Subject: [DNSOP] Barry Leiba's No Objection on draft-ietf-dnsop-server-cookies-04: (with COMMENT)

From: Barry Leiba via Datatracker <[email-masked]>
Date: Tue, 15 Dec 2020 21:46:39 -0800

Barry Leiba has entered the following ballot position for
draft-ietf-dnsop-server-cookies-04: No Objection

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COMMENT:
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Thanks for this; very useful.  I have two small points:

— Section 3 —

   It is reasonable to change the
   Client Cookie then only if it has been compromised or after a
   relatively long period of time such as no longer than a year.  Client
   Cookies are not expected to survive a program restart.

Itis anvery small thing, but “a relatively long period of time such as no
longer than a year” strikes me as an odd way to put it, and especially so
because of the sentence that follows it.  If you’re actually suggesting that a
year is a reasonable and likely choice, please say that more clearly. 
Otherwise, you might consider suggesting a shorter period as a (lower-case)
recommendation, with the year as a maximim... or, alternatively, leave it at
the vague “relatively long” with something like, “or after a relatively long
implementation-defined period of time.  The time period should be no longer
than a year, and in any case Client Cookies are not expected to survive a
program restart.”

— Section 4.2 —
Why is it a SHOULD, rather than a MUST, to zero the reserved field?  Why might
a server not zero it for good reason?  And wouldn’t it harm future
interoperability if implementations don’t, and an extension comes along that
uses bits in that field?