Re: [B.A.T.M.A.N.] Migration to Batman

Marek Lindner
2012-04-16T10:37:36Z

On Monday, April 16, 2012 12:25:42 Mitar wrote:
> I have problems with an idea of running another routing protocol on
> top of Batman. I think this is creates unnecessary additional
> bandwidth consumption:
> 1) routing protocol has to find which nodes are reachable
> 2) routing protocol has to exchange information about announced routes
>
> But 1) Batman already knows. So we could have a netlink protocol where
> user-land daemon could subscribe to events and get for example two
> events: "node reachable" and "node unreachable". Then it can do some
> user-land mingling. :-)

Batman-adv already has an event reporting system (via sysfs):
http://www.open-mesh.org/wiki/batman-adv/Uevent
It could be easily extended to also throw node events (reachable/unreachable).

Note: Whoever is going to implement that should think about the implications
of mesh clouds periodically connecting and disconnecting. A lot of events
could be fired over and over again.

> And for 2), Batman could allow a general key/value additional
> information to be announced by nodes. From its point of view that
> information can be anything.
>
> And the in our case we could add to each node information which IP it
> has and which subnets it has behind. This information would then be
> announced to other nodes. And then we could run a simple daemon on
> other nodes which would listen to netlink events and once a node is
> reachable, read that information and setup necessary routes.

There is no need to implement such a thing in batman-adv. You can have this
feature today by using any broadcast system (avahi, routing daemon, self-
implemented thingy, etc) you like. Here also lies the misunderstanding: You
don't need to run another routing protocol "on top" of batman-adv. You only
run it to announce "stuff". You can simply run your routing protocol of choice
to announce the routes.
This was explained several times in this thread - maybe it still is not clear?

Cheers,
Marek