Content distribution system using an alternative domain name system (DNS) and content servers

• US 7,693,959 B2
• Filed: 09/01/2006
• Issued: 04/06/2010
• Est. Priority Date: 07/14/1998
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Lewin, Daniel M., Leighton, F. Thomson
• Primary Examiner(s): Vaughn, Jr.; William C
• Assistant Examiner(s): Shingles; Kristie D
• Application Number:
  US11/515,171
• Publication Number:
  US 20070005689A1
• Time in Patent Office: 1,313 Days
• Field of Search: 709/217, 709/219, 709/229, 709/238
• US Class Current: 709/217
• 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 computer-implemented method of delivering text, graphics, images, downloads, audio or video on behalf of multiple content providers, comprising:

operating content delivery network (CDN) content servers in multiple locations, each location with connectivity to one or more networks;

operating multiple CDN name servers;

receiving a first domain name service (DNS) query at a first CDN name server, the first DNS query including a data string of the form “

string1 string2 string3”

, where;

string3 is a generic top level domain (gTLD),

string2 is separated from string3 by a period and is a name maintained by a service provider that operates the CDN content servers and the CDN name servers, and

string1 is separated from string2 by a period and comprises one or more sub-strings, where each sub-string is comprised of one of;

letters, numbers, and combinations of letters and numbers, and any pair of sub-strings in string 1 are separated by a period;

having the first CDN name server respond to the first DNS query by sending a response that includes a first set of one or more IP addresses, where a first end user request for content directed to one of the IP addresses of the first set causes the service provider to deliver the content to a first end user from a first CDN content server;

receiving a second DNS query at a second CDN name server, the second DNS query also including the same data string that is received by the first CDN name server; and

having the second CDN name server respond to the second DNS query by sending a response that includes a second set of one or more IP addresses, wherein a second end user request for content directed to one of the IP addresses of the second set causes the service provider to deliver the content to a second end user from a second CDN content server;

the second set of one or more IP addresses differing from the first set of one or more IP addresses based on where the first and second DNS queries originate.

2. The method as described in claim 1 wherein the CDN name servers are deployed at the multiple locations, and wherein the first and second DNS queries are received from respective first and second local DNS name servers.

3. The method as described in claim 2 wherein the first CDN name server is closer to the first local DNS name server than is the second CDN name server.

4. The method as described in claim 1 wherein the first CDN content server is closer to the first end user than is the second CDN content server.

5. The method as described in claim 2 wherein the first CDN content server is closer to the first local DNS name server than is the second CDN content server.

6. The method as described in claim 1 wherein the first CDN content server is reachable through an IP address in the first set of IP addresses.

7. The method as described in claim 6 wherein the IP address of the first CDN content server is among the first set of IP addresses.

8. The method as described in claim 1 wherein a location of the multiple locations is a network exchange point or a network access point.

9. The method as described in claim 1 wherein the multiple locations are part of a network associated with the service provider.

10. The method as described in claim 1 wherein the multiple CDN name servers are an authority for string2.string3.

11. The method as described in claim 1 wherein the portion string2.string3 of the data string is used by the service provider for two or more content providers that use the CDN content servers to deliver their respective content.

12. The method as described in claim 1 wherein the content requested by the first end user and the content requested by the second end user are one of the following:

(a) the same content, (b) different content from the same content provider, and (c) different content from different content providers.

13. The method as described in claim 1 wherein a sub-string of string1 is associated with one or more CDN name servers that comprise a level of a DNS hierarchy.

14. The method as described in claim 13 wherein a first sub-string of string1 is associated with one or more CDN name servers in a first level of a DNS hierarchy, and wherein a second substring of string 1 is associated with one or more name servers in a second level of the DNS hierarchy.

15. The method as described in claim 4 wherein the first CDN content server is not overloaded.

16. The method as described in claim 15 wherein the first CDN content server is likely to have the content requested by the first end user.

17. The method as described in claim 5 wherein the first CDN content server is not overloaded.

18. The method as described in claim 17 wherein the first CDN content server is likely to have the content requested by the first end user.

19. The method as described in claim 1 wherein the content requested by the first end user is associated with the data string.

20. The method as described in claim 19 wherein the data string is located in a Uniform Resource Locator (URL) for the content requested by the first end user.

21. The method as described in claim 20 wherein the URL includes, in addition to the data string, a content provider domain name.

22. The method as described in claim 21 where the data string is positioned in front of the content provider domain name within the URL.

23. The method as described in claim 22 wherein the content provider domain name is retained in the URL to facilitate retrieval of the content by a CDN content server.

24. The method as described in claim 23 wherein the content provider domain name is used to retrieve the content from a content provider server upon a given occurrence.

25. The method as described in claim 24 wherein the given occurrence is that the content is not available from the CDN content server.

26. The method as described in claim 1 where the data string includes a value that encodes information about the content.

27. The method as described in claim 1 where the data string includes a value that identifies a type of content.

28. The method as described in claim 1 wherein the content requested by the first end user is an embedded object.

29. The method as described in claim 28 wherein the embedded object is contained in a markup language page.

30. The method as described in claim 1 further including serving the content requested by the first end user from the first CDN content server.

