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Document: draft-ietf-httpbis-cache-16
Reviewer: Mohit Sethi
Review Date: 2021-05-30
IETF LC End Date: 2021-06-10
IESG Telechat date: 2021-06-17

Summary: This draft specification defines HTTP caches and header fields for controlling the cache behavior.

Major issues:

Minor issues: 
- In the HTML version of the draft, the reference to [Semantics] does not work properly. I looked at the xml source which looks fine. I suspect it is something to do with the tooling.

- It is not clear to me which draft is creating the "Hypertext Transfer Protocol (HTTP) Field Name Registry". It seems both this draft and draft-ietf-httpbis-semantics are creating it? Perhaps you could remove the text in this draft saying "introduce the new" and just ask IANA to update the registry with fields in Table 1 of this draft.

Nits/editorial comments: 

- Section 1: When does a client or server act as "tunnel"? I don't know if it is absolutely necessary to explain the term. You can decide.

- Section 1: HTTP caching's goal is significantly improving performance -> HTTP caching's goal is to significantly improve performance?

- Section 1.3: Maybe it is obvious to many readers, but I was not sure what is meant by a "canned string"?

- Section 3 vs Section 4: "A cache MUST NOT store a response to a request unless:" does not have a comma before unless while "When presented with a request, a cache MUST NOT reuse a stored response, unless:" has a comma before unless?

- Some of the bullets in section 3 and 4 were hard to parse. Take for example: "When presented with a request, a cache MUST NOT reuse a stored response, unless: the stored response does not contain the no-cache cache directive (Section 5.2.2.4), unless it is successfully validated (Section 4.3), and". I am not sure how to simplify the text on all these requirements.