Content delivery network using edge-of-network servers for providing content delivery to a set of participating content providers

• US 6,553,413 B1
• Filed: 06/28/2000
• Issued: 04/22/2003
• Est. Priority Date: 07/14/1998
• Status: Expired due to Term

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Lewin, Daniel M., Leighton, F. Thomson
• Primary Examiner(s): Wiley, David
• Assistant Examiner(s): Baugh, April L
• Application Number:
  US09/604,878
• Time in Patent Office: 1,028 Days
• Field of Search: 395/800, 709/200, 709/217, 709/218, 709/219
• US Class Current: 709/219
• CPC Class Codes: G06F 16/957 Browsing optimisation, e.g. caching or content distillation
• CPC Class Codes: G06F 16/9574 of access to content, e.g. by caching
• CPC Class Codes: G06F 16/958 Organisation or management of web site content, e.g. publishing, maintaining pages or automatic linking
• CPC Class Codes: H04L 61/2514 between local and global IP addresses
• CPC Class Codes: H04L 61/30 Managing network names, e.g. use of aliases or nicknames name-to-address mapping H04L61/45
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/101 based on network conditions
• CPC Class Codes: H04L 67/1019 Random or heuristic server selection
• CPC Class Codes: H04L 67/1021 based on client or server locations
• CPC Class Codes: H04L 67/1023 based on a hash applied to IP addresses or costs
• CPC Class Codes: H04L 67/1029 using data related to the state of servers by a load balancer
• CPC Class Codes: H04L 67/1034 Reaction to server failures by a load balancer
• CPC Class Codes: H04L 67/1095 Replication or mirroring of data, e.g. scheduling or transport for data synchronisation between network nodes
• CPC Class Codes: H04L 67/289 Intermediate processing functionally located close to the data consumer application, e.g. in same machine, in same home or in same sub-network
• CPC Class Codes: H04L 67/563 Data redirection of data network streams
• CPC Class Codes: H04L 67/567 : Integrating service provisioning from a plurality of service providers
• CPC Class Codes: H04L 67/568 : Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: H04L 9/40 : Network security protocols

Abstract

The present invention is a network architecture or framework that supports hosting and content distribution on a truly global scale. The inventive framework allows a Content Provider to replicate and serve its most popular content at an unlimited number of points throughout the world. The inventive framework comprises a set of servers operating in a distributed manner. The actual content to be served is preferably supported on a set of hosting servers (sometimes referred to as ghost servers). This content comprises HTML page objects that, conventionally, are served from a Content Provider site. In accordance with the invention, however, a base HTML document portion of a Web page is served from the Content Provider'"'"'s site while one or more embedded objects for the page are served from the hosting servers, preferably, those hosting servers near the client machine. By serving the base HTML document from the Content Provider'"'"'s site, the Content Provider maintains control over the content.

Claims

1. A method of content delivery wherein participating content providers identify content to be delivered by a content delivery network service provider from a set of content servers associated with the content delivery network service provider, wherein a given object of a participating content provider is associated with a Uniform Resource Locator (URL) that includes, in addition to a filename, an alphanumeric string that is resolvable in a domain name system (DNS) associated with the content delivery network service provider, the domain name system including a set of name servers, comprising:

during a first DNS query performed on a first portion of the alphanumeric string, selecting a given one of the name servers in the domain name system associated with the content delivery network service provider;

during a second DNS query performed at the given one of the name servers in the domain name system associated with the content delivery network service provider and on a second portion of the alphanumeric string together with the first portion, identifying a given server from the set of content servers associated with the content delivery network service provider;

at the given server, receiving a request for the given object; and

in response to the request, serving the given object from the given server.

2. The method as described in claim 1 wherein the domain name system associated with the content delivery network service provider selects the given one of the name servers as a function of where the first DNS query originates.

3. The method as described in claim 1 wherein the given server is identified from the set of content servers associated with the content delivery network service provider as a function of where the first DNS query originates and Internet traffic conditions.

4. The method as described in claim 1 wherein the second portion of the alphanumeric string includes a value identifying a virtual content bucket in which the given object is likely to be associated.

5. The method as described in claim 1 wherein the first and second DNS queries are performed without reference to the filename the given object.

6. The method as described in claim 1 further including the step of caching the given object at the server associated with the IP address for a given time to live (TTL) so that the given object is available for delivery in response to a new request received at the server associated with the IP address.

7. The method as described in claim 1 wherein the given object of the participating content provider is an embedded object in a markup language page.

