Wireless Transit Link Discovery and Establishment

• US 20080069029A1
• Filed: 10/13/2005
• Published: 03/20/2008
• Est. Priority Date: 10/13/2004
• Status: Abandoned Application

• Current Assignee: Apple Inc.
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Chow, Jarry
• Application Number:
  US11/577,271
• Publication Number:
  US 20080069029A1
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04L 67/63 Routing a service request depending on the request content or context
• CPC Class Codes: H04W 40/06 based on characteristics of available antennas
• CPC Class Codes: H04W 76/14 Direct-mode setup
• CPC Class Codes: H04W 76/15 Setup of multiple wireless link connections
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

The present invention provides a technique for allowing neighboring nodes to dynamically discover the existence of each other and establish transit links therebetween. The discovery process includes providing a channel assessment among a number of communication channels based on channel traffic or characteristics of the channel traffic. Based on the channel assessment, a candidate channel is selected and the mesh node will begin transmitting discovery messages and listening for responses to the discovery messages from neighboring mesh nodes. Upon receipt of a response, the mesh node can determine whether a transit link can and should be established with the neighboring node. During establishment of a transit link, a lower layer communication link is established with the neighboring mesh node for scheduling and authentication of the respective mesh nodes with respect to each other, prior to activation of the transit link itself. The transit link will be used for forwarding data.

Claims

1. A method for allowing a mesh node to discover a neighboring mesh node in a mesh network comprising:

providing a channel assessment for a plurality of communication channels based on channel traffic or characteristics of the channel traffic present on the plurality of communication channels;

selecting a candidate channel from the plurality of communication channels based on the channel assessment;

transmitting a discovery message over the candidate channel; and

receiving a response to the discovery message from the neighboring mesh node, wherein receiving the response is indicative of being able to establish a transit link with the neighboring mesh node.

2. The method of claim 1 further comprising determining whether to establish the transit link with the neighboring mesh node.

3. The method of claim 1 further comprising establishing the transit link with the neighboring mesh node.

4. The method of claim 3 wherein establishing the transit link further comprises:

activating a lower layer communication link with the neighboring mesh node for link layer communications; and

activating a higher layer communication link with the neighboring mesh node to represent the transit link for data transfer.

5. The method of claim 3 further comprising interacting with the neighboring mesh node to establish a schedule for further communications related to establishing the transit link.

6. The method of claim 3 further comprising interacting with the neighboring mesh node to facilitate mutual authentication.

7. The method of claim 1 wherein the transit link is established on the candidate channel.

8. The method of claim 1 wherein the transit link is established on a channel other than the candidate channel.

9. The method of claim 1 wherein providing the channel assessment comprises cycling through at least some of the plurality of communication channels and analyzing the channel traffic or characteristics of the channel traffic on each of the cycled plurality of communication channels.

10. The method of claim 9 wherein analyzing the channel traffic comprises detecting discovery messages related to other nodes, including the neighboring mesh node, discovering one another or establishing transit links.

11. The method of claim 9 wherein the characteristics of the channel traffic bear on at least one of the group consisting of signal strength, interference, and traffic volume.

12. The method of claim 1 further comprising selecting a dwelling period having a defined length during which the discovery message is repeatedly transmitted.

13. The method of claim 12 wherein the dwelling period is selected based on a possible discovery process being implemented by the neighboring node.

14. The method of claim 13 wherein the dwelling period is based on an amount of time the neighboring node takes to provide a discovery process for a plurality of antennas.

15. The method of claim 1 wherein the discovery message is indicative of the mesh node being isolated from the mesh network.

16. The method of claim 1 wherein the discovery message is indicative of the mesh node being connected to the mesh network.

17. The method of claim 1 further comprising:

receiving a discovery message from the neighboring mesh node during the channel assessment; and

interacting with the neighboring mesh node to establish the transit link.

18. The method of claim 1 wherein the mesh node provides a plurality of directional antennas providing directional coverage areas in different directions, and further comprising systematically attempting to discover neighboring nodes and establish transit links with the neighboring nodes for each of the plurality of antennas.

19. The method of claim 1 wherein the transit link is a communication link within the mesh network used for forwarding traffic, which is part of a communication session between two communication terminals.

20. The method of claim 1 further comprising facilitating communications with communication terminals to provide access to the mesh network for the communication terminals.

21. The method of claim 20 further comprising facilitating communications for forwarding data to and from other neighboring nodes in the mesh network.

22. A mesh node adapted to discover a neighboring mesh node in a mesh network comprising:

a first communication interface adapted to facilitate communications with other mesh nodes, including the neighboring mesh node, which form part of the mesh network;

a second communication interface adapted to facilitate communications with communication terminals requiring access to the mesh network; and

a control system associated with the first and second communication interfaces and adapted to;

provide a channel assessment for a plurality of communication channels based on channel traffic or characteristics of the channel traffic present on the plurality of communication channels;

select a candidate channel from the plurality of communication channels based on the channel assessment;

transmit a discovery message over the candidate channel; and

receive a response to the discovery message from the neighboring mesh node, wherein receiving the response is indicative of being able to establish a transit link with the neighboring mesh node.

23-42. -42. (canceled)