Virtual path restoration scheme using fast dynamic mesh restoration in an optical network

• US 7,301,895 B2
• Filed: 02/01/2006
• Issued: 11/27/2007
• Est. Priority Date: 01/15/1999
• Status: Expired due to Fees

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Parsi, Vahid, Baghdasarian, Zareh, Zadikian, H. Michael, Saleh, Ali N.
• Primary Examiner(s): NGUYEN, HANH N
• Application Number:
  US11/345,356
• Publication Number:
  US 20060153066A1
• Time in Patent Office: 664 Days
• Field of Search: 370/225, 370/216, 370/217, 370/218, 370/221, 370/228, 370/242, 370/244, 370/245, 709/239, 709/242
• US Class Current: 370/218
• CPC Class Codes: H04J 14/0284 WDM mesh architectures
• CPC Class Codes: H04J 14/0295 Shared protection at the optical channel (1:1, n:m)
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 45/32 Flooding denial of service attacks H04L63/1458
• CPC Class Codes: H04L 45/62 Wavelength based optical switching H04Q11/0062
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0081 Fault tolerance; Redundancy; Recovery; Reconfigurability
• CPC Class Codes: H04Q 2011/0098 Mesh

Abstract

A method for restoring a virtual path, provisioned between a source and a target node, in a mesh zoned optical network is described. The method, in one embodiment, broadcasts or floods restore path requests in the network to expedite the identification of an alternate route and minimize the service disruption for failed virtual path. The flooding of requests is controlled to ensure efficient performance of the network yet guaranteeing minimum restoration time to allow critical telecommunication related traffic to flow through the network with virtually no interruption. The constant update of nodal topology by each node allows a fast identification of alternate physical path for failed virtual path.

Claims

1. A method comprising:

restoring a virtual path over a physical path in an optical network, wherein the restoring comprises;

detecting a failure within a link between a first node and a second node of the physical path,

analyzing the failure within the link to determine whether a link restoration procedure is adequate to restore the virtual path,

performing the link restoration procedure if the analyzing indicates that the link restoration procedure is adequate to restore the virtual path, wherein the link restoration procedure comprises;

transmitting a port identification query, and

receiving, in response to the port identification query, an indication of a replacement port for restoring the virtual path, and

performing a path restoration procedure if the analyzing indicates that the link restoration procedure is not adequate to restore the virtual path, wherein the path restoration procedure comprises determining an alternate physical path after the failure.

2. The method of claim 1, wherein

the link comprises a plurality of ports,

the failure within the link is a port failure of a first port within the link, and

the ports comprise the first port.

3. The method of claim 2, wherein the analyzing comprises:

determining if at least one other of the ports is available to replace the first port within the link, wherein the at least one other of the ports is a one of the ports other than the first port.

4. The method of claim 3, further comprising:

if at least one other of the ports is available to replace the first port within the link, performing the link restoration procedure.

5. The method of claim 4, wherein the link restoration procedure comprises:

restoring the virtual path to a second port of the at least one other of the ports.

6. The method of claim 4, wherein the link restoration procedure comprises:

restoring the virtual path to a second port of the at least one other of the ports using the first node.

7. The method of claim 3, further comprising:

if none of the ports other than the first port is available to replace the first port within the link, performing the path restoration procedure.

8. The method of claim 7, wherein the path restoration procedure comprises:

restoring the virtual path to the alternate physical path.

9. The method of claim 3, further comprising:

if at least one other of the ports is available within the link, performing the link restoration procedure; and

otherwise, performing the path restoration procedure.

10. The method of claim 9, wherein the path restoration procedure comprises:

restoring the virtual path to the alternate physical path.

11. The method of claim 1, wherein the path restoration procedure comprises:

broadcasting a plurality of resource request packets to a plurality of nodes in the optical network;

dynamically identifying a plurality of nodes with resources wherein the nodes with resources are ones of the nodes having a resource necessary to support the virtual path;

wherein the alternate physical path comprises ones of the nodes with resources;

configuring the alternate physical path by establishing a communication connection between the ones of the nodes with resources; and

provisioning the virtual path over the alternate physical path.

12. The method of claim 11, further comprising:

if at least one other of the ports is available to replace the first port within the link, performing the link restoration procedure.

13. The method of claim 11, further comprising:

if at least one other of the ports is available within the link, performing the link restoration procedure; and

otherwise, performing the path restoration procedure.

14. The method of claim 11, wherein:

the broadcasting the plurality of resource request packets comprises transmitting a request message from a first node of a network to a second node of the optical network,

the dynamically identifying the plurality of nodes with resources comprises temporarily allocating a resource on at least one of the first and second nodes,

the establishing the communication connection between the ones of the nodes with resources comprises receiving a response message at the first node, in response to the request message, and

the configuring the alternate physical path comprises configuring the temporarily allocated resource as a dedicated resource for the alternate physical path.

