# Patent

## Title
DNS query processing using resource identifiers specifying an application broker

## Abstract

A system, method and computer-readable medium for request routing based on application information associated with the requested resource are provided. A DNS nameserver at an application broker obtains a DNS query corresponding to a resource requested from a client computing device and associated with a first resource identifier. The first resource identifier includes application information associated with the requested resource. Based on the application information parsed from the first resource identifier, the DNS nameserver at the application broker selects either a second resource identifier which resolves to a domain of a network computing provider or an IP address associated with a network computing component for processing the requested resource. The DNS nameserver then transmits either the second resource identifier or IP address to the client computing device.

## Background
BACKGROUND
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.
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.
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, that 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 as well as the data associated with the embedded resources.
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 service provider each typically maintains 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. Upon receipt of resource requests from such client computing devices, a CDN service provider also typically delivers the requested resource in accordance with terms (such as via a service plan) specified between a corresponding content provider and the CDN service provider.
With reference to previous illustrative example, the content provider can leverage a network storage provider or CDN service provider with the modification or substitution of resource identifiers associated with the embedded resources. Specifically, the resource identifiers can reference a computing device associated with the network storage provider or CDN service provider such that the client computing device would transmit the request for the additional resources to the referenced network storage provider or CDN service provider computing device. Typically, the content provider facilitates the utilization of a network storage provider or CDN provider by including network storage provider or CDN-provider specific resource identifiers in requested content (e.g., Web pages).
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, such 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.



BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a block diagram illustrative of content delivery environment including a number of client computing devices, content provider, a content delivery network service provider, a network storage provider, and a network computing provider;
FIG. 2 is a block diagram of the content delivery environment of FIG. 1 illustrating the registration of a content provider with an application broker;
FIG. 3A is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of a content request from a client computing device to a content provider;
FIG. 3B is a block diagram of the content delivery environment of FIG. 1 illustrating one embodiment of the generation and processing of a DNS query corresponding to an embedded resource from a client computing device to an application broker;
FIG. 4 is a block diagram of the content delivery environment of FIG. 1 illustrating the generation and processing of an embedded resource request from a client computing device to a network computing provider; and
FIG. 5 is a flow diagram illustrative of a request routing routine implemented by an application broker for selecting a network computing component for processing a resource request.



