CentOS 6.8 Wifi

1) Offline
$wpa_passphrase "NetworkName" Key

#wpa_supplicant -B -D wext -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant_vicg.conf
#ifup wlan0

#vi /etc/wpa_supplicant/wpa_supplicant.conf
ctrl_interface=/var/run/wpa_supplicant
ctrl_interface_group=wheel
network={
    ssid="NetworkName"
    scan_ssid=1
    key_mgmt=WPA-PSK
    psk=??????
}


2) GUI Assistant
sudo vi /etc/sysconfig/network-scripts/ifcfg-wlan0

Resources:
[1] Enable Wifi https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux_OpenStack_Platform/3/html/Installation_and_Configuration_Guide/Disabling_Network_Manager.html