On Fri, 2006-14-04 at 13:01 -0500, Mike McCarty wrote:
> Anne Wilson wrote:
> > On Friday 14 April 2006 15:47, Mike McCarty wrote:
> >
> > Your choice entirely. Encryption does work, and I also have checked that
> > nothing is detectable outside my boundaries. Then of course it can be tied
> > to mac addresses. It's perfectly possible to have the facility without risk.
> > If you don't need it, fine.
>
> Any machine to which there is physical access has only
> relative security. The fewer physical access points there
> are the higher the relative security can be. Removing the
> antenna almost removes one of the access points.
>
> I say almost because, should the firmware or hardware not
> properly disable the wireless I/F, someone who knew I was
> here and had a high-power transmitter and a focussed high
> gain antenna with a sensitive receiver could still get
> access.
>
Very true. Removing the antenna may not actually do what
you want, it will certainly reduce the antenna gain, but
does not prevent transmission or reception. What you
should do is install a 50 Ohm shielded terminator. You
will need a BNC adaptor for you antenna connector, which
could be a a TNC, SMA, Reverse TNC, Reverse SMA or other
similar type connector. You should bring your antenna
with you to make sure you get the right one. You can
likely get the adaptor and terminator at an electronics
supply store, or from a radio system installer.
We used to do a lot of wireless connections and determined
that even heavily shielded radios could communicate
effectively over a couple feet with no antennae installed
on either one. We also determined that using 100mW TX
power and 6 foot solid parabolic dishes they could
communicate reliably upto 40 miles between 200 foot
towers. It would be reasonable to interpolate that with
a 20 inch parabolic antenna at one end and no antenna
at the other end, you could reliable connect over a few
dozen feet {power is dissipated using an inverse square
law}. Using a high quality receiver and flat panel antenna
arrays it could be possible to receive a signal covertly
from hundreds of feet away, but then you don't necessarily
need a wireless router to do that anyway.;^) If you are
interested, there are a few good articles about Tempest
surveillance that are enlightening. I used to work on
anti-tempest compliant devices for law enforcement and
military applications, back in the late 80's. I can only
imagine how much better the new tempest stuff is. :^O
