Selective proxy to alleviate adjacent channel interference in full duplex cable network environments

• US 10,361,837 B2
• Filed: 06/16/2017
• Issued: 07/23/2019
• Est. Priority Date: 06/16/2017
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Jin, Hang
• Primary Examiner(s): Zhu, Bo Hui A
• Application Number:
  US15/625,940
• Publication Number:
  US 20180367290A1
• Time in Patent Office: 767 Days
• CPC Class Codes: H04L 1/1858 Transmission or retransmission of more than one copy of acknowledgement message
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end
• CPC Class Codes: H04L 1/1874 Buffer management
• CPC Class Codes: H04L 1/188 Time-out mechanisms
• CPC Class Codes: H04L 1/203 Details of error rate determination, e.g. BER, FER or WER
• CPC Class Codes: H04L 43/026 using flow identification
• CPC Class Codes: H04L 43/0847 Transmission error
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04L 47/31 by tagging of packets, e.g. using discard eligibility [DE] bits
• CPC Class Codes: H04L 5/1461 Suppression of signals in the return path, i.e. bidirectional control circuits

Abstract

A method in an embodiment includes calculating a first packet error rate (PER) of a flow sent from a source to a cable modem over a first period of time in a full duplex cable network, tagging the flow based on determining the first PER satisfies a tag threshold associated with the flow, and intercepting, at a selective proxy, a packet of the tagged flow. The method further includes storing a backup of the packet, transmitting the packet to the cable modem, determining the cable modem did not receive the packet, and retransmitting the backup of the packet to the cable modem. Further embodiments include dynamically calculating a second PER of the tagged flow based on a second period of time, determining the second PER satisfies a de-tag threshold, and revoking the tagging of the flow based, at least in part, on determining the second PER satisfies the de-tag threshold.

Claims

1. A method comprising:

calculating a first packet error rate (PER) of a flow sent from a source to a cable modem over a first period of time in a full duplex cable network;

tagging the flow based on determining the first PER of the flow satisfies a tag threshold associated with the flow;

intercepting, at a selective proxy, a packet of the tagged flow;

storing a backup of the packet;

transmitting the packet to the cable modem;

determining the cable modem did not receive the packet;

retransmitting the backup of the packet to the cable modem;

dynamically calculating a second PER of the tagged flow based on a second period of time that ends after the first period of time ends;

determining the second PER of the tagged flow satisfies a de-tag threshold; and

revoking the tagging of the flow based, at least in part, on determining the second PER satisfies the de-tag threshold.

2. The method of claim 1, wherein the packet of the tagged flow is intercepted by the selective proxy based on the flow being tagged.

3. The method of claim 1, wherein the de-tag threshold is lower than the tag threshold.

4. The method of claim 1, wherein the revoking the tagging of the flow is based, in part, on determining one or more other packet error rates (PERs) of the tagged flow satisfy the de-tag threshold.

5. The method of claim 1, wherein the tag threshold is configured for the flow, and wherein the de-tag threshold is configured for the flow.

6. The method of claim 1, further comprising:

receiving an acknowledgement message from the cable modem indicating the cable modem received the backup packet; and

deleting the stored backup packet.

7. The method of claim 1, wherein the determining the packet was not received by the cable modem includes at least one of receiving a duplicate message indicating a different packet of the flow was received by the cable modem and determining a message acknowledging receipt of the packet was not received from the cable modem within a timeout period.

8. The method of claim 1, wherein the tag threshold is based on at least one of a quality of service (QoS) setting associated with the flow, a service level agreement (SLA) associated with the cable modem, historical data associated with the cable modem, historical data associated with the flow, network traffic type associated with the flow, and an application type associated with the flow.

9. The method of claim 1, further comprising:

prior to determining the cable modem did not receive the packet, sending from the selective proxy to the source of the packet, a message indicating the packet was received by the cable modem.

10. The method of claim 1, further comprising:

prior to determining that the first PER of the flow satisfies a tag threshold, dynamically determining the tag threshold.

11. The method of claim 1, wherein the tag threshold is dynamically determined based, at least in part, on historical data associated with cable modem.

12. The method of claim 1, wherein tagging the flow includes recording an identifier of the flow.

13. At least one non-transitory computer readable media comprising instructions for execution, and when executed by at least one processor, cause the at least one processor to:

calculate a first packet error rate (PER) of a flow sent from a source to a cable modem in a full duplex cable network, wherein calculating the first PER comprises;

calculating a first count of packets from the flow that were not received by the cable modem during the first period of time,

calculating a second count of total packets in the flow that were transmitted to the cable modem during the first period of time, and

determining a ratio of the first count to the second count;

tag the flow based on determining the first PER of the flow satisfies a tag threshold associated with the flow;

intercept, at a selective proxy, a packet of the tagged flow;

store a backup of the packet;

transmit the packet to the cable modem;

determine the cable modem did not receive the packet; and

retransmit the backup of the packet to the cable modem.

14. The at least one non-transitory computer readable claim 13, wherein the instructions, when executed by the at least one processor, cause the at least one processor to:

dynamically calculate a second PER of the tagged flow based on a period of time that ended after the first PER was calculated;

determine the second PER of the tagged flow satisfies a de-tag threshold; and

revoke the tagging of the flow based, at least in part, on determining the second PER satisfies the de-tag threshold.

15. A system comprising:

a memory storage; and

a processing unit coupled to the memory storage, wherein the processing unit is operative to;

calculate a first packet error rate (PER) of a flow sent from a source to a cable modem over a first period of time in a full duplex cable network;

tag the flow based on determining the first PER of the flow satisfies a tag threshold associated with the flow;

intercept, at a selective proxy, a packet of the tagged flow;

store a backup of the packet;

transmit the packet to the cable modem;

determine the cable modem did not receive the packet;

retransmit the backup of the packet to the cable modem;

dynamically calculate a second PER of the tagged flow based on a second period of time that ends after the first period of time ends;

determine the second PER of the tagged flow satisfies a de-tag threshold; and

revoke the tagging of the flow based, at least in part, on determining the second PER satisfies the de-tag threshold.

16. The system of claim 15, wherein the packet of the tagged flow is intercepted by the selective proxy based on the flow being tagged.

17. The system of claim 15, wherein the de-tag threshold is lower than the tag threshold.

18. The system of claim 15, wherein the revoking the tagging of the flow is based, in part, on determining one or more other packet error rates (PERs) of the tagged flow satisfy the de-tag threshold.

19. The system of claim 15, wherein the tag threshold is configured for the flow, and wherein the de-tag threshold is configured for the flow.

20. The system of claim 15, wherein the processing unit is further operative to:

receive an acknowledgement message from the cable modem indicating the cable modem received the backup packet; and

delete the stored backup packet.

21. The system of claim 15, wherein the tag threshold is based on at least one of a quality of service (QoS) setting associated with the flow, a service level agreement (SLA) associated with the cable modem, historical data associated with the cable modem, historical data associated with the flow, network traffic type associated with the flow, and an application type associated with the flow.

22. The system of claim 15, wherein the processing unit is further operative to prior to determining the cable modem did not receive the packet, send from the selective proxy to the source of the packet, a message indicating the packet was received by the cable modem.

23. The system of claim 15, wherein the processing unit is further operative to prior to determining that the first PER of the flow satisfies a tag threshold, dynamically determine the tag threshold.

24. The system of claim 15, wherein the tag threshold is dynamically determined based, at least in part, on historical data associated with cable modem.

25. The system of claim 15, wherein tagging the flow includes recording an identifier of the flow.