End-to end lossless Ethernet in Ethernet fabric

• US 9,736,085 B2
• Filed: 08/29/2012
• Issued: 08/15/2017
• Est. Priority Date: 08/29/2011
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, Inc. (Broadcom, Inc.)
• Inventors: Gupta, Rajnish, Raman, Mythilikanth, Song, Huan, Koganti, Phanidhar
• Primary Examiner(s): Yeung, Mang
• Assistant Examiner(s): Pascual Peguero, Natali N
• Application Number:
  US13/598,204
• Publication Number:
  US 20130051235A1
• Time in Patent Office: 1,812 Days
• Field of Search: 370218, 370235, 370392
• CPC Class Codes: H04L 47/2408 for supporting different services, e.g. a differentiated services [DiffServ] type of service
• CPC Class Codes: H04L 47/6215 Individual queue per QOS, rate or priority
• CPC Class Codes: H04L 49/205 Quality of Service based
• CPC Class Codes: H04L 49/253 using establishment or release of connections between ports
• CPC Class Codes: H04L 49/351 for local area network [LAN], e.g. Ethernet switches
• CPC Class Codes: H04L 49/505 Corrective measures

Abstract

One embodiment of the present invention provides a computing system. The computing system includes a packet processor, a buffer management module, a data monitoring module, and a flow control module. The packet processor identifies a class of service indicating priority-based flow control associated with a remote computing system from a notification message. The buffer management module creates a buffer dedicated for frames belonging to the class of service from the remote computing system in response to identifying the class of service. The data monitoring module detects a potential overflow of the buffer. The flow control module operates in conjunction with the packet processor to generate a pause frame in response to detecting a potential overflow.

Claims

1. A switch, comprising:

one or more ports;

a memory;

packet processing circuitry configured to identify a priority value in a first inner layer-2 header of a packet encapsulated with a first outer encapsulation header, wherein the priority value indicates a class of service associated with priority-based flow control for the packet, and wherein the first outer encapsulation header comprises a first switch identifier identifying the switch and a second switch identifier identifying a second switch in a routed network; and

flow control circuitry configured to, in response to detecting a potential buffer overflow for the class of service, generate a pause frame comprising a second inner layer-2 header for the class of service associated with the priority-based flow control, wherein the second inner layer-2 header is encapsulated with a second outer encapsulation header comprising the second switch identifier as a destination identifier, and wherein the first and second outer encapsulation headers are based on a same encapsulation protocol.

2. The switch of claim 1, wherein the potential buffer overflow is for a buffer configured to store the packet in response to the packet processor identifying the priority value indicating the class of service in the first inner layer-2 header of the packet.

3. The switch of claim 1, wherein the pause frame includes the priority value indicating the class of service.

4. The switch of claim 1, wherein the first inner layer-2 header is an Ethernet header and the first outer encapsulation header is forwardable in the routed network.

5. The switch of claim 1, wherein the first switch identifier is a virtual switch identifier associated with a virtual switch.

6. The switch of claim 1, wherein the switch is in a plurality of switches participating in a link aggregation, wherein the link aggregation includes a plurality of physical links operating as a single aggregated link, and wherein the plurality of switches are associated with a same media access control (MAC) address.

7. A switch, comprising:

identification circuitry configured to identify a class of service associated with priority-based flow control configured for the switch;

packet processing circuitry configured to identify a priority value in a first inner layer-2 header of a packet encapsulated with a first outer encapsulation header, wherein the priority value indicates the class of service associated with the priority-based flow control for the packet, and wherein the first outer encapsulation header comprises a first switch identifier identifying the switch in a routed network; and

notification circuitry configured to generate a notification message comprising a second inner layer-2 header in response to identifying the class of service, wherein the second inner layer-2 header is encapsulated with a second outer encapsulation header comprising a second switch identifier identifying a second switch in the routed network, and wherein the notification message specifies the class of service associated with the priority-based flow control configured for the switch.

8. The switch of claim 7, wherein the first inner layer-2 header is an Ethernet header and the first outer encapsulation header is forwardable in the routed network.

9. The switch of claim 7, wherein the switch is in a plurality of switches participating in a link aggregation, wherein the link aggregation includes a plurality of physical links operating as a single aggregated link, and wherein the plurality of switches are associated with a same media access control (MAC) address.

