Arrangement in a server for providing dynamic domain name system services for each received request

• US 7,499,998 B2
• Filed: 12/01/2004
• Issued: 03/03/2009
• Est. Priority Date: 12/01/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Toebes, John, Walker, Douglas Jay, Turner, Bryan C.
• Primary Examiner(s): Hu; Jinsong
• Application Number:
  US11/000,041
• Publication Number:
  US 20060129665A1
• Time in Patent Office: 1,553 Days
• Field of Search: 709/203, 709/204, 709/219, 709/225, 709/226, 709/245, 718/105
• US Class Current: 709/225
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• 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 67/101 based on network conditions
• CPC Class Codes: H04L 67/1014 based on the content of a request
• 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 67/1021 based on client or server locations
• CPC Class Codes: H04L 67/303 Terminal profiles
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements

Abstract

A Domain Name System (DNS) server is configured for dynamically selecting, for a client device, a selected resolution from available resolutions, the selected resolution identifying at least one destination for the specified service. The dynamic selection of the selected resolution is based on an attribute of the client device and/or a determined attribute of the network. Hence, the selected resolution directs the client device to a specific server based on prescribed selection criteria, for example service level agreements, the location of the client device, network performance or detected congestion conditions, authentication of the user of the client device, etc. The selected resolution also can be for enforcement of load balancing policies.

Claims

1. A method in a Domain Name System (DNS) server in a network, the method comprising:

receiving, by the DNS server and via the network, a request from a client device for identification of at least one destination that provides in the network a specified service;

dynamically selecting by the DNS server, for the client device, a selected resolution from a plurality of available resolutions, the selected resolution identifying at least one destination for the specified service, the dynamic selection of the selected resolution based on the DNS server determining, based on an attribute of the client device and a determined attribute of the network, whether the client device has an established service relationship authorizing the client device to access a restricted level of the specified service; and

outputting by the DNS server onto the network the selected resolution for delivery to the client device.

2. The method of claim 1, wherein the attribute of the client device includes a location of the client device within the network, the dynamically selecting including selecting the selected resolution based on the location of the client device within the network.

3. The method of claim 2, wherein the determined attribute of the network includes an identified distance between the at least one destination and the client device, the selected resolution being selected based on the identified distance relative to other distances of the respective available resolutions.

4. The method of claim 2, wherein:

the attribute of the client device further includes a service level associated with a user of the client device as the established service relationship;

the dynamically selecting including selecting the selected resolution based on the location of the client device within the network and based on the service level of the user as the established service relationship.

5. The method of claim 4, wherein the attribute of the network further includes a corresponding capacity for the at least one destination, the selected resolution being selected based on the capacity of the corresponding at least one destination as the restricted level of the specified service and based on the service level being identified as authorized to obtain the specified service at the restricted level according to said capacity.

6. The method of claim 2, wherein the determined attribute of the network includes the specified service being identified as distributed among a plurality of servers in the network, the dynamically selecting including:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

7. The method of claim 1, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the dynamically selecting including:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

8. The method of claim 1, wherein the determined attribute of the network includes identifying congestion conditions at the respective destinations, the selecting of the selected resolution based on the identified congestion conditions.

9. The method of claim 1, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the dynamically selecting including selecting the selected resolution, that identifies a corresponding one of the servers, according to a prescribed load balancing sequence.

10. The method of claim 9, further comprising:

receiving a second request from the client device, subsequent to said request from the client device, for at least one destination that provides said specified service; and

dynamically selecting, in response to the second request, said selected resolution based on said selected resolution having been selected in response to the request.

11. The method of claim 1, wherein:

the attribute of the client device includes whether the client device has a prescribed authentication as the established service relationship;

the attribute of the network includes a public destination for any client device lacking the prescribed authentication and a private destination as the restricted level of the specified service for any client device having the prescribed authentication;

the dynamically selecting including selecting the selected destination, for identification of a corresponding one of the public destination or the private destination, based on whether the client device has the prescribed authentication.