DETAILED DESCRIPTION
Generally described, the present disclosure is directed to routing of a DNS query from a client computing device to a network computing component via an application broker for processing requested content associated with the DNS query. Specifically, aspects of the disclosure will be described with regard to the routing of a client computing device DNS query as a function of application information associated with resources requested by the client computing device. In certain embodiments, application information may be exclusively included within the resource identifiers utilized in the DNS queries received by the application broker from the client computing device. In other embodiments, the DNS queries may include information that permits the application broker to retrieve application information (or additional application information) associated with the requested resources. In any case, upon determining the application information for the requested resources, the application broker may select network computing components on the basis of this application information to process resource requests from client computing devices. Alternatively, the application broker may select an alternative resource identifier based on the application information. 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.
FIG. 1 is a block diagram illustrative of content delivery environment 100 for the management and 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 104, an application broker 111, one or more network storage providers 110, one or more network computing providers, and/or one or more CDN service providers 106. In an illustrative embodiment, the client computing devices 102 can corresponds 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.
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 102. 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.
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. The content provider 104 can still further include an application server computing device 118, such as a data streaming server for processing streaming content requests.
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, although not illustrated in FIG. 1, the content provider 104 can be associated with one or more DNS nameserver components that would be authoritative to resolve client computing device DNS queries corresponding to a domain of the content provider. 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 omit some of the components illustrated in FIG. 1, such as the origin server 114.
With continued reference to FIG. 1, the content delivery environment 100 can further include one or more CDN service providers 106 in communication with the one or more client computing devices 102, the content provider 104, the application broker 111, the one or more network storage providers 110, and/or the one or more network computing providers 107 via the communication network 108. Each 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 that correspond to nodes on the communication network 108. Each CDN POP 120 includes a DNS component 122 made up of a number of DNS server computing devices for resolving DNS queries from the client computers 102. Each CDN POP 120 also includes a resource cache component 124 made up of a number of cache server computing devices for storing resources from content providers and transmitting various requested resources to various client computers. The DNS component 122 and the resource cache component 124 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 DNS component 122 and resource cache component 124 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, although the CDN POPs 120 are illustrated in FIG. 1 as logically associated with the CDN provider 106, the CDN 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.
With further continued reference to FIG. 1, the content delivery environment 100 can also include one or more network computing providers 107 in communication with the one or more client computing devices 102, the CDN service provider 106, the network storage providers 110, the application broker 111 and/or the content provider 104 via the communication network 108. Each network computing provider 107 illustrated in FIG. 1 also corresponds to a logical association of one or more computing devices associated with a network computing provider. Specifically, the network computing provider 107 can include a number of Point of Presence (“POP”) locations 134, 142, 148 that correspond to nodes on the communication network 108. Each POP 134, 142, 148 includes a network computing component (NCC) 136, 144, 150 for hosting applications, such as data streaming applications, via a number of instances of a virtual machine, generally referred to as an instance of a NCC. One skilled in the relevant art will appreciate that NCC 136, 144, 150 would include physical computing device resources and software to provide the multiple instances of a virtual machine or to dynamically cause the creation of instances of a virtual machine. Such creation can be based on a specific request, such as from a client computing device, or the NCC can initiate dynamic creation of an instance of a virtual machine on its own. Each NCC POP 134, 142, 148 can also include a storage component made up of a number of storage devices for storing resources from content providers which will be processed by an instance of a NCC 136, 144, 150 and transmitted to various client computers. The NCCs 136, 144, 150 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 for selecting instances of a virtual machine supporting a requested application and/or providing information to a DNS nameserver to facilitate request routing. Accordingly, reference herein to selection of a NCC (e.g., an IP address associated with a NCC) can include selection of a specific instance of a NCC or selection of load balancing or load sharing component of a NCC which can in turn subsequently select a specific instance of the NCC.
In an illustrative embodiment, NCCs 136, 144, 150 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, although the NCC POPs 134, 142, 148 are illustrated in FIG. 1 as logically associated with the network computing provider 107, the NCC 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 network computing provider 107 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, the network computing provider 107 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 computing provider 107. 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 computing provider 107. 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.
With further continued reference to FIG. 1, the content delivery environment 100 can also include one or more network storage providers 110 in communication with the one or more client computing devices 102, the one or more CDN service providers 106, the application broker 111, the one or more network computing providers 107, and/or the content provider 104 via the communication network 108. Each 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, 142, 146 that correspond to nodes on the communication network 108. Each NSP POP 138, 142, 146 includes a storage component 140, 144, 148 made up of a number of storage devices for storing resources from content providers or content brokers which will be processed by the network storage provider 110 and transmitted to various client computers. The storage components 140, 144, 148 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 140, 144, 148 are considered to be logically grouped, regardless of whether the components, or portions of the components, are physically separate. Additionally, although the NSP POPs 138, 142, 146 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, one skilled in the relevant art will appreciate that the network storage provider 110 can be associated with various additional computing resources, such as additional computing devices for administration of content and resources, DNS nameservers, and the like. For example, the network storage provider 110 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. Again, 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.
With further continued reference to FIG. 1, the content delivery environment 100 can also include an application broker 111 in communication with the one or more client computing devices 102, the one or more CDN service providers 106, the one or more network storage providers 110, the one or more network computing providers 107, and/or the content provider 104 via the communication network 108. The application broker 111 illustrated in FIG. 1 also corresponds to a logical association of one or more computing devices associated with an application broker. Specifically, the application broker 111 can include an application management (“AM”) component 152 for monitoring requests for resources requiring use of an application to provide the resource to the requesting computing device. Additionally, the AM component 152 can be utilized in the process of either selecting a NCC for hosting the application and thereby providing the requested resource or selecting an alternative resource identifier of a domain that may be authoritative to resolve the request.
One skilled in the relevant art will appreciate that the application broker 111 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 application broker 111 can be associated with one or more DNS nameserver components 150 that are operative to receive DNS queries related to registered domain names associated with the application broker 111. As will be further described below, the one or more DNS nameserver components 150 can be authoritative to resolve client computing device DNS queries corresponding to the registered domain names of the application broker 111. Yet again, 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.
Even further, one skilled in the relevant art will appreciate that the components of the network storage provider 110, the network computing provider 107, the CDN service provider 106, and the application broker 111 can be managed by the same or different entities. One skilled in the relevant art will also 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.
With reference now to FIGS. 2-4, 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.
With reference to FIG. 2, an illustrative interaction for registration of a content provider 104 with the application broker 111 will be described. As illustrated in FIG. 2, the application broker registration process begins with registration of the content provider 104 with the application broker 111. In an illustrative embodiment, the content provider 104 utilizes a registration application program interface (“API”) to register with the application broker 111 such that the application broker 111 can facilitate use of one or more NCCs of one or more network computing providers 107 to provide content utilizing an application on behalf of the content provider 104. The registration API can include the identification of the origin server 114 of the content provider 104 that will provide requested resources to a selected NCC of a network computing provider. In another embodiment, the content provider 104 and/or the application broker 111 may facilitate using a network storage provider 110 as an origin server for the content provider 104. Additionally, the registration API can further facilitate the specification of service levels, financial cost criteria, or other content provider specified criteria that can be utilized by the application broker 111 in request routing processing.
One skilled in the relevant art will appreciate that upon registration of content with the application broker 111, the content provider 104 can begin to direct requests for content from client computing devices 102 to the application broker 111. Specifically, in accordance with DNS routing principles, and as will be described in further detail below, a client computing device request corresponding to a resource identifier would eventually be directed toward a NCC 136, 144, 150 associated with a network computing provider 107.
With continued reference to FIG. 2, upon receiving the registration API, the application broker 111 obtains and processes the content provider registration information. In an illustrative embodiment, the application broker 111 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, client identifiers, such as client identification codes, content provider identifiers, such as content provider identification codes, executable code for processing resource identifiers, such as script-based instructions, the like. In another embodiment, the additional information can include file type identifiers and/or application identifiers which can include file type information, as well as information pertaining to a type of application for processing the requested content or a specific instance of an application desired for processing the requested content. Application identifiers may also include or be associated with other additional information or requirements for selecting an instance of an application for processing the requested content, such as quality of service criteria which can include information as to compression rates, processing power, processing speed, and/or bandwidth of the NCC, and the like. One skilled in the relevant art will appreciate that various types of additional information may be generated by the application broker 111 and that the additional information may be embodied in any one of a variety of formats.
In one embodiment, the application broker 111 returns an identification of applicable domains for the application broker (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 the application broker specified information. In one example, as illustrated in FIG. 2, the content provider 104 modifies resource identifiers originally directed toward a domain of the origin server 114 to a domain corresponding to the application broker 111. The modified URLs are embedded into requested content in a manner such that DNS queries for the modified URLs will resolve to a DNS server corresponding to the application broker 111 and not a DNS server corresponding to the content provider 104. Although the modification process is illustrated in FIG. 2, in some embodiments, the modification process may be omitted in a manner described in greater detail below.
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:

