Method and system for automatically identifying a logical circuit failure in a data network

• US 8,203,933 B2
• Filed: 12/23/2003
• Issued: 06/19/2012
• Est. Priority Date: 12/23/2003
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Taylor, William, Massengill, David, Hollingsworth, John
• Primary Examiner(s): Phung, Luat
• Application Number:
  US10/745,170
• Publication Number:
  US 20050172174A1
• Time in Patent Office: 3,101 Days
• Field of Search: 370/242, 370/244, 370/250, 370/216, 370/217, 370/218, 370/219, 370/221, 370/389, 370/395.1, 714/4, 714/43
• US Class Current: 370/217
• CPC Class Codes: H04L 41/0233 Object-oriented techniques, for representation of network management data, e.g. common object request broker architecture [CORBA]
• CPC Class Codes: H04L 43/0817 by checking functioning

Abstract

For automatically identifying a failure in a logical circuit in a data network without manual intervention, the logical circuit includes one or more logical connections for communicating data in the data network. A network management module periodically requests trap data indicating the status of the logical connections in the logical circuit. After the trap data has been received by the network management module, the trap data is analyzed to determine whether any of the logical connections has failed. If it is determined that a logical connection has failed, the network management module may wait a predetermined time period to determine whether the failed logical connection has been restored. If after the predetermined time period the logical connection has not been restored, then the logical circuit is identified as having failed.

Claims

1. A method for automatically identifying a failure in a logical circuit in a data network, the method comprising:

polling first and second switches in the logical circuit of the data network based on a predetermined schedule to retrieve status information associated with a failure status of at least one of a first network-to-network interface or a second network-to-network interface, wherein the logical circuit connects a host device to a remote device via first and second local access and transport areas and an inter-exchange carrier, wherein the host device is in communication with the first local access and transport area, wherein the first local access and transport area is in communication with the inter-exchange carrier via the first switch in the first local access and transport area forming the first network-to-network interface, wherein the inter-exchange carrier is in communication with the second local access and transport area via the second switch in the second local access and transport area forming the second network-to-network interface, and wherein the second local access and transport area is in communication with the remote device; and

identifying a failure of the logical circuit based on the status information without manual intervention, wherein identifying the failure of the logical circuit comprises determining if at least one frame has been discarded.

2. The method of claim 1, wherein polling the first and second switches in the first and second local access and transport areas comprises periodically requesting trap data stored at the first and second switches and not retrieved from the first and second switches until the polling.

3. The method of claim 1, wherein identifying the failure of the logical circuit comprises:

analyzing the status information;

if the status information indicates that the at least one of the first or second network-to-network interfaces is no longer communicating data, then determining that the at least one of the first or second network-to-network interfaces has failed;

after determining that the at least one of the first or second network-to-network interfaces has failed, waiting a predetermined time period to determine whether the at least one of the first or second network-to-network interfaces has been restored; and

if after the predetermined time period, the at least one of the first or second network-to-network interfaces has not been restored, indicating that the logical circuit has failed.

4. The method of claim 1 further comprising:

identifying a logical identifier for the logical circuit; and

based on the logical identifier, accessing a database to identify a first logical connection associated with the first network-to-network interface and a second logical connection associated with the second network-to-network interface.

5. The method of claim 4, wherein the logical identifier is a data link connection identifier (DLCI).

6. The method of claim 4, wherein the logical identifier is a virtual path/virtual circuit identifier (VPI/VCI).

7. The method of claim 1, wherein the logical circuit is a permanent virtual circuit.

8. The method of claim 1, wherein the logical circuit is a switched virtual circuit.

9. The method of claim 1, wherein the data network is a frame relay network.

10. The method of claim 1, wherein the data network is an asynchronous transfer mode (ATM) network.

11. The method of claim 1, further comprising rerouting data from the logical circuit to a failover circuit in response to identifying the failure of the logical circuit to bypass the first and second network-to-network interfaces and the inter-exchange carrier.

12. The method of claim 1, wherein the logical circuit includes a first variable communication path through the first local access and transport area, a second variable communication path through the second local access and transport area, a first fixed communication path between the first local access and transport area and the inter-exchange carrier, and a second fixed communication path between the inter-exchange carrier and the second local access and transport area.

