Systems and methods for tracking and exporting flows in software with augmented processing in hardware

Patent metadata

Field	Value
Publication number	US-12166650-B2
Application number	US-202318185921-A
Country	US
Kind code	B2
Filing date	Mar 17, 2023
Priority date	May 7, 2021
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

Systems and methods are provided herein for using a network device's software (e.g., programs executed on a CPU) to maintain and export flow data while offloading network resource intensive tasks to the network device's hardware. This may be accomplished by a network device determining whether a new flow should be tracked using only the software table (e.g., table stored only on the CPU) of the network device or whether certain flow tracking tasks (e.g., counting/parsing) can be offloaded to a hardware table (e.g., counter table in a hardware flow cache) of the network device. The network device may use one or more conditions to determine whether the new flow should be tracked using the software table or by both the software and the hardware table. The conditions can relate to the characteristics of the new flow, resource information, prioritization of the new flow, etc.

First claim

What is claimed is:

1. A method performed by a network device, the method comprising:
receiving a data packet, the data packet being associated with a flow;
in response to the flow being a new flow, determining whether or not to track the new flow using a hardware table in the network device based on characteristics related to the new flow and resource information related to the hardware table, wherein characteristics related to the new flow include an activity of the new flow that corresponds to a type of flow to be tracked using the hardware table, wherein the type of flow to be tracked includes flows that send a number of packets during a period of time that exceeds a threshold number of packets; and
in response to a determination to track the new flow using the hardware table:
adding a table entry corresponding to the new flow to the hardware table, wherein flow information contained in received data packets corresponding to the new flow is recorded in the table entry corresponding to the new flow; and
updating a software table with flow information stored in the hardware table on a repeated basis.

2. The method of claim 1 , wherein the resource information related to the hardware table includes a number of flows installed in the hardware table, wherein whether or not to track the new flow using a hardware table includes comparing the number of flows installed in the hardware table to a threshold value.

3. The method of claim 1 , the method further comprising, in response to a determination to track the new flow using only the software table in the network device, recording the flow information related to the new flow only in the software table.

4. The method of claim 1 , the method further comprising, in response to a determination to track the new flow using both the hardware table and the software table in the network device, recording the flow information in the hardware table and the software.

5. The method of claim 1 , wherein the updating is performed periodically.

6. The method of claim 1 , wherein the updating is performed in response to a threshold number of data packets corresponding to the new flow are counted.

7. The method of claim 1 , wherein the flow information includes one or more of: a number of packets in the new flow, a number of bytes in the new flow, ingress and egress interface of the new flow, entry creation time of the table entry corresponding to the new flow, and last time of update of the new flow.

8. A network device comprising:
one or more computer processors; and
a computer-readable storage device comprising instructions that control the one or more computer processors to:
receive a data packet, the data packet being associated with a flow;
determine, in response to the flow being a new flow, whether or not to track the new flow using a hardware table in the network device based on characteristics related to the new flow and resource information related to the hardware table, wherein characteristics related to the new flow include an activity of the new flow that corresponds to a type of flow to be tracked using the hardware table, wherein the type of flow to be tracked includes flows that send a number of packets during a period of time that exceeds a threshold number of packets;
add, in response to a determination to track the new flow using the hardware table, a table entry corresponding to the new flow to the hardware table, wherein flow information contained in received data packets corresponding to the new flow is recorded in the table entry corresponding to the new flow; and
update, in response to the determination to track the new flow using the hardware table, a software table with flow information stored in the hardware table on a repeated basis.

9. The network device of claim 8 , wherein the resource information related to the hardware table includes a number of flows installed in the hardware table, wherein whether or not to track the new flow using a hardware table includes comparing the number of flows installed in the hardware table to a threshold value.

10. The network device of claim 8 , wherein the computer-readable storage device further comprises instructions that control the one or more computer processors to record, in response to a determination to track the new flow using only the software table in the network device, the flow information related to the new flow only in the software table.

11. The network device of claim 8 , wherein the computer-readable storage device further comprises instructions that control the one or more computer processors to record, in response to a determination to track the new flow using both the hardware table and the software table in the network device, the flow information in the hardware table and the software table.

12. The network device of claim 8 , wherein the updating is performed periodically.

13. The network device of claim 8 , wherein the updating is performed in response to a threshold number of data packets corresponding to the new flow are counted.

14. The network device of claim 8 , wherein the flow information includes one or more of: a number of packets in the new flow, a number of bytes in the new flow, ingress and egress interface of the new flow, entry creation time of the table entry corresponding to the new flow, and last time of update of the new flow.

15. A non-transitory computer-readable storage device in a network device, the non-transitory computer-readable storage device having stored thereon computer executable instructions, which when executed, cause the network device to:
receive a data packet, the data packet being associated with a flow;
determine, in response to the flow being a new flow, whether or not to track the new flow using a hardware table in the network device based on characteristics related to the new flow and resource information related to the hardware table, wherein characteristics related to the new flow include an activity of the new flow that corresponds to a type of flow to be tracked using the hardware table, wherein the type of flow to be tracked includes flows that send a number of packets during a period of time that exceeds a threshold number of packets;
add, in response to a determination to track the new flow using the hardware table, a table entry corresponding to the new flow to the hardware table, wherein flow information contained in received data packets corresponding to the new flow is recorded in the table entry corresponding to the new flow; and
update, in response to the determination to track the new flow using the hardware table, a software table with flow information stored in the hardware table on a repeated basis.

16. The non-transitory computer-readable storage device of claim 15 , wherein the resource information related to the hardware table includes a number of flows installed in the hardware table, wherein whether or not to track the new flow using a hardware table includes comparing the number of flows installed in the hardware table to a threshold value.

17. The non-transitory computer-readable storage device of claim 15 , wherein the computer executable instructions, which when executed, further cause the network device to record, in response to a determination to track the new flow using only the software table in the network device, the flow information related to the new flow only in the software table.

18. The non-transitory computer-readable storage device of claim 15 , wherein the computer executable instructions, which when executed, further cause the network device to update

Assignees

• Arista Networks Inc

Inventors

• Labonte Francois
• Kamisetty Jeevan

Classifications

• H04L47/2483 Primary

  involving identification of individual flows · CPC title

• H04L43/026

  using flow identification · CPC title

• H04L43/024

  by adaptive sampling · CPC title

• H04L43/062 Primary

  related to network traffic · CPC title

• H04L43/0876

  Network utilisation, e.g. volume of load or congestion level · CPC title