>  If a message has both Nonce and Timestamp options, the Nonce option
>  SHOULD precede the Timestamp option in the message.

Why? What value does this have (and its only a SHOULD, so receivers
can't count on it...). This seems useless.

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James Kempf: The value is that the host can process the nonce first
and discard the message quickly by matching against the nonce on the
message sent, before proceeding to the more time consuming time
check. Granted, the amount of time is probably not much in this case
(as is the case for a signature), and we can remove the SHOULD if the
gain in keeping it seems not proportional to the constraint.

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Thomas Narten: Seems to me that the order an implementation chooses to
process options does not need to be sequential. If it makes sense to
process the nonce first, then just don't do the verification prior to
looking for a nonce. Is this a significant implementation issue?

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Jari Arkko: I agree that this text is unnecessary in the draft.

(Note that upon reception, it is important to check
the nonce first (if applicable). This is because
otherwise clocks that are out of sync might lead to
messages being discarded even if nonces show that
they are fresh. But I think Section 5.3.4 requires
this correctly, Section 5.3.3 text is unnecessary.)

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Arkko: Timestamp and Nounce option order. Agreed not specifying order
is not needed. Related real technical issue, has to be taken care of
in correct order, check nounce first. Clocks not in sync, nounce will
work but timestamp will fail. But text for that is in.

Kempf: Agree

Action Item: Remove order requirement on option processing.

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