Wireless network source

Is there a way to find out or approximate the location of a particular
wireless (wifi) peer/client?

(E-Mail Removed) wrote:
>Is there a way to find out or approximate the location of a particular
>wireless (wifi) peer/client?

You can do the usual direction-finding thing, though with reflections
and multipath it can get really nasty quickly. One method that seems
to work is plotting signal strength while moving around the area of
the suspected peer and generating a map.

On Fri, 16 Jun 2006 08:51:17 -0400, William P.N. Smith
<(E-Mail Removed)> wrote in
<(E-Mail Removed)>:

>(E-Mail Removed) wrote:
>>Is there a way to find out or approximate the location of a particular
>>wireless (wifi) peer/client?
>
>You can do the usual direction-finding thing, though with reflections
>and multipath it can get really nasty quickly. One method that seems
>to work is plotting signal strength while moving around the area of
>the suspected peer and generating a map.

It really helps to have a highly directional antenna.

--
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(E-Mail Removed) hath wroth:

>Is there a way to find out or approximate the location of a particular
>wireless (wifi) peer/client?

Yes, but it's no fun. I've done it a few times.

First you need a sniffer program that will see client radios.
Netstumbler won't do that. You'll need Kismet for Linux. This is
best run from one of the LiveCD distributions. No need to reformat
your laptop hard disk.
http://www.remote-exploit.org/index.php/Auditor_main

Next, you'll need a supported wireless card with an external antenna
connector. There are some PCMCIA cards that have connectors, but
methinks the USB radios with the flip up antennas are probably a good
substitute. The radio will need to be shielded, the antenna removed,
and a connector attached.
http://www.remote-exploit.org/index....itor_dev_list1

Next, you'll need a directional antenna. This part is critical as any
side lobes are guaranteed to cause difficulties in determining the
direction. A commerical dish antenna is usually best. 24dBi is too
big to handle easily. I use the 19dBi size. I found the typical
barbeque grill antenna leaks a bit out the back, so I just covered the
dish with aluminum foil. An 18" DBS pizza dish does NOT work well.

You'll need some practice using this affair. The correct way is to
use a map. Orient the map in the proper compass direction and draw a
line through your known location to the direction where the signal is
coming from. Then, move approximately perpendicular to this line and
draw another line. Do as many lines as practical. Many of these will
miss horribly because of reflections. Where the majority of the lines
intersect is the culprit.

Direction finding tends to break down when you get close to the signal
source. You may need a coaxial attenuator between the antenna and the
receiver to prevent overload. This also where receiver shielding
becomes important.

Good luck.

--
Jeff Liebermann (E-Mail Removed)
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558