31. The method as described in claim 30 wherein the content requested by the first end user is one of:

an object, a media stream, and a piece of software.

32. The method as described in claim 30 wherein the object is part of a web page.

33. The method as described in claim 1 wherein the data string is a virtual global host name.

34. A computer-implemented method of content delivery operative in a content delivery network (CDN) for multiple content providers, the CDN comprising collections of CDN content servers, and a CDN name service having multiple CDN name servers, comprising:

receiving, at the CDN name service, first and second DNS queries, wherein the first DNS query includes a name that points to the CDN, wherein the second DNS query also includes the name, wherein the name includes a character string having a first portion, a second portion, and a third portion, wherein the first portion is a generic top level domain, and the second portion is separated from the first portion by a period and is an identifier maintained by a service provider that operates the CDN name service; and

returning, by the CDN name service, a response to each of the first and second DNS queries, where a response to the first DNS query is provided by a first CDN name server and leads to a first subset of CDN content servers, and where a response to the second DNS query is provided by a second CDN name server and leads to a second subset of CDN content servers, the second CDN name server being distinct from the first CDN name server, where information within the responses to the first and second DNS queries varies based on where the respective first and second DNS queries originate.

35. The method as described in claim 34 wherein the first DNS query results from a request for a first content object, and the second DNS query results from a request for a second content object, wherein the first and second content objects are one of:

(a) the same content, (b) different content from the same content provider, and (c) different content from different content providers.

36. The method as described in claim 34 wherein the name that points to the CDN is a virtual global host name.

37. The method as described in claim 34 wherein the first portion of the character string is an end portion, the second portion of the character string is a next-to-end portion, and the third portion of the character string is a next portion, where the third portion is separated from the second portion by a period.

38. The method as described in claim 34 wherein the third portion includes information associated with one or more CDN name servers of the CDN name service.

39. The method as described in claim 38 wherein the one or more CDN name servers of the CDN name service identified by the information comprise a level of a DNS hierarchy.

40. The method as described in claim 39 wherein the DNS hierarchy includes first and second levels.

41. The method as described in claim 34 wherein the first DNS query is received from a first local name server at a first location, and the second DNS query is received from a second local name server at a second location, where the second location is distinct from the first location.

42. The method as described in claim 41 where the response to the first DNS query comprises one or more IP addresses.

43. The method as described in claim 42 wherein the one or more IP addresses are IP addresses associated with the first subset of CDN content servers.

44. The method as described in claim 43 wherein the IP addresses associated with the first subset of CDN content servers include an IP address associated with a CDN content server that is co-located with the first CDN name server.

45. The method as described in claim 44 wherein a content request includes the name that points to the CDN.

46. The method as described in claim 34 wherein the name that points to the CDN is in a Uniform Resource Locator (URL) for a content object of a content provider.

47. The method as described in claim 46 wherein the URL also includes information associated with the content provider that publishes the content object.

48. The method as described in claim 47 wherein the information is a content provider domain name.

49. The method as described in claim 48 where the name that points to the CDN is positioned in front of the content provider domain name within the URL.

50. The method as described in claim 34 wherein the CDN name service comprises the first CDN name server and the second CDN name server, the first CDN name server being located in proximity to the first subset of CDN content servers, the second CDN name server being located in proximity to the second subset of CDN content servers.

51. The method as described in claim 50 wherein the first and second CDN name servers are located in a second level of a DNS hierarchy having at least first and second levels.

52. The method as described in claim 51 wherein the first level of the DNS hierarchy includes at least one other CDN name server that receives the first query and, in response, returns an IP address or the first or second CDN name server in the second level.

53. The method as described in claim 34 where the name that points to the CDN includes a value that encodes information about a content object.

54. The method as described in claim 34 where the name that points to the CDN includes value that identifies a type of content object.

55. The method as described in claim 34 further including serving a content object from a content server in either the first subset of CDN content servers or the second subset of CDN content servers.

56. The method as described in claim 55 wherein the content object is one of:

a web object, a media stream, and a piece of software.

57. The method as described in claim 56 wherein the web object is part of a web page.

58. A system for content delivery operated by a content delivery network (CDN) service provider for multiple content providers, comprising:

a plurality of CDN content servers organized into sets; and

a CDN name service having a set of name servers, the CDN name service receiving first and second DNS queries and returning a response to each of the first and second DNS queries;

where the first DNS query includes a name that points to the CDN, the name of the form “

string 1 string2 string3”

, where;

string3 is a generic top level domain (gTLD),

string2 is separated from string3 by a period and is a name maintained by the CDN service provider, and

string 1 is separated from string2 by a period and comprises one or more sub-strings, where each sub-string is comprised of one of;

letters, numbers, and combinations of letters and numbers, and any pair of sub-strings in string1 are separated by a period;

where the second DNS query also includes the name;

where a response to the first DNS query leads to a first subset of CDN content servers;

where a response to the second DNS query leads to a second subset of CDN content servers; and

where information within the responses to the first and second DNS queries varies based on where the respective first and second DNS queries originate.