Congestion avoidance over a transmission control protocol (TCP) flow that involves one or more devices using active queue management (AQM), based on one or more TCP state conditions

• US 10,419,354 B2
• Filed: 01/27/2017
• Issued: 09/17/2019
• Est. Priority Date: 01/27/2017
• Status: Active Grant

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Inventors: Li, Feng, Chung, Jae Won, Ner, Haim S., Rubinshtein, Eduard
• Primary Examiner(s): Hsu, Alpus
• Assistant Examiner(s): Houshmand, Hooman
• Application Number:
  US15/418,305
• Publication Number:
  US 20180219787A1
• Time in Patent Office: 963 Days
• Field of Search: 370230
• CPC Class Codes: H04L 47/12 Avoiding congestion; Recovering from congestion
• 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 47/283 in response to processing delays, e.g. caused by jitter or round trip time [RTT]
• CPC Class Codes: H04W 28/0273 adapting protocols for flow control or congestion control to wireless environment, e.g. adapting transmission control protocol [TCP] wireless network protocols or protocol adaptations to wireless operation, e.g. wireless application protocol H04W80/00

Abstract

A device can determine a congestion window (CWND) value, associated with a first transmission control protocol (TCP) state, for a TCP flow that involves one or more devices using active queue management (AQM). The first TCP state to cause the CWND value to be increased at a particular rate. The device can determine a round trip time (RTT) value, associated with the first TCP state, for the TCP flow. The device can determine that one or more TCP state conditions are satisfied. The device can classify the TCP flow into a different TCP state. The different TCP state to cause the CWND value to be maintained, decreased, or increased at a rate that is different than the particular rate. The device can transmit one or more packets, associated with the TCP flow, based on classifying the TCP flow into the different TCP state.

Claims

1. A device, comprising:

one or more processors to;

determine a congestion window (CWND) value, associated with a slow start transmission control protocol (TCP) state, for a TCP flow that involves one or more devices using active queue management (AQM),

the slow start TCP state to cause the device to increase the CWND value at a particular rate based on a slow start algorithm;

determine a round trip time (RTT) value, associated with the slow start TCP state, for the TCP flow;

determine whether the CWND value satisfies a first threshold and whether the RTT value satisfies a second threshold;

selectively classify the TCP flow into a different TCP state based on the CWND value and the RTT value,

the different TCP state being different than the slow start TCP state and including one of;

a stable TCP state to cause the device to maintain the CWND value,

 

the TCP flow being classified into the stable TCP state when the CWND value satisfies the first threshold and the RTT value does not satisfy the second threshold, or

a congestion avoidance TCP state to cause the device to increase the CWND value at a rate that is different than the particular rate based on a congestion avoidance algorithm,

 

the TCP flow being classified into the congestion avoidance TCP state when the CWND value satisfies the first threshold and the RTT value satisfies the second threshold;

modify the CWND value, as a modified CWND value, based on selectively classifying the TCP flow into the different TCP state; and

transmit one or more packets, associated with the TCP flow, based on the modified CWND value.

2. The device of claim 1, where the one or more processors, when determining whether the CWND value satisfies the first threshold and whether the RTT value satisfies the second threshold, are to:

determine that the CWND value satisfies the first threshold,

determine that the RTT value does not satisfy the second threshold; and

where the one or more processors, when selectively classifying the TCP flow into the different TCP state, are to;

classify the TCP flow into the stable TCP state based on determining that the CWND value satisfies the first threshold and that the RTT value does not satisfy the second threshold.

3. The device of claim 1, where the one or more processors, when determining whether the CWND value satisfies the first threshold and whether the RTT value satisfies the second threshold, are to:

determine that the CWND value satisfies the first threshold; and

determine that the RTT value satisfies the second threshold; and

where the one or more processors, when selectively classifying the TCP flow into the different TCP state, are to;

classify the TCP flow into the congestion avoidance TCP state based on determining that the CWND value satisfies the first threshold and determining that the RTT value satisfies the second threshold.

