Handling long-tail content in a content delivery network (CDN)

• US 8,930,538 B2
• Filed: 03/21/2009
• Issued: 01/06/2015
• Est. Priority Date: 04/04/2008
• Status: Active Grant

• Current Assignee: Level 3 Communications LLC (Lumen Technologies, Inc.)
• Original Assignee: Level 3 Communications LLC (Lumen Technologies, Inc.)
• Inventors: Fullagar, David, Newton, Christopher, Lipstone, Laurence R.
• Primary Examiner(s): DAILEY, THOMAS J
• Application Number:
  US12/408,681
• Publication Number:
  US 20090254661A1
• Time in Patent Office: 2,117 Days
• Field of Search: 709/226, 709/219, 709/223
• US Class Current: 709/226
• CPC Class Codes: H04L 67/563 Data redirection of data network streams
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: H04N 21/222 Secondary servers, e.g. proxy server, cable television Head-end provisioning of proxy services in data packet switching networks H04L67/56
• CPC Class Codes: H04N 21/23106 involving caching operations prefetching while addressing of a memory level in which the access to the desired data or data block requires associative addressing means within memory systems or architectures G06F12/0862; caching at an intermediate stage in a data network H04L67/568
• CPC Class Codes: H04N 21/25891 being end-user preferences retrieval of video data in a video database based on user preferences G06F16/739; arrangements for recognizing users' preferences H04H60/46; user profiles in network data switching protocols H04L67/306; processing of user preferences or user profiles in wireless networks H04W8/18
• CPC Class Codes: H04N 21/472 End-user interface for requesting content, additional data or services; End-user interface for interacting with content, e.g. for content reservation or setting reminders, for requesting event notification, for manipulating displayed content end-user interfaces for retrieving video data from a database G06F16/739; network services for supporting unicast streaming H04L65/612
• CPC Class Codes: H04N 7/17354 in an intermediate station common to a plurality of user terminals

Abstract

A content delivery network has at least a first tier of servers. A content delivery method includes, at a first server in the first tier of servers, obtaining a request from a client for a resource. If the resource is available at the first server or at a peer of the first server, then the resource is served to the client from the first server. Otherwise, it is determined whether the resource is popular, and if the resource is determined to be popular, then the first server obtains the resource and the first server serves the resource to the client. If the resource is determined not to be popular, the client is directed to a second server, not in the first tier of servers, and the second server serves the resource to the client. The second server may be in a second tier of servers or it may be an origin server.

Claims

1. A method of content delivery in a content delivery network comprising at least a first tier of servers, the method comprising:

(A) at a first server in said first tier of servers, obtaining a request from a client for a resource;

(B) if said resource is available at said first server or at a peer of said first server, serving the resource to the client from the first server;

(C) otherwise, if said resource is not available at said first server or at a peer of said first server, determining whether said resource is to be served based on popularity of the resource; and

(D) when a determination is not made that said resource is to be served based on popularity of the resource, obtaining the resource at said first server and serving the resource to the client from the first server; and

(E) when the determination is made that said resource is to be served based on popularity of the resource,

(E)(1) determining whether said resource is popular, and

(E)(2) if the resource is determined to be popular, then said first server obtaining said resource and said first server serving the resource to the client, otherwise,

(E)(3) if the resource is determined not to be popular, directing said client to a second server, said second server not in said first tier of servers, and

(E)(4) said second server serving the resource to the client.

2. The method of claim 1 wherein the network further comprises a second tier of servers, distinct from said first tier of servers, and wherein said second server is in said second tier of servers.

3. The method of claim 1 wherein the second server is a content provider'"'"'s origin server.

4. The method of claim 1 wherein the step of determining whether said resource is popular comprises:

determining whether a current popularity value for said resource exceeds a first predetermined popularity threshold.

13. The method of claim 1 wherein determining whether said resource is popular is based at least in part on a dynamic measure of popularity of the resource.

14. The method of claim 1 wherein the resource is part of an object, and wherein determining whether said resource is popular is based at least in part on whether the resource is an initial part of the object.

15. The method of claim 1 wherein the resource is part of an object, and wherein determining whether said resource is popular is based at least in part on whether the resource is for another part of the object, the initial part of the object having already been served to the client.

