SYSTEMS AND METHODS FOR PRIORITIZATION OF DATA FOR INTELLIGENT DISCARD IN A COMMUNICATION NETWORK

• US 20120013748A1
• Filed: 09/23/2011
• Published: 01/19/2012
• Est. Priority Date: 06/12/2009
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Cygnus Broadband, Inc. (Quarterhill Inc. (f/k/a Wi-LAN Inc.))
• Inventors: Stanwood, Kenneth, Gell, David, Bao, Yiliang
• Granted Patent: US 8,745,677 B2
• Time in Patent Office: Days
• US Class Current: 348/192
• CPC Class Codes: H04L 41/5022 by giving priorities, e.g. assigning classes of service
• CPC Class Codes: H04L 41/509 wherein the managed service relates to media content delivery, e.g. audio, video or TV
• CPC Class Codes: H04L 47/2408 for supporting different services, e.g. a differentiated services [DiffServ] type of service
• CPC Class Codes: H04L 47/30 in combination with information about buffer occupancy at either end or at transit nodes
• CPC Class Codes: H04L 47/32 by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04N 21/234327 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/2381 Adapting the multiplex stream to a specific network, e.g. an Internet Protocol [IP] network transmission of MPEG streams over ATM H04L12/5601
• CPC Class Codes: H04N 21/64792 Controlling the complexity of the content stream, e.g. by dropping packets intermediate media network packet handling H04L65/765; proxy provisioning conversion or adaptation for reducing the amount or size of exchanged application data H04L67/5651; negotiation of resources in wireless networks H04W28/16
• CPC Class Codes: H04N 21/8451 using Advanced Video Coding [AVC]

Abstract

Capacity and spectrum constrained, multiple-access communication systems optimize performance by selectively discarding packets. Changes in the communication systems may be driven using control responses. Control responses include intelligent discard of network packets under capacity constrained conditions. Packets are prioritized and discard decisions are made based on the prioritization. Various embodiments provide an interactive response by selectively discarding packets to enhance perceived and actual system throughput, provide a reactive response by selectively discarding data packets based on their relative impact to service quality to mitigate oversubscription, provide a proactive response by discarding packets based on predicted oversubscription, or provide a combination thereof. Packets may be prioritized for discard using correlations between discards and bandwidth reduction and quality degradation. The quality degradation for video packets may be measured objectively.

Claims

1. A communication device for managing packet discards in a communication network, the communication device comprising:

a video quality measurement module configured to receive packets containing frames of a video stream and to determine contributions of the frames to quality measurements of the video stream;

a priority assignment module configured to receive the contributions of the frames to the quality measurement of the video stream and assign priorities to the packets utilizing the contributions of the frames to the quality measurements; and

a selection module configured to select at least one of the packets for discard utilizing the assigned priorities and to supply the packets not selected for discard for transmission in the communication network.

2. The communication device of claim 1, wherein the video quality measurement module is further configured to calculate an objective video quality measurement for use in determining the contributions of the frames to the quality measurement of the video stream.

3. The communication device of claim 1, wherein the priority assignment module is further configured to assign the priorities to the packets so that packets having greater contributions to the quality measurements of the video stream are assigned higher priorities.

4. The communication device of claim 1, wherein some of the packets are formatted according to H.264 and include nal_ref_idc fields,

wherein the video quality measurement module is further configured to set values in the nal_ref_idc fields based at least in part on the contributions of the frames to quality measurements of the video stream, and

wherein the priority assignment module is further configured to utilize the values in the nal_ref_idc fields in assigning the priorities to the packets.

5. The communication device of claim 1, wherein the video quality measurement module is further configured to receive indications of the packets selected for discard and to include the indications in determining the contributions of the frames to the quality measurements.

6. The communication device of claim 5, wherein some of the packets are formatted according to H.264 and include nal_ref_idc fields,

wherein the video quality measurement module is further configured to modify values in some of the nal_ref_idc fields based at least in part on the indications of the packets selected for discard, and

wherein the priority assignment module is further configured to utilize the values in the nal_ref_idc fields in assigning the priorities to the packets.