    
    
        http://www.contentprovider.com/path/resource.xxx
    
    


During an illustrative modification process, the content provider URL is modified such that requests for the resources associated with the modified URLs resolve to the application broker 111. In one embodiment, the modified URL identifies the domain of the application broker 111 (e.g., “applicationbroker.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 various additional pieces of information utilized by the application broker 111 during the request routing process. Specifically, in an illustrative embodiment, the modified URL can include an application identifier and/or data otherwise corresponding to application information or criteria utilized by the application broker 111 during the request routing process (hereinafter collectively referred to as “application information”). Accordingly, as similarly described above, the application information can include, but is not limited to, client identifiers, content provider identifiers, file type identifiers, application identifiers, and the like. In one example, the application information can correspond to a file type identifier that can thereafter be used by the application broker 111, such as via a lookup, to determine information regarding an application for use in processing the requested resource.
In a further illustrative embodiment, the application broker 111 can use the application information from the URL alone or together with yet other additional information or requirements for use in selecting an instance of an application for processing requested content or selecting a domain of a network computing provider that may be authoritative to resolve the resource request. One skilled in the relevant art will appreciate that the name information and the path information is not accessible to a DNS nameserver as a part of DNS query processing. The portion of the URL including the domain and any preceding information, on the other hand, is generally referred to as the “DNS portion” of the URL.
Additionally, the modified URL can include any additional processing information (e.g., “additional information”) utilized by the application broker 111 during the request routing, including, but not limited to, content provider IDs, service plan information, file identifiers, and the like. For example, where the application information corresponds to an application identifier, the additional information may include a file identifier or service plan information. The modified URL would have the form of:

    
    
        http://additional_information.application_information.applicationbroker.com/path/resource.xxx
    
    


In another embodiment, the information associated with the application broker 111 is included in a 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:

    
    
        http://additional_information.application_information.applicationbroker.com/www.contentprovider.com/path/resource.xxx
    
    


