[PATCH RFC 1/1] Add the Babel routing protocol (RFC 6129) to Bird.

Alex Bligh alex at alex.org.uk
Tue Aug 25 21:05:11 CEST 2015

On 25 Aug 2015, at 19:34, Juliusz Chroboczek <jch at pps.univ-paris-diderot.fr> wrote:

> Yes.  Babel is designed to be robust not only on wired networks (where
> OSPF and IS-IS work just fine), but also on wireless mesh networks, where
> a routing loop, even a transient one, causes cross-link interference and
> may prevent the routing protocol from reconverging.  For that reason,
> Babel prefers to blackhole rather than risking to create a routing loop.


For my own education, why blackhole the route rather than simply not
propagate it at all to the FIB (i.e. ignore it)? Is the aim here to
avoid the consequent ICMP unreachable packets closing TCP sessions
during reconvergence? How should the blackhole route interact with
other routing protocols?

Alex Bligh

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