13. A system for automatically identifying a logical circuit failure in a data network, the system comprising:

a first network device in a first local access and transport area forming a first network-to-network interface connecting the first local access and transport area to an inter-exchange carrier to establish a logical circuit connecting the first local access and transport area to a second local access and transport area via the inter-exchange carrier, the network device to collect status information indicative of a failure status of the first network-to-network interface;

a logical element module in communication with the first network device to receive the status information, the logical element module further in communication with a second network device of the second local access and transport area, the second network device forming a second network-to-network interface connecting the inter-exchange carrier to the second local access and transport area; and

a network management module, in communication with the logical element module, to;

periodically monitor the logical circuit for the status information, wherein periodically monitoring the logical circuit comprises polling only switches carrying logical circuits indicating a problem;

periodically retrieve the status information through the polling when the logical circuit indicates a problem; and

identify a failure of the logical circuit based on the status information without manual intervention.

14. The system of claim 13, wherein the network management module identifies the failure of the logical circuit by:

analyzing the status information;

if the status information indicates that the first network-to-network interface is no longer communicating data, determining that the first network-to-network interface has failed;

after determining that the first network-to-network interface has failed, waiting a predetermined time period to determine whether the first network-to-network interface has been restored; and

if after the predetermined time period, the first network-to-network interface has not been restored, indicating that the logical circuit has failed.

15. The system of claim 13, further comprising a database for storing a logical identifier for the logical circuit.

16. The system of claim 15, wherein the network management module is operative to access the database and is further operative to:

retrieve the logical identifier for the logical circuit; and

based on the logical identifier, identify each of the first and second network-to-network interfaces in the logical circuit.

17. The system of claim 15, wherein the logical identifier is a data link connection identifier (DLCI).

18. The system of claim 15, wherein the logical identifier is a virtual path/virtual circuit identifier (VPI/VCI).

19. The system of claim 13, wherein the logical circuit is a permanent virtual circuit.

20. The system of claim 13, wherein the logical circuit is a switched virtual circuit.

21. The system of claim 13, wherein the first and second network-to-network interfaces form a frame relay network.

22. The system of claim 13, wherein the first and second network-to-network interfaces form an asynchronous transfer mode (ATM) network.

23. The system of claim 13, wherein the network management module is further to initiate a reroute procedure to reroute data from the logical circuit to a failover circuit in response to identifying the failure of the logical circuit to bypass the first and second network-to-network interfaces and the inter-exchange carrier.

24. The system of claim 13, wherein the logical circuit includes a first variable communication path through the first local access and transport area, a second variable communication path through the second local access and transport area, a first fixed communication path between the first local access and transport area and the inter-exchange carrier, and a second fixed communication path between the inter-exchange carrier and the second local access and transport area.

25. A method for automatically identifying a failure in a logical circuit in a data network, the method comprising:

after identifying the existence of a problem in the logical circuit, polling a first network device of the logical circuit to retrieve first status information, the logical circuit connecting a host device to a remote device via first and second local access and transport areas and an inter-exchange carrier, the first network device forming a first network-to-network interface connecting the first local access and transport area to the inter-exchange carrier, and the first status information indicative of a failure status of the first network-to-network interface;

after confirming a failure in the first network-to-network interface based on the first status information, determining whether the first network-to-network interface has been restored after waiting a predetermined duration; and

when the first network-to-network interface has not been restored after the predetermined duration, indicating that the logical circuit has failed; and

after indicating that the logical circuit has failed, rerouting data via a failover network in communication with the first and second local access and transport areas to bypass the first network-to-network interface, the inter-exchange carrier, and a second network-to-network interface connecting the inter-exchange carrier to the second local access and transport area.

26. The method of claim 25, wherein the failure of the logical circuit indicates that the logical circuit is no longer communicating data.

27. The method of claim 25, wherein the polling of the first network device is performed by a network management system in communication with the first network device and a second network device in the second local access and transport area, wherein the network management system further polls the second network device for second status information indicative of a failure status of the second network-to-network interface, and wherein the network management system is not part of the logical circuit.

28. The method of claim 25, wherein the logical circuit includes a first variable communication path through the first local access and transport area, a second variable communication path through the second local access and transport area, a first fixed communication path between the first local access and transport area and the inter-exchange carrier, and a second fixed communication path between the inter-exchange carrier and the second local access and transport area.