Fragmentation of a file for instant access

• US 7,937,379 B2
• Filed: 03/09/2005
• Issued: 05/03/2011
• Est. Priority Date: 03/09/2005
• Status: Active Grant

• Current Assignee: NBC Universal Media LLC (Comcast Corporation)
• Original Assignee: Vudu Incorporated (Comcast Corporation)
• Inventors: Rossmann, Alain, Miranz, Tony, Matloub, Shahriyar, Ganesan, Prasanna
• Primary Examiner(s): Breene; John
• Assistant Examiner(s): Jami; Hares
• Application Number:
  US11/076,214
• Publication Number:
  US 20060206889A1
• Time in Patent Office: 2,246 Days
• Field of Search: 707/100, 707/802, 707/803, 707/999.1, 707/705, 707/736, 725/2, 725/86, 725/87, 725/101, 725/102, 725/103
• US Class Current: 707/705
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/61 taking into account QoS or priority requirements
• CPC Class Codes: H04N 21/4331 Caching operations, e.g. of an advertisement for later insertion during playback
• CPC Class Codes: H04N 21/632 using a connection between clients on a wide area network, e.g. setting up a peer-to-peer communication via Internet for retrieving video segments from the hard-disk of other client devices broadcast-related systems characterised by transmission among terminal devices H04H60/80; distributed application using peer-to-peer [P2P] networks H04L67/104
• CPC Class Codes: H04N 21/8456 by decomposing the content in the time domain, e.g. in time segments
• CPC Class Codes: H04N 7/17318 Direct or substantially direct transmission and handling of requests

Abstract

Techniques for fragmenting a file or a collection of media data are disclosed. According one aspect of the techniques, a file pertaining to a title is fragmented into a header and several tails or segments. The header is a continuous portion of the file while the segments are respective parts of the remaining portion of the file. The header is seeded substantially in all boxes, and none, one or more of the segments are distributed in each of the boxes in service. When a title is ordered, the header is instantly played back while the segments, if not locally available, are continuously fetched respectively from other boxes that have the segments.

Claims

1. A method, performed by one or more processors, for fragmenting a data file pertaining to a media content for distribution to a plurality of devices coupled to a network, the method comprising:

dividing a first portion of the data file into a plurality of segments, wherein the data file includes a sequence of data blocks that are ordered for playback of the media content;

making a determination as to the popularity of the data file;

based, at least in part, on the determination, assigning the plurality of segments of the data file to a first band or a second band, wherein the first band is used for more popular data files than the second band;

distributing each of the plurality of segments for storage in two or more devices of the plurality of devices such that none of the plurality of devices stores the entire data file, wherein each of the plurality of devices is enabled to request playback of the media content, and wherein the number of devices of the two or more devices that store each of the plurality of segments depends on the plurality of segments being assigned to the first band or the second band;

seeding each of the plurality of devices with a header object; and

enabling a first device of the plurality of devices to (i) instantly playback the media content using the seeded header object in response to a request, and (ii) once playback is initiated, continuously play back the media content by configuring the first device to concurrently retrieve two or more segments of the plurality of segments over the network from at least one other device of the plurality of devices, wherein the data blocks forming each of the plurality of segments are non-consecutive with respect to the ordered sequence.

2. The method as recited in claim 1, wherein enabling a first device of the plurality of devices to continuously play back the media content comprises configuring the first device to initiate playback of the media content using the header object while concurrently retrieving the two or more segments over the network from the at least one other device.

3. The method as recited in claim 2, wherein a duration of playback using the header object is greater than a duration of time needed to retrieve parts of the two or more segments over the network.

4. The method as recited in claim 2, wherein a duration of playback using the header object is greater than a combined duration of:

(i) a duration of time needed to retrieve parts of the two or more segments over the network, and (ii) a duration of time needed to synchronize the two or more segments being retrieved over the network.

5. The method as recited in claim 1, further comprising encrypting the header object and the plurality of segments before distributing the header object and the plurality of segments to the plurality of devices.

6. The method as recited in claim 1, wherein the first device uses a locally stored data buffer to play back the media content.

7. The method as recited in claim 6, wherein the buffer initially comprises data blocks from the header object when playback of the first media content is initiated by the first device.

8. The method as recited in claim 7, wherein, while concurrently receiving the two or more segments, the first device is configured to place data blocks from the two or more segments into the data buffer as they are being retrieved.

9. The method as recited in claim 1, wherein data blocks in the data buffer are arranged in the same order as the ordered sequence pertaining to the data file.

10. The method as recited in claim 9, wherein one of the two or more distributed segments pertains to audio data of the media content in a preferred language.

11. The method as recited in claim 1, further comprising:

receiving authentication information from the first device;

determining from the authentication information whether the first device is authorized to play back the media content;

after determining that the first device is authorized to play back the media content, transmitting security information to the first device to allow the header object and the plurality of segments to be decrypted.

12. The method as recited in claim 1, wherein the plurality of segments are not of equal length.

13. The method as recited in claim 1, wherein dividing the first portion of the data file into a plurality of segments comprises simultaneously decimating the first portion of the data file into the plurality of segments.

14. A computing system configured to fragment a data file pertaining to a media content for distribution to a plurality of devices on a network, the one or more computing devices comprising:

a memory module to store program code;

a processor configured to;

divide a first portion of the data file into a plurality of segments, wherein the data file includes a sequence of data blocks that are ordered for playback of media content;

make a determination as to the popularity of the data file;

based, at least in part, on the determination, assign the plurality of segments of the data file to a first band or a second band, wherein the first band is used for more popular data files than the second band;

distribute each of the plurality of segments for storage in two or more devices of the plurality of devices such that none of the plurality of devices stores the entire data file, wherein each of the plurality of devices is enabled to request playback of the media content, and wherein the number of devices of the two or more devices that store each of the plurality of segments depends on the plurality of segments being assigned to the first band or the second band;

seed each of the plurality of devices with a header object; and

enable a first device of the plurality of devices to (i) instantly playback the media content using the seeded header object in response to a request, and (ii) once playback is initiated, continuously play back the media content by configuring the first device to concurrently retrieve two or more segments of the plurality of segments over the network from at least one other device of the plurality of devices, wherein the data blocks forming each of the plurality of segments are non-consecutive with respect to the ordered sequence.

15. The computing system as recited in claim 14, wherein the two or more segments being concurrently retrieved by the first device are multiplexed into a data buffer.

16. The computing system as recited in claim 15, wherein one of the distributed objects pertains to audio data.

17. The computing system as recited in claim 14, wherein the media content is one or more of (i) a movies, (ii) news footage, (iii) a commercial video, and (iv) a game.