12. A Domain Name System (DNS) server in a network, the server comprising:

an IP interface configured for receiving via the network a request from a client device for identification of at least one destination that provides in the network a specified service; and

a resolution resource configured for dynamically selecting, for the client device, a selected resolution from a plurality of available resolutions, the selected resolution identifying at least one destination for the specified service, the dynamic selection of the selected resolution based on the resolution resource determining, based on an attribute of the client device and a determined attribute of the network, whether the client device has an established service relationship authorizing the client device to access a restricted level of the specified service;

the IP interface configured for outputting onto the network the selected resolution for delivery to the client device.

13. The server of claim 12, wherein the attribute of the client device includes a location of the client device within the network, the resolution resource configured for selecting the selected resolution based on the location of the client device within the network.

14. The server of claim 13, wherein the determined attribute of the network includes an identified distance between the at least one destination and the client device, the resolution resource configured for selecting the selected resolution based on the identified distance relative to other distances of the respective available resolutions.

15. The server of claim 13, wherein:

the attribute of the client device further includes a service level associated with a user of the client device as the established service relationship;

the resolution resource configured for selecting the selected resolution based on the location of the client device within the network and based on the service level of the user as the established service relationship.

16. The server of claim 15, wherein the attribute of the network further includes a corresponding capacity for the at least one destination, the resolution resource configured for selecting the selected resolution based on the capacity of the corresponding at least one destination as the restricted level of the specified service and based on the service level being identified as authorized to obtain the specified service at the restricted level according to said capacity.

17. The server of claim 13, wherein the determined attribute of the network includes the specified service being identified as distributed among a plurality of servers in the network, the resolution resource configured for:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

18. The server of claim 12, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the resolution resource configured for:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

19. The server of claim 12, wherein the determined attribute of the network includes identifying congestion conditions at the respective destinations, the resolution resource configured for selecting the selected resolution based on the identified congestion conditions.

20. The server of claim 12, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the resolution resource configured for selecting the selected resolution, that identifies a corresponding one of the servers, according to a prescribed load balancing sequence.

21. The server of claim 20, wherein:

the IP interface is configured for receiving a second request from the client device, subsequent to said request from the client device, for at least one destination that provides said specified service; and

the resolution resource is configured for dynamically selecting, in response to the second request, said selected resolution based on said selected resolution having been selected in response to the request.

22. The server of claim 12, wherein:

the attribute of the client device includes whether the client device has a prescribed authentication as the established service relationship;

the attribute of the network includes a public destination for any client device lacking the prescribed authentication and a private destination as the restricted level of the specified service for any client device having the prescribed authentication;

the resolution resource configured for selecting the selected destination, for identification of a corresponding one of the public destination or the private destination, based on whether the client device has the prescribed authentication.

23. A computer readable storage medium having stored thereon sequences of executable instructions for a Domain Name System (DNS) server in a network to output a resolution to a client device in response to a request, the sequences of executable instructions including instructions for:

receiving, by the DNS server and via the network, a request from a client device for identification of at least one destination that provides in the network a specified service;

dynamically selecting by the DNS server, for the client device, a selected resolution from a plurality of available resolutions, the selected resolution identifying at least one destination for the specified service, the dynamic selection of the selected resolution based on the DNS server determining, based on an attribute of the client device and a determined attribute of the network, whether the client device has an established service relationship authorizing the client device to access a restricted level of the specified service; and

outputting by the DNS server onto the network the selected resolution for delivery to the client device.

24. The medium of claim 23, wherein the attribute of the client device includes a location of the client device within the network, the dynamically selecting including selecting the selected resolution based on the location of the client device within the network.

25. The medium of claim 24, wherein the determined attribute of the network includes an identified distance between the at least one destination and the client device, the selected resolution being selected based on the identified distance relative to other distances of the respective available resolutions.

26. The medium of claim 24, wherein:

the attribute of the client device further includes a service level associated with a user of the client device as the established service relationship;

the dynamically selecting including selecting the selected resolution based on the location of the client device within the network and based on the service level of the user as the established service relationship.

27. The medium of claim 26, wherein the attribute of the network further includes a corresponding capacity for the at least one destination, the selected resolution being selected based on the capacity of the corresponding at least one destination as the restricted level of the specified service and based on the service level being identified as authorized to obtain the specified service at the restricted level according to said capacity.