In both of the above examples, the application information and the additional information are separated as separate labels in the modified URL. One skilled in the relevant art will appreciate that the application information and any additional information can be combined together in a single label of the modified URL. It will also be appreciated by one skilled in the relevant art that, rather than including the additional application information in the modified URL, the additional application information may be otherwise made available to the application broker and/or any DNS server in the routing process.
With reference now to FIG. 3A, after completion of the registration and resource identifier modification processes illustrated in FIG. 2, a client computing device 102 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 102 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 102 as part of the processing of the requested content.
Upon receipt of the requested content, the client computing device 102, 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. Accordingly, the first step in acquiring the content corresponds to the issuance, by the client computing device 102 (through its local DNS resolver), of a DNS query for the original URL resource identifier that results in the identification of a DNS server authoritative to the “.” and the “com” portions of the translated URL. After resolving the “.” and “com” portions of the embedded URL, the client computing device 102 then issues a DNS query for the resource URL that results in the identification of a DNS nameserver authoritative to the “.applicationbroker” portion of the embedded URL. The issuance of DNS queries corresponding to the “.” and the “com” portions of a URL are well known and have not been illustrated.
With reference now to FIG. 3B, in an illustrative embodiment, the identification of a DNS nameserver authoritative to the “applicationbroker” portion of the original URL identifies a network address, such as an IP address, of a DNS nameserver associated with the application broker 111. In one embodiment, the IP address is a specific network address unique to a DNS nameserver component of the application broker 111. In another embodiment, the IP address can be shared by one or more components of the application broker 111. In this embodiment, a further DNS query to the shared IP address utilizes a one-to-many network routing schema, such as anycast, such that a specific component of the application broker 111 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 102 to a shared IP address will arrive at a DNS nameserver component of the application broker 111 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 102 and an application broker component. It will be appreciated by one skilled in the relevant art than a number of ways exist to determine network topology distance.
With continued reference to FIG. 3B, a specific DNS nameserver 150 of the application broker 111 receives the DNS query corresponding to the original URL from the client computing device 102. Once one of the DNS nameservers in the application broker 111 receives the request, the specific DNS nameserver attempts to resolve the request. The one or more DNS nameservers of the application broker 111 can be authoritative to resolve client computing device DNS queries corresponding to the registered domain names of the application broker 111. As similarly set forth above, a DNS nameserver is considered to be authoritative to a DNS query if the DNS nameserver can resolve the query by providing a responsive IP address. Accordingly, in one illustrative embodiment, as shown in FIG. 3B, a specific DNS nameserver of the application broker 111 can resolve the DNS query by identifying an IP address of a NCC of a network computing provider 107 that will further process the request for the requested resource.
As will be described further below, in one embodiment, the application broker 111 utilizes application information, at least in part, to identify the particular instance of a NCC (and its associated IP address). In one illustrative embodiment, the application broker 111 can use the application information and any additional information in the DNS portion of the resource identifier (which is used to resolve the DNS query), or otherwise determined by the application broker 111, to return an IP address of an instance of a NCC. As similarly described above, the application information can include, without limitation, an application identifier including information pertaining to a type of hosted application for processing the requested content or a specific instance of a hosted application desired for processing the requested content, file type identifiers which can include file type information for use by the application broker in determining the appropriate type or instance of a hosted application for processing the requested content, or other client or content provider identification codes which can be used by the application broker in determining the appropriate type or instance of a hosted application for processing the requested content, and the like.
In one example, as will be further described below, where the requested content corresponds to a streaming media file, for example, the application broker 111 can use application information included in a DNS portion of the first resource identifier to select an instance of a NCC for processing the streaming media file. In one embodiment, the application information can specify file type information for the content to be processed, and the application broker 111 selects an instance of a NCC that has a data streaming application capable of processing a request for the identified file type, e.g., an MPEG or Flash media file. In another embodiment, the application information can specify a type of hosted application, e.g., an Adobe Flash server streaming application or a Real Network Helix server streaming application, to be used to process the requested content. Based on that information, the application broker 111 resolves the DNS query by identifying an instance of a NCC that corresponds to the identified type of application for processing the requested content or that can dynamically cause creation of such an instance. Still further, in another embodiment, the application information can specify a specific instance of an application, e.g., Company's Flash server, specified by a content provider for example. Based on that information, the application broker 111 then resolves the DNS query by identifying the IP address of a specific instance of a NCC that has the application required to process the requested content. Yet further, in another embodiment, the DNS portion of the first resource identifier can have a separate file type identifier which provides the file type information for use by the application broker 111 in selecting an appropriate instance of a NCC device for servicing the requested content.
Even further, the application broker 111 can also use information obtained directly from a client computing device (such as information provided by the client computing device or ISP) or indirectly (such as inferred through a client computing device's IP address) to determine an instance of a NCC. Such client computing device information can, for example, be geographic information. As will be described further below, this client computing device information together with the application information can be used to select an instance of a NCC as a function of the client computing device location. For example, in order to reduce latency and improve performance, the application broker 111 may select an instance of a NCC close to the requesting client computing device for processing a content request such as one requiring use of a streaming media application. The IP address selected by a DNS nameserver component of the application broker 111 may correspond to a specific instance of a NCC. Alternatively, the IP address can correspond to a hardware/software selection component (such as a load balancer) at a specific NCC POP for selecting a specific instance of a NCC.
Still further, for selection of an instance of a NCC, the application broker 111 can utilize additional selection information provided in the DNS portion of the resource identifier (which is used to resolve the DNS query) and/or from network computing provider 107 to the application broker 111. It will also be appreciated that the additional selection information may also be otherwise determined and/or maintained by the application broker 111. Such selection information can include information typically related to quality of service, such as computing capacity measurements of NCCs, compression rates, processing power, processing speed, bandwidth, and the like, which can be indirectly related to the cost associated with creating and/or using a particular instance of a NCC. In one embodiment, this additional selection information can be provided over a communication channel between the network computing provider 107 and the application broker 111, as generally illustrated in FIG. 2, at a variety of times. Moreover, as will be appreciated by one skilled in the relevant art, the additional selection information may be transmitted in any of a number of ways, such as upon individual requests from the application broker 111, batch processing initiated by the application broker 111 or network computing provider 107, and the like.
Continuing with reference to FIG. 3B, as an alternative to selecting a NCC upon receipt of a DNS query as described above, the application broker 111 can maintain sets of various alternative resource identifiers which correspond to DNS nameserver components associated with a NCC and which are based on prior network computing provider registration information. In this embodiment, the application broker 111 utilizes and/or obtains the application information and any additional information, as similarly set forth above, to select an alternative resource identifier. The selected alternative resource identifier can be provided by the application broker 111 to the client computing device 102 such that a subsequent DNS query on the alternative resource identifier will be processed by a DNS nameserver component within the network computing provider's network. In this embodiment, a DNS nameserver associated with the application broker 111 (directly or indirectly) is able to receive the DNS query (corresponding to the domain in the embedded resource). However, as discussed above, because the DNS nameserver does not provide a responsive IP address to the query, it is not considered authoritative to the DNS query. Instead, in this embodiment, the application broker 111 selects (or otherwise obtains) an alternative resource identifier that is intended to resolve to an appropriate DNS nameserver of a network computing provider based, at least in part, on the application information associated with the requested resource and as will be described further below. As will also be described further below, the application information and any additional information may also be used for further request routing.
In an illustrative embodiment, the alternative resource identifiers are in the form of one or more canonical name (“CNAME”) records. In one embodiment, each CNAME record identifies a domain of the network computing provider (e.g., “computingprovider.com” or “computingprovider-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 or in a previous CNAME record. In a manner similar to the information described above, each CNAME record includes the same or different application and/or additional information utilized by a receiving DNS nameserver for processing the DNS query.
In an illustrative embodiment, the application information included in the CNAME can be the same application information provided in the modified URL or additional/alternative application information obtained by the application broker 111. For example, the application information included in the CNAME can correspond to application information otherwise obtained by the application broker (directly or indirectly). As also described above, the CNAME can also include additional request routing information, (e.g., “request routing information”) utilized by the application broker 111. An illustrative CNAME record can have the form of:

    
    
        http://additional_information.application_information.applicationbroker.com/path/resources.xxxCNAMErequest_routing_information.application_information.computingprovider.com
    
    


