Fault propagation in segmented protection

Patent metadata

Field	Value
Publication number	US-10601537-B2
Application number	US-201816100230-A
Country	US
Kind code	B2
Filing date	Aug 10, 2018
Priority date	Feb 12, 2016
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

The disclosure provides an interconnecting node for interconnecting first and second protected domains, the second protected domain comprising a working path and a protection path for linear protection in a network for traffic forwarding between two end-nodes. The interconnecting node comprises at least one interface for receiving first monitoring information from the first protected domain, a monitoring unit for detecting an isolation condition of the interconnecting node within the first protected domain based on the first monitoring information, and generating second monitoring information to be transmitted to the working path so that a failure in the working path is detectable based on the second monitoring information at a far-end node of the working path. If an isolation condition is detected, the monitoring unit starts transmitting alarm indication information to the working path for suppressing at the far-end node an alarm reporting regarding a failure in the working path.

First claim

What is claimed is:

1. Interconnecting node for interconnecting a first protected domain and a second protected domain, the second protected domain comprising a working path and a protection path for linear protection in a network for traffic forwarding between two end-nodes, wherein the first or second protected domain represents a protected portion of an end-to-end connection, and wherein the interconnecting node comprises a processor and a memory, the memory is configured to store a program, and the processor invokes the program in the memory and is configured to:
receive a first monitoring information from the first protected domain, and
detect an isolation condition of the interconnecting node within the first protected domain based on the first monitoring information, and generate a second monitoring information, and
transmit the second monitoring information over the working path of the second protected domain so that a failure in the working path is detectable based on the second monitoring information at a far-end node of the working path, and
start a transmission of alarm indication information (AIS) over the working path of the second protected domain for suppressing at the far-end node an alarm reporting regarding a failure in the working path of the second protected domain, when the isolation condition of the interconnecting node within the first protected domain is detected.

2. The interconnecting node according to claim 1 , wherein the processor is further configured to:
prevent the transmission of the second monitoring information to the working path of the second protected domain when the isolation condition of the interconnecting node within the first protected domain is detected.

3. The interconnecting node according to claim 1 ,
wherein, the first protected domain comprises a given working path and a given protection path for linear protection; and
the processor is configured to:
detect that the interconnecting node is isolated within the first protected domain if a failure in the given working path and a failure of a vertical path are detected, the vertical path connecting the interconnecting node with a second interconnecting node in the first protected domain.

4. The interconnecting node according to claim 2 ,
wherein, the first protected domain comprises a given working path and a given protection path for linear protection; and
the processor is configured to:
detect that the interconnecting node is isolated within the first protected domain if a failure in the given working path and a failure of a vertical path are detected, the vertical path connecting the interconnecting node with a second interconnecting node in the first protected domain.

5. The interconnecting node according to claim 1 ,
wherein the far-end node of the second working path is one of the two end-nodes.

6. The interconnecting node according to claim 1 ,
wherein, the processor is further configured to:
when an isolation condition of the interconnecting node within the first protected domain is detected,
generate and start a transmission of modified second monitoring information to the working path of the second protected domain, said modified second monitoring information indicating that a detected failure on the working path is caused by fault propagation of a failure in the first protected domain.

7. The interconnecting node according to claim 2 ,
wherein, the processor is further configured to:
when an isolation condition of the interconnecting node within the first protected domain is detected,
generate and start a transmission of modified second monitoring information to the working path of the second protected domain, said modified second monitoring information indicating that a detected failure on the working path is caused by fault propagation of a failure in the first protected domain.

8. The interconnecting node according to claim 6 ,
wherein, the processor is further configured to:
when the isolation condition of the interconnecting node within the first protected domain is detected,
concurrently start the transmission of the modified second monitoring information to the working path of the second protected domain, and start the transmission of AIS to the working path of the second protected domain.

9. The interconnecting node according to claim 1 ,
wherein the far-end node of the second working path is connected to a further protected domain used for traffic forwarding between the two end-nodes.

10. The interconnecting node according to claim 6 ,
wherein the processor is further configured to:
receive modified first monitoring information from the first protected domain, and
distinguish between a reception of the first monitoring information and of the modified first monitoring information, and
detect that a failure is located in a further working path interconnected with the first protected domain, when the modified first monitoring information is received.

11. The interconnecting node according to claim 1 ,
wherein the network is a packet network, preferably an Ethernet network or a network based on Multi-Protocol Label Switching Transport Profile (MPLS-TP),
the first monitoring information and second monitoring information is respectively transmitted by means of Continuity Check Message (CCM) Operations, Administration and Maintenance (OAM) packets, and
the alarm indication information, is transmitted as an Alarm Indication Signal (AIS) OAM packet.

12. The interconnecting node according to claim 2 ,
wherein the network is a packet network, preferably an Ethernet network or a network based on Multi-Protocol Label Switching Transport Profile (MPLS-TP)
the first monitoring information and second monitoring information are respectively transmitted by means of Continuity Check Message (CCM) Operations, Administration and Maintenance (OAM) packets, and
the alarm indication information, is transmitted as an Alarm Indication Signal (AIS) OAM packet.

13. The interconnecting node according to claim 1 ,
wherein the network is a Time-Division Multiplexing (TDM) network, preferably Optical Transport Network (OTN) or Synchronous Digital Hierarchy (SDH) and
the first monitoring information, the second monitoring information and the alarm indication information are respectively transmitted by means of specific bytes in an overhead of a TDM frame.

14. The interconnecting node according to claim 2 ,
wherein the network is a Time-Division Multiplexing (TDM) network, preferably Optical Transport Network (OTN) or Synchronous Digital Hierarchy (SDH) and
the first monitoring information, the second monitoring information and the alarm indication information are respectively transmitted by means of specific bytes in an overhead of a TDM frame.

15. Method for interconnecting via an interconnecting node, a first protected domain and a second protected domain, the first or second protected domain representing a protected portion of an end-to-end connection, and the second protected domain comprising a working path and a protection path for linear protection in a network for traffic forwarding between two end-nodes, wherein the method comprises:
receiving a first monitoring information from the first protected domain; and
detecting an isolation condition of the interconnecting node within the first protected domain based on the first monitoring information, and generating a second monitoring information, wherein
transmitting the second monitoring information to the working path of the second protected domain, so that a failure in the working path is detectable based on the seco

Assignees

• Huawei Tech Co Ltd

Inventors

• Busi Italo
• Ye Min

Classifications

• H04L45/28

  using route fault recovery · CPC title

• H04L45/50

  using label swapping, e.g. multi-protocol label switch [MPLS] · CPC title

• H04L45/24

  Multipath · CPC title

• H04J3/1652

  Optical Transport Network [OTN] · CPC title

• H04J14/0273

  using optical overhead, e.g. overhead processing · CPC title