Re: [Roll] knowing which multiple metrics matter: MRHOF related questions

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 25 May 2012 19:29 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: "Pascal Thubert (pthubert)" <pthubert@cisco.com>
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Date: Fri, 25 May 2012 15:29:49 -0400
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Subject: Re: [Roll] knowing which multiple metrics matter: MRHOF related questions
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>>>>> "Pascal" == Pascal Thubert <(pthubert)" <pthubert@cisco.com>> writes:
    Pascal> I think RPL does not want to take party there. The OF is a
    Pascal> piece of logic to tie metrics and policies together.  

My question is:

- do the nodes of a DODAG have to use the same metrics to pick a parent,
  (and if so, how do they agree)
  I think that they do not, so long as they use an algorithm (such as
  MRHOF) which has certain properties.

- if we had multiple RPL instances in an LLN, using different metrics,
  then we would have multiple RPL Instances and DODAGs.  The different
  set of metrics would not co-exist in the same RPL Instance.


-- 
Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software Works 
IETF ROLL WG co-chair.    http://datatracker.ietf.org/wg/roll/charter/