Domain name resolution based dynamic resource assignment

• US 20070118667A1
• Filed: 11/21/2005
• Published: 05/24/2007
• Est. Priority Date: 11/21/2005
• Status: Abandoned Application

• Current Assignee: Limelight Networks, Inc.
• Original Assignee: Limelight Networks, Inc.
• Inventors: Gordon, Michael, Stafford, Lee, Baldus, Gary, McCarthy, Nils, Harvell, Brad
• Application Number:
  US11/284,493
• Publication Number:
  US 20070118667A1
• Time in Patent Office: Days
• US Class Current: 709/238
• CPC Class Codes: H04L 45/74 Address processing for routing
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/4552 Lookup mechanisms between a plurality of directories; Synchronisation of directories, e.g. metadirectories
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• 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 67/1012 based on compliance of requirements or conditions with available server resources
• CPC Class Codes: H04L 67/1017 based on a round robin mechanism
• CPC Class Codes: H04L 67/1019 Random or heuristic server selection
• 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 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching

Abstract

A content delivery network (CDN) for delivering content over the Internet is disclosed in one embodiment. The CDN is configured to deliver content for others and includes a domain resolution service (DNS) server, caching servers and an Internet interface. The DNS server receives a first domain resolution request and produces a first DNS solution, and receives a second domain resolution request and produces a second DNS solution. The first and second domain resolution requests correspond to a same domain. The caching servers correspond to a plurality of addresses. The interface receives domain resolution requests, which include the first and second domain resolution requests, and transmits DNS solutions, which include the first and second DNS solutions. The first DNS solution comprises a first plurality of addresses corresponding to at least a first subset of the plurality of caching servers, and the second DNS solution comprises a second plurality of addresses corresponding to at least a second subset of the plurality of caching servers. The first DNS solution is different from the second DNS solution in that the second subset includes an address for a caching server not in the first subset.

Claims

1. A content delivery network (CDN) for delivering content over the Internet, wherein the CDN is configured to deliver content for others, the CDN comprising:

a domain resolution service (DNS) server, wherein;

the DNS server receives a first domain resolution request and produces a first DNS solution,

the DNS server receives a second domain resolution request and produces a second DNS solution, and

the first and second domain resolution requests correspond to a same domain;

a plurality of caching servers, wherein the plurality of caching servers correspond to a plurality of addresses;

an interface with the Internet, wherein;

the interface receives a plurality of domain resolution requests and transmits a plurality of DNS solutions,

the plurality of DNS solutions comprise the first and second DNS solutions,

the plurality of domain resolution requests comprise the first and second domain resolution requests,

the first DNS solution comprises a first plurality of addresses corresponding to at least a first subset of the plurality of caching servers,

the second DNS solution comprises a second plurality of addresses corresponding to at least a second subset of the plurality of caching servers, and

the first DNS solution is different from the second DNS solution in that the second subset includes an address for a caching server not in the first subset.

2. The CDN for delivering content over the Internet as recited in claim 1, wherein the first subset has fewer of the plurality of caching servers than are available in the plurality of DNS solutions for the domain.

3. The CDN for delivering content over the Internet as recited in claim 1, wherein additional servers are added to or removed from the plurality of caching servers in response to changes in a rate of content requests.

4. The CDN for delivering content over the Internet as recited in claim 1, wherein a size of the second subset is increased in response to changes in a rate of content requests.

5. The CDN for delivering content over the Internet as recited in claim 1, wherein the DNS server and the plurality of caching servers are at least part of a point of presence (POP).

6. The CDN for delivering content over the Internet as recited in claim 1, wherein failure of a health check on each of the plurality of caching servers causes removal of a failed caching server from the plurality of caching servers.

7. The CDN for delivering content over the Internet as recited in claim 1, wherein:

a determination is automatically made between the first and second DNS solutions to increase a quantity of addresses to provide in DNS solutions, and

the first plurality of addresses is greater in quantity than the second plurality of addresses.

