Darren,
First with the WAP4410N doesn't support seamless roaming; there is in need of a controller when we are talking about a seamless wireless connection. Now using the 4410 you need to have all three access points’ on different channels to avoid wireless interference. One Channel 1 other Channel 6 other Channel 11, this should allow for some overlap. There has to be some interference in your network since you are able to reset your laptop wireless card and reconnect and everything starts working fine.
I have a similar topology with these AP and haven't observed this behavior. I too just upgraded to latest firmware.
Have you heard of a tool call inSSIDer little minimum on what it does but it’s better than nothing. This tool will show you all wireless networks within your service area. Help you map out the locations for all your Access points.
Not sure what is all in your service area but things like other AP near your service area, Bluetooth device, cordless phones running 2.4GHz bandwidth cause issues. If you have your AP located near a kitchen where you have microwave ovens will interrupt this signal. If the AP is mounted around fluorescents lights causes EMI and causes interference. With wireless there are so many things that can cause issues. Have you measure or mapped out your services area wireless environment. Wireless signals behaviors are scattering, reflection, re-fraction, absorption, diffraction; all things in your environment will affect how wireless signal behaves with your wireless clients in your service area.
Scattering: Scattering will take place when a wireless signal hits an object that has many irregular angels causing the signal to shoot off into many directions.
Reflection: Reflection happens when the signal just completely bounces off the object. This can be a good thing and a bad thing. Reflection can be good because clients don't have to rely of LOS (Line or Sight) service. Signals can be transmitted and bounced off large buildings to a client. Reflection can be bad of it causes signals to bleed into a unneeded area.
Refraction: Refraction is the bending of your wireless signal as it goes through a medium of higher density than its origin.
Absorption: Shoot your signal at a larger brick building, concrete, and thick wood signal might be absorbed up and disappear.
Diffraction: This is often mixed up with refraction. Diffraction occurs when your wireless signal hits a very large object, slows down and actually turns around the corner. This is great if you want your signal to bend around the. Plus it slows down your signal making it weaker
Sometimes it can just be a hardware issue between the chip set of your computer and the Access point. Now I would rule that out since you have tested multiple computers with same problems.
Have you seen any common ground in where they lose signal?
When and where does the computers wireless card have to be restarted?
What time intervals are in common?
Wireless can be hectic at first to implement but once you have your service area mapped, access points placed in proper alignment with your wireless virtual map. Then everything will become stable and you shouldn’t have any more problems.
Thanks,
Jasbryan
Cisco Support Engineer
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