WIFI连接建立过程

WIFI建立过程概述：

STA ------------> Probe Request   ----------------> AP //广播自身数据

STA <------------ Probe Response   <------------- AP

STA ------------>     Authentication Request --------> AP //认证Auth类型，Open System , Shared Key等

STA ------------>     Authentication Response------> AP

STA------------->    Association Request  ------------> AP  //请求与AP建立关联，从而可以进行数据交互

STA------------->    Association Response-----------> AP   

                                WEP/WPA/WPA2/DISABLED Security Type.

Data Communication

http://standards.ieee.org/about/get/802/802.11.html