[B.A.T.M.A.N.] No rebroadcast on mesh links

Roland Volkmann
2016-03-25T21:35:43Z

Hi,

when having Nodes with wired Mesh-Links, or on point-to-point
connections, rebroadcasts on the same interface are unnecessary, because
all Nodes receive the broadcast packets at the same time.

On non-gateway nodes (Freifunk-Routers) running firmware "Gluon", there
is a patch from Linus Lüssing adding the feature/option
"mesh_no_rebroadcast" to batman-adv, which is enabled by default on
mesh_vpn interface. Because of the good experience reducing traffic also
on other wired mesh links (Mesh-on-LAN / Mesh-on-WAN), this option will
also be enabled there by default with the upcoming Gluon v2016.2.

Gatways are not running Gluon, but typically Debian Linux, and there the
option "mesh_no_rebroadcast" does not exist on batban-adv.

Are there some (other) features already implemented in batman-adv to
prevent rebroadcast of unnecessary mesh packets?

If not, what is the chance to have the functionality implemented by the
mentioned patch as part of the original code base?

Background:

At Freifunk-Stuttgart we have multiple distributed gateways connected by
layer2-tinc, which is logically the same situation as using LAN-Cables
and physical Switch. Avoiding rebroadcast will reduce traffic between
the gateways.

Additional info:

On 12.03.2015 Ticket #207 was opened by Ruben Kelevra relating the same
issue, but immediately closed due to formal error.

Best regards,
Roland.