Debian WPA Wireless how to use

# vi /etc/network/interfaces
auto eth1
iface eth1 inet dhcp
wpa-ssid [EESID]
wpa-psk [passowd key]
# ifup eth1

root@Lenovo-B480:/home/clementyan# ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_req=1 ttl=46 time=11.7 ms
64 bytes from 8.8.8.8: icmp_req=2 ttl=46 time=12.8 ms
64 bytes from 8.8.8.8: icmp_req=4 ttl=46 time=12.5 ms