Systems and methods for prioritization of data for intelligent discard in a communication network

• US 8,745,677 B2
• Filed: 09/23/2011
• Issued: 06/03/2014
• 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
• Primary Examiner(s): Taylor, Joshua
• Assistant Examiner(s): Ocak, Adil
• Application Number:
  US13/243,507
• Publication Number:
  US 20120013748A1
• Time in Patent Office: 984 Days
• Field of Search: None
• US Class Current: 725/95
• 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 base station for managing transmission of packets over a communication link in a communication network, the base station comprising:

a transmission module configured to transmit packets over the communication link;

a video quality measurement module configured to obtain packets containing frames of a video stream from a backhaul port, the frames comprising multiple frame groups, and to determine estimated contributions of a discard of all frames of each frame group to at least one video quality measurement of the video stream;

a priority assignment module configured to receive the estimated contributions of each frame group to the at least one quality measurement and to assign a priority to each of the packets based at least on the frame groups associated with the frames in the respective packet; 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 to the transmission module for transmission over the communication link,

wherein the video quality measurement module is further configured to receive indications of the packets that are selected for discard and to include the indications in determining the contributions of the frames comprising packets that have not yet been selected for discard to the at least one video quality measurement, and

wherein the priority assignment module is further configured to utilize the contributions of frames comprising packets that have not yet been selected for discard to the at least one video quality measurement in assigning the priorities to the packets not yet selected for discard.

2. The base station of claim 1, wherein the video quality measurement module is further configured to calculate the at least one video quality measurement of the video stream.

3. The base station of claim 1, wherein the priority assignment module is further configured to assign the priority to each packet so that a packet having a frame associated with a frame group that has a greater contribution to the at least one video quality measurement of the video stream is assigned a higher priority.

4. The base station of claim 1, wherein some of the packets contain frames that are formatted according to H.264 and that 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 the at least one video quality measurement 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 base station of claim 1, wherein some of the packets contain frames that are formatted according to H.264 and that 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.

6. A method for operating a base station for managing transmission of packets over a communication link in a communication network, the method comprising:

obtaining packets for transmission from a backhaul port, at least one of the packets being associated with a video stream;

determining a priority for each of the packets, wherein the determination the priority for the at least one of the packets associated with a video stream is based at least in part on an estimated contribution of discarding the at least one of the packets to a video quality measurement of the associated video stream;

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

selecting, based at least in part on the determined priority for each of the packets, at least one of the packets for discard when it is determined that a reduced bandwidth should be used to transmit the packets; and

providing the packets not selected for discard for transmission over the communication link,

wherein the estimated contribution of discarding the at least one of the packets for packets that have not yet been selected for discard to the video quality measurement of the associated video stream is determined at least in part on an indication of the at least one of the packets selected for discard, and

wherein determining the priority for the packets that have not yet been selected for discard includes utilizing the estimated contribution of discarding the at least one of the packets for packets that have not yet been selected for discard to the video quality measurement of the associated video stream.

7. The method of claim 6, 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 a video stream.

8. The method of claim 6, wherein some of the packets contain frames that are formatted according to H.264 and that 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 containing frames that are formatted according to H.264.

9. The method of claim 6, wherein some of the packets contain frames that are formatted according to H.264-Scalable Video Coding (SVC) and that 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 containing frames that are formatted according to SVC.

10. The method of claim 6, wherein some of the packets contain frames that 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 at least one of dependency_id fields, quality_id fields, or temporal_id fields.

11. The method of claim 6, wherein the determined priority for each of the at least one of the packets associated with a video stream is based at least in part on a characteristic selected from the group consisting of a video resolution, a video frame rate, and a video data rate.

12. The method of claim 6, wherein each video stream is encoded according to at least one of multiple protocols and the determined priority of each packet is based at least in part on the protocol of the video stream associated with the packet.

13. The method of claim 7, wherein the objective video quality measurement is a full-reference video quality measurement.

14. The method of claim 7, wherein the objective video quality measurement is a reduced-reference video quality measurement.

15. The method of claim 7, wherein the objective video quality measurement is a no-reference video quality measurement.

16. The method of claim 8, wherein determining the priority for each of the packets containing frames that are formatted according to H.264 further includes assigning a lower priority when the associated nal_ref_idc field has a zero value.

17. The method of claim 8, further comprising modifying values in the nal_ref_idc fields in frames of other packets that are related to frames in the packets selected for discard.

18. The method of claim 8, wherein determining the priority for each of the packets associated with a video stream includes analyzing whether the packets include frames having video information that depends on video information in frames of other packets, and further comprising setting values in the nal_ref_idc fields based at least in part on whether the packets include frames having video information that depends on the video information in frames of other packets.

19. The method of claim 9, further comprising modifying values in the priority_id fields in frames of other packets that are related to frames in the packets selected for discard.

20. The method of claim 12, wherein the multiple protocols include MPEG-4 and H.264-Scalable Video Coding (SVC) and wherein a packet that is associated with a video stream formatted according to the MPEG-4 protocol has a higher priority than a packet that is associated with a video stream formatted according to the SVC protocol.

21. A method for operating a base station for managing transmission of packets over a communication link in a communication network, the method comprising:

obtaining packets from a backhaul port for transmission;

assigning a priority for each of the packets, wherein the assigned priority for each packet is determined based at least in part on an estimated contribution of discarding the packet to a service quality measurement for the service associated with the packet;

placing each packet into one of multiple queues before transmitting the packets;

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

selecting, based at least in part on the assigned priority of each packet, at least one of the packets for discard when it is determined that a reduced bandwidth should be used to transmit the packets; and

providing the packets not selected for discard for transmission over the communication link,

wherein the estimated contribution of discarding the packet for packets that have not yet been selected for discard to the service quality measurement is determined at least in part on an indication of the at least one of the packets selected for discard, and

wherein assigning the priority for packets that have not yet been selected for discard includes utilizing the estimated contribution of discarding the packet for packets that have not yet been selected for discard to the service quality measurement.

22. The method of claim 21, wherein determining whether a reduced bandwidth should be used to transmit the packets is based at least in part on a pending number of packets in each of the queues.

23. The method of claim 21, wherein at least one of the packets in one of the queues are selected for discard when the one of the queues is more than a predetermined percentage full.

24. The method of claim 21, wherein packets are selected for discard when the packets have been present in one of the queues for a predetermined time.

25. The method of claim 23, wherein the number of the at least one of the 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 24, wherein the packets selected for discard when the packets have been present in one of the queues for the predetermined time are removed from the one of the queues.

27. The method of claim 26, wherein the predetermined time is greater for a packet that is assigned a higher priority.