Communication system and techniques for transmission from source to destination

• US 20030067877A1
• Filed: 09/26/2002
• Published: 04/10/2003
• Est. Priority Date: 09/27/2001
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: EG Technology, Inc. (CommScope Holding Company, Inc.)
• Inventors: Jayant, Nikil, Sivakumar, Raghupathy
• Granted Patent: US 7,218,610 B2
• Time in Patent Office: Days
• US Class Current: 370/232
• CPC Class Codes: H04L 45/30 Routing of multiclass traffic
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/193 at the transport layer, e.g. TCP related
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/2433 Allocation of priorities to traffic types
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/27 Evaluation or update of window size, e.g. using information derived from acknowledged [ACK] packets
• 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: H04L 49/90 Buffering arrangements
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/752 adapting media to network capabilities
• CPC Class Codes: H04L 65/756 adapting media to device capabilities
• CPC Class Codes: H04L 65/762 at the source reformatting of additional data in video distribution servers H04N21/2355
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04N 21/23406 involving management of server-side video buffer
• CPC Class Codes: H04N 21/234327 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/2404 Monitoring of server processing errors or hardware failure error or fault detection G06F11/07; monitoring in general G06F11/30
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/44004 involving video buffer management, e.g. video decoder buffer or video display buffer
• 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 21/631 : Multimode Transmission, e.g. transmitting basic layers and enhancement layers of the content over different transmission paths or transmitting with different error corrections, different keys or with different transmission protocols
• CPC Class Codes: H04N 21/6373 : for rate control , e.g. request to the server to modify its transmission rate flow control in packet networks H04L47/10
• 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 21/6377 : directed to server one-way streaming services wherein the source is controlled by the destination H04L65/613
• CPC Class Codes: H04N 21/64769 : for rate control flow control in packet networks H04L47/10
• CPC Class Codes: H04N 21/64776 : for requesting retransmission, e.g. of data packets lost or corrupted during transmission from server ARQ 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 21/658 : Transmission by the client directed to the server
• CPC Class Codes: Y02D 30/50 : in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A system and method for communicating between source and destination transmission and presentation of streaming digital information signals can be uses to optimize performance in the context of the contentions among different dimensions of performance including goodput, throughput, delay, receiver buffer requirements and tolerance to loss and jitter. The system provides ordering segments of information based on a priority associated with each of the segments of the information; managing of flow of the segments into and out of a buffer based on the priority of the segments of information; adjusting a rate at which information is provided to a communication medium; and transmitting the information.

Claims

1. A method for providing digital communication, comprising:

ordering segments of information based on a priority associated with each of the segments of the information;

managing of flow of the segments into and out of a buffer based on the priority of the segments of information;

adjusting a rate at which information is provided to a communication medium; and

transmitting the information.

2. The method of claim 1, wherein the priority of the segments the information is computed and recomputed based on dependencies between the segments.

3. The method of claim 2;

wherein the computation and recomputation are further based on whether a certain segment can reach a destination by a specified time T_D.

4. The method of claim 3, wherein it is determined that the certain segment cannot reach the destination by the specified time if the specified time T_D is greater than a current time t_c plus a transfer time t_t.

5. The method of claim 4, wherein the certain segment is dropped if the specified time T_D is greater than a current time t_c plus a transfer time t_t.

6. The method of claim 2, wherein the computation and recomputation are further based on capabilities of a destination.

7. The method of claim 6, wherein the capabilities at the destination include whether the destination has a strong post-processing capability.

8. The method of claim 6, wherein the capabilities at the destination include whether the destination can provide error concealment.

9. The method of claim 6, wherein the capabilities at the destination include whether the destination can drop segments of information if a rate of receipt at the destination is less than a transfer rate from the source to the destination.

10. The method of claim 2, wherein the computation and recomputation are further based on connection history between a source and a destination.

11. The method of claim 10, further comprising calculating an expected bandwidth on the communication medium based on an amount of bandwidth previously provided on the communication medium.

12. The method of claim 10, wherein the transmitting the information is performed at a rate within an average bandwidth.

13. The method of claim 10, wherein the transmitting the information is performed at a rate within a lowest bandwidth previously provided on the communication medium.

