[Babel-users] Fwd: Why we switched to Babel

[Juliusz Chroboczek]

Hi Saverio, long time no hear.  Pity you're not here.

> So why they switched to babel ?
> babel makes some magic with MTU ?

Nope.

The way I understand it, they had trouble with BATMAN's encapsulation in
a heterogeneous network (were it is difficult or impossible to increase
the link-layer MTU to 1532).

Recall that:

 1. BATMAN adds 32 octets of overhead to every frame;
 2. BATMAN requires the same MTU on all segments.

The result is that if you have just one segment that cannot increase the
link-layer MTU beyond 1500, you need to run your mesh with a network-layer
MTU of 1468.  Apparently that is the situation they found themselves in,
and were unable to get it to work reliably.

From what I gather, they're a community with unusual needs (strong emphasis
on decentralision and privacy, heterogeneous hardware, diverse userbase,
etc.), they're probably run into some snags with Babel too.  Which should
be interesting, and likely to improve Babel.

Time to do some testing, see you later.

-- Juliusz