Method for monitoring a network

• US 7,177,927 B1
• Filed: 08/22/2000
• Issued: 02/13/2007
• Est. Priority Date: 08/22/2000
• Status: Expired due to Fees

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Cahn, Robert
• Primary Examiner(s): Jaroenchonwanit; Bunjob
• Assistant Examiner(s): LIN, KENNY S
• Application Number:
  US09/643,473
• Time in Patent Office: 2,366 Days
• Field of Search: 709/224, 709/238, 709/239, 709/241, 370/216, 370/225, 370/227, 370/221, 370/230, 370/254, 370/351, 370/238, 370/228, 714/4, 714/57, 702/185
• US Class Current: 709/224
• CPC Class Codes: H04L 41/0663 Performing the actions predefined by failover planning, e.g. switching to standby network elements
• CPC Class Codes: H04L 41/0896 Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0817 by checking functioning
• CPC Class Codes: H04L 43/16 Threshold monitoring

Abstract

The method disclosed monitors the status of a network by a network management system that includes information describing the current network topology information describing possible restoration routes. From this information, the network management system computes three measures of network health: (1) the sum of unrouted permanent virtual circuits, (2) the sum of permanent virtual circuits whose cost exceeds a prescribed multiple of an optimal route cost and (3) the sum of permanent virtual circuits off an optimal path. Each of these measures relates to a different aspect of network health, and collectively they provide a measure of overall network performance. The method compares the measures of network health to a threshold value and selects an optimum restoration route from the stored restoration routes.

Claims

1. A method for monitoring the status of a network comprising:

computing a plurality of measures of network health, including a sum of unrouted traffic, a sum of traffic whose cost exceeds a prescribed multiple of an optimal route cost, and a sum of traffic off an optimal path; and

selecting a restoration route from a plurality of stored restoration routes based on said measures of network health.

2. The method for monitoring the status of a network of claim 1, which further comprises:

restoring circuits at a rate parameterized by a value P and observing the behavior of the network; and

increasing the value P in the network to decrease the time customers experience unrouted traffic.

3. The method for monitoring the status of a network of claim 1, which further comprises:

monitoring said measures to sense when bandwidth needs to be added to the network.

4. The method for monitoring the status of a network of claim 1, which further comprises:

derating each edge of the network to have capacity of a predetermined fraction of real capacity;

computing said plurality of measures of network health to identify unrouted, off optimal, and seriously misrouted traffic;

determining if the measures are over a specified value and if so, then adding capacity to the network.

5. A system for monitoring the status of a network, comprising:

a database storing possible restoration routes;

a computer for computing a plurality of measures of network health, including a sum of unrouted traffic, a sum of traffic whose cost exceeds a prescribed multiple of an optimal route cost, and a sum of traffic off an optimal path; and

said computer selecting a restoration route from said database storing restoration routes based on said measures of network health.

6. The system for monitoring the status of a network of claim 5, which further comprises:

means for restoring circuits at a rate parameterized by a value P and observing the behavior of the network; and

means for increasing the value P in the network to decrease the time customers experience unrouted traffic.

7. The system for monitoring the status of a network of claim 5, which further comprises:

means for monitoring said measures to sense when bandwidth needs to be added to the network.

8. The system for monitoring the status of a network of claim 5, which further comprises:

means for derating each edge of the network to have capacity of a predetermined fraction of real capacity;

said computer computing said plurality of measures of network health to identify unrouted, off optimal, and seriously misrouted traffic;

means for determining if the measures are over a specified value and if so, then adding capacity to the network.