Erasure-coded content assembly and retransmission

• US 20100094965A1
• Filed: 10/14/2009
• Published: 04/15/2010
• Est. Priority Date: 10/15/2008
• Status: Abandoned Application

• Current Assignee: Patentvc Limited
• Original Assignee: Patentvc Limited
• Inventors: Thieberger, Gil, Zuckerman, Gal
• Application Number:
  US12/579,386
• Publication Number:
  US 20100094965A1
• Time in Patent Office: Days
• US Class Current: 709/219
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

Methods and systems for erasure-coded content assembly and retransmission, including assembling servers located at or close to edges of the Internet and spread over a wide area, fractional-storage CDN servers located close to or on the Internet backbone, and client devices spread over a wide area. Each assembling server obtains from the CDN servers erasure-coded fragments associated with segments of streaming content according to an order that enables the assembling server to start streaming the content to its associated clients shortly after reconstructing the first segment.

Claims

1. ) A streaming system comprising:

assembling servers located at or close to the edges of the Internet and spread over a wide area, fractional-storage CDN servers located close to or on the Internet backbone, and client devices spread over a wide area;

each assembling server is configured to obtain from the CDN servers erasure-coded fragments associated with segments of streaming content according to an order that enables the assembling server to start streaming the content to its associated clients shortly after reconstructing the first segment.

2. ) The streaming system of claim 1, wherein the assembling servers are configured to obtain the fragments using a fragment pull protocol.

3. ) The streaming system of claim 2, wherein at least one of the assembling servers is located at a juncture of an Internet transit network and a last mile network coupled to at least one of the client devices.

4. ) The streaming system of claim 1, wherein the assembling servers are configured to operate a pull protocol to obtain the fragments from the fractional-storage CDN servers, operate a streaming protocol to stream the reconstructed segments to the client devices, and start streaming while obtaining the fragments.

5. ) The streaming system of claim 4, wherein the fragments pass through a transit network connecting an ISP servicing the client device to the Internet, and the reconstructed segments are streamed through a last mile network connecting the ISP to the client device that is located at a user premises.

6. ) The streaming system of claim 4, wherein the fragments pass through a network connecting the assembling server to its servicing ISP, and the reconstructed segments are streamed through a home network.

7. ) The streaming system of claim 4, wherein the erasure-coding is rateless-coding, and the assembling servers and the client devices are located at a user premises.

8. ) The streaming system of claim 1, wherein the client devices are associated with nearby assembling servers.

9. ) The streaming system of claim 8, wherein the erasure-coding is rateless-coding, the client devices are located at a user premises, and the assembling servers are configured to obtain the fragments using push protocol.

10. ) An apparatus comprising:

an assembling server configured to obtain from fractional-storage CDN servers located close to or on the Internet backbone at least most of the erasure-coded fragments needed to reconstruct a segment of content comprising multiple segments;

the assembling server is further configured to reconstruct the segment and transmit the reconstructed segment or a transcoded version of the segment to a client device.

11. ) The apparatus of claim 10, wherein the segments are approximately sequential segments of streaming content, the fragments are obtained and the segments are reconstructed according to an order that enables the assembling server to start transmitting the segments to the client device using a streaming protocol shortly after reconstructing the first segment, and the transmission at least partially overlaps in time with the obtainment.

12. ) The apparatus of claim 11, wherein the assembling server is configured to obtain the fragments using a fragment pull protocol, and the transmission starts shortly after reconstructing the first segment.

13. ) The apparatus of claim 11, wherein the assembling server is located at or close to the edge of the Internet, and is configured to obtain the fragments using a fragment pull protocol.

14. ) The apparatus of claim 11, wherein the assembling server is located at a juncture of an Internet transit network and a last mile network coupled to the client device, and is configured to obtain the fragments using a fragment pull protocol.

15. ) The apparatus of claim 10, wherein the erasure-coding is rateless-coding;

and the assembling server communicates with the fractional-storage CDN servers via Internet infrastructure that requires an Internet transit fee, and communicates with the client device via a second network that does not require an additional Internet transit fee.

16. ) A method comprising:

receiving, by a first device from fractional-storage servers, erasure-coded fragments associated with segments of streaming content;

reconstructing approximately sequential segments from fragments comprising the received fragments; and

streaming the reconstructed segments or a transcoded version of the segments to a second device shortly after reconstructing the first segment;

wherein the steps of receiving and streaming at least partially overlap in time.

17. ) The method of claim 16, wherein the erasure-coded fragments support source-selection diversity, and the fractional-storage servers are fractional-storage CDN servers located close to or on the Internet backbone.

18. ) The method of claim 17, wherein the erasure-coding is rateless-coding potentially resulting in fragments having a limitless redundancy factor;

and receiving the fragments by the first device comprises receiving the fragments using a fragment pull protocol for high latency.

19. ) The method of claim 17, wherein receiving the fragments by the first device comprises receiving the fragments using a fragment pull protocol for high latency;

and further comprising the second device interacting with the first device as if the first device stores the content locally; and

the first device converting the interactions with the second device into corresponding interactions with the fractional-storage CDN servers.

20. ) The method of claim 19, wherein the interactions between the second device and the first device comprise requests to start streaming content and trick-play instructions.