8. The CDN for delivering content over the Internet as recited in claim 1, wherein:

the first and second DNS solutions list common addresses in the first and second subsets in a different order, and

the different order varies in at least one of a mixed-up fashion, a round-robin fashion or a random fashion.

9. The CDN for delivering content over the Internet as recited in claim 1, wherein the first and second subsets consist of a same number of caching servers from the plurality of caching servers.

10. The CDN for delivering content over the Internet as recited in claim 1, further comprising a wide area network coupling the plurality of caching servers together, wherein at least one of the plurality of caching servers is geographically remote from the others in the plurality of caching servers.

11. The CDN for delivering content over the Internet as recited in claim 1, wherein the CDN is a captive CDN integral to a content originator.

12. The CDN for delivering content over the Internet as recited in claim 1, wherein:

the DNS server, the plurality of caching servers, and the interface are at least part of a POP,

the POP is one of a plurality of POPs, and at least some of the plurality of POPs are geographically separated.

13. The CDN for delivering content over the Internet as recited in claim 1, wherein the first and second DNS solutions choose their servers from a same subset of the plurality of caching servers.

14. The CDN for delivering content over the Internet as recited in claim 1, wherein the DNS server and caching servers are geographically co-located.

15. A method for delivering content over the Internet, wherein the method comprises:

receiving a first domain resolution request with an Internet interface;

producing a first DNS solution corresponding to the first domain resolution request;

returning the first DNS solution with the Internet interface;

receiving a second domain resolution request with the Internet interface;

producing a second DNS solution corresponding to the second domain resolution request;

returning the second DNS solution with the Internet interface, wherein;

the first and second domain resolution requests correspond to a same domain or content originator,

a plurality of servers corresponding to a plurality of addresses,

the first DNS solution comprises a first plurality of addresses corresponding to at least a first subset of the plurality of servers,

the second DNS solution comprises a second plurality of addresses corresponding to at least a second subset of the plurality of servers, and

the first plurality of addresses includes at least one address that is different from the second plurality of addresses.

16. The method for delivering content over the Internet as recited in claim 15, further comprising a step of determining that at least one of the first plurality of addresses should be removed from further DNS solutions, wherein the second DNS solution does not include the one.

17. The method for delivering content over the Internet as recited in claim 15, further comprising steps of:

determining that at least one server in the first subset is receiving content requests at a rate beyond a threshold;

excluding the at least one server from the second DNS solution; and

substituting another server to replace the at least one server.

18. The method for delivering content over the Internet as recited in claim 15, further comprising steps of:

determining that at least one server in the plurality of servers is active beyond a threshold; and

substituting the at least one server for another server.

19. The method for delivering content over the Internet as recited in claim 15, further comprising steps of:

determining that at least one server in the first subset fails a health check; and

excluding the at least one server from the second DNS solution.

20. The method for delivering content over the Internet as recited in claim 15, further comprising steps of:

determining that at least one server in the first subset fails a health check; and

substituting the at least one server for another server.

21. The method for delivering content over the Internet as recited in claim 15, further comprising steps of:

determining that at least one of the first plurality of addresses is over utilized, and

removing the one from future DNS solutions.

22. The method for delivering content over the Internet as recited in claim 15, wherein the first subset is chosen from a larger number of servers that could be selected for DNS solutions.

23. The method for delivering content over the Internet as recited in claim 15, wherein the first subset is smaller than the second subset.

24. The method for delivering content over the Internet as recited in claim 15, further comprising steps of:

determining that activity of one or more of the first subset exceeds a predetermined threshold;

increasing an allocation from the plurality of servers in the second subset, whereby the second subset is larger than the first subset.

25. The method for delivering content over the Internet as recited in claim 15, further comprising steps of:

determining that at least one of the plurality of servers is active beyond a threshold; and

excluding the at least one from future DNS solutions.

26. The method for delivering content over the Internet as recited in claim 15, wherein the Internet interface and the plurality of servers are geographically collocated.

