System and method for highly-scalable real-time and time-based data delivery using server clusters

• US 20040088412A1
• Filed: 07/24/2002
• Published: 05/06/2004
• Est. Priority Date: 07/24/2002
• Status: Active Grant

• Current Assignee: Espial Incorporated (Enghouse Systems Limited)
• Original Assignee: Espial Incorporated (Enghouse Systems Limited)
• Inventors: Wang, James, Muthukumarasamy, Jayakumar, Menon, Satish N., Horen, Robert, Thota, Laxmi, John, Ranjit
• Granted Patent: US 7,403,993 B2
• Time in Patent Office: Days
• US Class Current: 709/226
• CPC Class Codes: G06F 16/40 of multimedia data, e.g. slideshows comprising image and additional audio data retrieval of still image data G06F16/50; retrieval of audio data G06F16/60; retrieval of video data G06F16/70
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

The present invention provides loosely-coupled cluster systems comprising a plurality of servers based on storage attached to the plurality of servers. Videos, or other assets, are automatically replicated within the server system to increase the number of concurrent play requests serviceable. The server systems can detect spikes in demand that may exceed the guaranteed number of concurrent play requests serviceable and dynamically transfer the high-in-demand or ‘hot’ asset to servers in the cluster that do not have the video. Alternatively, instead of transferring the entire asset, varying length prefixes of the asset may be transferred depending on the availability of resources. The remainder of the asset is transferred in some embodiments on demand with sufficient buffering or other storage to guarantee playback to the user or subscriber according to the required quality of service (QOS).

Claims

1. A server system for time-based media streaming comprising:

a plurality of servers coupled for communication with each other, including a first server and second server, said first server comprising;

a first computer-readable storage medium encoded with stored server information comprising asset information associated with said second server;

a first computer-readable storage device associated with said first server encoded with first asset information; and

a second computer-readable storage device associated with said second server encoded with second asset information.

2. A server system according to claim 1, wherein said first computer-readable storage medium is further encoded with load information corresponding to said second server.

3. A server system according to claim 1, wherein said first asset information comprises a first asset.

4. A server system according to claim 3, wherein said first asset comprises a video.

5. A server system according to claim 1, wherein said first asset information comprises a fraction of a first asset.

6. A server system according to claim 5, wherein said fraction of said first asset comprises a prefix of said first asset.

7. A server system according to claim 1, wherein said first asset information comprises metadata associated with a first asset.

8. A server system according to claim 1, wherein said load information associated with said second server comprises an overall load factor.

9. A server system according to claim 1, wherein said overall load factor is based on information about said second server chosen from the group consisting of:

percent CPU used, memory used, network bandwidth available, and combinations thereof.

10. A server system according to claim 1, further comprising a load balancer in communication with said plurality of servers.

11. A server system according to claim 1, further comprising a shared storage system accessible to each of said plurality of servers.

12. A server system according to claim 11, wherein said shared storage system comprises network attached storage.

13. A server system according to claim 11, wherein said shared storage system comprises a storage area network.

14. A server system according to claim 11, wherein said first asset information comprises metadata.

15. A server system according to claim 14, wherein said shared storage system stores a plurality of media assets and said first computer readable storage device and said second computer readable storage device stores metadata associated with at least one of said plurality of media assets.

16. A server system according to claim 1, further comprising a centrally administered server cluster accessible to each of said plurality of servers.

17. A server system according to claim 16, wherein said centrally administered server cluster stores a plurality of assets.

18. A server system according to claim 17, wherein said first computer readable storage device and said second computer readable storage device store metadata associated with an asset and a prefix associated with said asset.

50. A server system according to claim 4, wherein said video comprises a movie video in MPEG-2 format for payback at 30 frames/second.

51. A server system according to claim 50, wherein said movie video has a length of between substantially ½

hour and 4 hours.

52. A server system according to claim 51, wherein said movie video has a length of between substantially 1 hour and 2 hours.

53. A server system according to claim 1, wherein said time-based media streaming comprises real-time media streaming.

19. A method for time-based streaming of assets, said method comprising:

receiving a request for an asset at a first server;

determining if said first server has said asset;

determining if said first server has sufficient resources to stream said asset;

streaming said asset while maintaining a time-base for said streamed asset if said first server has said asset and said first server has sufficient resources to stream said asset;

if said first server does not have said asset, or said first server does not have sufficient resources to stream said asset, attempting to identify a second server having said asset and sufficient resources to stream said asset; and

forwarding said request to said identified second server.

20. A method for time-based streaming of assets and load-balancing, said method comprising:

receiving a request for an asset at a first server having said asset and sufficient resources to stream said asset;

streaming said asset while maintaining a time-base for said streamed asset if said first server has a first server load level less than a load threshold value; and

if said first server has a load level greater than a load threshold level, said method further comprising;

attempting to find a second server having said asset, sufficient resources to stream said asset, and a second server load level less than said first server load level;

forwarding said request if said second server is located; and

streaming said asset while maintaining a time-base for said streamed asset if said second server is not located.

