Hot standby access point

• US 6,934,298 B2
• Filed: 01/09/2003
• Issued: 08/23/2005
• 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.
• Primary Examiner(s): Pham, Chi
• Assistant Examiner(s): George, Keith M.
• Application Number:
  US10/339,050
• Publication Number:
  US 20040136318A1
• Time in Patent Office: 957 Days
• Field of Search: 370/328, 370/338, 370/216, 370/401, 370/445, 370/447, 370/461, 370/462
• US Class Current: 370/447
• 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, wherein said active primary access point is adapted to listen for activity from other access points and implement a contention resolution procedure if activity is detected; and

at least one inactive backup access point wirelessly connected to the primary access point;

wherein the at least one backup access point passively detects whether any other access points are 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 at least one backup access point listens 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 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 active primary access point while all other access points become inactive.

5. The wireless communication network of claim 4, 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.

6. The wireless communication network of claim 5, wherein a plurality of active primary access points is interconnected to form an expanded area of coverage.

7. The wireless communication network of claim 6, wherein the plurality of active primary access points is interconnected by another wireless communication network.

8. The wireless communication network of claim 7, further comprising a satellite communication system.

9. The wireless communication network of claim 6, wherein the plurality of active primary access points is interconnected by a wired communication network.

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

11. The wireless communication network of claim 6, wherein the plurality of active primary access points is interconnected by a combination of wired and wireless communication networks.

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

13. The wireless communication network of claim 11, further comprising a satellite communication system.

14. The wireless communication network of claim 6, wherein the plurality of active primary access points is interconnected by a telephone communication system.

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

providing an active primary access point adapted to provide a wireless connection to at least one mobile access point and to initiate a contention resolution procedure if activity is detected on the wireless connection;

wirelessly connecting at least one inactive backup access point to the active primary access point; and

programming the at least one inactive backup access point to passively detect whether the active primary access point is active.

16. The method of claim 15, wherein all access points become active when turned on.

17. The method of claim 16, wherein the at least one backup access point listens for activity from other active access points and becomes active if no activity is detected.

18. The method of claim 17, 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 active primary access point while all other access points become inactive.

19. The method of claim 18, 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.

20. The method of claim 19, further comprising interconnecting a plurality of active primary access points to form an expanded area of coverage.

21. The method of claim 20, wherein the plurality of active primary access points is interconnected by another wireless communication network.

22. The method of claim 21, further comprising transmitting and receiving communications over a satellite communication system.

23. The method of claim 20, wherein the plurality of active primary access points is interconnected by a wired communication network.

24. The method of claim 20, wherein the plurality of active primary access points is interconnected by a combination of wired and wireless communication networks.

25. The method of claim 24, further comprising transmitting and receiving communications over a satellite communication system.

26. The method of claim 20, wherein the plurality of active primary access points is interconnected by a telephone communication system.