Hams Report 85-mile 802.11b File Transfers @ Oregon

Scott Weikart scott at igc.org
Wed Apr 14 18:20:28 PDT 2004


On Wednesday 14 April 2004  6:08 pm, richard childers / kg6hac wrote:
> Put another way, the area equals pi times the radius, squared ... so the
> number of people who have the theoretical opportunity to passively crack
> your wireless network increases, dramatically, with each increment of
> distance from the center.

True.

> You can pack an awful lot of people into a circle with a radius of 85 miles
> ... that's 170 miles, diametrically.

Probably irrelevant.

We're still presuming that 85 miles only worked because two
directional antennas were aimed at each other.

When you're trying to snoop a mostly-omnidirectional antenna, your
relevant radius is much smaller.

[NOTE: I still wouldn't advocate that anyone rely on WEP, and I'm
not sure LEAP can be relied on either; and WPA needs good keys.]

-scott

> >On Wed, Apr 14, 2004 at 01:05:04PM -0700, Scott Weikart wrote:
> >
> >Well, I recently tried an old 25" satellite dish and a biquad feeder
> >and we easily 'saw' APs at 3-4 miles away.  Without trying anything fancy.
> >You need line of sight to the AP in most cases.  Hills help.
> >
> >>I would assume the hams used directional antennas on both ends, and
> >>carefully pointed the antennas at each other.
> >>
> >>So, this may have little relevance to monitoring people's
> >>mostly-omnidirectional wireless LANs.  Well, maybe you could so some
> >>math to make the ham's numbers scale, but I would guess there are
> >>more direct methods to measure/compute risk.
> >>
> >>-scott


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