In an illustrative embodiment, the CNAME records are generated and provided by the one or more DNS servers of the application broker 111 to direct a more appropriate DNS nameserver (or group of DNS nameservers) of a network computing provider, such as the network computing provider 107. As used in accordance with the present disclosure, appropriateness can be defined in any manner by the application broker 111 for a variety of purposes.
In the embodiment illustrated in FIG. 3B, the application broker 111 utilizes the application information, at least in part, to identify the more appropriate DNS nameserver (or group of DNS nameservers) of the network computing provider 107 or resolve the DNS query by identifying a NCC (e.g., an IP address of either a specific instance of a NCC or a load balancing or load sharing component of a NCC). Moreover, subsequently selected DNS nameservers of the network computing provider 107 may similarly utilize the same or different application information to resolve subsequently received DNS queries to identify an instance of a NCC. As described above, for any of the foregoing embodiments, the application information may be defined in a variety of ways. Additionally, although such application information can be used by different components and in different stages of the request routing process, the following section will describe how application information is used primarily with respect to the application broker 111 resolving a DNS query by providing an IP address of a NCC as a function of the application information. However, one skilled in the art and others will appreciate that other components and stages in the request routing process may similarly use such application information.
In one example, the application broker 111 may determine that requests for resources utilizing applications which receive more data from a client computing device than delivered to the client computing device should be handled by one or more NCCs positioned relatively close to the client computing device 102. One or more NCCs may be positioned at the edges of the communications network to which the client computing devices 102 are connected. Depending upon the location of a client computing device 102, some NCCs may be closer to the client computing device than others. In this context, closeness may include, but is not limited to, geographical proximity, network topology, and the like. Accordingly, the application broker 111 resolves the DNS query by selecting one or more NCCs of a network computing provider 107 closer to the client computing device 102. Accordingly, for applications which receive more data from clients than delivered out, utilizing applications at NCCs close to the clients can result in reduced latency and higher service quality. These types of applications are considered data sinks. Accordingly, in this embodiment, by providing a hosting environment for such applications that allow data from the client to be received faster through the selection of one or more NCCs close to the client computing device, overall performance can be improved.
In another example, the application broker 111 may determine that requests for resources utilizing applications which deliver more data to a client computing device than received by the application from the client computing device and which are computationally intensive should also be handled by one or more NCCs positioned relatively close to the client computing device 102. In this context, computational intensity can correspond to applications having a high processing to data source access ratio, e.g., a ratio greater than 1 or exceeding some other threshold value. By moving data delivery and processing of these types of applications closer to the client computing device, and thus the edge of the network, through selection of appropriate NCCs, the application broker 111 can distribute requests to NCCs having a higher resource availability. Accordingly, latency due to insufficient computing resources may be reduced.
In a further example, the application broker 111 may determine that requests for resources utilizing applications which are less computationally intensive and more database intensive should alternatively be handled by one or more NCCs that are close to the data source. In this context, these types of applications can correspond to applications having a processing to data source access ratio that fails to exceed a threshold, e.g., those resulting in a ratio of less than or equal to 1. Additionally, closeness may again include, but is not limited to, geographical proximity, network topology, and the like. In these instances, the application broker 111 resolves the DNS query by selecting one or more NCCs that are close to the data source. The data source may correspond, for example, to the origin server component 114 and associated storage component 116 of the content provider 104 or to a third party storage component used on behalf of the content provider 104, such as storage components 140, 144, 148 of network storage provider 110. As a result of routing this type of application in such a manner, the application broker 111 facilitates higher service quality and reduced latency in the request routing process.
As described above, in addition to the consideration of application information, the application broker 111 and/or subsequent processing components, such as components at the network computing provider 107, can utilize additional information (e.g., the “additional information”) included in the modified URL, or otherwise determined, to select a more appropriate NCC. In one aspect, the application broker 111 can utilize the additional information to select from a set of DNS nameservers identified as satisfying routing criteria including, but not limited to, financial cost to content provider 104, network performance (e.g., “internet weather”), service level criteria, resource popularity, application availability, data availability, observed behavior, etc. In another aspect, the application broker 111 can utilize the additional information to validate the NCC selected in accordance with the application information or to select an alternative DNS nameserver (or group of DNS nameservers) previously selected in accordance with the application information. In still another aspect, the application broker 111 can utilize the additional information to select a set of potentially applicable NCCs (e.g., meeting minimum service levels) and then utilize the application information to prioritize from the set of potentially applicable NCCs.
In one example, the application broker 111 can additionally attempt to direct a DNS query to DNS nameservers or resolve the DNS query to a NCC according to network performance criteria. The network performance criteria can correspond to measurements of network performance for transmitting data from the network computing provider NCCs 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 application broker 111, network data error rates, and the like.
In another example, the application broker 111 can additionally attempt to direct a DNS query to a DNS nameserver associated with a network computing provider or resolve the DNS query to a NCC according to service level criteria. The service level criteria can correspond to service or performance metrics contracted between the application broker 111 and the content provider 104. Examples of performance metrics can include latencies of data transmission between the network computing provider's POPs and the client computing devices 102, total data provided on behalf of the content provider 104 by the network computing provider's POPs, error rates for data transmissions, and the like.
In yet another example, the application broker 111 can additionally attempt to direct a DNS query to a DNS nameserver associated with a network computing provider or resolve the DNS query to a NCC according to observed behaviors. In particular, the application broker 111 can monitor past performance of the network computing provider 107 and/or NCCs of the network computing provider 107 to determine whether modifications should be made in the routing of future resource requests. It will be appreciated by one skilled in the relevant art that a variety of logic may be implemented to monitor such behavior and to update routing information based thereon.
In yet another example, the application broker 111 can attempt to direct a DNS query to a DNS nameserver associated with a network computing provider or resolve the DNS query to a NCC according to selection information criteria provided by the network computing provider 107. As similarly set forth above, such selection information can include information typically related to quality of service, such as computing capacity measurements of NCCs, compression rates, processing power, processing speed, bandwidth, and the like, which can be indirectly related to the cost associated with creating and/or using a particular instance of a NCC. This selection information can be provided over a communication channel between the network computing provider 107 and the application broker 111 at a variety of times. Moreover, as will be appreciated by one skilled in the relevant art, the selection information may be transmitted in any of a number of ways, such as upon individual requests from the application broker 111, batch processing initiated by the application broker or network computing provider, and the like.
In still another example, the application broker 111 can additionally attempt to direct a DNS query to a DNS server associated with a network computing provider or resolve the DNS query to a NCC according to cost information. The cost information can correspond to a financial cost attributable to the content provider 104 for the delivery of resources by the network computing provider 107. The financial cost may be defined in a variety of ways and can be obtained by the AM component 152 of the application broker 111, or by a management component of the network computing provider, in a variety of ways.
