SYSTEM AND METHOD FOR FLOW CONTROL IN AN ADAPTIVE FILE DELIVERY SYSTEM

• US 20100274872A1
• Filed: 07/07/2010
• Published: 10/28/2010
• Est. Priority Date: 04/07/2005
• Status: Active Grant

• Current Assignee: Opanga Networks, Inc.
• Original Assignee: Opanga Networks, Inc.
• Inventors: Gibbons, David B., Harrang, Jeffrey Paul, Burnette, John Michael
• Granted Patent: US 8,589,508 B2
• Time in Patent Office: Days
• US Class Current: 709/217
• CPC Class Codes: H04L 1/0002 by adapting the transmission rate
• CPC Class Codes: H04L 1/0038 Blind format detection for detection of modulation format H04L27/0012
• CPC Class Codes: H04L 1/1671 the supervisory signal being transmitted together with control information
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/11 Identifying congestion
• CPC Class Codes: H04L 47/19 at layers above the network layer network arrangements for networked applications for scheduling or organising the servicing of application requests H04L67/60
• CPC Class Codes: H04L 47/263 Rate modification at the source after receiving feedback
• CPC Class Codes: H04L 47/283 in response to processing delays, e.g. caused by jitter or round trip time [RTT]
• CPC Class Codes: H04L 47/35 by embedding flow control information in regular packets, e.g. piggybacking
• CPC Class Codes: H04L 47/365 Dynamic adaptation of the packet size
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/303 Terminal profiles
• CPC Class Codes: H04L 67/62 Establishing a time schedule for servicing the requests

Abstract

An adaptive file delivery system and method transmits a data file, such as an audio-video file, over a network or collection of networks in segments, each segment transmitted during a different time period. Each time period has a transmission portion to transmit its associated file segment and a wait portion in which no further interaction with the network occurs regarding the transmitted segment. In some implementations, the duration of the transmission portion of each time period is sufficient to reach a steady-state throughput condition, which allows the traffic load status of the network or networks to be determined from rate measurements of file segment transmissions. The duration of the wait portion of each time period is at least long enough to limit the average rate of file segment transmission to adapt to network traffic load variations and avoid network congestion. Various techniques for measuring congestion are described.

Claims

1. A method for transferring a file from a sending system to a receiving system, comprising:

sending a file made up of a plurality of file segments from the sending system along a file transmission path to the receiving system, the sending of the file including sending the file segments by a plurality of transmissions spaced out in time with a variable wait period occurring after the transmission of each of the plurality of file segments;

determining a congestion level along the file transmission path; and

controlling the transmission of subsequent file segments by determining the variable wait period based in part on the determined congestion level.

2. The method of claim 1 wherein controlling the transmission of subsequent file segments is performed by the receiving system.

3. The method of claim 2 wherein the receiving system measures the wait period and sends a request for a subsequent file segment to the sending system upon expiration of the wait period.

4. The method of claim 2 wherein the receiving system sends an acknowledgement message to the sending system upon expiration of the wait period, the acknowledgement message acknowledging successful reception of the prior file segment and including a request for a subsequent file segment.

5. The method of claim 2, further comprising the receiving system calculating the wait period and sending a request for a subsequent file segment to the sending system upon expiration of the wait period.

6. The method of claim 2, further comprising the receiving system calculating a segment size for a subsequent file segment and sending an acknowledgement message to the sending system upon expiration of the wait period, the acknowledgement message acknowledging successful reception of the prior file segment and including a request for a subsequent file segment having a file segment size specified in the acknowledgement message.

7. The method of claim 6 wherein the receiving system calculates the segment size for a subsequent file segment based at least in part on the determined congestion level.

8. The method of claim 1 wherein controlling the transmission of subsequent file segments is performed by the sending system.

9. The method of claim 8 wherein the sending system measures the wait period and sends a subsequent file segment to the receiving system upon expiration of the wait period.

10. The method of claim 8 wherein the receiving system sends an acknowledgement message to the sending system upon receipt of the file segment, the acknowledgement message acknowledging successful reception of the prior file segment.

11. The method of claim 8, further comprising the sending system calculating the wait period and sending the subsequent file segment to the receiving system upon expiration of the wait period.

12. The method of claim 11 wherein the sending system calculates the wait period for the subsequent file segment based at least in part on the determined congestion level.

13. The method of claim 11 wherein the wait period for the subsequent file segment increases as the determined congestion level increases.

