[core] Adam Roach's No Objection on draft-ietf-core-hop-limit-06: (with COMMENT)

[Adam Roach via Datatracker <[e-mail]>]

Adam Roach has entered the following ballot position for
draft-ietf-core-hop-limit-06: No Objection

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COMMENT:
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Thanks to everyone who worked on this document.

I'm a little surprised that the treatment of loops that go between HTTP and
CoAP networks involves a simple observation that detection of such cases simply
won't work, without any attempt at mitigation.

I'm sympathetic to the observation during WGLC that directly interworking with
RFC 8586 isn't feasible, but surprised that more primitive approaches to at
least preserving the CoAP Hop-Count as it crossed the HTTP network weren't
considered. There are aesthetic discussions to be had around, e.g., defining an
HTTP "Hop-Count" header field (which isn't acted on by the HTTP network, but
serves the purpose of preserving the value during transit) or overloading the
semantics (but not really the meaning) of the HTTP "Max-Forwards" header field,
or (in extremis) squirreling the Hop-Count away in the `pseudonym` portion of
the inserted HTTP Via header field.  But I think the high order bit here is
that preserving the Hop-Count value through the HTTP network would be trivial,
and would prevent the identified shortcoming of the current mechanism.