We have 2 WLCs (4404 running 5.2.193) at hub site A. We have around 25 APs each (LAP1142N) at site A and a remote site B.
- Both sites use similar hardware and software on the clients.
- APs from both these locations are assigned to the same controller and same AP group.
- Both use the same WLAN (using WPA2/AES encryption).
- Both sites have clients that support 802.11n.
- The driver software is using version that supports WPA2. BIOS has been updated as well.
- We have tried at least 2 different wlan supplicants.
- we don't have access to a wireless sniffer yet. Efforts to use the LAP1142N as a sniffer did not yield good information.
Problem is that clients at site B (operating at 802.11n) suffer performance issues. Another symptom observed is that these clients handoff between multiple APs during this time which may be causing the performance issues. Environmental conditions should be OK as this is a normal office building and I can experience these issues even when the closest AP is less than 15 feet away (or even sitting at my own desk at site B).
The same clients, when configured to disable 802.11n operation on their machines work fine (over 802.11g). One more important observation is that sometimes during our testing, we used another WLAN using WEP (and not WPA2) to see if this was related to the encryption protocol, but the issue persisted.
We have fixed another issue since and that was the APs at site B were showing up in 2 diffferent AP groups, no matter which controller we chose. Even if we removed those APs from the group (any of the 2), it will remove them from both the groups and upon adding them back to one group, they would shop up as part of both those AP groups. Finally, we moved them to the 3rd AP group successfully (without them showing up in another AP group).
But, despite these, we continue to see performance issues randomly. So I would appreciate some ideas from this forum. Has anyone experienced similar issues in similar environments?