[Gen-art] Genart last call review of draft-ietf-httpbis-targeted-cache-control-02

[Elwyn Davies via Datatracker <[e-mail]>]

Reviewer: Elwyn Davies
Review result: Ready with Nits

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Document: draft-ietf-httpbis-targeted-cache-control-02
Reviewer: Elwyn Davies
Review Date: 2021-12-23
IETF LC End Date: 2021-12-23
IESG Telechat date: Not scheduled for a telechat

Summary:  Ready except for a couple of nits and one possibe issue with an
informational reference that is not freely accessible to readers of the future
RFC.  I also wondered if a little more emphasis on the potential interactions
between multiple types of cache would be desirable.

Major issues:

Minor issues:

s2.3, para 4:  The infomational reference [AGE-PENALTY] is not a publically
available document.  This is not a vital reference and I expect that people
trying to build a CDN cache system would be aware of this discussion but it
would be useful to have a reference that is publically available to explain the
issue.

Nits/editorial comments:

s2.1, para 1: A reference to the IANA page for the is desirable
(https://www.iana.org/assignments/http-cache-directives/http-cache-directives.xhtml)

s2.2, para 1:  s/A cache that implement/A cache that implements/

s2.3, para 1:  In the last sentence:
In particular, a targeted cache might have longer freshness lifetimes available
to it than other caches, causing it to serve responses that appear to be
prematurely (or even immediately) stale to them,

It needs to be adjusted to make it clear what the final 'them' refer to..