14. The method of claim 2, wherein the computation and recomputation are further based on rate mismatches between the communication medium and the source.

15. The method of claim 14, further comprising adjusting a rate at which the information is transmitted based on attributes of individual segments of the information.

16. The method of claim 2, wherein the computation of priority takes into account quality of service required at a destination.

17. The method of claim 2, wherein the computation of priority takes into account attributes of the segments of the information.

18. The method of claim 2, wherein the computation of priority takes into account capabilities of the communication medium.

19. The method of claim 18, wherein capabilities of the communication medium include at least one of bandwidth, transmission rate and time for retransmission of a segment of the information.

20. The method of claim 2, wherein the computation of priority takes into account characteristics of the managing of the information held in the buffer.

21. The method of claim 1, wherein managing the information held in a buffer further comprises:

predicting the priority of incoming segments of information to be placed in the buffer; and

determining whether the buffer has sufficient capacity to receive all of the incoming information segments.

22. The method of claim 21, wherein the managing the information held in the buffer further comprises:

dropping segments of information if it is determined that the buffer does not have sufficient capacity to receiving all of the incoming information segments.

23. The method of claim 22, wherein the segments of information that are dropped have a lower priority than the incoming segments of information.

24. The method of claim 21, further comprising:

determining whether segments of information in the buffer have a priority that is one of the same as and lower than the priority of at least one of the incoming segments of information; and

dropping at least one segment of information from the buffer having priority lower than the at least one incoming segment before the at least one incoming segment is received by the buffer if it is determined that the at least one segment of information in the buffer has priority that is one of the same as and lower than the priority of the at least one of the incoming segments.

25. The method of claim 1, further comprising selectively dropping segments of the information.

26. The method of claim 25, wherein dependent segments of the information are dropped if it is determined that the dependent segments depend on a segment that has been dropped.

27. The method of claim 26, wherein one of said segments is dropped if it has a priority lower than another of said segments.

28. The method of claim 1, wherein the rate at which information is provided to the communication medium is calculated using a round trip time and a loss rate on the communication medium.

29. The method of claim 1, wherein the adjusting the rate is based on availability of a communication rate on the communication medium.

30. The method of claim 1, wherein the adjusting of the rate includes accumulating a bandwidth credit for unused bandwidth capacity if the rate at which information is provided to the communication medium is less the rate at which the communication medium is capable of transmitting data.

31. The method of claim 30, wherein the bandwidth credit is the difference between a TCP friendly rate and an actual connection rate on the communication medium.

32. The method of claim 30, further comprising depleting the accumulated credit if the rate at which the information is provided to the communication network is greater than a TCP friendly rate on the communication medium.

33. The method of claim 1, further comprising providing congestion control including

providing a congestion window of f_xx(C_ideal/2), where C_ideal is the ideal congestion window computed as the bandwidth-delay product R*rtt, where rtt is the roundtrip time on the communication medium and R is the data rate of the flow;

increasing the congestion control window by an increase function of a constant x if there is an increase in congestion; and

decreasing the congestion control window by f_yy(Max(0, C_current−

C_ideal)), where C_current is the current congestion control window, if there is a decrease in congestion.

34. The method of claim 1, further comprising providing congestion control including

starting with a congestion window that is an ideal window size;

increasing the congestion window by a function of a constant x; and

decreasing the congestion window by a function of how much the congestion window is larger than the ideal window size.

35. The method of claim 1, further comprising adjusting the ordering of the segments, the managing of the flow of segments into and out of the buffer and the adjusting the rate based on quality of service requirements at a destination.

36. The method of claim 35, wherein the quality of service requirements are provided by a user at the destination.

37. The method of claim 1, further comprising adjusting the ordering of the segments, the managing of the flow of segments into and out of the buffer and the adjusting the rate based on capabilities of devices at a destination.

38. The method of claim 1, further comprising adjusting the ordering of the segments, the managing of the flow of segments into and out of the buffer and the adjusting the rate based on capabilities of the communication medium.

39. The method of claim 1, further comprising providing time synchronization information about the segments to the destination.

40. The method of claim 1, further comprising providing priority signature information about the segments to the destination.