In another embodiment, the cost information may designate that the content provider 104 has requested that the AM component 152 of the application broker 111 select the NCC associated with the lowest current financial cost to provide the requested resource. Accordingly, the AM component 152 of the application broker 111 could obtain cost information for at least a portion of the NCCs and select the NCC of the network computing provider 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, type of application required to provide the data, etc.), anticipated data throughput volumes, current loads experienced by each NCC, and the like. For example, if a network computing provider's NCC resources are at an optimal capacity, the network computing 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 network computing provider 107 may project lower financial costs for specific NCCs 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 network computing provider. Alternatively, the financial cost information may be a set of costs associated with one or more identifiable components of each network computing provider (e.g., financial information for one or more NCCs associated with a network computing provider).
In yet another embodiment, the cost information may designate that the content provider 104 has requested that the cost associated with providing the requested resource be maintained below one or more cost thresholds or cost tiers. Accordingly, the AM component 152 of the application broker 111 could obtain financial cost information for the available NCCs and select only those NCCs with a financial cost at or below the cost thresholds. The AM component 152 of the application broker 111 could then utilize other request routing criteria to select from the selected DNS nameservers (if more than one DNS nameserver is identified) or selected in accordance with other selections methodologies (e.g., random, round robin, etc.).
In still another embodiment, the AM component 152 of the application broker 111 can utilize a determined/projected volume of request information for selecting a network computing provider, a specific DNS nameserver associated with one or more NCCs of the network computing provider, and/or a NCC of a specific provider (such as the network computing provider 107 or any other provider providing NCCs). The determined/projected volume of request information can include the total number of requests obtained by the application broker 111 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.
In a yet further embodiment, the AM component 152 of the application broker 111 can additionally utilize other content provider specified criteria for selecting a domain associated with a network computing provider and/or a specific NCC of a network computing 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.
In accordance with a specific illustrative embodiment regarding selection of a domain of a network computing provider, the application broker 111 maintains a data store that defines CNAME records for various URLs corresponding to embedded resources. If a DNS query corresponding to a particular URL matches an entry in the data store, the application broker 111 returns a CNAME record to the client computing device 102 as defined in the data store and as illustrated in FIG. 3B. 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 such an embodiment, the DNS nameserver of the application broker 111, either directly or via a network-based service, can implement additional logic, such as described above, in selecting an appropriate CNAME from a set of possible of CNAMEs.
As similarly described above, the returned CNAME can also include request routing information that is different from or in addition to the information provided in the URL/CNAME of the current DNS query. For example, if the CNAME selection is based on a service level plan selected by the content provider 104, a specific identifier associated with the selected service level plan 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 network computing provider domain different from the domain found in the original URL. For example, if the CNAME is based on a service level plan, a specific service level plan domain (e.g., “networkcomputingprovider-servicelevel1.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., http://serviceplan.networkcomputingprovider.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 application broker 111.
With reference now to FIG. 4, assume that the DNS application broker 111 has resolved the DNS query by returning the IP address of an instance of NCC 136 of NCC POP 134. Upon receipt of the IP address for the instance of NCC 136, the client computing device 102 transmits a request for the requested content to the instance of NCC 136 at the network computing provider 107. The instance of NCC 136 processes the request and the requested content obtained by NCC 136 from the network storage provider 110, for example, is then transmitted to the client computing device 102. For example, for streaming media, the instance of the NCC will begin streaming the content.
With reference now to FIG. 5, a request routine 500 implemented by the application broker 111, and by the network computing provider 107 in some embodiments, will be described. For brevity, routine 500 will be discussed further below solely with respect to the application broker 111. However, one skilled in the art and others will appreciate that routine 500 may similarly be performed by the network service provider 107 as well.
In the present illustrative embodiment, one skilled in the relevant art will also appreciate that actions/steps outlined for routine 500 may be implemented by one or many computing devices/components that are associated with the application broker 111. Accordingly, routine 500 has been logically associated as being performed by the application broker 111.
At block 502, one of the DNS nameserver components of the application broker 111 receives a DNS query corresponding to a resource identifier (the “receiving DNS nameserver). 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. Alternatively, the resource identifier can also correspond to a CNAME provided by a content provider DNS nameserver in response to a DNS query previously received from the client computing device 102. In either case, the resource identifier includes application information associated with the requested resource. In other embodiments, the resource identifier may also include additional information which can be used by the receiving DNS nameserver in processing the DNS query as further described below.
At decision block 504, a test is conducted to determine whether the current receiving DNS nameserver is authoritative to resolve the DNS query. In one 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. For example, the receiving DNS nameserver may maintain one or more CNAMEs that define various application alternatives for request routing processing. In this embodiment, the receiving DNS nameserver utilizes the application information obtained in block 702 to select the appropriate CNAME. As similarly set forth above, in other embodiments, in addition to the application information, the receiving DNS nameserver can utilize additional information or request routing information also provided in the resource identifier to select the appropriate CNAME. Alternatively, the receiving DNS nameserver may select a CNAME by obtaining further application information or additional information based on the resource identifier, but not included in the resource identifier. Accordingly, as previously discussed, the selection of the appropriate CNAME will depend at least in part on the application information processed by the application broker 111, whether obtained directly and/or indirectly from the resource identifier associated with the DNS query. Alternative or additional methodologies may also be practiced to determine whether the DNS nameserver is authoritative.
At decision block 504, if the current receiving DNS nameserver is authoritative (including a determination that the same DNS nameserver will be authoritative for subsequent DNS queries), the current receiving DNS nameserver resolves the DNS query by returning the IP address of an instance of a NCC at block 506. Alternatively, as described above, the IP address can correspond to a hardware/software selection component (such as a load balancer) at a specific NCC POP for selecting a specific instance of a NCC. In either case, the receiving DNS nameserver selects an IP address as a function of the application information obtained directly and/or indirectly from the resource identifier associated with the DNS query. Additionally, as discussed above, the receiving DNS nameserver can identify an IP address to resolve the DNS query by also utilizing additional information or request routing information obtained from the resource identifier associated with the DNS query or otherwise obtained.
Alternatively, if at decision block 504 the receiving DNS nameserver component is not authoritative, at block 508, the DNS nameserver component selects and transmits an alternative resource identifier. As described above, the DNS nameserver component can utilize a data store to identify an appropriate CNAME as a function of the current DNS query, including at least in part the application information in the DNS portion of the URL or CNAME. Additionally, the DNS nameserver component can also implement additional logical processing to select from a set of potential CNAMES. At block 510, different DNS nameserver components of a network computing provider 107 receive a DNS query corresponding to the CNAME. The routine 500 then returns to decision block 504 and continues to repeat as appropriate.
Accordingly, in the routine 500, the receiving DNS nameserver selects either an IP address of a NCC or a CNAME, at least in part, as a function of application information provided in a DNS portion of the resource identifier associated with the DNS query. As an example, the application information in the DNS portion of the resource identifier can specify information associated with the file type of the requested resource, an application type, or specific instance of an application for processing the requested resource. As further set forth above, a number of other factors may additionally be taken into consideration for selecting the appropriate NCC or CNAME for further servicing the resource request.
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 invention. 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 scope of variations to the present disclosure.
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 and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/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 and/or steps are included or are to be performed in any particular embodiment.
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 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.
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.