15. The method of claim 1, wherein

the transmitting the port identification query comprises the first node transmitting the port identification query to the second node on the link;

and

the receiving the indication comprises the first node receiving the indication from the second node.

16. The method of claim 1, wherein the path restoration procedure comprises acts performed by at least one node in the optical network other than the first and second nodes.

17. The method of claim 1, wherein the link restoration procedure consists of acts performed within the first and second node and acts performed between the first and second node.

20. The computer-readable medium of claim 14, further comprising:

if at least one other of the ports is available to replace the first port within the link, performing the link restoration procedure.

21. The computer-readable medium of claim 14, further comprising:

if none of the ports other than the first port is available to replace the first port within the link, performing the path restoration procedure.

22. The computer-readable medium of claim 14, further comprising:

if at least one other of the ports is available within the link, performing the link restoration procedure; and

otherwise, performing the path restoration procedure, wherein the path restoration procedure comprises restoring the virtual path to the alternate physical path.

18. A computer-readable medium having a plurality of instructions executable by a processor, wherein the plurality of instructions, when executed, cause the processor to perform a method for restoring a virtual path over a physical path in an optical network, the method comprising:

detecting a failure within a link between a first node and a second node of the physical path,

analyzing the failure within the link to determine whether a link restoration procedure is adequate to restore the virtual path,

performing the link restoration procedure if the analyzing indicates that the link restoration procedure is adequate to restore the virtual path, wherein the link restoration procedure comprises;

transmitting a port identification query, and

receiving, in response to the port identification cluery, an indication of a replacement port for restoring the virtual path, and

performing a path restoration procedure if the analyzing indicates that the link restoration procedure is not adequate to restore the virtual path, wherein the path restoration procedure comprises determining an alternate physical path after the failure.

19. The computer-readable medium of claim 18, wherein

the link comprises a plurality of ports,

the failure within the link is a port failure of a first port within the link, and

the ports comprise the first port;

wherein the analyzing comprises determining if at least one other of the ports is available to replace the first port within the link, wherein the at least one other of the ports is a one of the ports other than the first port.

23. The computer-readable medium of claim 18, wherein the path restoration procedure comprises:

broadcasting a plurality of resource request packets to a plurality of nodes in the optical network;

dynamically identifying a plurality of nodes with resources wherein the nodes with resources are ones of the nodes having a resource necessary to support the virtual path;

configuring the alternate physical path by establishing a communication connection between the ones of the nodes with resources; and

provisioning the virtual path over the alternate physical path.

24. The computer-readable medium of claim 23, further comprising:

if at least one other of the ports is available within the link, performing the link restoration procedure; and

otherwise, performing the path restoration procedure.

25. The computer-readable medium of claim 23, wherein:

the broadcasting the plurality of resource request packets comprises transmitting a request message from a first node of a network to a second node of the optical network,

the dynamically identifying the plurality of nodes with resources comprises temporarily allocating a resource on at least one of the first and second nodes,

the establishing the communication connection between the ones of the nodes with resources comprises receiving a response message at the first node, in response to the request message, and

the configuring the alternate physical path comprises configuring the temporarily allocated resource as a dedicated resource for the alternate physical path.

26. The computer-readable medium of claim 18, wherein

the transmitting the port identification query comprises the first node transmitting the port identification query to the second node on the link;

and

the receiving the indication comprises the first node receiving the indication from the second node.

27. The computer-readable medium of claim 18, wherein the path restoration procedure comprises acts performed by at least one node in the optical network other than the first and second nodes.

28. The computer-readable medium of claim 18, wherein the link restoration procedure consists of acts performed within the first and second node and acts performed between the first and second node.

30. The system of claim 24, wherein

the means for transmitting the port identification query comprises means for transmitting the port identification query from the first node to the second node on the link;

and

the means for receiving comprises means for receiving the indication of the replacement port for restoring the virtual path from the second node.

31. The system of claim 24, wherein the path restoration procedure comprises acts performed by at least one node in the optical network other than the first and second nodes.

29. A system for restoring a virtual path over a physical path in an optical network, the system comprising:

means for detecting a failure within a link between a first node and a second node of the physical path;

means for analyzing the failure within the link and deciding whether a link restoration procedure is adequate to restore the virtual path;

means for performing the link restoration procedure if the analyzing indicates that the link restoration procedure is adequate to restore the virtual path, wherein the means for performing the link restoration procedure comprises;

means for transmitting a port identification query, and

means for receiving, in response to the port identification query, an indication of a replacement port for restoring the virtual path, and

means for performing a path restoration procedure if the analyzing indicates that the link restoration procedure is not adequate to restore the virtual path, wherein the path restoration procedure comprises determining an alternate physical path after the failure.

32. The system of claim 29, wherein the link restoration procedure consists of acts performed within the first and second node and acts performed between the first and second node.