Hi Jerry:
No, there's not a concurrent connection limit on any of the wireless products, just the question of how many users can actually share a half-duplex link passing a reasonable amount of traffic. Concurrent connections doesn't sound like the problem anyway.
Troubleshooting wireless connectivity is like peeling an onion--layers on layers to isolate where the problem is. "...Performance is spotty..." could be a wireless coverage issue, where "...pretty much ceased to give out a usable address..." would likely be more of a configuration issue.
A good troubleshooting approach would be to move from the things you're sure of toward the things you're not sure of. In this scenario, you'll want to make sure that:
- wired clients that connect to ports in VLAN 10 and VLAN 21 actually get addresses they're supposed to (to rule out a DHCP problem)
- the APs are connected to switchports that are configured as trunks, allowing only VLANs 1, 10 and 21, and that VLAN 1 is native
To test that this is working correctly, temporarily disable the security on each SSID and have a client associate. Taking security weirdness and complication out of the picture will allow you to confirm that your back end "plumbing" is all as it should be. Once that's confirmed, put your security back on.
As far as "spotty" is concerned, the only way to know what's going on there would be to do a site survey, and possibly have someone come bring a Cisco Spectrum Expert card to the site to check for interference.
Sincerely,
Rollin Kibbe
Network Management Systems Team