## Claims

1. A system for processing resource requests comprising:
a DNS nameserver component associated with an application broker, wherein the DNS nameserver component receives a DNS query from a client computing device, wherein the DNS query corresponds to a requested resource associated with a first resource identifier including application information regarding the requested resource, wherein the application broker manages content processing on behalf of a content provider, wherein the first resource identifier further includes information identifying the application broker, and wherein the DNS nameserver component includes one or more computing devices and is operable to:
parse the first resource identifier so as to obtain the application information regarding the requested resource;
obtain a second resource identifier based at least in part on a portion of the application information parsed from the first resource identifier, wherein the second resource identifier resolves to one of:
a domain of a network computing provider selected as a function of a location associated with the client computing device if a ratio of data received by an application for processing the requested resource to data delivered out of the application exceeds a first threshold, wherein the network computing provider is different from the application broker;
a domain of a network computing provider selected as a function of a location associated with the client computing device if a ratio of a measure of resource utilization to data received by the application from a source exceeds a second threshold, wherein the network computing provider is different from the application broker; and
a domain of a network computing provider selected as a function of a location associated with a storage component maintaining the requested resource if a ratio of a measure of resource utilization to data received by the application from a source fails to exceed a third threshold, wherein the network computing provider is different from the application broker; and

transmit the second resource identifier to the client computing device.

2. The system as recited in claim 1 further comprising:
a second DNS nameserver component that receives, from the client computing device, a subsequent DNS query corresponding to the second resource identifier provided by the application broker, wherein the second DNS nameserver component corresponds to a network computing provider, and wherein the second DNS nameserver component is operable to:
resolve the subsequent DNS query, at the second DNS server, to identify an IP address corresponding to a network computing component for processing and providing content associated with the original resource request; and
transmit the IP address corresponding to the network computing component to the client computing device.

3. The system as recited in claim 2, wherein the second resource identifier includes additional routing criteria different from the first resource identifier, wherein the additional routing criteria includes at least one of service level routing criteria, geographic routing criteria, network performance routing criteria, financial cost routing criteria, resource popularity information, observed behavior, and content provider specified routing criteria.

4. The system as recited in claim 3, wherein the second DNS nameserver is further operable to parse the second resource identifier so as to obtain the additional routing criteria regarding the requested resource, wherein the second DNS nameserver resolves the subsequent DNS query to identify an IP address corresponding to a network computing component as a function of the parsed additional routing criteria.

5. The system as recited in claim 1, wherein the first resource identifier includes a first portion with DNS information and a second portion with path information.

6. The system as recited in claim 5, wherein the first portion of the first resource identifier includes the application information.

7. The system as recited in claim 1, wherein the DNS nameserver component obtains the second resource identifier additionally based on at least one of service level routing criteria, geographic routing criteria, network performance routing criteria, financial cost routing criteria, resource popularity information, observed behavior, and content provider specified routing criteria.

8. The system as recited in claim 7, wherein network performance routing criteria includes network data transfer latencies.

9. The system as recited in claim 1, wherein the first and second resource identifiers are Uniform Resource Locators (URLs).

10. A method for request routing comprising:
obtaining a DNS query from a client computing device at a DNS server, wherein the DNS query corresponds to a requested resource associated with a first resource identifier, wherein the DNS server corresponds to an application broker, and wherein the first resource identifier includes information identifying the application broker;
determining that the first resource identifier is associated with an alternative resource identifier as a function of application information regarding the requested resource, wherein the application information is included in the first resource identifier; and
transmitting the alternative resource identifier to the client computing device, wherein the alternative resource identifier includes information for causing a DNS query to resolve to a domain corresponding to a network computing provider and supplemental request routing information not included in the first resource identifier.

