INGRESS RATE LIMITING

• US 20120163175A1
• Filed: 12/23/2010
• Published: 06/28/2012
• Est. Priority Date: 12/23/2010
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, Inc. (Broadcom, Inc.)
• Inventors: Gupta, Somesh
• Granted Patent: US 8,842,536 B2
• Time in Patent Office: Days
• US Class Current: 370/235
• CPC Class Codes: H04L 47/10 Flow control; Congestion control

Abstract

A network device monitors the traffic of individual flows through one of its ingress ports and, if the traffic volume exceeds a predetermined threshold, signals for a reduction in data traffic volume transmitted to that ingress port from one or more source devices. Example signals may include without limitation a unicast congestion message sent to the source of a flow, an Explicit Congestion Notification to one or more source devices, and the dropping of packets by the receiving device. In response to such signals, one or more of the source devices decrease the transmission rate of data traffic to the receiving device.

Claims

1. A network device comprising:

a controller configured to detect data traffic received at an ingress port of the controller exceeding a pre-specified rate threshold, wherein the pre-specified rate threshold is less than a data traffic capacity of the controller and the controller is further configured to relay a signal to a source of the data flow to reduce its data output to a destination of the data flow, responsive to detecting the data traffic received at the ingress port of the controller exceeding the pre-specified rate threshold.

2. The network device of claim 1, wherein the data traffic is in a data flow from the source to the destination.

3. The network device of claim 2, wherein the pre-specified rate threshold applies to the data flow.

4. The network device of claim 2, wherein relaying the signal to the source of the data flow to reduce its data output to the destination of the data flow is further responsive to detecting the data traffic in the data flow received at the ingress port of the controller exceeding the pre-specified rate threshold.

5. The network device of claim 1, wherein the controller is further configured to monitor a quantity of the data traffic passing through the ingress port over a period of time to determine a data flow rate and compare the data flow rate with the pre-specified rate threshold.

6. The network device of claim 1, wherein the pre-specified rate threshold corresponds to a maximum data processing capability of the network device.

7. The network device of claim 1, wherein the pre-specified rate threshold corresponds to a service level agreement applying to the network device.

8. The network device of claim 1, wherein the controller is further configured to originate the signal to the source to reduce its data traffic output to the ingress port.

9. The network device of claim 8, wherein the signal includes one or both of a unicast congestion message and dropping packets of the data traffic at the ingress port of the controller.

10. The network device of claim 1, further comprising:

a virtual machine configured to originate the signal to the source to reduce its data traffic output to the ingress port.

11. The network device of claim 10, wherein the signal includes an explicit congestion notification.

12. The network device of claim 1, further comprising:

a virtual machine, wherein the data traffic is directed to the virtual machine.

13. The network device of claim 12, wherein the pre-specified rate threshold is specific to data traffic directed to the virtual machine.

14. The network device of claim 1, wherein the network device is a server and the controller is a network interface controller of the server.

15. One or more processor-readable storage media encoding processor-executable instructions for executing in a processor a computer process comprising:

detecting data traffic received at an ingress port of a controller exceeding a pre-specified rate threshold, wherein the pre-specified rate threshold is less than a data traffic capacity of the controller; and

signaling a source of the data flow to reduce its data output to a destination of the data flow, responsive to the detecting operation.

16. The one or more processor-readable storage media of claim 15, wherein the data traffic is in a data flow from the source to the destination.

17. The one or more processor-readable storage media of claim 16, wherein the pre-specified rate threshold applies to the data flow.

18. The one or more processor-readable storage media of claim 16, wherein the signaling operation is further responsive to detecting the data traffic in the data flow received at the ingress port of the controller exceeding the pre-specified rate threshold.

19. The one or more processor-readable storage media of claim 15, wherein the detecting operation includes monitoring a quantity of the data traffic passing through the ingress port over a period of time to determine a data flow rate and wherein the computer process further comprises:

comparing the data flow rate with the pre-specified rate threshold.

20. A method comprising:

detecting data traffic received at an ingress port of a controller exceeding a pre-specified rate threshold, wherein the pre-specified rate threshold is less than a data traffic capacity of the controller; and

signaling a source of the data flow to reduce its data output to a destination of the data flow, responsive to the detecting operation.