Coding and packet distribution for alternative network paths in telecommunications networks

• US 20070177579A1
• Filed: 01/27/2006
• Published: 08/02/2007
• Est. Priority Date: 01/27/2006
• Status: Active Grant

• Current Assignee: Avaya Incorporated
• Original Assignee: Avaya Incorporated
• Inventors: Karacali-Akyamac, Bengi, Karol, Mark, Meloche, Jean, Krishnan, P., Krishnakumar, Anjur, Diethorn, Eric
• Granted Patent: US 9,306,852 B2
• Time in Patent Office: Days
• US Class Current: 370/352
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/302 Route determination based on requested QoS
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/38 by adapting coding or compression rate

Abstract

A method and apparatus are disclosed that seek to improve the quality of service that is experienced during the transmission of a stream of packets across one or more paths. In particular, a transmitting node encodes a source stream of data (e.g., audio, video, etc.) into one or more sub-streams, and distributes those sub-streams onto multiple network transmission paths. In accordance with the illustrative embodiment of the present invention, the transmitting node evaluates the quality of service of a first network path that fails to provide a quality-of-service guarantee. When the quality of service of the first network path becomes unsatisfactory, the coding of one or more sub-streams that are being transmitted on a second network path is adjusted. In other words, the coding on a second channel is adjusted in response to the changing conditions on a first channel.

Claims

1. A method comprising:

evaluating the quality of service of a first network path from a first node to a second node through a third node that is not in a second network path, wherein said first network path fails to provide a quality-of-service guarantee;

transmitting a first portion of a stream of packets on said second network path from said first node to said second node through a fourth node that is not in said first network path, wherein said first portion comprises a first sub-stream of encoded data at a first encoded data rate; and

when the quality of service of said first network path is unsatisfactory, transmitting a second portion of said stream of packets on said second network path, wherein said second portion comprises a second sub-stream of encoded data at a second encoded data rate.

2. The method of claim 1 wherein said second encoded data rate is less than said first encoded data rate.

3. The method of claim 1 wherein said second sub-stream can be combined with at least one other sub-stream to improve the quality of the content of said stream of packets.

4. The method of claim 3 further comprising encoding a source stream of data into a plurality of encoded sub-streams, wherein said second portion comprises two or more sub-streams in said plurality.

5. The method of claim 4 wherein said source stream is encoded in accordance with a source coding of either (i) layered coding or (ii) multi-descriptive coding.

6. The method of claim 5 further comprising, when said source coding is layered coding, transmitting the base-layer sub-stream on a third network path that has a guaranteed quality of service.

7. A method comprising:

encoding a source stream of data into;

(i) a first sub-stream according to a first encoded data rate, and

(ii) a second sub-stream according to a second encoded data rate;

evaluating the quality of service of a first network path from a first node to a second node through a third node that is not in a second network path, wherein said first network path fails to provide a quality-of-service guarantee; and

when the quality of service of said first network path is unsatisfactory, transmitting said second sub-stream on a second network path from said first node to said second node through a fourth node that is not in said first network path.

8. The method of claim 7 wherein said second encoded data rate is less than said first encoded data rate.

9. The method of claim 7 wherein said second sub-stream can be combined with at least one other sub-stream to improve the quality of the content of a stream of packets, and wherein said at least one other sub-stream is encoded from said source stream.

10. The method of claim 9 wherein said source stream is encoded in accordance with a source coding of either (i) layered coding or (ii) multi-descriptive coding.

11. The method of claim 10 further comprising, when said source coding is layered coding, transmitting said first sub-stream on a third network path that has a guaranteed quality of service, wherein said first sub-stream is in the base layer of said layered coding.

12. The method of claim 7 further comprising transmitting said first sub-stream on said first network path.

13. The method of claim 7 further comprising, when the quality of service of said first network path is unsatisfactory, transmitting a second portion of said first sub-stream on said second network path, wherein a first portion of said first sub-stream had been transmitted on said first network path.

14. A method comprising:

encoding a first segment of a source stream of data into a first sub-stream according to a first encoded data rate;

evaluating the quality of service of a first network path from a first node to a second node through a third node that is not in a second network path, wherein said first network path fails to provide a quality-of-service guarantee; and

when the quality of service of said first network path is unsatisfactory;

(i) encoding a second segment of said source stream into a second sub-stream according to a second encoded data rate, and

(ii) transmitting said second sub-stream on a second network path from said first node to said second node through a fourth node that is not in said first network path.

15. The method of claim 14 further comprising transmitting said first sub-stream on said second network path.

16. The method of claim 14 further comprising transmitting said first sub-stream on said first network path when the quality of service of said first network path is satisfactory.

17. The method of claim 16 wherein said first segment of said source stream is encoded in accordance with the G.711 protocol, and wherein said second segment of said source stream is encoded in accordance with the G.726 protocol.

18. The method of claim 14 wherein said second encoded data rate is less than said first encoded data rate.

19. The method of claim 14 wherein said second sub-stream can be combined with at least one other sub-stream to improve the quality of the content of a stream of packets, and wherein said at least one other sub-stream is encoded from said source stream.

20. The method of claim 19 wherein said source stream is encoded in accordance with a source coding of either (i) layered coding or (ii) multi-descriptive coding.

21. The method of claim 20 further comprising, when said source coding is layered coding, transmitting said first sub-stream on a third network path that has a guaranteed quality of service, wherein said first sub-stream is in the base layer of said layered coding.