Why is it that tcpdump cannot monitor the 802.11n packets.
I am able to monitor packets in the 11b and 11g networks
Only 11n network is not possible. What could be the reason?

The wireless adapter supports 11n standards (checked packet capture using the tool OmniPeek in Windows platform )

I want to know why tcpdump cant capture 11n packets in Linux
Am currently using Ubuntu 12.04

Awaiting reply

I have a Linksys WUSB600N v1 [Ralink RT2870] adapter.
I am able to capture packets from 11b and 11g networks but not able to capture packets from 11n networks.(capturing using the Linux command tcpdump ). Should i configure the adapter or change some settings so that i can capture packets in the 11n network also? Or is the capture not possible due to some driver related issues?


Please reply

Some wifi driver requist to add monitor interface to capture packet.

how do i do that? do u know?

iw phy phy0 interface add moni0 type monitor
ifconfig moni0 up
ifconfig moni0 10.0.0.1 netmask 255.255.255.0
tcpdump -i moni0

Thank you very much

Btw i hav one more doubt

how will i GET the correct channel has been set using command
iw phy phy0 set channel 11 HT20 ?

and what is the use of the command

iw dev wlan0 set channel 11 HT20 when there is another command
iwconfig wlan0 channel 11

Should use iw dev wlan0 set channel 1 [HT20|HT40+|HT40-] to set channel or iw dev wlan0 set freq 2412 [HT20|HT40+|HT40-] to set frequency.

thank you

Btw could you also tell me on how to set the source MAC addr also using iw command
The problem is that iw only accept broadcast signals (am using my adapter in monitor mode )
Hence to use as a sniffer i need to set the MAC address (i tried setting the source MAC address from tcpdump but no capture occurs when i use iw
But capturing is possible when i set the modes using iwconfig

Awaiting reply

ifconfig wlan0 down hw ether 00:00:00:00:00:01
ifconfig wlan0 up

Thank you very much