  This paper considers on a network routing protocol known as Better Approach
to Mobile Ad hoc Networks (B.A.T.M.A.N.). The protocol serves two aims: first,
to discover all bidirectional links, and second, to identify the best-next-hop
for every other node in the network. A key element is that each node will flood
the network at regular intervals with so-called originator messages.
  This paper describes in detail a formalisation of the B.A.T.M.A.N. protocol.
This exercise revealed several ambiguities and inconsistencies in the RFC. We
developed two models. The first implements, if possible, a literal reading of
the RFC, while the second model tries to be closer to the underlying concepts.
The alternative model is in some places less restrictive, and rebroadcasts more
often when it helps route discovery, and will on the other hand drop more
messages that might interfere with the process.
  We verify for a basic untimed model that both interpretations ensure
loop-freedom, bidirectional link discovery, and route-discovery. We use
simulation of a timed model to compare the performance and found that both
models are comparable when it comes to the time and number of messages needed
for discovering routes. However, the alternative model identifies a
significantly lower number of suboptimal routes, and thus improves on the
literal interpretation of the RFC.
