Hot standby access point

• US 20040136318A1
• Filed: 01/09/2003
• Published: 07/15/2004
• Est. Priority Date: 01/09/2003
• Status: Active Grant

• Current Assignee: Modular Mining Systems Incorporated (Komatsu Ltd.)
• Original Assignee: Modular Mining Systems Incorporated (Komatsu Ltd.)
• Inventors: Bentley, Kevin R.
• Granted Patent: US 6,934,298 B2
• Time in Patent Office: Days
• US Class Current: 370/221
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

A group of wireless APs, including an active primary AP and one or more inactive backup APs, responds to the failure of the active AP. Backup APs passively detect the absence of the primary AP from a coverage area and become active. If more than one Backup AP attempts to assume the role of the primary AP, contention is resolved by applying a conflict resolution algorithm.

Claims

1. A wireless communication network providing an area of coverage, comprising:

an active primary access point available for wireless communication with mobile access stations within the area of coverage; and

one or more inactive backup access points wirelessly connected to the primary access point;

wherein the backup access points passively detect whether the primary access point is active.

2. The wireless communication network of claim 1, wherein all access points become active when turned on.

3. The wireless communication network of claim 2, wherein the backup access points listen for activity from other active access points and become active if no other activity is detected.

4. The wireless communication network of claim 3, wherein active access points listen for activity from other access points and implement a contention resolution procedure if activity is detected.

5. The wireless communication network of claim 4, wherein a contention is created between a plurality of active access points and the contention is resolved so that only one access point remains active and becomes primary access point while all other access points become inactive.

6. The wireless communication network of claim 5, wherein said contention is resolved by each active access point generating a random number representing a respective period of time;

each active access point waiting the respective period of time;

each active access point listening for activity from other access points; and

each active access point becoming inactive if said activity is detected.

7. The wireless communication network of claim 6, wherein a plurality of active primary access points is interconnected to form an expanded area of coverage.

8. The wireless communication network of claim 7, wherein the plurality of active primary access points is interconnected by another wireless communication network.

9. The wireless communication network of claim 7, wherein the plurality of active primary access points is interconnected by a wired communication network.

10. The wireless communication network of claim 7, wherein the plurality of active primary access points is interconnected by a combination of wired and wireless communication networks.

11. The wireless communication network of claim 9, wherein the wired communication network further comprises a local area network.

12. The wireless communication network of claim 10, wherein the wired communication network further comprises a local area network.

13. The wireless communication network of claim 7, wherein the plurality of active primary access points is interconnected by a telephone communication system.

14. The wireless communication network of claim 8, further comprising a satellite communication system.

15. The wireless communication network of claim 10, further comprising a satellite communication system.

16. A method of providing a redundant area of coverage in a wireless communication network, comprising the steps of:

determining a desired area of coverage;

providing an active primary access point for wirelessly connecting to mobile access points within the desired area of coverage;

wirelessly connecting one or more inactive backup access points to the primary access stations; and

programming the inactive backup access points to passively detect whether the primary access point is active.

17. The method of claim 16, wherein all access points become active when turned on.

18. The method of claim 17, wherein the backup access points listen for activity from other active access points and become active if no activity is detected.

19. The method of claim 18, wherein active access points listen for activity from other access points and implement a contention resolution procedure if activity is detected.

20. The method of claim 19, wherein a contention is created between a plurality of active access points and the contention is resolved so that only one access point remains active and becomes the primary access point while all other access points become inactive.

21. The method of claim 20, further comprising the steps of:

generating a random number representing a respective period of time for each active access point;

requiring each active access point to wait the respective period of time;

directing each active access point to listen for activity from other access points; and

having each active access point become inactive if said activity is detected.

22. The method of claim 21, further comprising interconnecting a plurality of active primary access points to form an expanded area of coverage.

23. The method of claim 22, wherein the plurality of active primary access points is interconnected by another wireless communication network.

24. The method of claim 22, wherein the plurality of active primary access points is interconnected by a wired communication network.

25. The method of claim 22, wherein the plurality of active primary access points is interconnected by a combination of wired and wireless communication networks.

26. The method of claim 22, wherein the plurality of active primary access points is interconnected by a telephone communication system.

27. The method of claim 23, further comprising transmitting and receiving communications over a satellite communication system.

28. The method of claim 25, further comprising transmitting and receiving communications over a satellite communication system.