Dynamic spanning tree root selection

Patent metadata

Field	Value
Publication number	US-9306764-B2
Application number	US-201213538675-A
Country	US
Kind code	B2
Filing date	Jun 29, 2012
Priority date	Jun 29, 2012
Publication date	Apr 5, 2016
Grant date	Apr 5, 2016

Abstract

Systems, methods, apparatus, and articles of manufacture to provide root re-selection in a spanning tree protocol are disclosed. An example method includes transmitting, from a current root device on a playback network, a query message to a router on the playback network. The example method includes evaluating a response received from at least one intermediate device between the current root and the router, the at least one intermediate device relaying the query message from the root to the router and transmitting a response back to the current root device indicating a root path cost associated with that intermediate device. The example method includes determining, based on the received root path cost(s), an updated designation of a new root device for the playback network. The example method includes, if the new root device is different from the current root device, exchanging bridge priority between the current root and the new root.

First claim

We claim:

1. A method comprising:
periodically transmitting, from a playback device designated as a current root device on a playback network, a first query message to a router via a first intermediate device on the playback network and a second query message to the router via a second intermediate device on the playback network, the playback network organized according to a spanning tree protocol;
evaluating, at the current root device, a first response received from the first intermediate device and a second response received from the second intermediate device, the first and the second intermediate devices relaying the first and the second query messages, respectively, from the current root device to the router, wherein the first response indicates a first root path cost and the second response indicates a second root path cost associated with relaying of the respective first and second query messages from the current root device to the router via the first and the second intermediate devices;
determining, at the current root device, based on a comparison of the first and the second root path costs, an updated designation of a new root device for the playback network; and
if the new root device is different from the current root device, exchanging, via the current root device, bridge priority between the current root device and the new root device.

2. The method of claim 1 , further including triggering root re-selection upon a change in a topology of the playback network.

3. The method of claim 1 , further including triggering root re-selection upon power-up of the current root device.

4. The method of claim 1 , wherein evaluating the first response from the first intermediate device and the second response from the second intermediate device and determining the updated designation includes comparing the first and the second root path costs to select the intermediate device associated with a highest value root path cost as the new root device.

5. The method of claim 1 , wherein, if no responses are received, the current root device remains the current root device for the playback network.

6. The method of claim 1 , further including setting, at the current root device, a timer within which to receive a response.

7. The method of claim 1 , further including propagating, via the current root device, a topology change notification to devices on the playback network.

8. A non-transitory computer readable storage medium including instructions for execution by a processor, the instructions, when executed by the processor, to implement a method of spanning tree root re-selection in a playback network, the method comprising:
periodically transmitting, from a playback device designated as a current root device on a playback network, a first query message to a router via a first intermediate device on the playback network and a second query message to the router via a second intermediate device on the playback network, the playback network organized according to a spanning tree protocol;
evaluating, at the current root device, a first response received from the first intermediate device and a second response received from the second intermediate device, the first and the second intermediate devices relaying the first and the second query messages, respectively, from the current root device to the router, wherein the first response indicates a first root path cost and the second response indicates a second root path cost associated with relaying of the respective first and second query messages from the current root device to the router via the first and the second intermediate devices;
determining, at the current root device, based on a comparison of the first and the second root path cost response, an updated designation of a new root device for the playback network; and
if the new root device is different from the current root device, exchanging, via the current root device, bridge priority between the current root device and the new root device.

9. The non-transitory computer-readable storage medium of claim 8 , wherein the method further includes triggering root re-selection upon a change in a topology of the playback network.

10. The non-transitory computer-readable storage medium of claim 8 , wherein the method further includes triggering root re-selection upon power-up of the current root device.

11. The non-transitory computer-readable storage medium of claim 8 , wherein evaluating the first response from the first intermediate device and the second response from the second intermediate device and determining the updated designation includes comparing the first and the second root path costs to select the intermediate device associated with a highest value root path cost as the new root device.

12. The non-transitory computer-readable storage medium of claim 8 , wherein, if no responses are received, the current root device remains the current root device for the playback network.

13. The non-transitory computer-readable storage medium of claim 8 , wherein the method further includes setting, at the current root device, a timer within which to receive a response.

14. A media playback device comprising:
a communication interface to send and receive data via a network connection, the data including multimedia content for playback;
a memory to store instructions and data including a designation of the media playback device as root for a local playback network; and
a processor to:
periodically transmit a first query message to a router via a first intermediate device on the local playback network and a second query message to the router via a second intermediate device on the playback network, the local playback network organized according to a spanning tree protocol;
evaluate a first response received from the first intermediate device and a second response received from the second intermediate device, the first and the second intermediate devices to relay the first and the second query messages, respectively, from the root to the router, wherein the first response indicates a first root path cost and the second response indicates a second root path cost associated with relaying of the respective first and second query messages from the root device to the router via the first and the second intermediate devices;

determine, based on a comparison of the first and the second root path costs, an updated root designation for the local playback network; and
if the updated root designation is different from the root, exchanging bridge priority between the media playback device and the intermediate device associated with the updated root designation.

15. The media playback device of claim 14 , wherein the processor is to trigger root re-selection upon a change in a topology of the local playback network.

16. The media playback device of claim 14 , wherein the processor is to trigger root re-selection upon power-up of the media playback device.

17. The media playback device of claim 14 , wherein evaluating the first response from the first intermediate device and the second response from the second intermediate device and determining the updated root designation includes comparing the first and the second root path costs to select the intermediate device associated with a highest value root path cost as a new root.

18. The media playback device of claim 14 , wherein, if no responses are received, the media playback device remains the root for the local playback network.

19. The media playback device of claim 14 , wherein the processor is to s

Assignees

• Gossain Hrishikesh
• Millington Nicholas A J
• Peters Jeffrey M
• Sonos Inc

Inventors

• Gossain Hrishikesh
• Millington Nicholas A J
• Peters Jeffrey M

Classifications

• H04L12/2838 Primary

  Distribution of signals within a home automation network, e.g. involving splitting/multiplexing signals to/from different paths (adaptations of television systems for transmission by electric cable for domestic distribution H04N7/106; hybrid transport H04L12/6418; home network arrangements specially adapted for distribution of digital video signals H04N7/24) · CPC title

• H04L12/462

  LAN interconnection over a bridge based backbone · CPC title

• H04L45/02

  Topology update or discovery · CPC title

• H04L45/48

  Routing tree calculation · CPC title

• H04L45/488

  using root node determination · CPC title