[Babel-users] First test of babelz at WBMv3.1416

Benjamin Henrion bh at udev.org
Fri Sep 10 08:37:24 UTC 2010


Just to write you a quick report of the babelz test we made at WBM3.1416.

1. Ivo made OpenWRT (Backfire) package for Babelz, which is available here:


We installed it successfully on 8 foneras running backfire.

Please mirror before it disappears.

2. We made some tests with 4 pairs of foneras (8 routers total)
connected with an ethernet cable in between, one fonera on ch1 and the
other one on ch13 (radio was at 1dbm 1mbits)
3. Babelz was running with the option -z 2,30 on both wlan0 and eth0
4. We got pretty stable results by distancing the nodes, and the route
was the correct one, hoping from one channel to the other, offering 0%
packet loss.
5. We did not had time to test the throughput, since we had a problem
of doing more then 4 hops, since the 4 node was always associating
with the second one (with packet loss)
6. The last hop between node 3 and node 4 was still hoping over the
same radio, because the other radio was misconfigured (the node
refused to put itself on ch13 due to regulation domain I suppose)

Wishes: we would like to patch the current Babelz to forbid the
routing protocol to hop over the same channel.

We gonna organise another WBM V3.5 in Charleroi in November (Charleroi
has cheap flights with Ryanair).

I am also looking for people with a bit of time to setup an OpenVZ
with several containers which would export a wlanX interface from the

That would help to see how the babel daemon reacts in a simulated environnement.

Another idea is to use iptables to force some routes when some nodes
sees at other. But that should not normally happen of the routing
daemon chooses the fastest path, not the shortest one.


Benjamin Henrion <bhenrion at ffii.org>
FFII Brussels - +32-484-566109 - +32-2-4148403
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