Method for selecting root bridge in configuration of spanning tree

• US 20070206513A1
• Filed: 12/20/2006
• Published: 09/06/2007
• Est. Priority Date: 03/03/2006
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Hwang, Seong-Taek, Kim, Hoon, Cho, Jae-Hun, Yoon, Jong-Ho, Wang, Sihai
• Application Number:
  US11/642,572
• Publication Number:
  US 20070206513A1
• Time in Patent Office: Days
• US Class Current: 370/254
• CPC Class Codes: H04L 12/4625 Single bridge functionality, e.g. connection of two networks over a single bridge

Abstract

Disclosed is a method, apparatus and computer-readable medium for selecting a root bridge when a spanning tree is configured in an Ethernet network including a plurality of legacy switches and a plurality of synchronous switches. The method comprises the steps of providing in advance identification information in a configuration BPDU message of the synchronous switch, the identification information representing that a corresponding switch is an AV switch, broadcasting configuration BPDU messages by the legacy switches and the synchronous switches; and receiving configuration BPDU messages by the synchronous switch from other switches, confirming bridge priorities according to the synchronous switches through the received configuration BPDU message and the identification information to select a synchronous root bridge, receiving configuration BPDU messages by the legacy switch from other switches, and confirming bridge priorities through the received configuration BPDU messages to select a legacy root bridge.

Claims

1. A method for selecting a root bridge when a spanning tree is configured in an Ethernet network including a plurality of legacy switches and a plurality of synchronous switches, the method comprising the steps of:

providing identification information in a configuration Bridge Protocol Data Unit (BPDU) message of the synchronous switch, the identification information representing that a corresponding switch is an AV switch;

broadcasting configuration BPDU messages by the legacy switches and the synchronous switches; and

receiving configuration BPDU messages by the synchronous switch from other switches, confirming bridge priorities according to the synchronous switches through the received configuration BPDU message and the identification information to select a synchronous root bridge, receiving configuration BPDU messages by the legacy switch from other switches, and confirming bridge priorities through the received configuration BPDU messages to select a legacy root bridge.

2. The method as claimed in claim 1, wherein, in the identification information, a root ID has a preset value.

3. The method as claimed in claim 2, wherein the identification information has a value at least higher than 0X8000.

4. The method as claimed in claim 1, wherein the step of selecting the synchronous root bridge comprises the steps of:

when a priority of the synchronous switch is lower than priorities of the received configuration BPDU message, updating information of a network by the synchronous switch according to the corresponding received configuration BPDU messages, and stopping broadcasting its own configuration BPDU message; and

when the priority of the synchronous switch is higher than priorities of the received configuration BPDU messages, dropping by the synchronous switch the received configuration BPDU messages.

5. The method as claimed in claim 1, wherein the step of selecting the legacy root bridge comprises the steps of:

when a priority of the legacy switch is lower than priorities of the received configuration BPDU message, updating information of a network by the legacy switch according to the corresponding received configuration BPDU messages, and stopping broadcasting its own configuration BPDU message; and

when the priority of the synchronous switch is higher than priorities of the received configuration BPDU messages, dropping by the legacy switch the received configuration BPDU messages.

6. The method as claimed in claim 1, wherein the priority is determined in a sequence of a lowest root ID, a lowest root path cost, a lowest bridge ID and a lowest port ID.

7. At method for selecting a root bridge in a synchronous switch when a spanning tree is configured in an Ethernet network including a plurality of legacy switches and a plurality of synchronous switches, the method comprising the steps of:

broadcasting, in advance, a configuration Bridge Protocol Data Unit (BPDU) frame including identification information at a preset hello time, the identification information representing that a corresponding switch is a synchronous switch;

when configuration BPDU frames are received from other switches, determining if the identification information is confirmed from the received configuration BPDU frames;

comparing a priority of the received configuration BPDU information with a priority of BPDU information of the synchronous switch;

when the received configuration BPDU information has a higher priority, stopping broadcasting the configuration BPDU frame, and updating information of a network according to the received configuration BPDU information; and

when the received configuration BPDU information has a lower priority, dropping corresponding received configuration BPDU frames.

8. The method as claimed in claim 7, further comprising a step of continuing to receive the configuration BPDU frames from other switches even after stopping broadcasting the configuration BPDU frame, and continuing to update information of the network according to the received configuration BPDU frames.

9. The method as claimed in claim 7, wherein, in the identification information, a root ID has a preset value.

10. The method as claimed in claim 7, wherein the identification information has a value at least higher than 0X8000.

11. The method as claimed in claim 8, wherein the priority is determined in a sequence of a lowest root ID, a lowest root path cost, a lowest bridge ID and a lowest port ID.

12. An apparatus for selecting a root bridge when a spanning tree is configured in an Ethernet network including a plurality of legacy switches and a plurality of synchronous switches, the apparatus comprising:

a processor in communication with a memory, the processor executing computer code instructing the processor to execute the steps of;

providing identification information in a configuration Bridge Protocol Data Unit (BPDU) message of the synchronous switch, the identification information representing that a corresponding switch is an AV switch;

broadcasting configuration BPDU messages by the legacy switches and the synchronous switches; and

receiving configuration BPDU messages by the synchronous switch from other switches, confirming bridge priorities according to the synchronous switches through the received configuration BPDU message and the identification information to select a synchronous root bridge, receiving configuration BPDU messages by the legacy switch from other switches, and confirming bridge priorities through the received configuration BPDU messages to select a legacy root bridge.

13. The apparatus as claimed in claim 12, wherein, in the identification information, a root ID has a preset value.

14. The apparatus as claimed in claim 13, wherein the identification information has a value at least higher than 0X8000.

15. The apparatus as claimed in claim 12, wherein the step of selecting the synchronous root bridge comprises the steps of:

when a priority of the synchronous switch is lower than priorities of the received configuration BPDU message, updating information of a network by the synchronous switch according to the corresponding received configuration BPDU messages, and stopping broadcasting its own configuration BPDU message; and

when the priority of the synchronous switch is higher than priorities of the received configuration BPDU messages, dropping by the synchronous switch the received configuration BPDU messages.

16. The apparatus as claimed in claim 12, wherein the step of selecting the legacy root bridge comprises the steps of:

when a priority of the legacy switch is lower than priorities of the received configuration BPDU message, updating information of a network by the legacy switch according to the corresponding received configuration BPDU messages, and stopping broadcasting its own configuration BPDU message; and

when the priority of the synchronous switch is higher than priorities of the received configuration BPDU messages, dropping by the legacy switch the received configuration BPDU messages.

17. The apparatus as claimed in claim 12, wherein the priority is determined in a sequence of a lowest root ID, a lowest root path cost, a lowest bridge ID and a lowest port ID.

18. The apparatus as claimed in claim 12, further comprising:

an input/output device in communication with the processor.

19. The apparatus as claimed in claim 12, wherein the computer code is stored in the memory.