28. The medium of claim 24, wherein the determined attribute of the network includes the specified service being identified as distributed among a plurality of servers in the network, the dynamically selecting including:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

29. The medium of claim 23, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the dynamically selecting including:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

30. The medium of claim 23, wherein the determined attribute of the network includes identifying congestion conditions at the respective destinations, the selecting of the selected resolution based on the identified congestion conditions.

31. The medium of claim 23, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the dynamically selecting including selecting the selected resolution, that identifies a corresponding one of the servers, according to a prescribed load balancing sequence.

32. The medium of claim 31, further comprising instructions for:

receiving a second request from the client device, subsequent to said request from the client device, for at least one destination that provides said specified service; and

dynamically selecting, in response to the second request, said selected resolution based on said selected resolution having been selected in response to the request.

33. The medium of claim 23, wherein:

the attribute of the client device includes whether the client device has a prescribed authentication as the established service relationship;

the attribute of the network includes a public destination for any client device lacking the prescribed authentication and a private destination as the restricted level of the specified service for any client device having the prescribed authentication;

the dynamically selecting including selecting the selected destination, for identification of a corresponding one of the public destination or the private destination, based on whether the client device has the prescribed authentication.

34. A Domain Name System (DNS) server in a network, the server comprising:

an IP interface configured for receiving via the network a request from a client device for at least one destination that provides in the network a specified service; and

dynamically selecting, for the client device, a selected resolution from a plurality of available resolutions, the selected resolution identifying at least one destination for the specified service, the dynamic selection of the selected resolution based on the dynamically selecting determining, based on an attribute of the client device and a determined attribute of the network, whether the client device has an established service relationship authorizing the client device to access a restricted level of the specified service;

the IP interface configured for outputting onto the network the selected resolution for delivery to the client device.

35. The server of claim 34, wherein the attribute of the client device includes a location of the client device within the network, the dynamically selecting configured for selecting the selected resolution based on the location of the client device within the network.

36. The server of claim 35, wherein the determined attribute of the network includes an identified distance between the at least one destination and the client device, the dynamically selecting configured for selecting the selected resolution based on the identified distance relative to other distances of the respective available resolutions.

37. The server of claim 35, wherein:

the attribute of the client device further includes a service level associated with a user of the client device as the established service relationship;

the dynamically selecting configured for selecting the selected resolution based on the location of the client device within the network and based on the service level of the user as the established service relationship.

38. The server of claim 37, wherein the attribute of the network further includes a corresponding capacity for the at least one destination, the dynamically selecting configured for selecting the selected resolution based on the capacity of the corresponding at least one destination as the restricted level of the specified service and based on the service level being identified as authorized to obtain the specified service at the restricted level according to said capacity.

39. The server of claim 35, wherein the determined attribute of the network includes the specified service being identified as distributed among a plurality of servers in the network, the dynamically selecting configured for:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

40. The server of claim 34, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the dynamically selecting configured for:

identifying the one server closest to the client device; and

selecting the selected resolution based on the corresponding at least one destination identifying the one server.

41. The server of claim 34, wherein the determined attribute of the network includes identifying congestion conditions at the respective destinations, the dynamically selecting configured for selecting the selected resolution based on the identified congestion conditions.

42. The server of claim 34, wherein the determined attribute of the network includes identifying the specified service as being distributed among a plurality of servers in the network, the dynamically selecting configured for selecting the selected resolution, that identifies a corresponding one of the servers, according to a prescribed load balancing sequence.

43. The server of claim 42, wherein:

the IP interface is configured for receiving a second request from the client device, subsequent to said request from the client device, for at least one destination that provides said specified service; and

the dynamically selecting is configured for dynamically selecting, in response to the second request, said selected resolution based on said selected resolution having been selected in response to the request.

44. The server of claim 34, wherein:

the attribute of the client device includes whether the client device has a prescribed authentication as the established service relationship;

the attribute of the network includes a public destination for any client device lacking the prescribed authentication and a private destination as the restricted level of the specified service for any client device having the prescribed authentication;

the dynamically selecting configured for selecting the selected destination, for identification of a corresponding one of the public destination or the private destination, based on whether the client device has the prescribed authentication.