Re: [babel] [Babel-users] About Babel-RTT

Juliusz Chroboczek <jch@irif.fr> Tue, 28 July 2020 17:55 UTC

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Date: Tue, 28 Jul 2020 19:54:30 +0200
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From: Juliusz Chroboczek <jch@irif.fr>
To: David Schinazi <dschinazi.ietf@gmail.com>
Cc: Babel at IETF <babel@ietf.org>, babel-users <babel-users@lists.alioth.debian.org>, "Velt, R. (Ronald) in 't" <Ronald.intVelt@tno.nl>
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Subject: Re: [babel] [Babel-users] About Babel-RTT
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> I'll note that while a theoretical explanation/study sounds interesting,
> it's not required for publication of an IETF document.

In my opinion, without a theoretical understanding, it is difficult to
provide adequate guidance to implementers.

We have a deep theoretical understanding of what makes Babel work.  This
is why we can say with confidence that implementations MUST evaluate the
feasibility condition and that the metric MUST be stricly monotonic, but
we can safely leave the details of the route selection algorithm to the
implementation.

Not so with Babel-RTT.  We've got an implementation that has been shown to
work, but we have no precise ide which parts of the implementation are
important and which are coincidental.  In this situation, I don't feel
confident to write up a protocol description.

-- Juliusz