[B.A.T.M.A.N.] link alternation when radios are not on batman-adv router?

Dan Denson dandenson at gmail.com
Sat Mar 31 17:45:21 CEST 2012

> batman-adv makes no difference between ethernet or radio interfaces,
> they are all simply just interfaces that somehow link to other
> batman-adv nodes (with some -or zero- packet loss)
> so link alternation would work the same: if packet comes in through
> radio, and batman-adv can reach the destination through the ethernet
> port (it doesn't matter if that implies hopping through more
> batman-adv nodes) it will prefer sending it through this "alternate"
> path (alternate in the sense it doesn't use the same interface the
> packet came in)

So how does hop count come into play or does it? Is it just the connection quality that is considered?

> A long thread earlier this month was particularly clarifying on the subject.
> https://lists.open-mesh.org/pipermail/b.a.t.m.a.n/2012-March/006351.html
Thanks, I'll check that out

> Yes. in addition you might also be interested in interface bonding,
> which is not enabled by default but can be activated after
> understanding a few caveats. it's documented on batctl manpage online.

I read up on bonding, I think that leaving the dynamic interface alternation is more ideal but I think I'll play with it.

> If picostations are only connected point-to-point to each other, and
> there are no other clients sending traffic to them (except the
> supernodes), then interface alternating won't take advantage of the
> "faster dual link connection"
> You must use interface bonding to achieve that.
> Interface alternating would be useful, for example, if picostation2
> from supernode2 was receiving a radio transmission from a distant
> supernode3 (not pictured) destined at supernode1. Then, instead of
> trying to relay the packets through that same picostation2, it would
> use picostation1 to send them and avoid reusing the same interface.
> Cheers!
> Guido

 I think I understand. Basically, so long as two interfaces both have a path the to destination of acceptable quality, it will send the packets out the interface that did not receive the packets. Hop count doesn't have a direct effect, we don't really care about hop count, only about link quality.

Is that the case?

If hop count doesn't really matter, how do I identify my high quality, high capacity backhauls?

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