Subject: [OPSAWG] Ben Campbell's No Objection on draft-ietf-opsawg-mud-20: (with COMMENT)

From: Ben Campbell <[email-masked]>
Date: Sun, 15 Apr 2018 22:36:20 -0700

Ben Campbell has entered the following ballot position for
draft-ietf-opsawg-mud-20: No Objection

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COMMENT:
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Substantive:

§1.6, 2nd paragraph: Why is the SHOULD not a MUST?

§1.8, 4th paragraph: "The web server is typically run by or on behalf of the
manufacturer.
   Its domain name is that of the authority found in the MUD URL. "

These URLS are likely to be hardcoded, correct? This seems to point to
operational considerations, especially around Thing lifecycle and ownership.

Editorial/Nits:

Abstract: I'm not sure the use of the term "Things" will be obvious to a reader
of the abstract in isolation from the rest of the document. (Abstracts should
be able to stand alone.)

§1.1 : first paragraph: The idea that a Thing might have highly restricted
communication patterns seems core to the document. It would be helpful to
mention that earlier in §1.

§1.3, definition of "Manufacturer": The definition says that "Manufacturer" may
not necessarily be the entity that constructed the Thing. But that's the plain
English meaning of the word "manufacturer". If you don't want it to mean that,
please consider choosing a different term. ( for example, "authority")

§1.4: "... we assume that a device has so few
   capabilities that it will implement the least necessary capabilities
   to function properly."

That's a bit circular. Perhaps one of the two instances of "capabilities"
should have been "requirements"?

§1.8 4th paragraph: The 2nd (and last) sentence is a comma splice, and
otherwise difficult to parse.

§1.9, list item 7:  are we talking about transient disconnect or permanent
removal?

§2: "A MUD file consists of a YANG model ..."
A model instance, right? That is, not the model itself?

§3.8, 2nd sentence: Consider reformulating this as a construction of MUST.

§4: The idea of a "default" in bullet 2 seems in tension with the idea of
"Anything not explicitly permitted is forbidden" in bullet 1.

§14: Please define the concept of "east-west infection".