8. A method of content delivery wherein participating content providers identify content to be delivered by a content delivery network service provider from a set of content servers associated with the content delivery network service provider, wherein a given object of a participating content provider is associated with a 12293:

10 PATENT Uniform Resource Locator (URL) that includes, in addition to a filename, an alphanumeric string, comprising;

having the content delivery network service provider establish a domain name system (DNS) having authority to resolve the alphanumeric strings in the URLs of the objects identified by the participating content providers, the content delivery network service provider'"'"'s domain name system having one or more DNS levels, wherein at least one DNS level comprises a set of one or more name servers;

for each of one or more participating content providers, delivering a given object on behalf of the participating content provider, wherein the given object is delivered by the following steps;

responsive to a DNS query, selecting a given one of the name servers in the content delivery network service provider'"'"'s domain name system;

at the given one of the name servers, resolving the alphanumeric string to an IP address, wherein the alphanumeric string is resolved without reference to the filename for the given object;

at a server associated with the IP address, the server being one of the set of content servers, receiving a request for the given object, the request having the filename associated therewith;

from the server, serving the given object; and

caching the given object at the server so that the given object is available for delivery from the server for a given time period in the event that a new DNS query to resolve the alphanumeric string is received at the domain name system and is resolved to the IP address of the server.

9. The method as described in claim 8 wherein the given one of the name servers is selected as a function of where the DNS query originates.

10. The method as described in claim 8 wherein the server associated with the IP address is identified as a function of where the DNS query originates and Internet traffic conditions.

11. The method as described in claim 8 wherein the given object of the participating content provider is an embedded object in a markup language page.

12. The method as described in claim 8 wherein the request includes a value for use at the server associated with the IP address in determining whether a version of the given object is fresh.

13. The method as described in claim 8 wherein the DNS query is initiated from an end user local name server.

14. Apparatus for use in a content delivery network wherein participating content providers identify content to be delivered by a content delivery network service provider from a set of content servers in the content delivery network, wherein a given object of a participating content provider is associated with a Uniform Resource Locator (URL) that includes, in addition to a filename, an alphanumeric string that is resolvable in a domain name system associated with the content delivery network service provider, the domain name system associated with the content delivery network service provider including a set of name servers, comprising:

domain name service (DNS) code for resolving, to an IP address, a DNS query identifying the alphanumeric string, wherein the IP address is associated with a content server selected from the set of content servers;

wherein the domain name service (DNS) code comprises a first set of code executing on a first processor for resolving a first portion of the alphanumeric string to identify a given one of the set of name servers, and a second set of code executing on the given one of the set of name servers for resolving a second portion of the alphanumeric string, together with the first portion of the alphanumeric string, to the IP address.

15. The apparatus as described in claim 14 wherein the DNS code resolves the DNS query as a function of a location of an entity that initiates the DNS query.

16. The apparatus as described in claim 14 wherein the DNS code resolves the DNS query as a function of a location of an entity that initiates the DNS query and given network traffic conditions.

17. The apparatus as described in claim 14 wherein the given object is an embedded object in a markup language page.

18. A method of content delivery wherein participating content providers identify content to be delivered by a content delivery network service provider from a set of content servers associated with the content delivery network service provider, wherein a given object of a participating content provider is associated with a Uniform Resource Locator (URL) that includes, in addition to a filename, an alphanumeric string, comprising:

having the content delivery network service provider establish a domain name system (DNS) having authority to resolve the alphanumeric strings in the URLs of the objects identified by the participating content providers, the content delivery network service provider'"'"'s domain name system having one or more DNS levels, wherein at least one DNS level comprises a set of one or more name servers;

for each of one or more participating content providers, delivering a given object on behalf of the participating content provider, wherein the given object is delivered by the following steps;

responsive to a DNS query, selecting a given one of the name servers in the content delivery network service provider'"'"'s domain name system as a function of where the DNS query originates;

at the given one of the name servers, resolving the alphanumeric string to an IP address, wherein the alphanumeric string is resolved without reference to the filename for the given object;

at a server associated with the IP address, the server being one of the set of content servers, receiving a request for the given object, the request having the filename associated therewith; and

from the server, serving the given object.

19. The method of content delivery as described in claim 18 wherein the step of delivering a given object on behalf of the participating content provider further includes the step of:

caching the given object at the server so that the given object is available for delivery from the server at a later time in the event that a new DNS query to resolve the alphanumeric string is received at the domain name system and is resolved to the IP address of the server.

20. A method of content delivery wherein participating content providers identify content to be delivered by a content delivery network service provider from a set of content servers associated with the content delivery network service provider, wherein a given object of a participating content provider is associated with an alphanumeric string, comprising:

having the content delivery network service provider establish a domain name system (DNS) having authority to resolve the alphanumeric strings associated with the objects identified by the participating content providers, the content delivery network service provider'"'"'s domain name system having one or more DNS levels, wherein at least one DNS level comprises a set of one or more name servers;

for each of one or more participating content providers, delivering a given object on behalf of the participating content provider, wherein the given object is delivered by the following steps;

responsive to a DNS query received from a client local name server, selecting a given one of the name servers in the content delivery network service provider'"'"'s domain name system;

at the given one of the name servers, resolving the alphanumeric string to an IP address, wherein the alphanumeric string is resolved without reference to the filename for the given object;

at a server associated with the IP address, the server being one of the set of content servers, receiving a request for the given object, the request having the filename associated therewith; and

from the server, serving the given object.

21. The method as described in claim 20 wherein the server associated with the IP address is identified as a function of where the DNS query originates.

22. The method as described in claim 20 wherein the server associated with the IP address is identified as a function of where the DNS query originates and Internet traffic conditions.