[Roll] RPL convergence behavior (was: Way forward for draft-clausen-lln-rpl-experiences)

Richard Kelsey <richard.kelsey@ember.com> Wed, 16 May 2012 15:43 UTC

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To: Thomas Heide Clausen <ietf@thomasclausen.org>
In-Reply-To: <0AA713FC-2C91-41E4-80BF-3DA3FF450324@thomasclausen.org> (message from Thomas Heide Clausen on Wed, 16 May 2012 17:08:10 +0200)
From: Richard Kelsey <richard.kelsey@ember.com>
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References: <258D7E2F-F0C7-49EA-B831-81070C86EDB3@thomasclausen.org> <2257A578-B2DF-4145-8393-9BB5D7E1CFBD@cisco.com> <2225986E-992E-43C7-B0CA-9CDA91CE1F3A@thomasclausen.org> <B1B81482-0F7E-4BCE-BBA7-B21949E3C16C@cisco.com> <22B18A3C-B327-4AD6-9D94-901CF225BE98@watteco.com> <0AA713FC-2C91-41E4-80BF-3DA3FF450324@thomasclausen.org>
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Cc: roll@ietf.org, mcr@sandelman.ca
Subject: [Roll] RPL convergence behavior (was: Way forward for draft-clausen-lln-rpl-experiences)
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> From: Thomas Heide Clausen <ietf@thomasclausen.org>
> Date: Wed, 16 May 2012 17:08:10 +0200
> Again, the observations that we present in this I-D make
> exclusive reference to RPL, and not to a specific
> implementation or deployment.

While this is largely true, some of the observations are
based on experiments, and in those cases the details matter.
>From the draft:

   13.1.  Observations

   The varying link quality in real-world environments results in
   frequent changes of the best parent, which triggers a reset of the
   Trickle timer and thus the emission of DIOs.  Therefore Trickle does
   not converge as well for links that are fluctuating in quality as in

A link is neither good nor bad but thinking makes it so.  What
sort of links were you using?  How did you measure link quality?
Different techniques have given very different results.

                                    -Richard Kelsey