Apparatus, system and method capable of recovering from disjoint clusters in an mesh network

• US 20060193334A1
• Filed: 02/25/2005
• Published: 08/31/2006
• Est. Priority Date: 02/25/2005
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Hazra, Mousumi, Demirhan, Mustafa, Kushalnagar, Nandakishore
• Granted Patent: US 7,580,364 B2
• Time in Patent Office: Days
• US Class Current: 370/400
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 40/24 Connectivity information management, e.g. connectivity discovery or connectivity update
• CPC Class Codes: H04W 48/08 Access restriction or access information delivery, e.g. discovery data delivery signalling during connection H04W76/00
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

An embodiment of the present invention provides an apparatus, comprising a transceiver capable of recovering from disjoint clusters in a mesh network by adding an additional Extended Service Set number (ESS Number) information element (IE) in the Beacon and Probe Response frames in at least one access point (AP) in said mesh network and all newly joining APs performing a scan of all channels to detect what channel the extended service set (ESS) is running on its ESS Number and putting this ESS number into their beacons Probe responses.

Claims

1. An apparatus, comprising:

a transceiver capable of recovering from disjoint clusters in a mesh network.

2. The apparatus of claim 1, wherein recovering from disjoint clusters in a mesh network comprises:

in at least one access point (AP) in said mesh network, adding an additional Extended Service Set number (ESS Number) information element (IE) in the Beacon and Probe Response frames and all newly joining APs performing a scan of all channels to detect what channel the extended service set (ESS) is running on its ESS Number, wherein said APs put said ESS number into their beacons Probe responses.

3. The apparatus of claim 2, wherein if said at least one AP in said mesh network detects that it is the first AP of said ESS mesh network, said at least one AP chooses its own MAC address as the ESS number and adds this number within its beacon as the ESS Number IE.

4. The apparatus of claim 3, wherein any AP in said ESS Mesh network performs fast channel scans to detect disjoint clusters.

5. The apparatus of claim 4, wherein said AP performing said fast scan is any newly joining AP during the initial scan which detects two or more clusters of networks with the same ESSID running on different channels or any APs to determine network conditions at any time it finds itself idle.

6. The apparatus of claim 4, wherein during said scan, an AP creates a table of network transmission channels and ESS numbers for the same ESSID networks and wherein when said AP detects that different clusters exist with the same ESSID, it first looks at the ESS Number of the different clusters and if it does not detect that all clusters have the same ESS number, the cluster with the smallest ESS Number is selected as the parent cluster.

7. The apparatus of claim 6, wherein if a node detects that it is not the parent cluster, it initiates a channel change process by sending out a self-configuration change channel request with the channel of the parent cluster and the corresponding ESS Number, and if it is an already operational AP, the channel change message is sent out in its current operating channel, and wherein a newly joining AP is capable of sending the channel change request in all channels with detected clusters and picking the channel of the parent cluster as its own operating channel, and every AP that receives this message sets their new ESS number, forwards this packet, and then changes its channels if necessary.

8. The apparatus of claim 5, wherein if a node detects that it is a member of the parent cluster, it starts a cluster detect timer and when this timer expires, the node checks if all clusters have joined this parent cluster and if the AP detects that some luster still exists, the network with the smaller ESS number switches its channel.

9. The apparatus of claim 4, wherein during said scan, an AP creates a table of network transmission channels and ESS numbers for the same ESSID networks and wherein when said AP detects that different clusters exist with the same ESSID, it first looks at the ESS Number of the different clusters and if it detects that all clusters have the same ESS number, it runs a new ESS Number selection algorithm for its cluster.

10. The apparatus of claim 4, wherein said ESS Number selection algorithm is a leader-election algorithm to select a leader and wherein the elected leader sends out a self-configuration message with its Mac address as the new ESS number for its cluster.

