[Babel-users] Should I use wifi mesh routing in crisis situations?

[Mitar]

Hi!

I would also be surprised if 802.11s works better than ad-hoc. I think
it is just a question of configuration in both cases. It is really
primarily limitation of one-channel communication.

Maybe through years ad-hoc implementations got bugs, but few years ago
ad-hoc mesh worked OK with wlan slovenia firmware. (With OK I mean 1
Mbit/s speeds. One YouTube video and this is it.) Maybe we just got
used to N and AC speeds and this is now not enough. I would guess that
all MIMO and package pipelining done with N and AC protocols do not
work well in ad-hoc mode.

One thing with one-channel mesh networks one has to consider is how
much noise each node is making to other nodes. You probably want to
sometimes even make TX power smaller to make less noise to other
nodes.

But ad-hoc mode was never really meant for performance but for
independence to me. That the mesh network operates even without
uplinks and tunnels. And then speed one gets with backbone links.

So maybe think about setup where you use multiple radios per device.
Using ad-hoc, 802.11s, or 802.11s with one hop (nice trick, btw), I do
not think it matters so much. But test it. Test it also with different
TX powers. I think you should understand that 802.11s will not scale.
So really use it just for small parts of the network, you then combine
with L3 routing protocol together.


Mitar

On Thu, Jun 22, 2017 at 3:19 PM, Valent Turkovic
<valent at otvorenamreza.org> wrote:
> On Thu, Jun 22, 2017 at 6:20 PM, Juliusz Chroboczek <jch at irif.fr> wrote:
>>>>   1. ad-hoc mode doesn't work as well as infrastructure mode;
>>
>>> Has anyone tries using 802.11s configured interface?
>>
>> Interesting idea.  I'd be surprised if it worked much better than plain
>> ad-hoc mode, but I'd love to be proved wrong.
>>
>
> I had really bad experience with adhoc mode, so I'm willing to try
> 802.11s and my feeling is that nothing can be as bad as adhoc.
>
> Friend just shared this great discussion from 2014:
> http://lists.alioth.debian.org/pipermail/babel-users/2014-November/001786.html
>
> This gives quite a nice background explanation, so thank you Juliusz
> from the past :)
>
> What I'm trying to find from this mailing list? Just not to repeat
> tests that others have done, and of others have some best practices to
> share them.
>
> But if nobody has compared babel on adhoc and 802.11s routers then my
> team and I'll do this test and report back.
>
>>>> If you're using diversity routing (Babel-Z), be
>>>> aware that current versions of babeld are unable to automatically
>>>> determine the channel number of interfaces in AP mode -- you'll need to
>>>> set them manually.
>>
>>> We are using wlan-slovenia firmware, and AFAIK this is regular babel.
>>> I'll read up on babel-z.
>>
>> It's included in the babeld binary.  Just add "diversity true" to the
>> config file.
>>
>> The protocol is described here:
>>
>>   https://tools.ietf.org/html/draft-chroboczek-babel-diversity-routing
>
> Thanks, I'll look into this.
>
> _______________________________________________
> Babel-users mailing list
> Babel-users at lists.alioth.debian.org
> http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/babel-users



-- 
http://mitar.tnode.com/
https://twitter.com/mitar_m