Header format in monitor mode

Hector Velayos hvelayos
Wed Nov 26 07:58:18 PST 2003

Hello all,

I am capturing wireless LAN frames using the packet socket interface and the
monitor mode. The file hostap_wlan.h specifies three possible headers for
such frames:

	struct hfa384x_rx_frame
	struct linux_wlan_ng_prism_hdr
	struct linux_wlan_ng_cap_hdr

The hostap driver delivers the frames with the first header executing:

	iwconfig wlan0 mode monitor

Two commands are necessary to get the frames with the second header:

	iwconfig wlan0 mode monitor
	iwpriv wlan0 monitor 3

(Note that the second is deprecated, does anybody know an alternative

The question is: how can I get the frames with the third header?

I am interested in the third type of header because it features a higher
resolution MAC time (64 bits). This is very convenient for positioning
systems based in time difference of arrival.

Cheers, Hector

KTH IMIT - Forum building - 164 40 KISTA - SWEDEN
Tel: +46 8 7904256 Fax: +46 8 752 12 40

More information about the Hostap mailing list