7. A method for operating a communication device for managing packet discards before transmission in a communication network, the method comprising:

receiving packets for transmission, at least some of the packets associated with video streams;

determining a priority for each of the packets, wherein the priority of the packets associated with the video streams includes impacts of discarding the packets associated with the video streams on video quality of the video streams;

determining whether reduced bandwidth should be used to transmit the packets;

selecting, utilizing the determined priorities, at least one of the packets for discard when it is determined that reduced bandwidth should be used to transmit the packets; and

transmitting the packets not selected for discard to the communication network.

8. The method of claim 7, wherein determining the priority for each of the packets comprises calculating a contribution to an objective video quality measurement for each of the packets associated with the video streams.

9. The method of claim 8, wherein the objective video quality measurement is a full-reference video quality measurement.

10. The method of claim 8, wherein the objective video quality measurement is a reduced-reference video quality measurement.

11. The method of claim 8, wherein the objective video quality measurement is a no-reference video quality measurement.

12. The method of claim 7, wherein some of the packets are formatted according to H.264 and include nal_ref_idc fields, and wherein determining a priority for each of the packets includes utilizing values in the nal_ref idc fields for the packets formatted according to H.264.

13. The method of claim 12, wherein determining the priority for each of the packets formatted according to H.264 further includes assigning a lower priority when the associated nal_ref idc field has a zero value.

14. The method of claim 12, further comprising modifying values in the nal_ref_idc fields in other packets related to the packets selected for discard.

15. The method of claim 12, wherein determining the priority for each of the packets associated with the video streams includes analyzing whether the packets include video information that depends on video information in other packets, and further comprising setting values in the nal_ref_idc fields based at least in part on whether the packets include video information that depends on the video information in other packets.

16. The method of claim 7, wherein some of the packets are formatted according to H.264-Scalable Video Coding (SVC) and include priority_id fields, and wherein determining a priority for each of the packets includes utilizing values in the priority_id fields for the packets formatted according to SVC.

17. The method of claim 16, further comprising modifying values in the priority_id fields in other packets related to the packets selected for discard.

18. The method of claim 7, wherein some of the packets are formatted according to H.264-Scalable Video Coding (SVC), and wherein determining the priority of the packets formatted according to SVC utilizes values from dependency_id fields, quality_id fields, temporal_id fields, or combinations thereof.

19. The method of claim 7, wherein the priorities for some of the packets associated with video streams are based at least in part on a characteristic selected from the group consisting of video resolution, video frame rate, video data rate, and combinations thereof.

20. The method of claim 7, wherein the video streams are encoded according to multiple protocols and the priorities of the packets are based at least in part on the protocol associated with the packets immunity to discards.

21. The method of claim 20, wherein the multiple protocols include MPEG-4 and H.264-Scalable Video Coding (SVC) and packets associated with one of the video streams formatted according to MPEG-4 have higher priorities than packets associated with one of the video streams formatted according to SVC.

22. A method for operating a communication device for managing packet discards before transmission in a communication network, the method comprising:

receiving packets for transmission;

assigning a priority for each of the packets, wherein the priorities of the packets include impacts of discarding the packets on quality of services associated with the packets;

placing the packets in queues before transmitting the packets;

determining whether reduced bandwidth should be used to transmit the packets;

selecting, utilizing the determined priorities, at least one of the packets for discard when it is determined that reduced bandwidth should be used to transmit the packets;

transmitting the packets not selected for discard from the queues to the communication network.

23. The method of claim 22, wherein determining whether reduced bandwidth should be used to transmit the packets is based at least in part on a depth of packets in the queues.

24. The method of claim 22, wherein packets in one of the queues are selected for discard when the one of queues is more than a predetermined percentage full.

25. The method of claim 24, wherein packets the number of packets selected for discard increases when the percentage full of the one of the queues is more than a second predetermined percentage full.

26. The method of claim 22, wherein packets are selected for discard when the packets have been in one of the queues for a predetermined time.

27. The method of claim 26, wherein the packets selected for discard when the packets have been in one of the queues for the predetermined time are removed from the one of the queues.

28. The method of claim 27, wherein the predetermined time is greater for packets assigned higher priorities.