional request routing information can be prepended to the existing request routing information in the current URL/CNAME such that the previous request routing information would not be lost (e.g., serviceplan.regionalplan.cdnprovider.com). One skilled in the relevant art will appreciate that additional or alternative techniques and/or combination of techniques may be used to include the additional request routing information in the CNAME record that is selected by the SM components 140, 146, 152, 156.

[0066] Alternative or additional methodologies may also be practiced to determine whether the DNS nameserver is authoritative.

[0067] If at decision block 604 the receiving DNS nameserver is not authoritative, at block 606, the DNS nameserver selects and transmits an alternative resource identifier. As described above, the DNS nameserver can utilize a data store to identify an appropriate CNAME as a function of the current DNS query. Additionally, the DNS nameserver component can also implement additional logical processing to select from a set of potential CNAMES. The routine 600 proceeds to block 610.

[0068] Alternatively, if the receiving DNS nameserver is authoritative (including a determination that the same DNS nameserver will be authoritative for subsequent DNS queries), the receiving DNS nameserver resolves the DNS query by identifying the IP address of network storage provider storage component 142, 148, 154 (FIG. 1) at block 608. In a non-limiting manner, a number of methodologies for selecting an appropriate network storage provider storage component 142, 148, 154 have been previously discussed and may be utilized by the network storage provider 110.

[0069] At block 610, the receiving DNS nameserver returns the DNS query result to the requesting client computing device 102. As previously described, the DNS query result can include an identification of an IP address of a network storage provider storage component 142, 148, 154 if the network storage component 110 is going to process the subsequent resource request or a CNAME if a CDN service provider 106 will process the subsequent resource request. At block 612, the routine 600 terminates.

[0070] While illustrative embodiments have been disclosed and discussed, one skilled in the relevant art will appreciate that additional or alternative embodiments may be implemented within the spirit and scope of the present disclosure. Additionally, although many embodiments have been indicated as illustrative, one skilled in the relevant art will appreciate that the illustrative embodiments do not need to be combined or implemented together. As such, some illustrative embodiments do not need to be utilized or implemented in accordance with the scope of variations to the present disclosure.

[0071] Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements or steps. Thus, such conditional language is not generally intended to imply that features, elements or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements or steps are included or are to be performed in any particular embodiment. Moreover, unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey utilization of the conjunction “or” in enumerating a list of elements does not limit the selection of only a single element and can include the combination of two or more elements.

[0072] Any process descriptions, elements, or blocks in the flow diagrams described herein and/or depicted in the attached figures should be understood as potentially representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps in the process. Alternate implementations are included within the scope of the embodiments described herein in which elements or functions may be deleted, executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those skilled in the art. It will further be appreciated that the data and/or components described above may be stored on a computer-readable medium and loaded into memory of the computing device using a drive mechanism associated with a computer-readable medium storing the computer executable components, such as a CD-ROM, DVD-ROM, or network interface. Further, the component and/or data can be included in a single device or distributed in any manner. Accordingly, general purpose computing devices may be configured to implement the processes, algorithms and methodology of the present disclosure with the processing and/or execution of the various data and/or components described above. Alternatively, some or all of the methods described herein may alternatively be embodied in specialized computer hardware. In addition, the components referred to herein may be implemented in hardware, software, firmware or a combination thereof.

[0073] It should be emphasized that many variations and modifications may be made to the above-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.