14. The method of claim 11, further comprising the sending system sending the file segment with time data indicating a transmit time of transmission of the file segment from the sending system and the receiving system sending an acknowledgement message to the sending system acknowledging receipt of the file segment and including data indicating a transit time to transmit the file segment from the sending system to the receiving system, the transit time being indicative of the congestion level.

15. The method of claim 14 wherein the acknowledgement message includes data indicating a receipt time that the receiving system receives the file segment from the sending system, the sending system calculating the transit time based on the transmit time data and the receipt time data.

16. The method of claim 14, further comprising the receiving system calculating the transit time based on the transmit time data and a receipt time that the receiving system receives the file segment from the sending system wherein the acknowledgement message includes the transit time calculated by the receiving system.

17. The method of claim 8, further comprising the sending system calculating a segment size for the subsequent file segment and sending the subsequent file segment having calculated file segment size upon expiration of the wait period.

18. The method of claim 17 wherein the sending system calculates the segment size for a subsequent file segment based at least in part on the determined congestion level.

19. A system to transmit a data file made up of a plurality of file segments to a receiving computing system, comprising:

a data storage element configured to store the data file to be transmitted to the receiving computing system;

a network interface communicatively coupled to the data storage element and configured to receive the data file therefrom, the network interface being further configured to transmit the plurality of data file segments to the receiving system via a communications network;

a network interface controller configured to control transmission of the plurality of file segments to the receiving system via the network interface, the network interface controller being configured to have a wait period between transmission of individual ones of the plurality of file segments based in part on a level of network congestion in the communication network.

20. The system of claim 19 wherein the network interface controller is configured to receive a request for transmission of a subsequent file segment from the receiving computer system upon expiration of the wait period.

21. The system of claim 20 wherein the request for transmission of a subsequent file segment from the receiving computer system includes a request for a subsequent file segment having a file segment size specified in the request for transmission, the network interface controller being configured to send the next subsequent file segment of the requested file segment size upon receipt of the request from the receiving computing system.

22. The system of claim 19 wherein the network interface controller is configured to measure the wait period and to cause the network interface to send a next subsequent file segment upon expiration of the wait period measured by the network interface controller.

23. The system of claim 22 wherein the network interface controller is configured to receive an acknowledgement message from the receiving computer system upon receipt of the file segment and prior to the expiration of the wait period.

24. The system of claim 22 wherein the network interface controller is further configured to calculate the wait period for the subsequent file segment based at least in part on the determined congestion level.

25. The system of claim 24 wherein the wait period for the subsequent file segment increases as the determined congestion level increases.

26. The system of claim 24 wherein the network interface controller is further configured to send the file segment with time data indicating a transmit time of transmission of the file segment from the network interface and to receive an acknowledgement message from the receiving computing system, the acknowledgement message including data indicating a transit time to transmit the file segment from the to the receiving computing system, the transit time being indicative of the congestion level.

27. A computer readable medium containing computer instructions that cause a processor to:

send a file made up of a plurality of file segments from a sending system along a file transmission path to a receiving system, the sending of the file including sending the file segments by a plurality of transmissions spaced out in time with a variable wait period occurring after the transmission of each of the plurality of file segments;

determine a congestion level along the file transmission path; and

control the transmission of subsequent file segments by determining the variable wait period based in part on the determined congestion level.

28. The computer readable medium of claim 27, further comprising computer instructions that cause the processor to measure the wait period and send a subsequent file segment to the receiving system upon expiration of the wait period.

29. The computer readable medium of claim 27, further comprising computer instructions that cause the processor to calculate the wait period for the subsequent file segment based at least in part on the determined congestion level.

30. The computer readable medium of claim 27, further comprising computer instructions that cause the processor to send the file segment with time data indicating a transmit time of transmission of the file segment from the sending system and receive an acknowledgement message from the receiving system acknowledging receipt of the file segment and including data indicating a transit time to transmit the file segment from the sending system to the receiving system, the transit time being indicative of the congestion level.

31. The computer readable medium of claim 27, further comprising computer instructions that cause the processor to calculate a segment size for the subsequent file segment and to send the subsequent file segment having calculated file segment size upon expiration of the wait period.

32. The computer readable medium of claim 31 wherein the computer instructions cause the processor to calculate the segment size for a subsequent file segment based at least in part on the determined congestion level.