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vledford Escribi?3:

Does anyone have any advice for someone experiencing random client disconnects in a dense Cisco CAPWAP/LWAPP AP deployment?

Here's some history:

The site survey for this my hospital environment was very very poor and I have inherited the mess.

The 400+ APs used to all have static channel and power assignments with the 2.4 power set to ~12mW across the board.

I have since moved to RRM using 5.2.178 code with tweaked TPC and DCA sensitivity. I'm not seeing wild DCA changes at all, but I have observed TPC to set many APs to very low power levels. (6mw,3mw,2mW, and even 1mW)

This has led me to believe that there's just too many APs in some areas, which has got me thinking about how clients would handle this. I fee like client are maybe getting confused or are unable to handle the excess of signal bouncing all around.

In some areas I have disabled the 2.4 radios on APs that were set to the abnormally low power levels and then forced RRM to recalculate. After doing so I see more normal values. I'm going to keep trying this but I would sure appreciate any advice.

The 5GHz network is looking very smooth and normal, but I know that is because of the decreased range of 5GHz. Just another reason for me to believe that I have too many 2.4 radios too close together.

The techs I work with will scream about "dead zones" but when I measure the signal everything appears normal. Does this not indicate multipath and co-channel interference?

Sounds like you need to do a packet capture to baseline your RF environment. Pick your worst area at a busy time and do a packet capture and spectrum analysis to get more information. Re-do that packet capture at a time when it is not so busy. Do the packet capture on a single channel so you can get an idea of the experience of a client on that single channel. After you do the packet captures, look at your % retries, mac and phy errors, noise floor, etc. Find your top talkers. Find out what percentage of your traffic is unicast vs. broadcast and multicast. Find out what percentage is data as opposed to management traffic. Find out how many APs you can see and at what power on that single channel. Last, but not least, do a spectrum analysis to see if anything non-802.11 is just making everything worse. Unfortunately... this is just the beginning. When you get all that information, finally do a packet capture in an area where you get good coverage and good performance and compare the data to the bad area. Somewhere in between is your ultimate solution.