METHOD AND APPARATUS OF PERFORMING PROTECTION SWITCHING ON NETWORKS

• US 20130077479A1
• Filed: 09/24/2012
• Published: 03/28/2013
• Est. Priority Date: 09/22/2011
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: RYOO, Jeong-dong, CHEUNG, Taesik
• Granted Patent: US 8,929,201 B2
• Time in Patent Office: Days
• US Class Current: 370/225
• CPC Class Codes: H04L 1/22 using redundant apparatus to increase reliability
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 49/557 Error correction, e.g. fault recovery or fault tolerance
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

A protection switching unit and a method of performing protection switching of the protection switching unit are provided. The method includes steps of detecting a fault that has occurred at a working path of a network; opening a first switch that is connected to the working path and closing a second switch that is connected to the protection path of the network; and maintaining a connection state of the first switch and the working path and a connection state of the second switch and the protection path, when a fault that has occurred at the working path is restored.

Claims

1. A method of performing protection switching of one node of a plurality of nodes that are connected through a working path and a protection path, the method comprising:

opening, when a signal failure fault that has occurred at the working path is detected, a first switch that is connected to the working path and closing a second switch that is connected to the protection path; and

maintaining, when the node operates in a non-reverse mode, if the signal failure fault is restored, a state of the first switch and a state of the second switch.

2. The method of claim 1, further comprising closing, when a signal degrade fault that has occurred at the working path or the protection path is detected, the first switch and the second switch.

3. The method of claim 1, further comprising closing, after the maintaining of a state of the first switch and a state of the second switch, when a preset time has elapsed, the first switch and opening the second switch.

4. The method of claim 1, wherein the first switch is closed and the second switch is opened, before the signal failure fault occurs at the working path.

5. A protection switching unit that is included in one node of a plurality of nodes that are connected through a working path and a protection path, the protection switching unit comprising:

a path search unit that detects a path fault that has occurred at the working path and the protection path and restoration of the path fault;

a first switch that is connected to the working path;

a second switch that is connected to the protection path; and

a controller that transfers an open command to the first switch and that transfers a close command to the second switch, when the path search unit detects a signal failure fault that has occurred at the working path and that transfers a state maintenance command to the first switch and the second switch, when the bridge operates in a non-reverse mode, if the signal failure fault is restored.

6. The protection switching unit of claim 5, wherein the controller transfers a close command to the first switch and the second switch, when the path search unit detects a signal degrade fault that has occurred at the working path or the protection path.

7. The protection switching unit of claim 5, wherein the controller transfers a close command to the first switch and transfers an open command to the second switch, after the controller transfers a state maintenance command to the first switch and the second switch, when a preset time has elapsed.

8. The protection switching unit of claim 5, wherein the first switch is closed and the second switch is opened, before the signal failure fault occurs at the working path.