11. A method of recovering from disjoint clusters in a mesh network, comprising:

adding an additional Extended Service Set number (ESS Number) information element (IE) in the Beacon and Probe Response frames in at least one access point (AP) in said mesh network,

performing a scan by all newly joining APs of all channels to detect what channel the extended service set (ESS) is running on and its ESS Number, wherein said APs put said ESS number into their beacons Probe responses.

12. The method of claim 11, further comprising choosing its own MAC address as the ESS number if said newly joining AP is the first AP of said ESS mesh network, and adding this number within its beacon as the ESS Number IE.

13. The method of claim 12, further comprising performing fast channel scans to detect disjoint clusters by any AP in said ESS Mesh network.

14. The method of claim 13, wherein said AP performing said fast scan is any newly joining AP during the initial scan which detects two or more clusters of networks with the same ESSID running on different channels or any APs to determine network conditions at any time it finds itself idle.

15. The method of claim 13, further comprising creating a table of network transmission channels and ESS numbers for the same ESSID networks during said scan, and when said AP detects that different clusters exist with the same ESSID, looking first at the ESS Number of the different clusters and if it does not detect that all clusters have the same ESS number, the cluster with the smallest ESS Number is selected as the parent cluster.

16. The method of claim 15, further comprising initiating a channel change process by sending out a self-configuration change channel request with the channel of the parent cluster and the corresponding ESS Number if a node detects that it is not the parent cluster, and if it is an already operational AP, sending out the channel change message in its current operating channel.

17. The method of claim 16, further comprising sending, by a newly joining AP, the channel change request in all channels with detected clusters and then picking the channel of the parent cluster as its own operating channel and wherein every AP that receives this message sets their new ESS number, forwards this packet, and then changes its channels if necessary.

18. The method of claim 15, further comprising detecting if a node is a member of the parent cluster and if so starting a cluster detect timer and when this timer expires, checking by said node if all clusters have joined this parent cluster and if said node detects that some cluster still exists, the network with the smaller ESS number switches its channel.

19. The method of claim 14, further comprising creating by an AP a table of network transmission channels and ESS numbers for the same ESSID networks during said scan, and detecting by said AP when different clusters exist with the same ESSID by first looking at the ESS Number of the different clusters and detecting if all clusters have the same ESS number.

20. The method of claim 19, further comprising running a new ESS Number selection algorithm for its cluster if all of said clusters do not have the same ESS number.

21. The method of claim 20, further comprising adapting said ESS Number selection algorithm to be capable of using a leader-election algorithm to select a leader and wherein the elected leader sends out a self-configuration message with its Mac address as the new ESS number for its cluster.

22. An article, comprising:

a storage medium having stored thereon instructions, that, when executed by a computing platform results in;

recovering from disjoint clusters in a mesh network by adding an additional Extended Service Set number (ESS Number) information element (IE) in the Beacon and Probe Response frames in at least one access point (AP) in said mesh network and performing a scan by all newly joining APs of all channels to detect what channel the extended service set (ESS) is running on and its ESS Number, and putting said ESS number into their beacons Probe responses by said AP.

23. The article of claim 22, further comprising instructing choosing its own MAC address as the ESS number, if it said newly joining AP is the first AP of said ESS mesh network, and adding this number within its beacon as the ESS Number IE.

24. The article of claim 23, further comprising instructing and controlling the performance of fast channel scans to detect disjoint clusters by any AP in said ESS Mesh network.

25. The article of claim 24, wherein said AP performing said fast scan is any newly joining AP during the initial scan which detects two or more clusters of networks with the same ESSID running on different channels or any APs to determine network conditions at any time it finds itself idle.

26. A system capable of recovering from disjoint clusters in a mesh network comprising:

at least one access point (AP) in said mesh network capable of adding an additional Extended Service Set number (ESS Number) information element (IE) in the Beacon and Probe Response frames; and

at least one additional AP capable of, when newly joining the system, performing a scan of all channels to detect what channel the extended service set (ESS) is running on its ESS Number and wherein said at least one additional AP puts said ESS number into its Beacon Probe responses.