Method and apparatus for mitigating roaming impact on communication sessions

1. A method in a client device of mitigating roaming impact on communications, the method comprising:

establishing a communication session at the client device via a first access point;

responsive to determining that a roaming criterion is satisfied, transmitting a standby indicator to the first access point and detecting a second access point;

prior to initiating a roaming process to transfer the communication session from the first access point to the second access point, determining whether a time period elapsed since receipt of a most recent beacon at the client device from the first access point exceeds a beacon threshold; and

responsive to determining that the time period exceeds the beacon threshold:

transmitting an active indicator to the first access point;

receiving a further beacon from the first access point; and

responsive to receiving the further beacon, initiating the roaming process to transfer the communication session from the first access point to the second access point.

2. The method of claim 1 , wherein the communication session is a real-time communication session.

3. The method of claim 2 , wherein the communication session includes a voice over Internet Protocol (VoIP) call.

4. The method of claim 1 , wherein determining that the roaming criterion is satisfied includes comparing a signal strength associated with the first access point to a predetermined threshold.

5. The method of claim 1 , further comprising:

responsive to receiving the further beacon, and prior to initiating the roaming process, determining whether the further beacon includes an indication that buffered data is available for the client device at the first access point.

6. The method of claim 5 , wherein the indication that buffered data is available includes a traffic indication map (TIM).

7. The method of claim 5 , further comprising:

when the further beacon includes the indication that buffered data is available for the client device, retrieving the buffered data at the client device prior to initiating the roaming process.

8. The method of claim 1 , wherein initiating the roaming process includes:

sending a further standby indicator to the first access point; and

sending an association request to the second access point.

9. The method of claim 1 , wherein the standby indicator is a QoS-Null frame containing a first power state flag.

10. The method of claim 9 , wherein the active indicator is a QoS-Null frame containing a second power state flag.

11. A client device, comprising:

a communication interface; and

a processor connected to the communication interface, the processor configured to control the communication interface to establish a communication session via a first access point;

the processor further configured, responsive to a determination that a roaming criterion is satisfied, to transmit a standby indicator via the communication interface to the first access point, and to detect a second access point;

the processor further configured, prior to initiation of a roaming process to transfer the communication session from the first access point to the second access point, to determine whether a time period elapsed since receipt of a most recent beacon at the client device from the first access point exceeds a beacon threshold; and

the processor further configured, responsive to a determination that the time period exceeds the beacon threshold, to:

transmit an active indicator to the first access point;

receive a further beacon from the first access point; and

responsive to receipt of the further beacon, initiate the roaming process to transfer the communication session from the first access point to the second access point.

12. The method of claim 11 , wherein the communication session is a real-time communication session.

13. The method of claim 12 , wherein the communication session includes a voice over Internet Protocol (VoIP) call.

14. The client device of claim 11 , wherein the processor is further configured, to determine that the roaming criterion is satisfied, to: compare a signal strength associated with the first access point to a predetermined threshold.

15. The client device of claim 14 , wherein the indication that buffered data is available includes a traffic indication map (TIM).

16. The client device of claim 14 , wherein the processor is further configured, when the further beacon includes the indication that buffered data is available for the client device, to retrieve the buffered data at the client device prior to initiation of the roaming process.

17. The client device of claim 11 , wherein the processor is further configured, responsive to receipt of the further beacon, and prior to initiation of the roaming process, to determine whether the further beacon includes an indication that buffered data is available for the client device at the first access point.

18. The client device of claim 11 , wherein the processor is configured, to initiate the roaming process, to:

send a further standby indicator to the first access point; and

send an association request to the second access point.

19. The client device of claim 11 , wherein the standby indicator is a QoS-Null frame containing a first power state flag.

20. The client device of claim 19 , wherein the active indicator is a QoS-Null frame containing a second power state flag.