Re: [Anima] [saag] towards using of MUST-/SHOULD+/SHOULD- in draft-ietf-autonomic-control-plane-24

Brian E Carpenter <> Sat, 27 June 2020 04:05 UTC

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To: Nico Williams <>, Michael Richardson <>
Cc: Toerless Eckert <>, Russ Housley <>, Ben Kaduk <>,,
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From: Brian E Carpenter <>
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Date: Sat, 27 Jun 2020 16:05:41 +1200
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Subject: Re: [Anima] [saag] towards using of MUST-/SHOULD+/SHOULD- in draft-ietf-autonomic-control-plane-24
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On 27-Jun-20 15:06, Nico Williams wrote:
> On Fri, Jun 26, 2020 at 09:15:19PM -0400, Michael Richardson wrote:
>> 1) So, BCPs can point to multiple documents.
>>    BCP14 actually is RFC2119 and RFC8174 now, so we can add a third document if
>>    desired. That is, it's cheaper to not spin 2119.
> Sure.  Plus, RFC2119 is iconic, and used far and wide outside the IETF.
>> 2) I'm not claiming others won't use it, I just don't know if they will.
>>    Crypto progresses... what other things do that in the same way?
> Any time we have a migration from one [sub]protocol to a newer one and
> need to retain support for the old one for a while, we will need
> something like SHOULD-.  I agree this comes up most often in the context
> of cryptographic algorithms.

Interesting discussion but I want to see the ACP in the RFC Editor queue, can we just do what is required for that and nothing else?

I am about a millimetre away from proposing to recall the GRASP spec from the RFC Editor so that we can amputate its normative dependency on the ACP. I really wish I'd done that a year ago.

    Grumpy Brian