Re: [Roll] WGLC for draft-thubert-6man-flow-label-for-rpl-03

Michael Richardson <mcr+ietf@sandelman.ca> Thu, 14 August 2014 14:17 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Carsten Bormann <cabo@tzi.org>
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Date: Thu, 14 Aug 2014 10:16:52 -0400
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Cc: Routing Over Low power and Lossy networks <roll@ietf.org>, 6man WG <ipv6@ietf.org>, Ole Troan <otroan@employees.org>
Subject: Re: [Roll] WGLC for draft-thubert-6man-flow-label-for-rpl-03
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Carsten Bormann <cabo@tzi.org> wrote:
    > Again, the straw man at
    > http://tools.ietf.org/html/draft-bormann-6lo-rpl-mesh-00 saves the same
    > number of bytes.  Actually, for common cases, it enables one additional
    > optimization (saving one more byte) that is not available with the flow
    > label hack.  (On the other hand, due to the way RFC 6282 works, the
    > flow label hack saves one byte where both it and ECN are in use and the
    > common case does not apply.)

I read it, but I didn't understand it.
Is this something that fits into the 6lowpan adaptation header?

    > The disadvantage of the RPL mesh header is that this approach is not
    > available outside 6lo networks (i.e., networks employing adaptation
    > layers that use RFC 6282).  I’m not aware yet of a use case where that
    > is a problem.

    > In either encoding (RPL mesh header or flow label), it is probably a
    > good idea anyway to unpack the compressed information back into the RPL
    > IPv6 option when leaving the 6lo networks.

A good point, I think.

--
Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software Works
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