RE: [Aironet] Re: aironet iwlist help

[Peter K. L. <sa...@el...>]

Well, I think usually what happens when a client wants to connect to an 
AP, is that it sends out a probe request (management frame subtype), and 
depending on which access point responds first, or which access point 
meets the criterion, the client then chooses which access point to 
associate with.  
Also, I'm thinking you mean crossing over to other access points when you 
talk about "handoff", that is usually done by the client prior to 
disassociating with the current access point, which is determined when the 
client receives a response from an access point that has better parameters 
than the existing one.  (The client periodically checks to make sure it 
has the best connection at all times).
Notice none of these requires the client(driver) to be in rfmon mode.

-Peter


On Mon, 17 Dec 2001, Ali Mohammed-MALI1 wrote:

> Thanks, for all the help, Following up on our discussion below. I am curious about how the driver has information about the neighboring access points and how does it do handoffs without switchin into rfmon mode?
> 
> Mohammed 
> 
> -----Original Message-----
> From: Peter K. Lee [mailto:pk...@du...]
> Sent: Thursday, December 13, 2001 1:01 AM
> To: Ali Mohammed-MALI1
> Cc: sa...@el...; Aironet mailing list
> Subject: Re: [Aironet] Re: aironet iwlist help
> 
> 
> No, I do not think it is possible to stay associated and still put the 
> card into rfmon mode.  I'm not sure if its problem with firmware not 
> supporting this, but there has been some work trying to support 
> transmission of frames while still in rfmon (I think), but I'm not sure 
> where that's going yet.
> 
> Perhaps there are others that know more about this?
> 
> -Peter
> 
> 
> Ali Mohammed-MALI1 wrote:
> 
> >>well, you're in luck :)  If you run aironet driver is promisc. mode, or 
> >>prism2 driver in promisc. mode, you can get a list of access points in 
> >>your range.  All it does is listen to management beacon frames and based 
> >>on channel info, it constructs a list of access points that you can "see".
> >>
> > 
> > Thanks for all the help :). I will look into AirTraf. However, I need to
> > clarify if you are referring to promisc mode as "rfmon" mode. Isn't it true
> > that we cant transmit data when we are in monitor mode. Is there a way i can
> > dynamically switch in and out of monitor and associate mode without loosing
> > the association?. My intent is to do some pre-registration for L3 handoff's
> > based on L2 trigger and for this i need the interface up all the time and be
> > able to get a list of potential access points to associate with on the same
> > channel. I understand this can be done with a dual interface approach, is
> > there any other way we can achieve this with a single interface ?
> > 
> > 
> > Thanks,
> > Mohammed
> > 
> > 
> > Jean Tourrilhes wrote:
> > 
> > 
> >>On Wed, Dec 12, 2001 at 07:51:25PM -0600, Ali Mohammed-MALI1 wrote:
> >>
> >>
> >>>Hi Jean,
> >>>
> >>>Pretty impressive collection of wireless tools.
> >>>
> >>>
> >>	Thanks ;-)
> >>
> >>
> >>
> >>>I downloaded the version 20 of the wireless tools and i am trying to
> >>>use iwlist to get the list of neighboring ap's in range.
> >>>
> >>>
> >>	I must admit that the current API for APLIST in the Wireless
> >>Extensions is quite broken. When I designed it, way back in the
> >>prehistorical age of Wireless LANs, I didn't really had a clue how
> >>this would evolve.
> >>	The good news is that I'm in the process of fixing the
> >>Wireless Extensions for that. The bad news is that it will take a bit
> >>of time before you see it working in your favorite driver.
> >>
> >>	In the meantime, I would recommend either to use the private
> >>API of the driver or sniffing tools. Please ask competent people on
> >>the Aironet mailing list (cc'ed).
> >>
> >>
> >>
> >>>This list only  has the entry for the AP that i
> >>>am currently associated with. How about other ap' out there. What do i
> >>>
> > need
> > 
> >>>to do to see them on the list? How is this list acquired is it through the
> >>>ap you are bridging( from the ethernet)? or on the radio channel?
> >>>
> >>>
> >>	Most often, scanning is limited by default only to APs with
> >>the same ESSID as yours. Check with the folks on the mailing list for
> >>exact details.
> >>
> >>
> >>
> >>>Is there some other way i can get the list of AP's on the radio channel?
> >>>
> >>>Any help would be greatly appreciated.
> >>>
> >>>Thanks,
> >>>Mohammed 
> >>>
> >>>
> >>	Good luck...
> >>
> >>	Jean
> >>_______________________________________________
> >>Aironet mailing list  -  Ai...@cs...
> >>http://csl.cse.ucsc.edu/mailman/listinfo/aironet
> >>
> >>
> >>
> >>
> > 
> > _______________________________________________
> > Aironet mailing list  -  Ai...@cs...
> > http://csl.cse.ucsc.edu/mailman/listinfo/aironet
> > 
> > 
> > 
>