Re: [babel] info-model: link properties

Juliusz Chroboczek <jch@irif.fr> Fri, 26 April 2019 10:21 UTC

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Date: Fri, 26 Apr 2019 12:21:00 +0200
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From: Juliusz Chroboczek <jch@irif.fr>
To: "STARK, BARBARA H" <bs7652@att.com>
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Subject: Re: [babel] info-model: link properties
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> Change registry items to
> other: no link property information available
> tunnel: a tunneled interface over unknown physical link
> wired: 
> wireless:

That is not my understanding of what we agreed to.

I was under the impression that we had decided that the classification of
link types in wired/wireless/tunnel is an internal implementation detail
of babeld, and that what we wanted to export were the underlying
properties, which are:

  - link cost estimator (ETX or 2-out-of-3);
  - use split-horizon (boolean);
  - use RTT (boolean).

wired means 2-out-of-3, split-horizon, no RTT.
wireless means ETX, no split-horizon, no RTT.
tunnel means 2-out-of-3, split-horizon, RTT.

It is clear to me that the interface type abstration is useful for the
user, who doesn't want to deal with technical details such as whether the
split-horizon optimisation is allowable on a given link type, but it's
difficult to export from the management interface.

-- Juliusz