[Roll] Unassigned bits of the ... are reserved

Rahul Arvind Jadhav <rahul.jadhav@huawei.com> Tue, 30 April 2019 10:01 UTC

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From: Rahul Arvind Jadhav <rahul.jadhav@huawei.com>
To: roll <roll@ietf.org>
Thread-Topic: Unassigned bits of the ... are reserved
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Date: Tue, 30 Apr 2019 10:00:43 +0000
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Subject: [Roll] Unassigned bits of the ... are reserved
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Hello ROLL,

RPL (RFC6550) base objects and options have a couple of sentences in the context saying,
"Unassigned bits of the [MSG] are reserved. They MUST be set to zero on transmission and MUST be ignored on reception."

This text is present for all base objects including, DIO/DAO/DAO-ACK/CC.
Also it is present for following options, RIO/PIO/Transit Information Option/Solicited Information
But it is not present for following options, DODAG Configuration/DAG Metric Container/Pad1/PadN/RPL Target.

Want to understand which bits are referenced by this statement and why for certain options it is not mentioned?

<This point was commented upon by Alvaro during review of draft-ietf-roll-efficient-npdao-09>

Regards,
Rahul