10. A method, comprising:

identifying, by a switch, a priority value in a first inner layer-2 header of a packet encapsulated with a first outer encapsulation header, wherein the priority value indicates a class of service associated with priority-based flow control for the packet, and wherein the first outer encapsulation header comprises a first switch identifier identifying the switch and a second switch identifier identifying a second switch in a routed network; and

in response to detecting a potential buffer overflow for the class of service, generating a pause frame comprising a second inner layer-2 header for the class of service associated with the priority-based flow control, wherein the second inner layer-2 header is encapsulated with a second outer encapsulation header comprising the second switch identifier as a destination identifier, and wherein the first and second outer encapsulation headers are based on a same encapsulation protocol.

11. The method of claim 10, wherein the potential buffer overflow is for a buffer configured to store the packet in response to identifying the priority value indicating the class of service in the first inner layer-2 header of the packet.

12. The method of claim 10, wherein the pause frame includes the priority value indicating the class of service.

13. The method of claim 10, wherein the first inner layer-2 header is an Ethernet header and the first outer encapsulation header is forwardable in the routed network.

14. The method of claim 10, wherein the first switch identifier is a virtual switch identifier associated with a virtual switch.

15. The method of claim 10, wherein the switch is in a plurality of switches participating in a link aggregation, wherein the link aggregation includes a plurality of physical links operating as a single aggregated link, and wherein the plurality of switches are associated with a same media access control (MAC) address.

16. A method, comprising:

identifying, by a switch, a class of service associated with priority-based flow control configured for the switch;

identifying a priority value in a first inner layer-2 header of a packet encapsulated with a first outer encapsulation header, wherein the priority value indicates the class of service associated with the priority-based flow control for the packet, and wherein the first outer encapsulation header comprises a first switch identifier identifying the switch in a routed network; and

generating a notification message comprising a second inner layer-2 header in response to identifying the class of service, wherein the second inner layer-2 header is encapsulated with a second outer encapsulation header comprising a second switch identifier identifying a second switch in the routed network, and wherein the notification message specifies the class of service associated with the priority-based flow control configured for the switch;

wherein the switch and the remote switch are member switches of the network of interconnected switches.

17. The method of claim 16, wherein the first inner layer-2 header is an Ethernet header and the first outer encapsulation header is forwardable in the routed network.

18. The method of claim 16, wherein the switch is in a plurality of switches participating in a link aggregation, wherein the link aggregation includes a plurality of physical links operating as a single aggregated link, and wherein the plurality of switches are associated with a same media access control (MAC) address.

19. A computer system, comprising:

processing circuitry; and

a non-transitory computer-readable storage medium storing instructions which when executed by the processing circuitry cause the processing circuitry to perform a method, the method comprising;

identifying a priority value in a first inner layer-2 header of a packet encapsulated with a first outer encapsulation header, wherein the priority value indicates a class of service associated with priority-based flow control for the packet, and wherein the first outer encapsulation header comprises a first identifier identifying the computer system and a second identifier identifying a second computer system in a routed network; and

in response to detecting a potential buffer overflow for the class of service, generating a pause frame comprising a second inner layer-2 header for the class of service associated with the priority-based flow control, wherein the second inner layer-2 header is encapsulated with a second outer encapsulation header comprising the second identifier as a destination identifier, and wherein the first and second outer encapsulation headers are based on a same encapsulation protocol.

20. A computer system, comprising:

processing circuitry; and

a non-transitory computer-readable storage medium storing instructions which when executed by the processing circuitry cause the processing circuitry to perform a method, the method comprising;

identifying a class of service associated with priority-based flow control configured for the computer system;

identifying a priority value in a first inner layer-2 header of a packet encapsulated with a first outer encapsulation header, wherein the priority value indicates the class of service associated with the priority-based flow control for the packet, and wherein the first outer encapsulation header comprises a first identifier identifying the computer system in a routed network; and

generating a notification message comprising a second inner layer-2 header in response to identifying the class of service, wherein the second inner layer-2 header is encapsulated with a second outer encapsulation header comprising a second identifier identifying a second computer system in the routed network, and wherein the notification message specifies the class of service associated with the priority-based flow control configured for the computer system.