FAST NETWORK FORMATION AFTER NETWORK POWER RESTORATION

• US 20160020997A1
• Filed: 12/19/2014
• Published: 01/21/2016
• Est. Priority Date: 07/21/2014
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Hui, Jonathan W., Hong, Wei, Vasseur, Jean-Philippe
• Granted Patent: US 9,641,382 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04L 41/06 Management of faults, events, alarms or notifications
• CPC Class Codes: H04L 41/0654 using network fault recovery ring fault isolation or reconfiguration in loop networks without recovery actions by a network management system H04L12/437
• CPC Class Codes: H04L 49/00 Packet switching elements
• CPC Class Codes: Y04S 40/00 Systems for electrical power generation, transmission, distribution or end-user application management characterised by the use of communication or information technologies, or communication or information technology specific aspects supporting them

Abstract

In one embodiment, a first device in a network detects a power restoration event subsequent to a power outage event. Power is restored to the first device during the power restoration event. The first device synchronizes a channel hopping schedule to the detected power restoration event. The first device communicates with a neighboring device of the first device using the channel hopping schedule synchronized to the detected power restoration event. The neighboring device uses a corresponding channel hopping schedule to communicate with the first device that is also synchronized to the power restoration event.

Claims

1. A method comprising:

detecting, by a first device in a network, a power restoration event subsequent to a power outage event, wherein power is restored to first device during the power restoration event;

synchronizing, by the first device, a channel hopping schedule of the first device to the detected power restoration event; and

communicating, by the first device, with a neighboring device of the first device using the channel hopping schedule synchronized to the detected power restoration event, wherein the neighboring device uses a corresponding channel hopping schedule to communicate with the first device that is also synchronized to the power restoration event.

2. The method as in claim 1, further comprising:

entering, by the first device, a power restoration mode, in response to detecting the power restoration event, wherein the first device communicates with the neighboring device in accordance with a power restoration mode communication policy while in the power restoration mode.

3. The method as in claim 2, wherein the power restoration mode communication policy corresponds to at least one of:

an increased dwell interval for the channel hopping schedule used by the first device to communicate with the neighboring device, an increased guard boundary for the channel hopping schedule used by the first device to communicate with the neighboring device, or using a wakeup sequence.

4. The method as in claim 2, further comprising:

exiting, by the device, the power restoration mode, in response to an amount of time after the power restoration event exceeding a threshold time limit.

5. The method as in claim 2, further comprising:

exiting, by the device, the power restoration mode, in response to receiving a multicast instruction message from a supervisory device.

6. The method as in claim 5, wherein the multicast instruction message indicates a time at which all receiving devices are to exit the power restoration mode.

7. The method as in claim 2, further comprising:

exiting, by the device, the power restoration mode at a different time than when one or more neighbors of the device exit the power restoration mode.

8. The method as in claim 7, wherein the device and the one or more neighbors of the device exit the power restoration mode at times based on their respective distances to a root node in the network.

9. The method as in claim 2, further comprising:

receiving, at the device, a new channel hopping schedule to communicate with the neighboring device, prior to exiting the power restoration mode.

10. The method as in claim 1, wherein the channel hopping schedule is stored in a persistent memory of the first device.

11. The method as in claim 1, further comprising:

sending, by the first device, a discovery message to reach one or more unsynchronized neighbors of the first device; and

determining, by the first device, a communication schedule to communicate with a particular unsynchronized neighbor.

12. The method as in claim 11, wherein the discovery message is sent in response to a determination that the first device is unable to communicate with the particular unsynchronized neighbor.

13. The method as in claim 12, wherein the particular unsynchronized neighbor is a parent of the first device in a routing topology used prior to the power outage event.

14. The method as in claim 11, wherein the first device sends the discovery message, in response to a determination that another node has not already sent a discovery message.

15. The method as in claim 14, wherein the first device waits a random amount of time prior to making the determination that another node has not already sent a discovery message.

16. The method as in claim 11, wherein the discovery message is a power restoration notification message.

17. An apparatus, comprising:

one or more network interfaces to communicate with a network;

a processor coupled to the one or more network interfaces and configured to execute a process; and

a memory configured to store the process executable by the processor, the process when executed operable to;

detect a power restoration event subsequent to a power outage event, wherein power is restored to the apparatus during the power restoration event;

synchronize a channel hopping schedule to the detected power restoration event; and

communicate with a neighboring device of the apparatus using the channel hopping schedule synchronized to the detected power restoration event, wherein the neighboring device uses a corresponding channel hopping schedule to communicate with the apparatus that is also synchronized to the power restoration event.

18. The apparatus as in claim 17, wherein the process when executed is further operable to:

enter a power restoration mode, in response to detecting the power restoration event, wherein the apparatus communicates with the neighboring device in accordance with a power restoration mode communication policy while in the power restoration mode.

19. The apparatus as in claim 17, wherein the process when executed is further operable to:

send a discovery message to reach one or more unsynchronized neighbors of the apparatus; and

determine a communication schedule to communicate with a particular unsynchronized neighbor.

20. A tangible, non-transitory, computer-readable media having software encoded thereon, the software when executed by a processor of a first device operable to:

detect a power restoration event subsequent to a power outage event, wherein power is restored to the first device during the power restoration event;

synchronize the channel hopping schedule to the detected power restoration event; and

communicate with a neighbor of the first device using the channel hopping schedule synchronized to the detected power restoration event, wherein the neighboring device uses a corresponding channel hopping schedule to communicate with the first device that is also synchronized to the power restoration event.

21. The computer-readable media as in claim 20, wherein the software when executed is further operable to:

enter a power restoration mode, in response to detecting the power restoration event, wherein the first device communicates with the neighbor in accordance with a power restoration mode communication policy while in the power restoration mode.

22. The computer-readable media as in claim 20, wherein the software when executed is further operable to:

send a discovery message to reach one or more unsynchronized neighbors of the first device; and

determine a communication schedule to communicate with a particular unsynchronized neighbor.