Method and system for streaming digital video content to a client in a digital video network

• US 8,713,195 B2
• Filed: 02/09/2007
• Issued: 04/29/2014
• Est. Priority Date: 02/10/2006
• Status: Active Grant

• Current Assignee: Triton US VP Acquisition, Co.
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Pickens, John, Blattman, Kirk, Sherer, W. Paul
• Primary Examiner(s): EL CHANTI, HUSSEIN A
• Application Number:
  US11/673,484
• Publication Number:
  US 20070192812A1
• Time in Patent Office: 2,636 Days
• Field of Search: 709217-219, 709/223, 709225-226, 709231-232
• US Class Current: 709/232
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/004 by using forward error control H04L1/0618 takes precedence; coding, decoding or code conversion, for error detection or correction H03M13/00
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/007 Unequal error protection for format H04L1/0078; for codes per se H03M13/35
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/18 Automatic repetition systems, e.g. Van Duuren systems
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 2001/0094 Bus
• CPC Class Codes: H04L 49/203 ATM switching fabrics with multicast or broadcast capabilities
• CPC Class Codes: H04N 21/23406 involving management of server-side video buffer
• CPC Class Codes: H04N 21/2668 Creating a channel for a dedicated end-user group, e.g. insertion of targeted commercials based on end-user profiles information retrieval from the Internet by querying with filtering and personalisation G06F16/9535; arrangements for replacing or switching information during the broadcast H04H20/10; push services over packet-switching network H04L12/1859; adaptation of message content in packet-switching networks H04L51/063
• CPC Class Codes: H04N 21/4383 Accessing a communication channel
• CPC Class Codes: H04N 21/4384 involving operations to reduce the access time, e.g. fast-tuning for reducing channel switching latency
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• CPC Class Codes: H04N 21/44016 involving splicing one content stream with another content stream, e.g. for substituting a video clip
• CPC Class Codes: H04N 21/44209 Monitoring of downstream path of the transmission network originating from a server, e.g. bandwidth variations of a wireless network arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896
• CPC Class Codes: H04N 21/6125 involving transmission via Internet transmission by internet of broadcast information H04H60/82
• CPC Class Codes: H04N 21/6375 for requesting retransmission , e.g. of data packets lost or corrupted during transmission from serverARQ protocols H04L1/18; implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP] H04L69/16
• CPC Class Codes: H04N 21/6405 Multicasting data broadcast and multicast in packet switching networks H04L12/18
• CPC Class Codes: H04N 21/6408 : Unicasting
• CPC Class Codes: H04N 7/17318 : Direct or substantially direct transmission and handling of requests

Abstract

A technique for streaming digital video content to a client involves providing a new stream of digital video content to the client using forward error correction (FEC) for a limited initial period and then ending the use of FEC after the limited initial period has ended. In an embodiment, during the limited initial period, the digital video content is provided to the client at a rate that is slightly higher than the playout rate in order to allow a client buffer to accumulate digital video content. FEC continues to be used until the client buffer is sufficiently populated such that lost or damaged frames can be retransmitted to the client before the corresponding digital video content is needed for playout. Once the client buffer is sufficiently populated, FEC is ended and retransmission is used to maintain the quality of the streamed digital video content.

Claims

1. A method for streaming digital video content to clients in a digital video network, the method comprising:

identifying a new stream of digital video content that is intended for a client;

providing the new stream to the client using forward error correction for a limited initial period; and

ending the use of forward error correction after the limited initial period while continuing to provide the new stream to the client.

2. The method of claim 1 further comprising, while forward error correction is in use, providing digital video content to the client at a rate that is higher than the playout rate at the client in order to populate a buffer at the client.

3. The method of claim 2 wherein the limited initial period ends once the buffer is populated to a pre-established threshold.

4. The method of claim 2 further comprising reducing the rate at which digital video content is provided to the client to the playout rate and initiating a retransmission protocol once the limited initial period ends.

5. The method of claim 1 wherein the limited initial period ends when a buffer at the client is populated to a pre-established threshold.

6. The method of claim 5 wherein the pre-established threshold is a function of the time required to recover a frame at the client using a retransmission protocol.

7. The method of claim 5 wherein the pre-established threshold provides enough buffered digital video content to enable a frame to be recovered at the client before the frame is due for playout at the client.

8. The method of claim 1 wherein the limited initial period ends upon the expiration of a pre-established time interval.

9. A method for servicing channel change requests in a digital video network that is capable of distributing digital video content to clients via multicasting and unicasting, the method comprising:

detecting a channel change request related to a client;

providing digital video content related to the requested channel to the client in response to the channel change request, wherein providing digital video content to the client comprises using forward error correction for a limited initial period; and

ending the use of forward error correction after the limited initial period while continuing to provide digital video content related to the requested channel to the client.

10. The method of claim 9 further comprising, while forward error correction is in use, providing digital video content to the client at a rate that is higher than the playout rate at the client in order to populate a buffer at the client.

11. The method of claim 10 wherein the limited initial period ends once the buffer is populated to a pre-established threshold.

12. The method of claim 11 further comprising reducing the rate at which digital video content is provided to the client to the playout rate once the buffer is populated to the pre-established threshold.

13. The method of claim 9 wherein the limited initial period ends when a buffer at the client is populated to a pre-established threshold.

14. The method of claim 13 wherein the pre-established threshold is a function of the time required to recover a frame at the client using a retransmission protocol.

15. The method of claim 13 wherein the pre-established threshold provides enough buffered digital video content to enable a frame to be recovered at the client before the frame is due for playout at the client.

16. The method of claim 10 further comprising initiating a retransmission protocol once the limited initial period ends.

17. The method of claim 9 wherein the limited initial period ends when digital video content related to the requested channel is switched from being provided to the client via unicasting to being provided to the client via multicasting.

18. A method for servicing channel change requests in a digital video network that is capable of distributing digital video content to clients via multicasting and unicasting, the method comprising:

detecting a channel change request related to a client;

providing digital video content related to the requested channel to the client in response to the channel change request, wherein providing digital video content to the client comprises using forward error correction for a limited initial period to improve the bit error ratio of digital video content received at the client; and

after the limited initial period, using a retransmission protocol to improve the bit error ratio of digital video content received at the client.

19. The method of claim 18 further comprising, before the end of the limited initial period, providing digital video content to the client at a rate that is greater than the playout rate at the client.

20. The method of claim 18 wherein the limited initial period ends when a buffer at the client is populated to a pre-established threshold.

21. The method of claim 18 further comprising ending the use of forward error correction after the limited initial period.

22. The method of claim 18 further comprising reducing the strength of forward error correction after the limited initial period.

23. A system for streaming digital video content to clients in a digital video network, the system comprising:

a processor; and

memory, the memory storing a transmit module configured to;

provide digital video content related to a new stream to a client using forward error correction for a limited initial period; and

end the use of forward error correction after the limited initial period while continuing to provide digital video content related to the new stream to the client.

24. The system of claim 23 wherein the limited initial period ends when a buffer at the client is populated to a pre-established threshold and wherein the pre-established threshold provides enough buffered digital video content to enable a frame of the new stream to be recovered at the client using a retransmission protocol before the frame is due for playout at the client.

25. The system of claim 24 wherein the transmit module is further configured to reduce the rate at which digital video content is provided to the client to the playout rate once the buffer is populated to the pre-established threshold.

26. The system of claim 23 wherein the transmit module is further configured to provide, while forward error correction is in use, digital video content to the client at rate that is higher than the playout rate at the client in order to populate a buffer at the client.

27. The system of claim 23 wherein the transmit module is configured to use a retransmission protocol once the limited initial period ends.