Resolution
At this time, it is not possible to block the client access prior to the authentication request phase. All initial authorization blocking, still allows non-standard clients to broadcast requests to the access point (AP) which will bog the AP down with unwanted request attempts. The AP will still have to receive and accept the initial attempt by the unwanted clients to register, and will have to fail the request attempt.
Till now the AP is not smart enough to ignore or filter these request. You can disable SSID being broadcast . But this is also cracked when client sends the probe request as SSID is sent in the probe request.
Problem Type
Release notes / product overview / data sheet / FAQ
Technical product specification / features
Configure / Configuration issues
Products
WLAN adapters (wireless card) / ACU (Aironet Client Utility)
Access point
Topology
Wireless client to AP