SYSTEM AND METHOD FOR DIGITAL MEDIA SERVER LOAD BALANCING

• US 20070124476A1
• Filed: 08/30/2006
• Published: 05/31/2007
• Est. Priority Date: 06/27/2003
• Status: Active Grant

• Current Assignee: Xylon LLC (Intellectual Ventures LLC)
• Original Assignee: Beach Unlimited LLC (Intellectual Ventures LLC)
• Inventors: Murphy, Craig, Oesterreicher, Richard
• Granted Patent: US 7,680,938 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• 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

Abstract

A system and method for load balancing a plurality of servers is disclosed. In a preferred embodiment, a plurality of servers in a video-on-demand or other multi-server system are divided into one or more load-balancing groups. Each server preferably maintains state information concerning other servers in its load-balancing group including information concerning content maintained and served by each server in the group. Changes in a server'"'"'s content status or other state information are preferably proactively delivered to other servers in the group. When a content request is received by any server in a load-balancing group, it evaluates the request in accordance with a specified algorithm to determine whether it should deliver the requested content itself or redirect the request to another server in its group. In a preferred embodiment, this determination is a function of information in the server'"'"'s state table.

Claims

1-20. -20. (canceled)

21. A method for servicing a request for content at a designated director server for a load balancing group, comprising:

receiving the request at the director server;

determining whether or not the content is present on the director server; and

responsively selecting a server to service the request such that;

the director selects itself to service the request when the requested content is present on the director; and

the director selects another server within the load balancing group to service the request when the requested content is not present on the director, said other server having stored thereon the content, the director selecting the other server using a state table comprising parametric information for servers in the load balancing group, wherein said parametric information comprises information identifying assets maintained on each server in the load balancing group.

22. The method of claim 21, further comprising designating the director in a round-robin fashion.

23. The method of claim 22, wherein the step of designating comprises designating the director on the basis of lowest load.

24. The method of claim 21, wherein said parametric information further comprises functional state and current load of each server.

25. The method of claim 21, wherein said parametric information further comprises whether each server comprises extended memory.

26. The method of claim 21, wherein said parametric information further comprises whether each server comprises an inline adaptable cache or whether each asset is a new release.

27. The method of claim 21, further comprising rejecting the request if the content is not present in the load balancing group.

28. The method of claim 21, further comprising forwarding the request to the selected other server.

29. The method of claim 21, further comprising redirecting the request to the selected other server.

30. The method of claim 21, wherein selecting the other server comprises:

calculating a load factor for the other servers in the load balancing group having the content;

identifying as available servers one or more of the other servers in the load balancing group whose parameters are below threshold limits;

selecting the other server from the available servers having the lowest load factor; and

otherwise selecting a server having the lowest load factor from the other servers in the load balancing group having the content.

31. A computer-readable medium comprising computer-executable instructions for performing the following steps:

receiving the request for content at a designated director server for a load balancing group;

determining whether or not the content is present on the director server; and

responsively selecting a server to service the request such that;

the director selects itself to service the request when the requested content is present on the director; and

the director selects another server within the load balancing group to service the request when the requested content is not present on the director, said other server having stored thereon the content, the director using a state table comprising parametric information for servers in the load balancing group, wherein said parametric information comprises information identifying assets maintained on each server in the load balancing group.

32. The computer-readable medium of claim 31, further comprising computer-executable instructions for designating the director in a round-robin fashion.

33. The computer-readable medium of claim 32, wherein the step of designating comprises designating the director on the basis of lowest load.

34. The computer-readable medium of claim 31, wherein said parametric information further comprises functional state and current load of each server.

35. The computer-readable medium of claim 31, wherein said parametric information further comprises whether each server comprises extended memory.

36. The computer-readable medium of claim 31, wherein said parametric information further comprises whether each server comprises an inline adaptable cache or whether each asset is a new release.

37. The computer-readable medium of claim 31, further comprising computer-executable instructions for rejecting the request if the content is not present in the load balancing group.

38. The computer-readable medium of claim 31, further comprising the forwarding the request to the selected other server.

39. The computer-readable medium of claim 31, further comprising the redirecting the request to the selected other server.

40. The computer-readable medium of claim 31, wherein selecting the other server comprises:

calculating a load factor for the other servers in the load balancing group having the content;

identifying as available servers one or more of the other servers in the load balancing group whose parameters are below threshold limits;

selecting the other server from the available servers having the lowest load factor; and

otherwise selecting a server having the lowest load factor from the other servers in the load balancing group having the content.