Adaptive file delivery system and method
View Patent ↗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 while causing the entire file to be delivered in a predetermined delivery deadline.
1. A method comprising:
determining a minimum transfer rate for transferring a file segment of a remaining portion of a file based in part on a determined size for the remaining portion of the file and an amount of time available to transfer the remaining portion of the file;
determining a maximum transfer rate for transferring the file segment of the remaining portion of the file based in part on the minimum transfer rate and a maximum transfer capacity of a sending system;
sending the file segment of the remaining portion of the file from the sending system to a receiving system;
determining an actual transfer rate that the file segment was sent from the sending system to the receiving system based in part on size of the file segment and an elapsed time between when the file segment was sent from the sending system and when the file segment was received at the receiving system;
determining a wait period based in part on the maximum transfer rate, the minimum transfer rate, and the actual transfer rate;
after receiving the file segment at the receiving system, waiting the wait period before sending an acknowledgement message from the receiving system to the sending system, the acknowledgement message acknowledging receipt of the file segment by the receiving; and
sending the acknowledgement message from the receiving system to the sending system.
2. The method of claim 1 wherein the acknowledgement message further contains a value for the actual transfer rate of the file segment.
3. The method of claim 2 wherein the acknowledgement message further contains a value for an effective transfer rate of the file segment based on the actual transfer time and the wait period.
4. The method of claim 1 wherein the determining the wait period is further based in part on at least one of the following: network congestion and network activity.
5. The method of claim 4 wherein the network congestion and the network activity is determined by a system other than the sending system and the receiving system.
6. The method of claim 1 further comprising sending the minimum transfer rate and the maximum transfer rate from the sending system to the receiving system.
7. The method of claim 1 wherein the determining the maximum transfer rate for transferring the file segment of the remaining portion of the file is based further in part on at least one of the following: throughput measurements and congestion measurements for a network communicatively linking the sending system with the receiving system.
8. The method of claim 1 wherein the determining the maximum transfer rate for transferring the file segment of the remaining portion of the file is based further in part on a plurality of time ordered configuration profiles.
9. The method of claim 1 wherein the determining the maximum transfer rate for transferring the file segment of the remaining portion of the file is based further in part on at least an actual transfer rate of a previously sent file segment.
10. The method of claim 1 further comprising determining the amount of time available to transfer the remaining portion of the file based in part on historical records of past transfers.
11. The method of claim 1 further comprising determining the amount of useful time available to transfer the remaining portion of the file based in part on time based configuration profiles.