[Commotion-discuss] networking/guidelines-for-mesh/

[Andy Gunn]

Hey Francis - thanks for writing back. Josh responded earlier, and I
agree with what he wrote - most of the "Guidelines for Mesh Networks"
document is geared towards reducing wireless interference. The mesh
specific parts are really about reducing the number of hops, and not
overloading wireless interfaces (using AP & mesh interfaces on one radio).

More discussion in-line with your questions below:

On 04/09/2015 07:41 PM, Francis X. Gentile wrote:
> 
> https://commotionwireless.net/docs/cck/networking/guidelines-for-mesh/
>
>  so if you are walking or driving from on smaller mesh another, on 
> separate channels, whose smaller meshes are connected by a long
> distance backbone which uses the Ubiquiti software (which has the
> channel hopping for 5ghz to access more channels, and the weak
> strong signal unbiased allocation).....
> 
> how does the mesh retain its identity and server access across a 
> different network (and thus ip address protocol) does the mesh
> software put itself in an envelope and pass along the alien network
> to stay cohesive at both ends?

Josh answered this as well, but yes, the mesh software can be
configured to route over other links, such as point-to-point (or even
Ethernet or fiber) links to bridge separate networks or parts of
networks together. So you can have several separate meshes communicate
and be linked together in this way.

> Or is the wide area mesh system abandoned , and the only remaining
> use for mesh is for at the fringes of reception from the back bone
> for another hop or two,
> 
> but using the unbiased weak strong signal allocation of the
> Ubiquity system, a longer distance 2 ghz router could be an access
> point for longer distances anyway?

Any wireless equipment can have issues with long-distance Access Point
links, as this is usually a limitation of a user's device. A
smartphone doesn't have as much power to transmit back to an AP, so
after a certain distance it's signal will be lost in the noise,
regardless of how sensitive the receiver is in the Access Point.

> If every user in the mesh is say, a fire truck among many
> traveling, or a bunch of RVs, or a climbing expedition, or driving
> mob of vehicles going to burning man, it this the only place mesh
> ad hoc mobile networks are really needed?  is a headless self
> reconfiguring network on one channel necessary?

I think such a mesh network is a great tool for community networks
that are small, or starting out and want an easier-to-use and
self-configuring system. The great thing about all the mesh systems
out there (caveat: I have only used qMp, LibreMesh, Commotion,
Ubiquiti's WDS system, and Merkai's "mesh" system) is that they are
generally quick to set up and relatively simple for the user.

When community networks start getting very big, or have lots of users,
then other wireless networking techniques are needed to keep
performance reasonable. That is why I wrote "Types of Wireless
Networks" - to give folks a starting point on learning about and
designing other systems to mix in with mesh and create larger systems.
https://commotionwireless.net/docs/cck/networking/types-of-wireless-networks/

> so is the deployment of non monopolisitic corporate local intranet
> or internet access being delayed by pointless machinations about
> mesh networking when you could just as well deploy stock wireless
> internet service provider equipment from Ubiquity et al?

I think that is a great question - but I think it comes down to
opinion. I can see it both ways - using established wireless
networking equipment and methods can lead to the same ends. In most
cases, the software that runs Ubiquiti and MikroTik and other such
wireless equipment isn't free / open source, so it comes down to the
philosophy of using free / open source software.

The decentralized nature of mesh networks also appeals to many people.
Since there is no center "hub" of the network, to more closely mirrors
the social relationships people want to see.

Some of the largest community wireless networks in the world
(Guifi.net for example) are hybrid systems - they use many different
routing protocols, types of hardware, and a mix of mesh and non-mesh
technologies.

So, I won't directly answer that question, and leave it up to
communities who want to build their own infrastructure and networks.

Thanks again and take care.
-Andy


-- 
Andy Gunn, Field Engineer
Open Technology Institute, New America
andygunn at opentechinstitute.org | 202-596-3484
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