Before a client can join a wireless network it must first authenticate and associate it’s identity with the AP. Now that we can easily capture wireless traffic with our Aerohive APs we decided to take an in depth look at the association to document what happens at the 802.11 packet level. This collection of captures show different client devices associating with our Aerohive Access Point.
In this capture the Asus device begins the association but during this process the Aerohive uses Dynamic Channel Switching and changes from using channel 6 to channel 11. Between the APs the Aerohive Channel Selection Protocol (ACSP) is used to select the channel that the APs will use.
In this example an incorrect WPA2 password is used. WPA/WPA2 and 802.1X authentication happen after the 802.11 Authentication and Association messages are exchanged. 802.11 Authentication frames were originally used with WEP securitty algorithms which have since been deprecated.
By default the Aeorohive supports 100 Maximum Clients per SSID. When the
configured number of clients have connected new association requests are
responded to with the status code
0x0011 indicating that the AP is unable to
handle additional clients.
These captures were performed using the Aerohive Connect AP250 Access Point.