4. The device of claim 1, where the different TCP state is the congestion avoidance TCP state;

and

where the one or more processors, when causing the device to increase the CWND value at the rate that is different than the particular rate, are to;

increase the CWND value at a rate that is slower than the particular rate,

the rate that is slower than the particular rate to cause the RTT value to decrease to a value that is lower than an AQM value associated with another device.

5. The device of claim 1, where the one or more processors, when selectively classifying the TCP flow into the different TCP state, are further to:

set a rate for increasing or decreasing the CWND value based on the different TCP state.

6. The device of claim 1, where the one or more processors are further to:

determine whether one or more TCP state conditions are satisfied based on selectively classifying the TCP flow into the different TCP state; and

reclassify the TCP flow into the slow start TCP state, the stable TCP state, or the congestion avoidance TCP state based on determining whether the one or more TCP state conditions are satisfied.

7. The device of claim 6, where the different TCP state is the congestion avoidance TCP state;

where the one or more processors, when determining whether the one or more TCP state conditions are satisfied, are to;

determine that the RTT value does not satisfy another threshold,

verify that the TCP flow has been in the congestion avoidance TCP state for longer than a threshold period of time; and

where the one or more processors, when reclassifying the TCP flow, are to;

reclassify the TCP flow into the slow start TCP state based on determining that the RTT value does not satisfy the other threshold and based on verifying that the TCP flow has been in the congestion avoidance TCP state for longer than the threshold period of time.

8. A non-transitory computer-readable medium storing instructions, the instructions comprising:

one or more instructions that, when executed by one or more processors of a device, cause the one or more processors to;

determine a congestion window (CWND) value, associated with a slow start transmission control protocol (TCP) state, for a TCP flow that involves one or more devices using active queue management (AQM),

the slow start TCP state to cause the CWND value to be increased at a particular rate based on a slow start algorithm;

determine a round trip time (RTT) value, associated with the slow start TCP state, for the TCP flow;

determine whether the CWND value satisfies a first threshold and whether the RTT value satisfies a second threshold;

classify the TCP flow into a different TCP state based on whether the CWND value satisfies the first threshold and whether the RTT value satisfies the second threshold,

the different TCP state being different than the slow start TCP state and including one of;

a stable TCP state to cause the device to maintain the CWND value,

 

the TCP flow being classified into the stable TCP state when the CWND value satisfies the first threshold and the RTT value does not satisfy the second threshold, or

a congestion avoidance TCP state to cause the device to increase the CWND value at a rate that is different than the particular rate based on a congestion avoidance algorithm,

 

the TCP flow being classified into the congestion avoidance TCP state when the CWND value satisfies the first threshold and the RTT value satisfies the second threshold; and

transmit one or more packets, associated with the TCP flow, based on classifying the TCP flow into the different TCP state.

9. The non-transitory computer-readable medium of claim 8, where the one or more instructions, that cause the one or more processors to determine whether the CWND value satisfies the first threshold and whether the RTT value satisfies the second threshold, cause the one or more processors to:

determine that the CWND value satisfies the first threshold

determine that the RTT value does not satisfy the second threshold; and

where the one or more instructions, that cause the one or more processors to classify the TCP flow into the different TCP state, cause the one or more processors to;

classify the TCP flow into the stable TCP state.

10. The non-transitory computer-readable medium of claim 8, where the one or more instructions, that cause the one or more processors to determine whether the CWND value satisfies the first threshold and whether the RTT value satisfies the second threshold, cause the one or more processors to:

compare the CWND value and the first threshold,

compare the RTT value and the second threshold,

determine that the CWND value satisfies the first threshold and that the RTT value does not the second threshold based on a result of comparing the CWND value and the first threshold and a result of comparing the RTT value and the second threshold; and

where the one or more instructions, that cause the one or more processors to classify the TCP flow into the different TCP state, cause the one or more processors to;

classify the TCP flow into the stable TCP state,

the stable TCP state to cause the CWND value to be decreased or to be increased at a rate that is different than the particular rate.

11. The non-transitory computer-readable medium of claim 8, where the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

determine whether one or more TCP state conditions are satisfied based on classifying the TCP flow into the different TCP state; and

reclassify the TCP flow into the slow start TCP state, a stable TCP state, or a congestion avoidance TCP state based on determining whether the one or more TCP state conditions are satisfied.

