[Acme] Robert Wilton's No Objection on draft-ietf-acme-subdomains-06: (with COMMENT)

[Robert Wilton via Datatracker <[e-mail]>]

Robert Wilton has entered the following ballot position for
draft-ietf-acme-subdomains-06: No Objection

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COMMENT:
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Hi,

Thanks for this document.

One minor nit on the definition of subdomain and ancestor domain:

Subdomain has been clarified in this document to remove the ambiguity of
whether a given domain is a subdomain of itself.

However, looking at the definition of ancestor domain:

   *  Ancestor Domain: a domain is an ancestor domain of a subdomain if
      it contains that subdomain, as per the [RFC8499] definition of
      subdomain.  For example, for the host name "nnn.mmm.example.com",
      both "mmm.example.com" and "example.com" are ancestor domains of
      "nnn.mmm.example.com".  Note that the comparisons here are done on
      whole labels; that is, "oo.example.com" is not an ancestor domain
      of "ooo.example.com"

It specifically references the RFC8499 definition of subdomain rather than the
one clarified in the document, raising the question whether a domain is also an
ancestor of itself, and whether that ambiguity is intentional for some reason. 
Hence, I would propose that the definition of ancestor domain is tied back to
the definition of subdomain in this document rather than RFC8499.

Regards,
Rob