21. A method according to claim 20, wherein said load threshold level is predetermined and adjustable.

22. A method according to claim 20, wherein said load threshold level is a number between 0 and 100.

23. A method for time-based streaming of assets, said method comprising:

receiving a request for an asset at a first server;

determining if said first server has said asset;

determining if said first server has sufficient resources to stream said asset;

if said first server does not have said asset or said first server does not have sufficient resources to stream said asset, forwarding said request to a second server having said asset and sufficient resources to stream said asset;

if said first server has said asset and sufficient resources to stream said asset, determining if said first server has a load level less than a load threshold value;

if said first server has a first server load level less than a load threshold value, streaming said asset and maintaining a time-base for said streamed asset; and

if said first server has a load level greater than a load threshold level,

attempting to find a second server having said asset, sufficient resources to stream said asset, and a second server load level less than said first server load level;

forwarding said request if said second server is located; and

streaming said asset and maintaining a time-base for said streamed asset if said second server is not located.

24. A method according to claim 23, wherein said load threshold level is predetermined and adjustable.

25. A method according to claim 24, wherein said load threshold level is a number between 0 and 100.

26. A method according to claim 23, further comprising:

determining if said asset is hot; and

copying information associated with said asset to a second server if said asset is hot.

27. A method according to claim 26, wherein said determining if said asset is hot comprises determining if a number of requests for said asset during a predetermined hot asset period exceeds a predetermined hot asset count.

28. A method according to claim 26, wherein said determining if said asset is hot comprises determining if a number of requests for said asset during a predetermined hot asset period equals or exceeds a predetermined hot asset count.

29. A method according to claim 26, wherein said copying information comprises copying said asset to said second server.

30. A method according to claim 26, wherein said copying information comprises copying metadata associated with said asset to said second server.

31. A method according to claim 26, wherein said copying information comprises copying a prefix of said asset of said second server.

32. A method according to claim 23, wherein said determining if said asset exists at said first server comprises determining if information about said asset is stored in a first computer readable storage medium associated with said first server.

33. A method according to claim 23, wherein said information about said asset comprises information selected from the group consisting of said asset, metadata associated with said asset, a prefix of said asset, and combinations thereof.

34. A method according to claim 23, wherein a prefix of said asset exists at said first server, said method further comprising:

requesting said asset from a server having access to said asset.

35. A method according to claim 23, wherein a prefix of said asset exists at said first server, said method further comprising:

requesting said asset from a centralized storage system.

36. A method according to claim 23, further comprising:

transmitting load information to other servers in said cluster.

37. A method according to claim 36, wherein said transmitting load information comprises computing a load factor and transmitting said load metric to other servers in said cluster.

38. A method according to claim 37, wherein said load factor comprises a measure of resources at said first server, said resources chosen from the group consisting of CPU idle time, amount of free physical memory, amount of free physical swamp memory, and available network bandwidth.

39. A computer program product for use in conjunction with a first server having at least one processor and a memory coupled to the processor, the first server being in communication with at least one second server, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism, comprising:

a program module that directs the first server to function in a specified manner to provide load-balancing functionality upon receiving a request for an asset, the program module including instructions for;

determining if said first server has said asset;

determining if said first server has sufficient resources to stream said asset;

streaming said asset while maintaining a time-base for said streamed asset if said first server has said asset and said first server has sufficient resources to stream said asset;

if said first server does not have said asset, or said first server does not have sufficient resources to stream said asset, attempting to identify a second server having said asset and sufficient resources to stream said asset; and

forwarding said request to said identified second server.

40. A computer program product for use in conjunction with a first server having at least one processor and a memory coupled to the processor, the first server being in communication with at least one second server, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism, comprising:

a program module that directs the first server to function in a specified manner to provide load-balancing functionality upon receiving a request for an asset wherein said first server has said asset and sufficient resources to stream said asset, the program module including instructions for;

streaming said asset if said first server has a first server load level less than a load threshold value; and

if said first server has a load level greater than a load threshold level, said method further comprising;

attempting to find a second server having said asset, sufficient resources to stream said asset, and a second server load level less than said first server load level;

forwarding said request if said second server is located; and

streaming said request if said second server is not located.

41. The computer program product of claim 40, wherein said program module further includes instructions for:

storing a load threshold value; and

updating said load threshold value upon receiving an updated load threshold value.

42. A computer program product for use in conjunction with a first server having at least one processor and a memory coupled to the processor, the first server being in communication with at least one second server, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism, comprising:

a program module that directs the first server to function in a specified manner to provide load-balancing functionality upon receiving a request for an asset, the program module including instructions for;

determining if said first server has said asset;

determining if said first server has sufficient resources to stream said asset;

if said first server does not have said asset or said first server does not have sufficient resources to stream said asset, forwarding said request to a second server having said asset and sufficient resources to stream said asset;

if said first server has said asset and sufficient resources to stream said asset, determining if said first server has a load level less than a load threshold value;

if said first server has a first server load level less than a load threshold value, streaming said asset; and

if said first server has a load level greater than a load threshold level,

attempting to find a second server having said asset, sufficient resources to stream said asset, and a second server load level less than said first server load level;

forwarding said request if said second server is located; and

streaming said request if said second server is not located.

