[cisco-voip] 7921G suffering from dropped calls while roaming between AP

[Paul Wozney]

> My colleague actually troubleshoot this issue and he changed the wireless phone to scan for channel 1/6/11 only (on b/g) , we disabled the A as it seems like we have a poor coverage with 802.11a.

I'm not sure if this will help, but here goes.  It sounds like you
don't have extensive overlap with your APs, so you should make sure
you have the feature 'aggressive load balancing' disabled.  This is
general wireless best practices.
http://www.cisco.com/en/US/tech/tk722/tk809/technologies_tech_note09186a0080810880.shtml#t6

And it is a specific requirement for WLANs providing voice access to
the 7920/7921s:
http://www.cisco.com/en/US/docs/wireless/controller/6.0/configuration/guide/c60ccfg.html#wp1902039

---
Paul Wozney
Network Consultant
phone: +1 604-629-9975
toll free: +1 866-748-0516
email: paul at wozney.ca
web: http://wozney.ca