Monitor mode without association

Jouni Malinen jkmaline
Fri Nov 15 22:39:32 PST 2002

On Fri, Nov 15, 2002 at 11:26:12AM -0500, Bichot Guillaume (Princeton) wrote:

> ( In the HOST side, I switched from Managed to Monitor mode.)
> Does the driver monitor the channel corresponding to the ESSID and/or the
> frequency/channel (delivered through iwconfig)?

Frequency/channel (contents of the frames, including BSSID, is ignored)

> Does the monitor mode preclude the host to associate with the access point
> corresponding to the ESSID and/or the frequency/channel (delivered through
> iwconfig)?

Monitor mode is a test mode and its behavior is not fully described (and
might even change based on firmware version). It seems to stop lot of
normal station functionality and I would assume that association would
not be completed while in monitor mode.

> Before the last hostap_release (2002-10-12) the monitor mode seem to
> preclude association between the host and the AP (that is what I'm looking
> for by the way). The host was really passive.
> With last release (2002-10-12), the host can still send and receive packets
> in monitor mode meaning the host seems associated with the AP.

I don't remember changing anything related to this in 2002-10-12

> What I'm really target is a host being able to listen only (no uplink
> traffic at all) a particular channel.

Monitor mode would then be your best choice with Prism2 cards. If you
want to make sure there is not traffic at all, you could also disable TX
from baseband processor.

Jouni Malinen                                            PGP id EFC895FA

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