43. The computer program product of claim 42, wherein said program module further includes instructions for:

updating said load threshold value upon receiving an updated load threshold value.

44. A server system for time-based media streaming comprising:

a plurality of servers coupled for communication with each other, including a first server and second server, said first server comprising

a first computer-readable storage medium encoded with server information comprising asset information associated with said second server; and

a computer program mechanism, the computer program mechanism, comprising;

a program module that directs the first server to function in a specified manner to provide load-balancing functionality upon receiving a request for an asset, the program module including instructions for;

determining if said first server has said asset;

determining if said first server has sufficient resources to stream said asset;

streaming said asset if said first server has said asset and said first server has sufficient resources to stream said asset;

if said first server does not have said asset, or said first server does not have sufficient resources to stream said asset, attempting to identify a second server having said asset and sufficient resources to stream said asset; and

forwarding said request to said identified second server;

a first computer-readable storage device associated with said first server encoded with first asset information; and

a second computer-readable storage device associated with said second server encoded with second asset information.

45. A server system for time-based media streaming comprising:

a plurality of servers coupled for communication with each other, including a first server and second server, said first server comprising

a first computer-readable storage medium encoded with server information comprising asset information associated with said second server; and

a computer program mechanism, the computer program mechanism, comprising;

a program module that directs the first server to function in a specified manner to provide load-balancing functionality upon receiving a request for an asset wherein said first server has said asset and sufficient resources to stream said asset, the program module including instructions for;

streaming said asset if said first server has a first server load level less than a load threshold value; and

if said first server has a load level greater than a load threshold level, said method further comprising;

attempting to find a second server having said asset, sufficient resources to stream said asset, and a second server load level less than said first server load level;

forwarding said request if said second server is located; and

streaming said request if said second server is not located;

a first computer-readable storage device associated with said first server encoded with first asset information; and

a second computer-readable storage device associated with said second server encoded with second asset information.

46. A server system for time-based media streaming comprising:

a plurality of servers coupled for communication with each other, including a first server and second server, said first server comprising

a first computer-readable storage medium encoded with server information comprising asset information associated with said second server; and

a computer program mechanism, the computer program mechanism, comprising;

a program module that directs the first server to function in a specified manner to provide load-balancing functionality upon receiving a request for an asset, the program module including instructions for;

determining if said first server has said asset;

determining if said first server has sufficient resources to stream said asset;

if said first server does not have said asset or said first server does not have sufficient resources to stream said asset, forwarding said request to a second server having said asset and sufficient resources to stream said asset;

if said first server has said asset and sufficient resources to stream said asset, determining if said first server has a load level less than a load threshold value;

if said first server has a first server load level less than a load threshold value, streaming said asset; and

if said first server has a load level greater than a load threshold level, attempting to find a second server having said asset,

 

sufficient resources to stream said asset, and a second server load level less than said first server load level;

 

forwarding said request if said second server is located; and

 

streaming said request if said second server is not located;

a first computer-readable storage device associated with said first server encoded with first asset information; and

a second computer-readable storage device associated with said second server encoded with second asset information.

47. The server system for time-based media streaming in claim 46, wherein said time-based media streaming comprises maintaining streaming of said media within a predetermined play rate range.

48. The server system for time-based media streaming in claim 46, wherein said time-based media streaming comprises maintaining streaming of said media within a predetermined play rate range, and maintaining said media play within a predetermined delay relative to an absolute time reference.

49. The server system for time-based media streaming in claim 46, wherein said time-based media streaming comprises real-time media streaming.

54. A business model for operating a time-base accurate asset streaming business, said business model comprising:

operating a first server to receive and service requests for an asset, said first server (i) receiving a request for an asset, (ii) determining if said first server has said asset available for time-base accurately streaming and has sufficient resources to time-base accurately stream said asset, and (iii) time-base accurately streaming said asset if it is determined that said first server has said asset available for time-base accurately streaming and has sufficient resources to time-base accurately stream said asset; and

if said determining indicates that said first server does not have said asset available for time-base accurately streaming or does not have sufficient resources to time-base accurately stream said asset, then;

(i) identifying a second server having said asset available for time-base accurately streaming and sufficient resources to time-base accurately stream said asset , and (ii) forwarding said request to said identified second server for servicing by said second server.

55. The business model for operating a time-base accurate asset streaming business as in claim 54, wherein said asset comprises a multi-media asset including a video.

56. The business model for operating a time-base accurate asset streaming business as in claim 54, wherein said determining if said first server has sufficient resources to stream said asset in real-time includes performing first server load assessment.

57. The business model for operating a time-base accurate asset streaming business as in claim 54, further comprising operating a dynamically determinable plurality of servers or server clusters where the number of servers or server clusters is any number greater than or equal to two.

58. The business model for operating a time-base accurate asset streaming business as in claim 57, wherein the number of servers or server clusters comprises any number between 2 and 1000.