Smart roam system and method

• US 9,526,058 B2
• Filed: 02/09/2011
• Issued: 12/20/2016
• Est. Priority Date: 02/10/2010
• Status: Active Grant

• Current Assignee: Lantronix Incorporated
• Original Assignee: Lantronix Incorporated
• Inventors: Kakkad, Vishal
• Primary Examiner(s): Kassim, Khaled
• Assistant Examiner(s): Yang, Zhaohui
• Application Number:
  US13/024,247
• Publication Number:
  US 20110194532A1
• Time in Patent Office: 2,141 Days
• Field of Search: 370328-338
• US Class Current: 1/1
• CPC Class Codes: H04W 12/062 Pre-authentication
• CPC Class Codes: H04W 36/0077 of access information of target access point
• CPC Class Codes: H04W 36/0094 Definition of hand-off measurement parameters
• CPC Class Codes: H04W 36/30 by measured or perceived connection quality data
• CPC Class Codes: H04W 36/302 due to low signal strength

Abstract

Systems and methods for determining when to switch wireless access points from a current wireless access point to a new wireless access point are disclosed. In various embodiments the systems and methods monitor a signal strength received from the current wireless access point, monitor a signal strength received from the new wireless access point and compare the signal strength received from the wireless access points. Switching from the current wireless access point to the new wireless access point can occur, for example, when the signal strength received from the new wireless access point is greater than the signal strength received from the current wireless access point by a first pre-determined value.

Claims

1. A method for determining when to switch a wireless device'"'"'s connection from a current wireless access point to a new wireless access point comprising the following steps:

setting a previously monitored signal strength from the current wireless access point as a threshold;

progressively monitoring a signal strength received from the current wireless access point,

wherein monitoring takes into account one of signal-to-noise ratio and bit-error rate;

monitoring a signal strength, received from the new wireless access point;

comparing the signal strengths received from the wireless access points;

comparing the received signal strength received from the current wireless access point with the threshold;

pre-authenticating the wireless device with the new wireless access point prior to the steps of comparing the signal strengths and comparing the received signal strength from the current wireless access point with the threshold, wherein pre-authenticating the wireless device comprises pre-negotiating of one or more security associations; and

the using pre-authentication to switch the wireless device'"'"'s connection from the current wireless access point to the new wireless access point when the signal strength received from the new wireless access point is greater than the signal strength received from the current wireless access point by a pre-determined difference value and when the signal strength received from the current wireless access point is less than the threshold.

2. The method of claim 1, further comprising reducing the threshold when the signal strength received from the current access point and the new access point are both below the threshold.

3. The method of claim 1, further comprising comparing the signal strength received from the current access point to multiple new access points to determine if a switch should occur.

4. The method of claim 3, wherein the multiple new access points are grouped into at least two groups and each new access point in a group is monitored before switching to another group.

5. The method of claim 1, wherein the step of monitoring the signal strength received from the current wireless access point comprises passively scanning a beacon signal from the current wireless access point.

6. The method of claim 1, wherein the step of pre-authenticating the device with the new wireless access point occurs when the wireless device is out of range of the new wireless access point.

7. The method of claim 1, wherein the step of pre-authenticating the device with the new wireless access point comprises splitting a pre-negotiation into a plurality of data transmissions.

8. The method of claim 1, further comprising setting, in response to switching the wireless device'"'"'s connection from the current wireless access point to the new wireless access point, the monitored signal strength received from the new wireless access point as the threshold.

9. A client-side wireless device comprising:

an antenna;

a receiver, coupled to the antenna;

a processor coupled to the receiver and configured to control a functionality of the wireless device;

a memory coupled to the processor and storing instructions to cause the processor to;

set a previously monitored signal strength from the current wireless access point as a threshold;

progressively monitoring a signal strength received from the current wireless access point,

wherein monitoring takes into account one of signal-to-noise ratio and bit-error rate;

monitor a signal strength received from the new wireless access point;

compare the received signal strengths of the wireless access points;

compare the received signal strength received from the current wireless access point with the threshold;

pre-authenticate the client-side wireless device with the new wireless access point prior to the steps, of comparing the signal strengths and comparing the received signal strength from the current wireless access point with the threshold wherein pre-authenticating the client-side wireless device comprises pre-negotiating of one or more security associations; and

use the pre-authentication to switch the wireless device'"'"'s connection from the current wireless access point to the new wireless access point when the received signal strength of the new wireless access point is greater than the received signal strength of the current wireless access point by a pre-determined difference value and when the signal strength received from the current wireless access point is less than the threshold.

10. The wireless device of claim 9, wherein the instructions further cause the processor to reduce the threshold when the received signal strength of the current access point and the new access point are both below threshold.

11. The wireless device of claim 9, wherein the instructions further cause the processor to compare the received signal strength of the current access point to multiple new access points to determine if a switch should occur.

12. The wireless device of claim 11, wherein the multiple new access points are grouped into at least two groups and each new access point in a group is monitored before switching to another group.

13. The wireless device of claim 9, wherein the instruction, to monitor the signal strength received from the current wireless access point comprises passively scanning a beacon signal strength received from the current wireless access point.

14. The method of claim 9, wherein the instructions further cause the processor to pre-authenticate the client-side wireless device when the client-side wireless device is out of range of the new wireless access point.

15. The method of claim 9, wherein the instructions further cause the processor to split a pre-negotiation into a plurality of data transmissions and use those data transmissions to pre-authenticate the client-side wireless device.

16. The method of claim 9, wherein the instructions further cause the processor to set, in response to switching the wireless device'"'"'s connection from the current wireless access point to the new wireless access point, the monitored signal strength received from the new wireless access point as the threshold.