[Babel-users] [babel] Babel to standard

[Juliusz Chroboczek]

I've reordered your comments.

> I would say each proposed extension needs a pretty clear use case,
> a specification, and then an implementation report (if available), and
> possibly some form of deployment experience draft (if available).

That's not the way we work, here at Babel Towers.  We don't usually
develop an extension without an actual feature request from our users, and
we never freeze the protocol until we have both working code and
deployment experience.  We're very serious about that.

> A protocol version? It would be simpler to have some sort of capabilities
> negotiation here, possibly.

That's not how Babel works.  A Babel router simply ignores any routes it
doesn't grok.  In other words, capability negotiation happens at route
granularity, not at neighbour relationship granularity.

> Note that choosing a route across two metrics is, as I understand it,
> unsolvable. This is the reason EIGRP uses the K values to merge the
> metrics

A given router must use a single metric (at least in the absence of
TOS-specific routing and similar), granted, but distinct routers may use
different metrics.  This is analogous to routing policies in BGP.

> Note also there needs to be some way to prevent oscillation between the
> control plane and the data plane when you start playing with delay,
> bandwidth utilization, etc., in the real world. These are nasty
> problems.

Absolutely.  We have worked really hard on stability, this is described in
detail in

   Baptiste Jonglez, Matthieu Boutier (PPS), Juliusz Chroboczek.
   A delay-based routing metric.  Unpublished draft.  2014.
   http://arxiv.org/pdf/1403.3488

-- Juliusz