Fast remote failure notification

• US 20090010153A1
• Filed: 07/03/2007
• Published: 01/08/2009
• Est. Priority Date: 07/03/2007
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Filsfils, Clarence, Ward, David, Previdi, Stefano
• Granted Patent: US 8,488,444 B2
• Time in Patent Office: Days
• US Class Current: 370/218
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• 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 method and system for failure notification at a remote node in communication with a local node are disclosed. The local node is configured for faster failure detection than the remote node. In one embodiment, the method includes establishing a failure monitoring session between the local node and the remote node, receiving at the remote node, a failure notification from the local node, the failure notification sent using a protocol of the failure monitoring session, and rerouting traffic at the remote node in response to the failure notification.

Claims

1. A method for failure notification at a remote node in communication with a local node, the local node configured for faster failure detection than the remote node, the method comprising:

establishing a failure monitoring session between the local node and the remote node;

receiving at the remote node, a failure notification from the local node, the failure notification sent using a protocol of the failure monitoring session; and

rerouting traffic at the remote node in response to the failure notification.

2. The method of claim 1 wherein establishing a failure monitoring session comprises establishing a Bidirectional Forwarding Detection (BFD) session.

3. The method of claim 2 wherein receiving a failure notification comprises receiving a failure notification packet from a backup path extending from the local node to the remote node.

4. The method of claim 1 wherein establishing a failure monitoring session comprises assigning a unique identifier to each interface at the remote node.

5. The method of claim 1 wherein establishing a failure monitoring session comprises establishing multiple failure monitoring sessions between the local node and the remote node and assigning a unique identifier to each session.

6. The method of claim 1 wherein rerouting traffic at the remote node comprises initiating a Fast Reroute at the remote node.

7. The method of claim 1 wherein rerouting traffic at the remote node comprises initiating a convergence process at the remote node.

8. A system for failure notification at a remote node in communication with a local node, the local node configured for faster failure detection than the remote node, the system comprising:

a processor configured for establishing a failure monitoring session between the local node and the remote node, receiving a failure notification from the local node, the failure notification sent using a protocol of the failure monitoring session, and rerouting traffic at the remote node in response to the failure notification; and

memory for storing a local node identifier and a remote node identifier.

9. The system of claim 8 wherein the memory is configured for storing an identifier for each interface at the remote node.

10. The system of claim 8 wherein said identifiers are Bidirectional Forwarding Detection (BFD) discriminators.

11. The system of claim 8 wherein establishing a failure monitoring session comprises establishing multiple failure monitoring sessions between the local node and the remote node and assigning a unique identifier to each session.

12. A method for providing failure notification to a remote node in communication with a local node, the local node configured for faster failure detection than the remote node, the method comprising:

establishing one or more failure monitoring sessions between the local node and the remote node;

identifying a failure; and

transmitting a failure notification from the local node to the remote mode using the one or more failure monitoring sessions.

13. The method of claim 12 wherein establishing one or more failure monitoring sessions comprises establishing one or more Bidirectional Forwarding Detection (BFD) sessions.

14. The method of claim 13 further comprising transmitting echo packets to the remote mode to monitor a connection between the local node and the remote node.

15. The method of claim 12 wherein identifying a failure comprises identifying a failure in a connection between the local node and the remote node, the failure monitoring session established over said connection.

16. The method of claim 12 wherein said failure is not identified by said failure monitoring session.

17. The method of claim 12 wherein establishing one or more failure monitoring session comprises assigning a unique identifier to each of said one or more failure monitoring sessions.

18. The method of claim 12 further comprising rerouting traffic to the remote node after identifying said failure.

19. A system for providing failure notification to a remote node in communication with a local node, the local node configured for faster failure detection than the remote node, the system comprising:

means for establishing one or more failure monitoring sessions between the local node and the remote node;

means for identifying a failure; and

means for transmitting a failure notification from the local node to the remote mode using the one or more failure monitoring sessions.

20. The system of claim 19 wherein said failure monitoring session is a Bidirectional Forwarding Detection (BFD) session.