12. The non-transitory computer-readable medium of claim 11, where the different TCP state is the congestion avoidance TCP state,

where the one or more instructions, that cause the one or more processors to determine whether the one or more TCP state conditions are satisfied, cause the one or more processors to:

determine that the RTT value does not satisfy another threshold,

verify that the TCP flow has been in the congestion avoidance TCP state for longer than a threshold period of time,

determine that a TCP state condition, of the one or more TCP state conditions, is satisfied, based on determining that the RTT value does not satisfy the other threshold and verifying that the TCP flow has been in the congestion avoidance TCP state for longer than the threshold period of time; and

where the one or more processors, when reclassifying the TCP flow, are to;

reclassify the TCP flow into the slow start TCP state.

13. The non-transitory computer-readable medium of claim 8, where the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

increase the CWND value at a rate that is slower than the particular rate,

the rate that is slower than the particular rate to cause the RTT value to decrease.

14. The non-transitory computer-readable medium of claim 8, where the one or more instructions, when executed by the one or more processors, further cause the one or more processors to:

obtain an AQM value, from another device, for the TCP flow;

compare the RTT value and the AQM value; and

verify that the RTT value is lower than the AQM value based on comparing the RTT value and the AQM value.

15. A method, comprising:

determining, by a device, a congestion window (CWND) value, associated with a slow start transmission control protocol (TCP) state, for a TCP flow that involves one or more devices using active queue management (AQM),

the slow start TCP state to cause the device to increase the CWND value at a particular rate based on a slow start algorithm;

determining, by the device, a round trip time (RTT) value, associated with the slow start TCP state, for the TCP flow;

determining, by the device, whether the CWND value satisfies a first threshold and whether the RTT value satisfies a second threshold, based on the CWND value and the RTT value;

classifying, by the device, the TCP flow into another TCP state, based on determining whether the CWND value satisfies the first threshold and whether the RTT value satisfies the second threshold,

the other TCP state including one of;

a stable TCP state to cause the device to maintain the CWND value,

the TCP flow being classified into the stable TCP state when the CWND value satisfies the first threshold and the RTT value does not satisfy the second threshold, or

a congestion avoidance TCP state to cause the device to increase the CWND value at a rate that is different than the particular rate based on a congestion avoidance algorithm,

the TCP flow being classified into the congestion avoidance TCP state when the CWND value satisfies the first threshold and the RTT value satisfies the second threshold;

modifying, by the device, the CWND value, as a modified CWND value, based on classifying the TCP flow into the other TCP state; and

transmitting, by the device, one or more packets, associated with the TCP flow, based on the modified CWND value.

16. The method of claim 15, further comprising:

classifying the TCP flow into the stable TCP state.

17. The method of claim 15, where determining whether the CWND value satisfies the first threshold and whether the RTT value satisfies the second threshold comprises:

determining that the CWND value satisfies a maximum CWND threshold, and

determining that a TCP state condition, of the one or more TCP state conditions, is satisfied based on determining that the CWND value satisfies the maximum CWND threshold.

18. The method of claim 15, further comprising:

determining whether one or more TCP state conditions are satisfied based on classifying the TCP flow into the other TCP state; and

reclassifying the TCP flow into the slow start TCP state, or into the other TCP state, based on determining whether the one or more TCP state conditions are satisfied.

19. The method of claim 18, where determining whether the one or more TCP state conditions are satisfied comprises:

determining that the RTT value does not satisfy another threshold,

verifying that the TCP flow has been in the congestion avoidance TCP state for longer than a threshold period of time,

determining that a TCP state condition, of the one or more TCP state conditions, is satisfied, based on determining that the RTT value does not satisfy the other threshold and verifying that the TCP flow has been in the other TCP state for longer than the threshold period of time; and

where reclassifying the TCP flow comprises;

reclassifying the TCP flow into the slow start TCP state.

20. The method of claim 15, further comprising:

obtaining an AQM value, from another device, for the TCP flow;

comparing the RTT value and the AQM value; and

verifying that the RTT value is lower than the AQM value based on comparing the RTT value and the AQM value.