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Bill Kearney Bill Kearney is offline
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First recorded activity by BoatBanter: Dec 2006
Posts: 223
Default Wireless Internet while Cruising

Netstumbler was very useful on Exuma for finding signals. Found 3 usable
signals at Georgetown with weird radiation patterns. 200 yards made a lot
of difference in signal strength. Also at the Four Seasons Marina,

Emerald
Bay, Staniel Cay and Cat Island.

Marina wifi antennas are aimed out over the slips and tend to fall off
rapidly near the edges of the pattern. If you can find the center of the
pattern you can be a fair ways off and still get a usable signal. The
problem with marina systems is that you have to go in and open an account
which cost a few bucks if you are not in a slip. A lot of villas along

the
beach have unsecured APs too and they have very erratic patterns. Must
have something to do with the position of the AP to windows and metal in

the
house. With a good wifi rig you can sometimes find them several hundred
yards off shore.

Coverage is hit and miss but with the right tools you can sniff out more
spots.


Excellent report Glenn. That's why having a tool like NetStumbler is
useful. The normal built-in wifi software doesn't usually give you signal
strength meters. And the few that do usually don't have a rolling log of
it. With stumbler you get a bar chart showing you the signal strengths of
all the networks it could see, logged for as long as you have stumbler
active. So you can fire up stumbler and use it to hunt around a bit looking
for a good signal.

You're also right about the windows and metal. Many modern windows have a
coating (either for UV or tint) that seems quite effective at blocking wifi
signals. That and the wire put up behind most stucco also serves as a
rudimentary Faraday cage also blocking signals.

If you REALLY want to geek out and see more detailed wifi info then get a
linux boot CD with a program called kismet on it. kismet is like stumbler
on steroids. But it's overkill for most folks.

-Bill Kearney