[core] Chair's review of draft-ietf-core-hop-limit-02.txt

Carsten Bormann <cabo@tzi.org> Thu, 21 February 2019 23:20 UTC

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From: Carsten Bormann <cabo@tzi.org>
Date: Fri, 22 Feb 2019 00:20:32 +0100
Cc: draft-ietf-core-hop-limit@ietf.org
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Subject: [core] Chair's review of draft-ietf-core-hop-limit-02.txt
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In preparation for the impending working-group last call, I have
reviewed draft-ietf-core-hop-limit-02.txt.  Substantive comments are
below; a set of small editorial comments is going to the authors in
parallel.

# Major

1. Is adding a hop-limit option now a recommendation that applies to
   all CoAP proxies?

2. I don't understand the rule about using cached copies.  As a
   general observation, rules like this should not simply be stated
   without a rationale why they are the way they are.

# Minor

1. The text could include a sentence about what happens when a proxy
   does not understand the option (nothing bad, but loops consisting
   entirely of such proxies will not be terminated).

2. The way the diagnostic payloads are formed seems to rely on a space
   separator, but does not exclude its use inside the separated items.

# Editorial

1. The terminology could be aligned some more (e.g., avoid "agent",
   use "request" or "response" instead of "message" where
   possible). Details in the editorial comments.

Grüße, Carsten