Method of and control node for detecting failure

• US 20050122908A1
• Filed: 05/06/2004
• Published: 06/09/2005
• Est. Priority Date: 12/09/2003
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Kano, Shinya, Soumiya, Toshio
• Granted Patent: US 7,564,778 B2
• Time in Patent Office: Days
• US Class Current: 370/241
• CPC Class Codes: H04J 14/0227 Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
• CPC Class Codes: H04J 14/0241 Wavelength allocation for communications one-to-one, e.g. unicasting wavelengths
• CPC Class Codes: H04J 14/0284 WDM mesh architectures
• CPC Class Codes: H04L 41/0677 Localisation of faults
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0081 Fault tolerance; Redundancy; Recovery; Reconfigurability
• CPC Class Codes: H04Q 2011/0088 Signalling aspects

Abstract

A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, includes the steps of transmitting, from a control node connected to a communication node having detected a failure to an adjacent control node, a failure information message having a time indication indicative of a time at which the failure is detected, and identifying, at a given control node which received the failure information message, a location of the failure in response to the time indication.

Claims

1. A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said method comprising the steps of:

transmitting, from a control node connected to a communication node having detected a failure to an adjacent control node, a failure information message having a time indication indicative of a time at which the failure is detected; and

identifying, at a given control node which received the failure information message, a location of the failure in response to the time indication.

2. A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said method comprising the steps of:

transmitting a failure information message from a control node connected to a communication node having detected a failure to a control node that is situated downstream on a path along which the failure is detected; and

identifying a given control node as a location of the failure if the given control node has transmitted the failure information message and has not received the failure information message from upstream on said path.

6. The method as claimed in claim 2, wherein said step of transmitting a failure information message includes activating a timer at a same timing as the failure information message is transmitted, and said step of identifying a given control node identifies the given control node as a location of the failure if the given control node has transmitted the failure information message and has not received the failure information message from upstream on said path within a time period specified by the timer.

7. The method as claimed in claim 6, wherein the time period specified by the timer is longer than a sum of an information delay between adjacent control nodes and a processing time at a control node.

3. A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said method comprising the steps of:

transmitting a failure information message from a control node connected to a communication node having detected a failure to a control node that is situated upstream on a path along which the failure is detected; and

identifying a given control node as a location of the failure if the failure information message has been transmitted to the given control node and no response thereto has been received from the given control node.

4. A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said method comprising the steps of:

transmitting a failure information message from a control node connected to a communication node having detected a failure to a control node that is situated upstream on a path along which the failure is detected;

checking, at a control node having received the failure information message, whether a communication node connected thereto suffers a failure, and transmitting a result of the checking to a control node from which the failure information message is received; and

identifying the failure based on the result of the checking.

5. A control node for detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said control node comprising:

a failure information message transmitting unit which generates a failure information message having a time indication indicative of a time at which a failure is detected in response to a notice supplied from a communication node connected to said control node, and transmits the failure information message to an adjacent control node; and

a failure-point identifying unit which identifies a location of the failure by identifying a failure information message having a time indication indicative of an earliest time amongst failure information messages received from other control nodes.

8. A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said method comprising the steps of:

transmitting a failure information message from a control node connected to a communication node having detected a failure to a control node that is situated upstream on a path along which the failure is detected; and

identifying a given control node as a location of the failure if the given control node receives a response indicative of no failure detection from an upstream control node to which the given control node has transmitted the failure information message.

9. A method of detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said method comprising the steps of:

performing, from a control node connected to a communication node having detected a failure, flooding of a failure information message having a time indication indicative of a time at which the failure is detected; and

identifying, at a given control node which received one or more failure information messages, a location of the failure by identifying a failure information message having a time indication indicative of an earliest time amongst said one or more failure information messages.

10. A control node for detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said control node comprising:

a failure information message transmitting unit which generates a failure information message in response to a notice of detection of a failure supplied from a communication node connected to said control node, and transmits the failure information message downstream on a path along which the failure is detected; and

a failure-point identifying unit which identifies said control node as a location of the failure if the failure information message is not received from upstream on the path.

13. The control node as claimed in claim 10, further comprising a timer which is activated in response to receipt of the failure information message, wherein said failure-point identifying unit identifies said control node as a location of the failure if the failure information message is not received from upstream on the path within a time period specified by said timer.

14. The control node as claimed in claim 13, wherein the time period specified by the timer is longer than a sum of an information delay between adjacent control nodes and a processing time at a control node.

11. A control node for detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said control node comprising:

a failure information message transmitting unit which generates a failure information message in response to a notice of detection of a failure supplied from a communication node connected to said control node, and transmits the failure information message to a control node provided upstream on a path along which the failure is detected; and

a failure-point identifying unit which identifies the upstream control node as a location of the failure if the upstream control node does not return a response to the failure information message.

12. A control node for detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said control node comprising:

a failure information message transmitting unit which generates a failure information message in response to a notice of detection of a failure supplied from a communication node connected to said control node, and transmits the failure information message upstream on a path along which the failure is detected; and

a failure-point identifying unit which identifies a location of the failure by checking in response to receipt of the failure information message whether the communication node connected to said control node suffers a failure and by transmitting a result of the checking to a control node from which the failure information message is received.

15. A control node for detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said control node comprising:

a failure information message transmitting unit which generates a failure information message in response to a notice of detection of a failure supplied from a communication node connected to said control node, and transmits the failure information message upstream on a path along which the failure is detected; and

a failure-point identifying unit which identifies said control node as a location of the failure if said control node receives a response indicative of no failure detection from an upstream control node to which said control node has transmitted the failure information message.

16. A control node for detecting a failure in a network, which includes a transport plane comprised of a plurality of communication nodes performing optical cross-connect and a control plane comprised of a plurality of control nodes that are connected to and control the respective communication nodes, said control node comprising:

a failure information message flooding unit which generates a failure information message in response to a notice of detection of a failure supplied from a communication node connected to said control node, and performs flooding of the failure information message; and

a failure-point identifying unit which identifies a location of the failure by identifying a failure information message having a time indication indicative of an earliest time amongst one or more received failure information messages.