MAC address synchronization in a fabric switch

• US 9,413,691 B2
• Filed: 01/13/2014
• Issued: 08/09/2016
• Est. Priority Date: 01/11/2013
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, Inc. (Broadcom, Inc.)
• Inventors: Venkatesh, Vardarajan
• Primary Examiner(s): Haile, Awet
• Application Number:
  US14/154,106
• Publication Number:
  US 20140198801A1
• Time in Patent Office: 939 Days
• US Class Current: 1/1
• CPC Class Codes: H04L 49/10 characterised by the switching fabric construction
• CPC Class Codes: H04L 49/111 Switch interfaces, e.g. port details
• CPC Class Codes: H04L 49/118 Address processing within a device, e.g. using internal ID or tags for routing within a switch
• CPC Class Codes: H04L 7/0037 Delay of clock signal
• CPC Class Codes: H04L 7/0041 Delay of data signal
• CPC Class Codes: H04L 7/0337 Selecting between two or more discretely delayed clocks or selecting between two or more discretely delayed received code signals

Abstract

One embodiment of the present invention provides a system for facilitating synchronization of MAC addresses in a fabric switch. During operation, the system divides a number of media access control (MAC) addresses associated with devices coupled to an interface of the switch. The system then computes a checksum for a respective chunk of MAC addresses. In addition, the system broadcasts MAC address information of the chunk to facilitate MAC address synchronization in a fabric switch of which the switch is a member, and to manage the chunks and their corresponding checksum, thereby correcting an unsynchronized or race condition in the fabric switch.

Claims

1. A switch, comprising:

chunking circuitry configured to divide a number of media access control (MAC) addresses associated with devices coupled to an interface of the switch into a number of chunks, wherein a chunk includes a plurality of MAC addresses;

checksum circuitry configured to compute a checksum for a respective chunk of MAC addresses; and

MAC synchronization circuitry configured to;

construct a broadcast message comprising MAC address information of one or more chunks to facilitate MAC address synchronization in a network of interconnected switches, wherein the switch is a member of the network of interconnected switches;

manage the chunks and their corresponding checksums, thereby correcting an unsynchronized or race condition in the network of interconnected switches.

2. The switch of claim 1, wherein while managing the chunks and their corresponding checksums, the MAC synchronization circuitry is configured to refrain from constructing a notification message comprising an updated checksum of a chunk, which includes at least one MAC address that has been updated, in response to detecting an update to the corresponding chunk received from another switch.

3. The switch of claim 1, wherein the MAC synchronization circuitry is further configured to construct a notification message comprising a checksum of a respective chunk in response to detecting that a guard timer has been expired, wherein the notification message is destined to other switches in the network of interconnected switches.

4. The switch of claim 1, wherein the MAC synchronization circuitry is further configured to construct a notification message comprising content of a chunk in response to detecting an unsynchronized condition associated with the chunk received from a remote switch, wherein the notification message is destined to the remote switch, and wherein an update to the chunk has not been detected by the switch within a past predetermined time window.

5. The switch of claim 1, wherein the MAC synchronization circuitry is further configured to refrain from comparing a new checksum for a chunk received from an owner switch of the chunk, in response to detecting an update to the chunk received from another switch other than the owner switch within a past predetermined time window.

6. The switch of claim 1, wherein the checksum for a respective chunk is related to the content of that chunk but not related to the order of the MAC addresses in that chunk.

7. The switch of claim 1, wherein each chunk of MAC addresses associated with the interface includes MAC addresses with a same last n bits, wherein n is a predetermined number.

8. A method, comprising:

dividing a number of media access control (MAC) addresses associated with devices coupled to an interface of the switch, wherein a chunk includes a plurality of MAC addresses;

computing a checksum for a respective chunk of MAC addresses;

constructing a broadcast message comprising MAC address information of one or more chunks to facilitate MAC address synchronization in a network of interconnected switches, wherein the switch is a member of the network of interconnected switches; and

managing the chunks and their corresponding checksums, thereby correcting an unsynchronized or race condition in the network of interconnected switches.

9. The method of claim 8, wherein managing the chunks and their corresponding checksums comprises refraining from constructing a notification message comprising an updated checksum of a chunk, which includes at least one MAC address that has been updated, in response to detecting an update to the corresponding chunk received from another switch.

10. The method of claim 8, further comprising constructing a notification message comprising a checksum of a respective chunk in response to detecting that a guard timer has been expired, wherein the notification message is destined to other switches in the network of interconnected switches.

11. The method of claim 8, further comprising constructing a notification message comprising content of a chunk in response to detecting an unsynchronized condition associated with the chunk received from a remote switch, wherein the notification message is destined to the remote switch, and wherein an update to the chunk has not been detected by the switch within a past predetermined time window.

12. The method of claim 8, further comprising refraining from comparing a new checksum for a chunk received from an owner switch of the chunk, in response to detecting an update to the chunk received from another switch other than the owner switch within a past predetermined time window.

13. The method of claim 8, wherein the checksum for a respective chunk is related to the content of that chunk but not related to the order of the MAC addresses in that chunk.

14. The switch of claim 8, wherein each chunk of MAC addresses associated with the interface includes MAC addresses with a same last n bits, wherein n is a predetermined number.

15. A computing system for a switch, comprising:

a processor; and

a storage device storing instructions which when executed by the processor cause the processor to perform a method, the method comprising;

dividing a number of media access control (MAC) addresses associated with devices coupled to an interface of the switch, wherein a chunk includes a plurality of MAC addresses;

computing a checksum for a respective chunk of MAC addresses;

constructing a broadcast message comprising MAC address information of one or more chunks to facilitate MAC address synchronization in a network of interconnected switches, wherein the switch is a member of the network of interconnected switches; and

managing the chunks and their corresponding checksums, thereby correcting an unsynchronized or race condition in the network of interconnected switches.

16. The computing system of claim 15, wherein managing the chunks and their corresponding checksums comprises refraining from constructing a notification message comprising an updated checksum of a chunk, which includes at least one MAC address that has been updated, in response to detecting an update to the corresponding chunk received from another switch.

17. The computing system of claim 15, wherein the method further comprises constructing a notification message comprising a checksum of a respective chunk in response to detecting that a guard timer has expired, wherein the notification message is destined to other switches in the network of interconnected switches.

18. The computing system of claim 15, wherein the method further comprises constructing a notification message comprising content of a chunk to a remote switch in response to detecting an unsynchronized condition associated with the chunk received from a remote switch, wherein the notification message is destined to the remote switch, and wherein an update to the chunk has not been detected by the switch within a past predetermined time window.

19. The computing system of claim 15, wherein the method further comprises refraining from comparing a new checksum received for a chunk from an owner switch of the chunk in response to detecting an update to the chunk received from another switch other than the owner switch within a past predetermined time window.

20. The computing system of claim 15, wherein the checksum for a respective chunk is related to the content of that chunk but not related to the order of the MAC addresses in that chunk.

21. The computing system of claim 15, wherein each chunk of MAC addresses associated with the interface includes MAC addresses with a same last n bits, wherein n is a predetermined number.