Last Call Review of draft-freed-smtp-limits-06
review-freed-smtp-limits-06-opsdir-lc-dunbar-2023-09-26-00

I have reviewed this document as part of the Ops area directorate's ongoing
effort to review all IETF documents being processed by the IESG.  These
comments were written primarily for the benefit of the Ops area directors.
Document editors and WG chairs should treat these comments just like any other
last-call comments.

Summary:
This document defines a "Limits" extension for the Simple Mail Transfer
Protocol (SMTP).

The document specifies several limits to be registered with IANA. However, I
don't see the Limit value being specified. Does it mean that the document
simply proposes a new KEYWORD (LIMITS)?

I am not an expert at SMTP, I have some questions:
- The security consideration says that "a malicious server can use limits to
overly constrain clients". Q1: how to prevent clients access malicious server?
Q2: how does setting the KEYWORD LIMIT can help this problem

- Introduction section 6th paragraph says "makes it possible for clients to
avoid server errors and the problems they cause. Q: How can setting the LIMITE
helps Client avoid Server Errors?

Thank you,
Linda Dunbar