Rich Freeman on 29 Jan 2011 15:14:57 -0800

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Re: [PLUG] Can wifi mesh networks make up for Internet Service non-Providers

On Sat, Jan 29, 2011 at 9:19 AM, Matt Berlin <> wrote:
> I've been thinking about this.  I suppose no one thinks of it until
> it's too late.
> Let's not be too late here.

I'm not sure mesh networks will ever take off until the supply of
bandwidth greatly exceeds the demand.

Mesh networks tend not to be as efficient as direct networks, and
direct networks aren't that expensive.  That means that most people
will be content to stick with traditional ISPs.  Sure, the mesh is
more resistant to disruption, but few will install a network "just in
case" big brother takes over.

Mesh networks are pretty good for the last mile, but as distance
increases they tend to saturate since the pipes aren't big.  You need
to get data off the mesh onto cables quickly for it to work.  Those
cables of course are easily intercepted.

Plus, if you think about geography you might have a huge mesh all
over, say, the Philadelphia Metro.  However, after some distance
population density drops and you just have strings of tiny towns along
major highways.  If you stick a jammer on a few of those highways you
cut off an entire city.

Most mesh network technology is also not built with intentional
jamming in mind.  The dinky transmitters in your Linksys router aren't
going to stand up when somebody just dumps 10MW of RF in the 2.4GHz
range.  A jammer could take out nodes for miles around.  You need a
lot more nodes than jammers, and jammers aren't that expensive to
build.  Because of natural corridors the jammers need not have
ubiquitous coverage either.

Now, for OLPC or something a mesh makes sense.  You are going to
transmit email and stuff - not HDTV - and jamming won't be an issue
(intentional or otherwise).  You can also easily put in uplinks in
each village or whatever when they aren't dense enough for the mesh to
propagate, assuming that long-distance communication is even needed.
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