27. A machine-readable medium having machine-executable instructions for performing the machine-implementable method for delivering content over the Internet of claim 15.

28. A system adapted to perform the machine-implementable method for delivering content over the Internet of claim 15.

29. A method for delivering content over a network, wherein the method comprises:

receiving a first domain resolution request with a network interface;

determining a set of a plurality of servers allocated to a domain;

producing a first DNS solution corresponding to the first domain resolution request;

returning the first DNS solution with the network interface;

receiving a second domain resolution request with the network interface;

producing a second DNS solution corresponding to the second domain resolution request;

returning the second DNS solution with the network interface, wherein;

the first and second domain resolution requests indicate the domain,

the plurality of servers corresponding to a plurality of addresses,

the first DNS solution comprises a first plurality of addresses corresponding to at least a first subset of the set,

the second DNS solution comprises a second plurality of addresses corresponding to at least a second subset of the set, and

the first DNS solution includes an address absent from the second DNS solution.

30. The method for delivering content over the network as recited in claim 29, wherein the network interface and the plurality of servers are geographically collocated.

31. The method for delivering content over the network as recited in claim 29, further comprising steps of:

determining that at least one address in the first subset is active at a rate beyond a threshold;

excluding the at least one address from the second DNS solution; and

substituting another address to replace the at least one address.

32. The method for delivering content over the network as recited in claim 29, further comprising steps of:

determining that at least one server in the plurality of servers is active beyond a threshold; and

substituting the at least one server for another server.

33. The method for delivering content over the network as recited in claim 29, further comprising steps of:

determining that at least one server in the plurality of servers fails a health check; and

removing the at least one server from the plurality of servers.

34. The method for delivering content over the network as recited in claim 29, further comprising steps of:

determining that at least one server in the plurality of servers fails a health check; and

substituting the at least one server for another server.

35. The method for delivering content over the network as recited in claim 29, further comprising steps of:

determining at least one of the plurality of servers in the set is active beyond a threshold; and

removing the one from the set based upon the immediately-preceding determining step.

36. The method for delivering content over the network as recited in claim 29, wherein at least one of the first and second DNS solutions includes a time to live.

37. A machine-readable medium having machine-executable instructions for performing the machine-implementable method for delivering content over the network of claim 29.

38. A system for delivering content over the Internet, the system comprising:

a domain resolution service (DNS) server, wherein;

the DNS server receives a first domain resolution request and produces a first DNS solution,

the DNS server receives a second domain resolution request and produces a second DNS solution, and

the first and second domain resolution requests correspond to a same domain;

a plurality of servers, wherein the plurality of servers correspond to a plurality of addresses;

an interface with the Internet, wherein;

the interface receives a plurality of domain resolution requests and transmits a plurality of DNS solutions,

the plurality of DNS solutions comprise the first and second DNS solutions,

the plurality of domain resolution requests comprise the first and second domain resolution requests,

the first DNS solution comprises a first plurality of addresses corresponding to at least a first subset of the plurality of servers,

the second DNS solution comprises a second plurality of addresses corresponding to at least a second subset of the plurality of servers, and

the second DNS solution includes an address absent from the second DNS solution.

39. The system for delivering content over the Internet as recited in claim 38, wherein the first subset has fewer of the plurality of servers than are available in the plurality of DNS solutions for the domain.

40. The system for delivering content over the Internet as recited in claim 38, wherein additional servers are added to or removed from the plurality of servers in response to changes in a rate of content requests.

41. The system for delivering content over the Internet as recited in claim 38, wherein a size of the second subset is decreased in response to changes in a rate of content requests.

42. The system for delivering content over the Internet as recited in claim 38, wherein the DNS server and the plurality of servers are geographically collocated in a POP.

43. The system for delivering content over the Internet as recited in claim 38, wherein failure of a health check on each of the plurality of servers causes removal of a failed caching server from the plurality of caching servers.