Method and apparatus of connectivity recovery in wireless network

• US 8,401,001 B2
• Filed: 03/28/2007
• Issued: 03/19/2013
• Est. Priority Date: 03/28/2007
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Adamovsky, Olga, Grabarnik, Maxim
• Primary Examiner(s): Appiah, Charles
• Assistant Examiner(s): COSME, NATASHA W
• Application Number:
  US11/727,724
• Publication Number:
  US 20080240145A1
• Time in Patent Office: 2,183 Days
• Field of Search: 370/350
• US Class Current: 370/350
• 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 76/19 Connection re-establishment
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 84/20 Master-slave selection or change arrangements

Abstract

A wireless communication device and a method of re-establishing a connection with a WPAN master device is presented. The method includes detecting that a first master station of a WPAN session which includes the first master device and one or more stations becomes unavailable, activating a master station application to become a second master station and sending one beacon to notify the stations of the session about the second master station connectivity parameters.

Claims

1. A method of re-establishing a session of a wireless personal area network (WPAN) by a wireless communication device of a wireless local area network (WLAN) comprising:

detecting that a master station of an association becomes unavailable, wherein the association includes at least one master station and one or more stations;

detecting that one or more other master stations operate on the association;

receiving timing synchronization function (TSF) values from each one of the one or more other master stations;

comparing the TSF values of each of the one or more other master stations with an internal TSF value; and

deciding whether or not to become a new master station according to the comparison result and if it is decided to become the new master station, becoming the new master station by activating a master station application;

sending one or more beacons that include a WPAN capabilities information element (IE) to notify the one or more stations of the association about the new master station connectivity parameters wherein the WPAN capabilities information element (IE) includes a service set identifier (SSID) and a session ID; and

creating a WPAN session with the one or more stations of the association.

2. The method of claim 1, further comprising:

receiving a connection request signal from the one or more stations of the association in order to reestablish a connection with the one or more stations of the association.

3. The method of claim 1, wherein detecting comprises:

becoming the new master station if no other master station is operating on the association.

4. The method of claim 1, wherein deciding comprises:

deciding to permit one of the one or more other stations to become a master station of the association; and

annexing one or more associated stations to the master station.

5. The method of claim 4, wherein annexing comprises:

reporting to the master station the associated stations;

preventing an unassociated station from joining the association;

becoming a client by disconnecting from the association;

and

establishing a connection with the master station as the client.

6. The method of claim 4, wherein annexing comprises:

informing the one or more associated stations on the master station; and

triggering the one or more associated stations to roam to the master station.

7. A wireless communication device comprising:

a detector to detect that a master station of an association becomes unavailable and to detect that at least one or more other master stations operate on the association, wherein the association includes at least one master station and one or more stations;

a receiver to receive timing synchronization function (TSF) values from the other master stations;

a comparator to compare the TSF values of each of the one or more other master stations with an internal TSF value;

a controller to activate a master station module to make the device a new master station according to the comparison result; and

a transmitter to, if the device becomes the new master station, send one or more beacons that include a WPAN capabilities information element (IE) to notify the one or more stations of the association about the second master station connectivity parameters wherein the WPAN capabilities information element (1E) includes a service set identifier (SSID) and a session ID in order to create a WPAN session with the one or more stations of the association.

8. The wireless communication device of claim 7 wherein the receiver is able to receive a connection request signal from the one or more stations of the association in order to reestablish a connection with the one or more stations of the association.

9. The wireless communication device of claim 7 wherein the controller permits one of the other stations to become a master station of the association and annexes one or more associated stations to the master station.

10. The wireless communication device of claim 9 wherein, while annexing, the controller is able to:

report to the master station the associated stations;

prevent an unassociated station from joining the association;

become a client of the association by disconnecting from the association; and

establishing a connection with the master station as the client.

11. The wireless communication device of claim 9, wherein while annexing the controller is able to:

inform the one or more associated stations on the master station; and

to trigger the one or more associated stations to roam to the master station.

12. The wireless communication device of claim 7, wherein the controller includes a medium access controller.

13. A wireless communication system comprising:

a wireless communication device of a wireless local area network (WLAN) able to act as a master station and as a client within association of a personal area network (WPAN), the wireless communication device comprising;

a detector to detect that a master station of an association becomes unavailable and to detect that at least one or more other master stations operate on the association, wherein the association includes at least one master station and one or more stations;

a receiver to receive timing synchronization function (TSF) values from the other master stations;

a comparator to compare the TSF values of each of the one or more other master stations with an internal TSF value;

a controller to activate a master station module to make the device a new master station according to the comparison result;

and

a transmitter to, if the device becomes the new master station, send one or more beacons that include a WPAN capabilities information element (IE) to notify the one or more stations of the association about the second master station connectivity parameters wherein the WPAN capabilities information element (IE) includes a service set identifier (SSID) and a session ID in order to create a WPAN session with the one or more stations of the association.

14. The wireless communication system of claim 13, wherein

the receiver is able to receive a connection request signal from the one or more stations of the association in order to reestablish a connection with the one or more stations of the association.

15. The wireless communication system of claim 13 wherein the controller permits one of the other stations to become a master station of the association and annexes one or more associated stations to the master station.

16. The wireless communication system of claim 15, wherein, while annexing, the controller is able to:

report to the master station the associated stations;

prevent an unassociated station from joining the association;

become a client of the association by disconnecting from the association and establishing a connection with the master station as the client.

17. The wireless communication system of claim 15 wherein while annexing the controller is able to:

inform the one or more associated stations on the master station; and

trigger the one or more associated stations to roam to the master station.