16. The method of claim 1 wherein the determining whether said resource is popular is determined, at least in part, using one or more popularity servers.

17. The method of claim 1 wherein the first server determines whether said resource is popular based on information obtained from a popularity service.

18. The method of claim 17 wherein the popularity service runs on a popularity server.

19. The method of claim 18 wherein the popularity server maintains information on relative popularity of content being served.

20. The method of claim 19 wherein the popularity server maintains information on relative popularity of content being served in a region comprising the first server.

21. The method of claim 1 wherein determining whether said resource is popular comprises:

determining a relative popularity said resource.

22. The method of claim 21 wherein determining whether said resource is popular comprises:

determining a relative popularity said resource in a region comprising the first server.

27. The method of claim 1 wherein the act of determining whether said resource is to be served based on popularity of the resource comprises:

determining whether said resource is designated to be served based on popularity of the resource.

5. A method of content delivery in a content delivery network comprising at least a first tier of servers, the method comprising:

(A) at a first server in said first tier of servers, obtaining a request from a client for a resource;

(B) if said resource is not available at said first server or at a peer of said first server, then selectively redirecting the request from the client to a second server in the network, said second server being distinct from said first tier of servers, said redirecting being based, at least in part, on whether or not said resource is to be served based on popularity of the resource and on a current popularity value for said resource.

6. The method of claim 5 wherein the network further comprises a second tier of servers, said servers in said second tier being distinct from said servers in said first tier, and wherein said second server is in said second tier of servers.

7. The method of claim 5 wherein the network further comprises a second tier of servers, said servers in said second tier being distinct from said servers in said first tier, and wherein said second server is an origin server.

23. The method of claim 5 wherein the current popularity value for the resource is based at least in part on a dynamic measure of popularity of the resource.

28. The method of claim 5 wherein whether or not said resource is to be served based on popularity of the resource is based at least in part on whether or not said resource is designated to be served based on popularity of the resource.

8. A content delivery framework comprising:

a plurality of edge servers forming a first tier of servers; and

a plurality of parent servers forming a second tier of servers, said parent servers being distinct from said edge servers; and

at least one popularity service, implemented at least in part by hardware in combination with software, and constructed and adapted to obtain information from at least some of said edge servers about requests for content that has been specifically designated to be handled based on popularity of the content, and to provide said edge servers with information about which tier of servers should handle those requests for content, said popularity service making determinations based, at least in part, on a measure of popularity of requested content.

9. A method of content delivery in a content delivery network comprising a plurality of tiers of servers, including at least a first tier of servers and a second tier of servers, the method comprising:

(A) at a first server in one tier of said tiers of servers, obtaining a request from a client for a resource;

(B) if said resource is not available at said first server or at a peer of said first server, then selectively redirecting the request from the client to a second server in the network, said second server being in a tier distinct from said one tier containing said first server, said redirecting being based, at least in part, on (i) whether or not said resource is to be served based on popularity of the resource, and (ii) a current popularity value for said resource.

10. A method as in claim 9 wherein said first tier of servers comprises a plurality of edge servers and said second tier of servers comprises a plurality of parent servers, and wherein said first server is a parent server in said second tier and said second server is an edge server in said first tier.

11. A method as in claim 9 wherein said first tier of servers comprises a plurality of edge servers and said second tier of servers comprises a plurality of parent servers, and wherein said first server is an edge server in said first tier and said second server is a parent server in said second tier.

12. A method as in claim 9 wherein said first tier of servers comprises a plurality of edge servers and said second tier of servers comprises a plurality of parent servers, and wherein said plurality of tiers of servers further comprises an origin tier, and wherein said first server is a parent server in said second tier and said second server is a server in said origin tier.

24. The method of claim 9 wherein the current popularity value for the resource is based at least in part on a dynamic measure of popularity of the resource.

25. The method of claim 9 wherein the resource is part of an object, and wherein the current popularity value for the resource is based at least in part on whether the resource is an initial part of the object.

26. The method of claim 9 wherein the resource is part of an object, and wherein the current popularity value for the resource is based at least in part on whether the resource is for another part of the object, the initial part of the object having already been served to the client.

29. The method of claim 9 wherein whether or not said resource is to be served based on popularity of the resource is based at least in part on whether or not said resource is designated to be served based on popularity of the resource.