[Roll] Martin Vigoureux's No Objection on draft-ietf-roll-efficient-npdao-12: (with COMMENT)

[Martin Vigoureux via Datatracker <[e-mail]>]

Martin Vigoureux has entered the following ballot position for
draft-ietf-roll-efficient-npdao-12: No Objection

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COMMENT:
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Hi,

thank you for this document.

I only have minor comments/questions:
* Please expand LLNs

* it's a bit pity that D flag is bit '0' in DCO and bit '1' in DCO-ACK

* 0x05 RPL Target and 0x06 Transit Information are RPL Control Message Options
but they are not really DCO Options as they MUST be present.

* it is not fully clear to me whether Path Sequence can or should be
incremented on DCO retry.

* I'm not sure this has any meaning (didn't have enough time to think about
this scenario) but what would happen if D sends a DAO which never reaches A and
A decides to send an unsolicited DCO. How would D react to receiving a message
with a sequence number which is smaller than the one it has sent? Is that an
issue?

* I feel that imposing the unused flags to be set to zero is not necessary.
MUST ignore the unspecified flags is sufficient.