11. The method of claim 10 further comprising:
obtaining a subsequent DNS query from the client computing device at a second DNS server, wherein the subsequent DNS query corresponds to the alternative resource identifier provided by the application broker and wherein the second DNS server corresponds to the network computing provider;
resolving the subsequent DNS query, at the second DNS server, to identify a network computing component for processing and providing content associated with the original resource request; and
transmitting information identifying the network computing component to the client computing device.

12. The method as recited in claim 11, wherein resolving the subsequent DNS query to identify a network computing component comprises identifying an IP address of a network computing component as a function of the supplemental request routing information included in the alternative resource identifier.

13. The method as recited in claim 12, wherein the supplemental request routing information includes one of service level routing criteria, geographic routing criteria, network performance routing criteria, financial cost routing criteria, observed behavior, and content provider specified routing criteria.

14. The method as recited in claim 10, wherein first resource identifier corresponds to a uniform resource locator such that the DNS query resolves to a domain corresponding to the network computing provider.

15. The method as recited in claim 10, wherein the alternative resource identifier corresponds to a canonical name record identifier.

16. The method as recited in claim 10, wherein the network computing component comprises an application for processing the requested resource.

17. The method as recited in claim 10, wherein the network computing component is operable to dynamically cause the creation of an instance of a virtual machine for processing the requested resource.

18. The method as recited in claim 10, wherein the application information includes information associated with a file type of the requested resource.

19. The method as recited in claim 10, wherein the application information includes information associated with a type of application for processing the requested resource.

20. The method as recited in claim 10, wherein the application information includes information identifying an instance of an application for processing the requested resource.

21. The method as recited in claim 10 further comprising obtaining, at the DNS server, information corresponding to the client computing device associated with the DNS query, wherein the information corresponding to the client computing device is associated with a geographic location of the client computing device and wherein selecting an alternative resource identifier is further based on information associated with a geographic location of the client computing device.

22. The method as recited in claim 10 further comprising determining, at the DNS server, information corresponding to a storage location of the requested resource associated with the DNS query, wherein selecting an alternative resource identifier is further based on information associated with the storage location of the requested resource.

23. The method as recited in claim 10 further comprising determining, at the DNS server, information corresponding to latency information associated with the DNS query, wherein selecting an alternative resource identifier is further based on the latency information.

24. The method as recited in claim 10, wherein the alternative resource identifier resolves to a domain of a network computing provider selected as a function of a location associated with the client computing device if a ratio of data received by an application for processing the requested resource to data delivered out of the application exceeds a first threshold.

25. The method as recited in claim 10, wherein the alternative resource identifier resolves to a domain of a network computing provider selected as a function of a location associated with the client computing device if a ratio of a measure of resource utilization to data received by the application from a source exceeds a second threshold.

26. The method as recited in claim 10, wherein the alternative resource identifier resolves to a domain of a network computing provider selected as a function of a location associated with a storage component maintaining the requested resource if a ratio of a measure of resource utilization to data received by the application from a source fails to exceed a third threshold.

27. A method for request routing comprising:
obtaining a DNS query from a client computing device at a DNS server, wherein the DNS query corresponds to a requested resource associated with a first resource identifier, wherein the DNS server corresponds to an application broker, and wherein the first resource identifier includes information identifying the application broker;
selecting a network computing component for processing the requested resource from a plurality of network computing components based on application information included in the first resource identifier; and
transmitting information identifying the selected network computing component from the DNS server to the client computing device.

28. The method as recited in claim 27, wherein the network computing component comprises an application for processing the requested resource.

29. The method as recited in claim 27, wherein the network computing component is operable to dynamically cause the creation of an instance of a virtual machine for processing the requested resource.

30. The method as recited in claim 27, wherein the application information comprises identification of a file type of the requested resource and wherein a network computing component is selected at the DNS server based on the file type.

31. The method as recited in claim 27, wherein the application information comprises identification of a type of application for processing the requested resource and wherein a network computing component is selected at the DNS server based on the application type.

32. The method as recited in claim 27, wherein the application information includes identification of an instance of an application for processing the requested resource and wherein a network computing component is selected at the DNS server based on the application instance.

33. The method as recited in claim 27 further comprising determining, at the DNS server, additional information for selecting the network computing component, wherein the additional information includes at least one of service level routing criteria, geographic routing criteria, network performance routing criteria, financial cost routing criteria, observed behavior, and content provider specified routing criteria.

34. The method as recited in claim 27 further comprising obtaining, at the DNS server, information corresponding to the client computing device associated with the DNS query, wherein the information corresponding to the client computing device is associated with a geographic location of the client computing device and wherein selecting a network computing component is further based on information associated with a geographic location of the client computing device.

35. The method as recited in claim 27 further comprising determining, at the DNS server, information corresponding to a storage location of the requested resource associated with the DNS query, wherein selecting a network computing component is further based on information associated with the storage location of the requested resource.

36. The method as recited in claim 27, wherein the network computing component is further selected as a function of a location associated with the client computing device if a ratio of data received by an application for processing the requested resource to data delivered out of the application exceeds a first threshold.

37. The method as recited in claim 27, wherein the network computing component is further selected as a function of a location associated with the client computing device if a ratio of a measure of resource utilization to data received by the application from a source exceeds a second threshold.

38. The method as recited in claim 27, wherein the network computing component is further selected as a function of a location associated with a storage component maintaining the requested resource if a ratio of a measure of resource utilization to data received by the application from a source fails to exceed a third threshold.