[115367] in North American Network Operators' Group
RE: Wireless bridge
daemon@ATHENA.MIT.EDU (Lyndon Nerenberg)
Thu Jun 18 12:12:28 2009
From: Lyndon Nerenberg <lyndon@orthanc.ca>
To: Peter Boone <NANOG@Aquillar.com>
In-Reply-To: <09ef01c9f02d$221f21f0$665d65d0$@com>
Date: Thu, 18 Jun 2009 10:11:02 -0600
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Thu, 2009-06-18 at 11:54 -0400, Peter Boone wrote:
> Oh I know. Luckily it's located in an industrial area just on the
> outskirts
> of the city. There isn't a lot of other WiFi (in my opinion); 3-5
> total
> SSIDs spread across 2 of the 3 physical channels (1,6,11) depending on
> which
> rooftop you measure from.
2.4 and 5GHz license-free Wifi is license free because the frequencies
are shared with the ISM (Industrial/Scientific/Medical) services. In an
industrial area, competing WiFi is the least of your worries. These
frequencies are also used by industrial grade heating units. Got anyone
in the neighbourhood running a large plastic shrink wrap machine, for
example?
You can't directly detect these other users with a Wifi transceiver.
Depending on the nature of the interference you *might* be able to hear
it directly on a scanner (if you can find one that covers those
frequencies), but you really need a good spectrum analyzer to tell
what's going on.
Anyway, don't assume the competition for spectrum is only other Wifi
units.
--lyndon
