Method for optimizing the frequency of network topology parameter updates

• US 7,990,885 B2
• Filed: 05/29/2009
• Issued: 08/02/2011
• Est. Priority Date: 09/24/2004
• Status: Active Grant

• Current Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Original Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Inventors: Rajan, Govinda Nallappa
• Primary Examiner(s): Pezzlo; John
• Application Number:
  US12/474,961
• Publication Number:
  US 20090232027A1
• Time in Patent Office: 795 Days
• Field of Search: 370/254, 370/252, 370/389
• US Class Current: 370/252
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 43/00 Arrangements for monitoring or testing data switching networks
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 43/0847 Transmission error
• CPC Class Codes: H04L 43/0852 Delays
• CPC Class Codes: H04L 43/0882 Utilisation of link capacity
• CPC Class Codes: H04L 43/16 Threshold monitoring

Abstract

Accuracy of network topology information and efficient usage of available bandwidth when broadcasting topology updates are optimized in accordance with the principles of the present invention by collecting and utilizing locally known network usage information to update the network topology information between regular updates. This information is then used in establishing paths for end user communication through the network. It is further used to determine which network topology information is to be included in a subsequent update broadcast by the node. Additionally, it is used to tune adaptively the frequency with which updates are broadcast by the node.

Claims

1. In a data communication network comprising a plurality of nodes interconnected by links to form communications paths between the nodes, each node adapted to transmit and store network topology information at least about itself toward one or more nodes in the network, a method comprising:

monitoring a change for a network characteristic associated with a node of the plurality of nodes;

classifying the change observed during the monitoring into one of a plurality of classification groups associated with the network characteristic; and

transmitting topology update information toward one or more nodes of the plurality of nodes,

wherein a transmission frequency associated with the transmitting of the topology information is determined based on at least the classification group, and

wherein at least two of the plurality of classification groups are associated with different transmission frequencies.

2. The method of claim 1, wherein the change for the network characteristic is identified by one of an actual change of the network characteristic and a rate of change of the network characteristic.

3. The method of claim 1, wherein content of the topology update information is determined based on at least one or more classification groups identified by classifying changes of one or more network characteristics associated with the node.

4. The method of claim 2, further comprising

eliminating information about a selected network characteristic from the topology update information being transmitted when a respective change is below a prescribed threshold.

5. The method of claim 2, further comprising:

including a selected node characteristic into the topology update information being transmitted when a respective change is greater than a prescribed threshold.

6. The method of claim 1, further comprising:

including a selected node characteristic into the topology update information being transmitted when a respective change has a rate greater than a prescribed rate.

7. The method of claim 1, further comprising:

determining the one or more nodes for receiving the topology update information based on one or more classification groups to which changes of at least one network characteristic associated with the one or more nodes are classified to.

8. The method of claim 1, wherein the network characteristic associated with a node comprises one of a network characteristic of the node and a network characteristic of one or more links connected to the node.

9. The method of claim 1, further comprising:

receiving, at the node, topology information associated with at least one other node of the plurality of nodes, wherein at least one of;

a frequency with which the topology information is received and content of the topology information, is based on one or more classification groups to which changes of one or more network characteristics associated with the at least one node are classified to.

10. The method of claim 1, wherein the topology update information being transmitted comprises information about one or more changes of respective one or more network characteristics associated with the node.

11. In a data communication network comprising a plurality of nodes interconnected by links to form communications paths between the nodes, each node capable of transmitting and storing network topology information at least about itself toward one or more nodes in the network, a method comprising the steps of:

monitoring a change for a characteristic of a node;

classifying the node characteristic into one of at least two groups, each group representing a substantially similar node characteristic change observed during the monitoring, one group representing a substantially different change from other groups in the at least two groups; and

transmitting the network topology information to one or more nodes of the plurality of nodes more frequently when the node characteristic is classified into the first group than when the node characteristic is classified into the second group.

12. The method as defined in claim 11, further comprising:

eliminating a selected node characteristic from the network topology information being transmitted when the selected node characteristic is classified into the second group.

13. The method as defined in claim 11, further comprising:

including a selected node characteristic in the network topology information being transmitted when the selected node characteristic changes by at least a prescribed amount.

14. The method as defined in claim 11, further comprising:

including a selected node characteristic in the network topology information being transmitted when the selected node characteristic changes at a rate greater than or equal to a prescribed rate.

15. The method as defined in claim 11, further comprising:

including a selected node characteristic in the network topology information being transmitted when the selected node characteristic changes at a rate greater than or equal to a prescribed rate;

eliminating a selected node characteristic from the network topology information being transmitted when the selected node characteristic is classified into the second group; and

targeting a subset of nodes to receive updated network topology information based on respective groups to which characteristics of each node in the subset and one or more links associated therewith are assigned, wherein the one or more nodes are the subset of nodes targeted.

16. In a data communication network comprising a plurality of nodes interconnected by links to form communications paths between the nodes, each node capable of transmitting and storing network topology information at least about itself toward one or more nodes in the network, a method comprising:

receiving a path set-up request identifying nodes and links assigned to a communication path being established in the network;

updating network topology information within the node in response to the path set-up request to generate a locally updated set of the network topology information reflecting link and node characteristic changes caused within the network by the path setup request;

receiving a globally updated set of the network topology information; and

analyzing the globally updated set and the locally updated set to assign a reliability factor for characteristics of each node and each link in the network topology information, the reliability factor being indicative of differences between the globally updated set and the locally updated set.

17. The method of claim 16, further comprising:

establishing a path through the network in response to a path set-up request utilizing only links and nodes having predetermined topology characteristics whose associated reliability factors that are indicative of substantially high reliability.

18. The method of claim 16, further comprising:

requesting network topology information from a selected node having at least one characteristic that has an associated reliability factor indicative of substantially low reliability.

19. The method of claim 18, wherein the requesting the network topology information from the selected node comprises:

requesting frequency updates of the network topology information from the selected node.