Subject: Murray Kucherawy's Discuss on draft-ietf-6man-mtu-option-13: (with DISCUSS and COMMENT)

From: Murray Kucherawy via Datatracker <[email-masked]>
Date: Wed, 06 Apr 2022 22:54:34 -0700

Murray Kucherawy has entered the following ballot position for
draft-ietf-6man-mtu-option-13: Discuss

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DISCUSS:
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Alvaro and Zahed pointed out concerns about the SHOULDs in Sections 6.1 and
6.2, and since all three of us tripped on the same text, I'd like to discuss
them.  My own angle is that they're SHOULDs but it's not clear to me why they
aren't MUSTs.   SHOULD offers the implementer a choice; if we're sure these
need to be SHOULDs, then what advice might we provide to implementers that
think they have legitimate reasons not to do what they say?

For instance, if I'm coding a router that understands HBH but is configured not
to honor this option, why might I not ignore the option and forward the packet?

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COMMENT:
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In Sections 1 and 2, you refer to "this draft", e.g.:

  The purpose of this draft is to improve the situation ...

When published, this won't be a draft.  I suggest changing both to "document".