Caching media data using content sensitive object identifiers

• US 20050165828A1
• Filed: 10/14/2004
• Published: 07/28/2005
• Est. Priority Date: 06/12/2001
• Status: Active Grant

• Current Assignee: Network Appliance Incorporated (NetApp, Inc.)
• Original Assignee: Network Appliance Incorporated (NetApp, Inc.)
• Inventors: Lango, Jason, Roussos, Konstantinos, Wagner, J. Christopher, Merrick, Jeffrey, Tsai, Robert
• Granted Patent: US 7,376,790 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 12/0866 for peripheral storage systems, e.g. disk cache
• CPC Class Codes: G06F 2212/264 Remote server
• CPC Class Codes: G06F 2212/463 File
• CPC Class Codes: G06F 2212/464 Multimedia object, e.g. image, video
• CPC Class Codes: H04L 67/561 Adding application-functional data or data for application control, e.g. adding metadata
• CPC Class Codes: H04L 67/5682 Policies or rules for updating, deleting or replacing the stored data
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure

Abstract

Techniques for caching media data, including streaming media data, using content-sensitive identifiers. The content-sensitive identifiers enable a caching proxy or a caching server to unambiguously determine the version or contents of media data cached by the caching proxy for a particular data pointer or data reference (e.g., a URL) such that an appropriate version of the media data can be served to a requesting client system in an efficient and economical manner.

Claims

1-20. -20. (canceled)

21. A method comprising:

receiving information corresponding to a data pointer for use in locating a data set;

creating an object to store at least a portion of the data set; and

generating an object identifier for the object to unambiguously identify the data stored in the object relative to any other data associated with the data pointer.

22. A method as recited in claim 21, wherein the data pointer comprises a Uniform Resource Locator (URL).

23. A method as recited in claim 21, further comprising:

creating a plurality of objects to store the data set, including said object, such that each of the objects stores a portion of the data set; and

generating an object identifier for each of the objects, including said object, to unambiguously identify the data stored in each object relative to any other data associated with the data pointer.

24. A method as recited in claim 23, wherein the information corresponding to the data pointer includes meta-data indicating characteristics of the data set.

25. A method as recited in claim 24, wherein the data set comprises streaming media data.

26. A method as recited in claim 24, wherein generating the object identifier for each of the objects comprises generating the object identifier for each object based upon the portion of the data set which is stored by the object and based on at least a portion of the meta-data.

27. A method as recited in claim 26, wherein said portion of the meta-data comprises version information relating to the data set.

28. A method as recited in claim 27, wherein generating the object identifier for each of the objects further comprises generating the object identifier for each object based on the data pointer.

29. A method as recited in claim 24, wherein generating the object identifier for each of the objects further comprises concatenating a plurality of strings to form the object identifier of each object.

30. A method as recited in claim 29, wherein a first one of the strings is the data pointer.

31. A method as recited in claim 30, wherein a second one of the strings represents at least a portion of the meta-data.

32. A method as recited in claim 31, wherein the second one of the strings represents version information in the meta-data.

33. A method as recited in claim 31, wherein a third one of the strings indicates the position within the set of data of the portion of data stored in the object.

34. A method as recited in claim 33, wherein a fourth one of the strings indicates an encoding of the data stored in the object.

35. A processing system comprising:

a processor; and

a network interface coupled to the processor, through which to communicate over a network; and

a memory coupled to the processor and storing instructions which, when executed by the processor, cause the processing system to perform a process that includes

receiving information corresponding to a data pointer for use in locating a data set;

creating a plurality of objects to store the data set, such that each of the objects stores a portion of the data set; and

generating an object identifier for each of the objects to unambiguously identify the data stored in each object relative to any other data associated with the data pointer.

36. A processing system as recited in claim 35, wherein the data pointer comprises a Uniform Resource Locator (URL).

37. A processing system as recited in claim 35, wherein the information corresponding to the data pointer includes meta-data indicating characteristics of the data set.

38. A processing system as recited in claim 37, wherein the data set comprises streaming media data.

39. A processing system as recited in claim 38, wherein generating the object identifier for each of the objects comprises generating the object identifier for each object based upon the portion of the data set which is stored by the object and based on at least a portion of the meta-data.

40. A processing system as recited in claim 39, wherein said portion of the meta-data comprises version information relating to the data set.

41. A processing system as recited in claim 35, wherein generating the object identifier for each of the objects further comprises generating the object identifier for each object based on the data pointer.

42. A processing system as recited in claim 35, wherein generating the object identifier for each of the objects further comprises concatenating a plurality of strings to form the object identifier of each object.

43. A processing system as recited in claim 42, wherein a first one of the strings is the data pointer.

44. A processing system as recited in claim 43, wherein a second one of the strings represents at least a portion of the meta-data.

45. A processing system as recited in claim 44, wherein the second one of the strings represents version information in the meta-data.

46. A processing system as recited in claim 43, wherein a third one of the strings indicates the position within the set of data of the portion of data stored in the object.

47. A processing system as recited in claim 46, wherein a fourth one of the strings indicates an encoding of the data stored in the object.

48. A method of storing media data in a cache, the method comprising:

receiving information associated with a data pointer, the information including media data associated with the data pointer and stored by a server;

storing the media data in the cache as a plurality of files, each of the files storing a portion of the media data;

generating a filename for each file in the plurality of files based upon the portion of the media data stored by each file, wherein the filename for each object unambiguously identifies the portion of the media data stored by the file relative to any other data associated with the data pointer; and

storing mapping information that maps each of the files to the corresponding filename, wherein each of the files is individually accessible from the cache using the filename generated for the file.

49. A method as recited in claim 48, wherein the information associated with the data pointer further comprises meta-data related to properties of the media data, and wherein the second object identifier further is generated based on the media data meta-data.

50. A method of storing media data in a cache, the method comprising:

receiving information associated with a data pointer, the information comprising media data associated with the data pointer and stored by a server;

partitioning the media data into a plurality of portions such that each portion includes media data of a predetermined time duration;

storing each portion in the cache as an object, to store a plurality of objects in the cache;

generating a first object identifier for each of the objects based upon the temporal position of the portion of the media data stored in the object within the media data; and

generating a second object identifier for each of the objects based on the data pointer of the media data and the first object identifier of the object, wherein the second object identifier for each object unambiguously identifies the portion of the media data stored by the object.

51. A method as recited in claim 50, wherein the data pointer is a Uniform Resource Locator (URL).

52. A method as recited in claim 50, wherein the media data comprises streaming media data.

53. A method as recited in claim 50, wherein the information associated with the data pointer further comprises media data meta-data related to properties of the media data.

54. A method as recited in claim 53, wherein the second object identifier further is generated based on the media data meta-data.

55. A method as recited in claim 53, wherein each object in the plurality of objects is individually accessible from the cache using the object identifier generated for the object.

56. A method as recited in claim 50, further comprising:

storing mapping information that maps each object in the plurality of objects to an object identifier generated for the object, wherein the mapping information stores information mapping the object identifier generated for-an object stored in the cache to an object handle of the object.

57. A method as recited in claim 50, wherein:

each object in the plurality of objects is a file in a plurality of files; and

generating an object identifier for each object comprises generating a filename for each file in the plurality of files, wherein the filename for a file identifies the portion of the media data stored by the file.